Crystal Structure of PKG I:cGMP Complex Reveals a cGMP-Mediated Dimeric Interface that Facilitates cGMP-Induced Activation

KAUST Repository

Kim, Jeong Joo

2016-04-09

Cyclic guanosine monophosphate (cGMP)-dependent protein kinase (PKG) is a key regulator of smooth muscle and vascular tone and represents an important drug target for treating hypertensive diseases and erectile dysfunction. Despite its importance, its activation mechanism is not fully understood. To understand the activation mechanism, we determined a 2.5 Å crystal structure of the PKG I regulatory (R) domain bound with cGMP, which represents the activated state. Although we used a monomeric domain for crystallization, the structure reveals that two R domains form a symmetric dimer where the cGMP bound at high-affinity pockets provide critical dimeric contacts. Small-angle X-ray scattering and mutagenesis support this dimer model, suggesting that the dimer interface modulates kinase activation. Finally, structural comparison with the homologous cyclic AMP-dependent protein kinase reveals that PKG is drastically different from protein kinase A in its active conformation, suggesting a novel activation mechanism for PKG. Kim et al. obtain the first crystal structure of the PKG I R domain bound with cGMP representing its activated state. It reveals a symmetric R dimer where cGMP molecules provide dimeric contacts. This R-R interaction prevents the high-affinity inhibitory interaction between R-C domain and sustains activation. © 2016 Elsevier Ltd.

Crystal Structure of PKG I:cGMP Complex Reveals a cGMP-Mediated Dimeric Interface that Facilitates cGMP-Induced Activation

KAUST Repository

Kim, Jeong  Joo; Lorenz, Robin; Arold, Stefan T.; Reger, Albert  S.; Sankaran, Banumathi; Casteel, Darren  E.; Herberg, Friedrich  W.; Kim, Choel

2016-01-01

Cyclic guanosine monophosphate (cGMP)-dependent protein kinase (PKG) is a key regulator of smooth muscle and vascular tone and represents an important drug target for treating hypertensive diseases and erectile dysfunction. Despite its importance, its activation mechanism is not fully understood. To understand the activation mechanism, we determined a 2.5 Å crystal structure of the PKG I regulatory (R) domain bound with cGMP, which represents the activated state. Although we used a monomeric domain for crystallization, the structure reveals that two R domains form a symmetric dimer where the cGMP bound at high-affinity pockets provide critical dimeric contacts. Small-angle X-ray scattering and mutagenesis support this dimer model, suggesting that the dimer interface modulates kinase activation. Finally, structural comparison with the homologous cyclic AMP-dependent protein kinase reveals that PKG is drastically different from protein kinase A in its active conformation, suggesting a novel activation mechanism for PKG. Kim et al. obtain the first crystal structure of the PKG I R domain bound with cGMP representing its activated state. It reveals a symmetric R dimer where cGMP molecules provide dimeric contacts. This R-R interaction prevents the high-affinity inhibitory interaction between R-C domain and sustains activation. © 2016 Elsevier Ltd.

Community Lenses Revealing the Role of Sociocultural Environment on Physical Activity

Science.gov (United States)

Belon, Ana Paula; Nieuwendyk, Laura M.; Vallianatos, Helen; Nykiforuk, Candace I. J.

2016-01-01

Purpose To identify perceptions of how sociocultural environment enabled and hindered physical activity (PA) participation. Design Community-based participatory research. Setting Two semirural and two urban communities located in Alberta, Canada. Participants Thirty-five people (74.3% females, 71.4% aged 25–64 years) across the four communities. Method PhotoVoice activities occurred over 3 months during the spring of 2009. Participants were asked to document perceived environmental attributes that might foster or inhibit PA in their community. Photographs and narratives were shared in one-on-one interviews. Line-by-line coding of the transcripts was independently conducted by two researchers using an inductive approach. Codes were arranged into themes and subthemes, which were then organized into the Analysis Grid for Environments Linked to Obesity (ANGELO) framework. Results Six main themes (accompanied by subthemes) emerged: sociocultural aesthetics, safety, social involvement, PA motivation, cultural ideas of recreation, and car culture. Representative quotes and photographs illustrate enablers and obstacles identified by participants. Conclusion This PhotoVoice study revealed how aspects of participants’ sociocultural environments shaped their decisions to be physically active. Providing more PA resources is only one step in the promotion of supportive environments. Strategies should also account for the beautification and maintenance of communities, increasing feelings of safety, enhancement of social support among community members, popularization of PA, and mitigating car culture, among others. PMID:25973966

Community Lenses Revealing the Role of Sociocultural Environment on Physical Activity.

Science.gov (United States)

Belon, Ana Paula; Nieuwendyk, Laura M; Vallianatos, Helen; Nykiforuk, Candace I J

2016-01-01

To identify perceptions of how sociocultural environment enabled and hindered physical activity (PA) participation. Community-based participatory research. Two semirural and two urban communities located in Alberta, Canada. Thirty-five people (74.3% females, 71.4% aged 25-64 years) across the four communities. PhotoVoice activities occurred over 3 months during the spring of 2009. Participants were asked to document perceived environmental attributes that might foster or inhibit PA in their community. Photographs and narratives were shared in one-on-one interviews. Line-by-line coding of the transcripts was independently conducted by two researchers using an inductive approach. Codes were arranged into themes and subthemes, which were then organized into the Analysis Grid for Environments Linked to Obesity (ANGELO) framework. Six main themes (accompanied by subthemes) emerged: sociocultural aesthetics, safety, social involvement, PA motivation, cultural ideas of recreation, and car culture. Representative quotes and photographs illustrate enablers and obstacles identified by participants. This PhotoVoice study revealed how aspects of participants' sociocultural environments shaped their decisions to be physically active. Providing more PA resources is only one step in the promotion of supportive environments. Strategies should also account for the beautification and maintenance of communities, increasing feelings of safety, enhancement of social support among community members, popularization of PA, and mitigating car culture, among others.

Inter-species activity correlations reveal functional correspondences between monkey and human brain areas

Science.gov (United States)

Mantini, Dante; Hasson, Uri; Betti, Viviana; Perrucci, Mauro G.; Romani, Gian Luca; Corbetta, Maurizio; Orban, Guy A.; Vanduffel, Wim

2012-01-01

Evolution-driven functional changes in the primate brain are typically assessed by aligning monkey and human activation maps using cortical surface expansion models. These models use putative homologous areas as registration landmarks, assuming they are functionally correspondent. In cases where functional changes have occurred in an area, this assumption prohibits to reveal whether other areas may have assumed lost functions. Here we describe a method to examine functional correspondences across species. Without making spatial assumptions, we assess similarities in sensory-driven functional magnetic resonance imaging responses between monkey (Macaca mulatta) and human brain areas by means of temporal correlation. Using natural vision data, we reveal regions for which functional processing has shifted to topologically divergent locations during evolution. We conclude that substantial evolution-driven functional reorganizations have occurred, not always consistent with cortical expansion processes. This novel framework for evaluating changes in functional architecture is crucial to building more accurate evolutionary models. PMID:22306809

Dual gene activation and knockout screen reveals directional dependencies in genetic networks. | Office of Cancer Genomics

Science.gov (United States)

Understanding the direction of information flow is essential for characterizing how genetic networks affect phenotypes. However, methods to find genetic interactions largely fail to reveal directional dependencies. We combine two orthogonal Cas9 proteins from Streptococcus pyogenes and Staphylococcus aureus to carry out a dual screen in which one gene is activated while a second gene is deleted in the same cell. We analyze the quantitative effects of activation and knockout to calculate genetic interaction and directionality scores for each gene pair.

Adaptability and selectivity of human peroxisome proliferator-activated receptor (PPAR) pan agonists revealed from crystal structures

International Nuclear Information System (INIS)

Oyama, Takuji; Toyota, Kenji; Waku, Tsuyoshi; Hirakawa, Yuko; Nagasawa, Naoko; Kasuga, Jun-ichi; Hashimoto, Yuichi; Miyachi, Hiroyuki; Morikawa, Kosuke

2009-01-01

The structures of the ligand-binding domains (LBDs) of human peroxisome proliferator-activated receptors (PPARα, PPARγ and PPARδ) in complexes with a pan agonist, an α/δ dual agonist and a PPARδ-specific agonist were determined. The results explain how each ligand is recognized by the PPAR LBDs at an atomic level. Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear hormone receptor family, which is defined as transcriptional factors that are activated by the binding of ligands to their ligand-binding domains (LBDs). Although the three PPAR subtypes display different tissue distribution patterns and distinct pharmacological profiles, they all are essentially related to fatty-acid and glucose metabolism. Since the PPARs share similar three-dimensional structures within the LBDs, synthetic ligands which simultaneously activate two or all of the PPARs could be potent candidates in terms of drugs for the treatment of abnormal metabolic homeostasis. The structures of several PPAR LBDs were determined in complex with synthetic ligands, derivatives of 3-(4-alkoxyphenyl)propanoic acid, which exhibit unique agonistic activities. The PPARα and PPARγ LBDs were complexed with the same pan agonist, TIPP-703, which activates all three PPARs and their crystal structures were determined. The two LBD–ligand complex structures revealed how the pan agonist is adapted to the similar, but significantly different, ligand-binding pockets of the PPARs. The structures of the PPARδ LBD in complex with an α/δ-selective ligand, TIPP-401, and with a related δ-specific ligand, TIPP-204, were also determined. The comparison between the two PPARδ complexes revealed how each ligand exhibits either a ‘dual selective’ or ‘single specific’ binding mode

A chimeric prokaryotic pentameric ligand–gated channel reveals distinct pathways of activation

Science.gov (United States)

Schmandt, Nicolaus; Velisetty, Phanindra; Chalamalasetti, Sreevatsa V.; Stein, Richard A.; Bonner, Ross; Talley, Lauren; Parker, Mark D.; Mchaourab, Hassane S.; Yee, Vivien C.; Lodowski, David T.

2015-01-01

Recent high resolution structures of several pentameric ligand–gated ion channels have provided unprecedented details of their molecular architecture. However, the conformational dynamics and structural rearrangements that underlie gating and allosteric modulation remain poorly understood. We used a combination of electrophysiology, double electron–electron resonance (DEER) spectroscopy, and x-ray crystallography to investigate activation mechanisms in a novel functional chimera with the extracellular domain (ECD) of amine-gated Erwinia chrysanthemi ligand–gated ion channel, which is activated by primary amines, and the transmembrane domain of Gloeobacter violaceus ligand–gated ion channel, which is activated by protons. We found that the chimera was independently gated by primary amines and by protons. The crystal structure of the chimera in its resting state, at pH 7.0 and in the absence of primary amines, revealed a closed-pore conformation and an ECD that is twisted with respect to the transmembrane region. Amine- and pH-induced conformational changes measured by DEER spectroscopy showed that the chimera exhibits a dual mode of gating that preserves the distinct conformational changes of the parent channels. Collectively, our findings shed light on both conserved and divergent features of gating mechanisms in this class of channels, and will facilitate the design of better allosteric modulators. PMID:26415570

SNOW AVALANCHE ACTIVITY IN PARÂNG SKI AREA REVEALED BY TREE-RINGS

Directory of Open Access Journals (Sweden)

F. MESEȘAN

2014-11-01

Full Text Available Snow Avalanche Activity in Parâng Ski Area Revealed by Tree-Rings. Snow avalanches hold favorable conditions to manifest in Parâng Mountains but only one event is historically known, without destructive impact upon infrastructure or fatalities and this region wasn’t yet the object of avalanche research. The existing ski infrastructure of Parâng resort located in the west of Parâng Mountains is proposed to be extended in the steep slopes of subalpine area. Field evidence pinpoints that these steep slopes were affected by snow avalanches in the past. In this study we analyzed 11 stem discs and 31 increment cores extracted from 22 spruces (Picea abies (L. Karst impacted by avalanches, in order to obtain more information about past avalanches activity. Using the dendrogeomorphological approach we found 13 avalanche events that occurred along Scărița avalanche path, since 1935 until 2012, nine of them produced in the last 20 years. The tree-rings data inferred an intense snow avalanche activity along this avalanche path. This study not only calls for more research in the study area but also proves that snow avalanches could constitute an important restrictive factor for the tourism infrastructure and related activities in the area. It must be taken into consideration by the future extension of tourism infrastructure. Keywords: snow avalanche, Parâng Mountains, dendrogeomorphology, ski area.

Distribution patterns of firearm discharge residues as revealed by neutron activation analysis

International Nuclear Information System (INIS)

Pillay, K.K.S.; Driscoll, D.C.; Jester, W.A.

1975-01-01

A systematic investigation using a variety of handguns has revealed the existence of distinguisable distribution patterns of firearm discharge residues on surfaces below the flight path of a bullet. The residues are identificable even at distances of 12 meters from the gun using nondestructive neutron activation analysis. The results of these investigations show that the distribution pattern for a gun is reproducible using similar ammunition and that there exist two distinct regions to the patterns developed between the firearm and the target-one with respect to the position of the gun and the other in the vicinity of the target. The judicious applications of these findings could be of significant value in criminal investigations. (T.G.)

SAFARI: Searching Asteroids For Activity Revealing Indicators

Science.gov (United States)

Curtis, Anthony; Chandler, Colin Orion; Mommert, Michael; Sheppard, Scott; Trujillo, Chadwick A.

2018-06-01

We present results on one of the deepest and widest systematic searches for active asteroids, objects in the main-belt which behave dynamically like asteroids but display comet-like comae. This activity comes from a variety of sources, such as the sublimation of ices or rotational breakup, the former of which offers an opportunity to study a family of protoplanetary ices different than those seen in comets and Kuiper Belt objects. Indications of activity may be detected through visual or spectroscopic evidence of gas or dust emissions. However, these objects are still poorly understood, with only about 25 identified to date. We looked for activity indicators with a pipeline that examined ~35,000 deep images taken with the Dark Energy Camera (DECam) mounted on the 4-meter Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile. Our pipeline was configured to perform astrometry on DECam images and produce thumbnail images of known asteroids in the field to be examined by eye for signs of activity. We detected three previously identified active asteroids, one of which has shown repeated signs of activity in these data. Our proof of concept demonstrates 1) our novel informatics approach can locate active asteroids 2) DECam data are well suited to search for active asteroids. We will discuss the design structure of our pipeline, adjustments that had to be made for the specific dataset to improve performance, and the the significance of detecting activity in the main-belt. The authors acknowledge funding for this project through NSF grant number AST-1461200.

Structure of protease-cleaved Escherichia coli α-2-macroglobulin reveals a putative mechanism of conformational activation for protease entrapment

International Nuclear Information System (INIS)

Fyfe, Cameron D.; Grinter, Rhys; Josts, Inokentijs; Mosbahi, Khedidja; Roszak, Aleksander W.; Cogdell, Richard J.; Wall, Daniel M.; Burchmore, Richard J. S.; Byron, Olwyn; Walker, Daniel

2015-01-01

The X-ray structure of protease-cleaved E. coli α-2-macroglobulin is described, which reveals a putative mechanism of activation and conformational change essential for protease inhibition. Bacterial α-2-macroglobulins have been suggested to function in defence as broad-spectrum inhibitors of host proteases that breach the outer membrane. Here, the X-ray structure of protease-cleaved Escherichia coli α-2-macroglobulin is described, which reveals a putative mechanism of activation and conformational change essential for protease inhibition. In this competitive mechanism, protease cleavage of the bait-region domain results in the untethering of an intrinsically disordered region of this domain which disrupts native interdomain interactions that maintain E. coli α-2-macroglobulin in the inactivated form. The resulting global conformational change results in entrapment of the protease and activation of the thioester bond that covalently links to the attacking protease. Owing to the similarity in structure and domain architecture of Escherichia coli α-2-macroglobulin and human α-2-macroglobulin, this protease-activation mechanism is likely to operate across the diverse members of this group

Structure of protease-cleaved Escherichia coli α-2-macroglobulin reveals a putative mechanism of conformational activation for protease entrapment

Energy Technology Data Exchange (ETDEWEB)

Fyfe, Cameron D.; Grinter, Rhys; Josts, Inokentijs; Mosbahi, Khedidja [University of Glasgow, Glasgow G12 8QQ, Scotland (United Kingdom); Roszak, Aleksander W. [University of Glasgow, Glasgow G12 8QQ, Scotland (United Kingdom); University of Glasgow, Glasgow G12 8QQ, Scotland (United Kingdom); Cogdell, Richard J.; Wall, Daniel M.; Burchmore, Richard J. S.; Byron, Olwyn; Walker, Daniel, E-mail: daniel.walker@glasgow.ac.uk [University of Glasgow, Glasgow G12 8QQ, Scotland (United Kingdom)

2015-06-30

The X-ray structure of protease-cleaved E. coli α-2-macroglobulin is described, which reveals a putative mechanism of activation and conformational change essential for protease inhibition. Bacterial α-2-macroglobulins have been suggested to function in defence as broad-spectrum inhibitors of host proteases that breach the outer membrane. Here, the X-ray structure of protease-cleaved Escherichia coli α-2-macroglobulin is described, which reveals a putative mechanism of activation and conformational change essential for protease inhibition. In this competitive mechanism, protease cleavage of the bait-region domain results in the untethering of an intrinsically disordered region of this domain which disrupts native interdomain interactions that maintain E. coli α-2-macroglobulin in the inactivated form. The resulting global conformational change results in entrapment of the protease and activation of the thioester bond that covalently links to the attacking protease. Owing to the similarity in structure and domain architecture of Escherichia coli α-2-macroglobulin and human α-2-macroglobulin, this protease-activation mechanism is likely to operate across the diverse members of this group.

Active sensing associated with spatial learning reveals memory-based attention in an electric fish.

Science.gov (United States)

Jun, James J; Longtin, André; Maler, Leonard

2016-05-01

Active sensing behaviors reveal what an animal is attending to and how it changes with learning. Gymnotus sp, a gymnotiform weakly electric fish, generates an electric organ discharge (EOD) as discrete pulses to actively sense its surroundings. We monitored freely behaving gymnotid fish in a large dark "maze" and extracted their trajectories and EOD pulse pattern and rate while they learned to find food with electrically detectable landmarks as cues. After training, they more rapidly found food using shorter, more stereotyped trajectories and spent more time near the food location. We observed three forms of active sensing: sustained high EOD rates per unit distance (sampling density), transient large increases in EOD rate (E-scans) and stereotyped scanning movements (B-scans) were initially strong at landmarks and food, but, after learning, intensified only at the food location. During probe (no food) trials, after learning, the fish's search area and intense active sampling was still centered on the missing food location, but now also increased near landmarks. We hypothesize that active sensing is a behavioral manifestation of attention and essential for spatial learning; the fish use spatial memory of landmarks and path integration to reach the expected food location and confine their attention to this region. Copyright © 2016 the American Physiological Society.

Functional metabolomics reveals novel active products in the DHA metabolome

Directory of Open Access Journals (Sweden)

Masakazu eShinohara

2012-04-01

Full Text Available Endogenous mechanisms for successful resolution of an acute inflammatory response and the local return to homeostasis are of interest because excessive inflammation underlies many human diseases. In this review, we provide an update and overview of functional metabolomics that identified a new bioactive metabolome of docosahexaenoic acid (DHA. Systematic studies revealed that DHA was converted to DHEA-derived novel bioactive products as well as aspirin-triggered (AT forms of protectins. The new oxygenated DHEA derived products blocked PMN chemotaxis, reduced P-selectin expression and platelet-leukocyte adhesion, and showed organ protection in ischemia/reperfusion injury. These products activated cannabinoid receptor (CB2 receptor and not CB1 receptors. The AT-PD1 reduced neutrophil (PMN recruitment in murine peritonitis. With human cells, AT-PD1 decreased transendothelial PMN migration as well as enhanced efferocytosis of apoptotic human PMN by macrophages. The recent findings reviewed here indicate that DHEA oxidative metabolism and aspirin-triggered conversion of DHA produce potent novel molecules with anti-inflammatory and organ-protective properties, opening the DHA metabolome functional roles.

Activation of acid-sensing ion channels by localized proton transient reveals their role in proton signaling.

Science.gov (United States)

Zeng, Wei-Zheng; Liu, Di-Shi; Liu, Lu; She, Liang; Wu, Long-Jun; Xu, Tian-Le

2015-09-15

Extracellular transients of pH alterations likely mediate signal transduction in the nervous system. Neuronal acid-sensing ion channels (ASICs) act as sensors for extracellular protons, but the mechanism underlying ASIC activation remains largely unknown. Here, we show that, following activation of a light-activated proton pump, Archaerhodopsin-3 (Arch), proton transients induced ASIC currents in both neurons and HEK293T cells co-expressing ASIC1a channels. Using chimera proteins that bridge Arch and ASIC1a by a glycine/serine linker, we found that successful coupling occurred within 15 nm distance. Furthermore, two-cell sniffer patch recording revealed that regulated release of protons through either Arch or voltage-gated proton channel Hv1 activated neighbouring cells expressing ASIC1a channels. Finally, computational modelling predicted the peak proton concentration at the intercellular interface to be at pH 6.7, which is acidic enough to activate ASICs in vivo. Our results highlight the pathophysiological role of proton signalling in the nervous system.

Spatiotemporal dynamics of word retrieval in speech production revealed by cortical high-frequency band activity.

Science.gov (United States)

Riès, Stephanie K; Dhillon, Rummit K; Clarke, Alex; King-Stephens, David; Laxer, Kenneth D; Weber, Peter B; Kuperman, Rachel A; Auguste, Kurtis I; Brunner, Peter; Schalk, Gerwin; Lin, Jack J; Parvizi, Josef; Crone, Nathan E; Dronkers, Nina F; Knight, Robert T

2017-06-06

Word retrieval is core to language production and relies on complementary processes: the rapid activation of lexical and conceptual representations and word selection, which chooses the correct word among semantically related competitors. Lexical and conceptual activation is measured by semantic priming. In contrast, word selection is indexed by semantic interference and is hampered in semantically homogeneous (HOM) contexts. We examined the spatiotemporal dynamics of these complementary processes in a picture naming task with blocks of semantically heterogeneous (HET) or HOM stimuli. We used electrocorticography data obtained from frontal and temporal cortices, permitting detailed spatiotemporal analysis of word retrieval processes. A semantic interference effect was observed with naming latencies longer in HOM versus HET blocks. Cortical response strength as indexed by high-frequency band (HFB) activity (70-150 Hz) amplitude revealed effects linked to lexical-semantic activation and word selection observed in widespread regions of the cortical mantle. Depending on the subsecond timing and cortical region, HFB indexed semantic interference (i.e., more activity in HOM than HET blocks) or semantic priming effects (i.e., more activity in HET than HOM blocks). These effects overlapped in time and space in the left posterior inferior temporal gyrus and the left prefrontal cortex. The data do not support a modular view of word retrieval in speech production but rather support substantial overlap of lexical-semantic activation and word selection mechanisms in the brain.

Structure-Activity Relationship and Molecular Mechanics Reveal the Importance of Ring Entropy in the Biosynthesis and Activity of a Natural Product.

Science.gov (United States)

Tran, Hai L; Lexa, Katrina W; Julien, Olivier; Young, Travis S; Walsh, Christopher T; Jacobson, Matthew P; Wells, James A

2017-02-22

Macrocycles are appealing drug candidates due to their high affinity, specificity, and favorable pharmacological properties. In this study, we explored the effects of chemical modifications to a natural product macrocycle upon its activity, 3D geometry, and conformational entropy. We chose thiocillin as a model system, a thiopeptide in the ribosomally encoded family of natural products that exhibits potent antimicrobial effects against Gram-positive bacteria. Since thiocillin is derived from a genetically encoded peptide scaffold, site-directed mutagenesis allows for rapid generation of analogues. To understand thiocillin's structure-activity relationship, we generated a site-saturation mutagenesis library covering each position along thiocillin's macrocyclic ring. We report the identification of eight unique compounds more potent than wild-type thiocillin, the best having an 8-fold improvement in potency. Computational modeling of thiocillin's macrocyclic structure revealed a striking requirement for a low-entropy macrocycle for activity. The populated ensembles of the active mutants showed a rigid structure with few adoptable conformations while inactive mutants showed a more flexible macrocycle which is unfavorable for binding. This finding highlights the importance of macrocyclization in combination with rigidifying post-translational modifications to achieve high-potency binding.

Common brain regions underlying different arithmetic operations as revealed by conjunct fMRI-BOLD activation.

Science.gov (United States)

Fehr, Thorsten; Code, Chris; Herrmann, Manfred

2007-10-03

The issue of how and where arithmetic operations are represented in the brain has been addressed in numerous studies. Lesion studies suggest that a network of different brain areas are involved in mental calculation. Neuroimaging studies have reported inferior parietal and lateral frontal activations during mental arithmetic using tasks of different complexities and using different operators (addition, subtraction, etc.). Indeed, it has been difficult to compare brain activation across studies because of the variety of different operators and different presentation modalities used. The present experiment examined fMRI-BOLD activity in participants during calculation tasks entailing different arithmetic operations -- addition, subtraction, multiplication and division -- of different complexities. Functional imaging data revealed a common activation pattern comprising right precuneus, left and right middle and superior frontal regions during all arithmetic operations. All other regional activations were operation specific and distributed in prominently frontal, parietal and central regions when contrasting complex and simple calculation tasks. The present results largely confirm former studies suggesting that activation patterns due to mental arithmetic appear to reflect a basic anatomical substrate of working memory, numerical knowledge and processing based on finger counting, and derived from a network originally related to finger movement. We emphasize that in mental arithmetic research different arithmetic operations should always be examined and discussed independently of each other in order to avoid invalid generalizations on arithmetics and involved brain areas.

Mutational and structural analyses of Caldanaerobius polysaccharolyticus Man5B reveal novel active site residues for family 5 glycoside hydrolases.

Directory of Open Access Journals (Sweden)

Takuji Oyama

Full Text Available CpMan5B is a glycoside hydrolase (GH family 5 enzyme exhibiting both β-1,4-mannosidic and β-1,4-glucosidic cleavage activities. To provide insight into the amino acid residues that contribute to catalysis and substrate specificity, we solved the structure of CpMan5B at 1.6 Å resolution. The structure revealed several active site residues (Y12, N92 and R196 in CpMan5B that are not present in the active sites of other structurally resolved GH5 enzymes. Residue R196 in GH5 enzymes is thought to be strictly conserved as a histidine that participates in an electron relay network with the catalytic glutamates, but we show that an arginine fulfills a functionally equivalent role and is found at this position in every enzyme in subfamily GH5_36, which includes CpMan5B. Residue N92 is required for full enzymatic activity and forms a novel bridge over the active site that is absent in other family 5 structures. Our data also reveal a role of Y12 in establishing the substrate preference for CpMan5B. Using these molecular determinants as a probe allowed us to identify Man5D from Caldicellulosiruptor bescii as a mannanase with minor endo-glucanase activity.

Mutational and structural analyses of Caldanaerobius polysaccharolyticus Man5B reveal novel active site residues for family 5 glycoside hydrolases.

Science.gov (United States)

Oyama, Takuji; Schmitz, George E; Dodd, Dylan; Han, Yejun; Burnett, Alanna; Nagasawa, Naoko; Mackie, Roderick I; Nakamura, Haruki; Morikawa, Kosuke; Cann, Isaac

2013-01-01

CpMan5B is a glycoside hydrolase (GH) family 5 enzyme exhibiting both β-1,4-mannosidic and β-1,4-glucosidic cleavage activities. To provide insight into the amino acid residues that contribute to catalysis and substrate specificity, we solved the structure of CpMan5B at 1.6 Å resolution. The structure revealed several active site residues (Y12, N92 and R196) in CpMan5B that are not present in the active sites of other structurally resolved GH5 enzymes. Residue R196 in GH5 enzymes is thought to be strictly conserved as a histidine that participates in an electron relay network with the catalytic glutamates, but we show that an arginine fulfills a functionally equivalent role and is found at this position in every enzyme in subfamily GH5_36, which includes CpMan5B. Residue N92 is required for full enzymatic activity and forms a novel bridge over the active site that is absent in other family 5 structures. Our data also reveal a role of Y12 in establishing the substrate preference for CpMan5B. Using these molecular determinants as a probe allowed us to identify Man5D from Caldicellulosiruptor bescii as a mannanase with minor endo-glucanase activity.

Platelet proteome reveals novel pathways of platelet activation and platelet-mediated immunoregulation in dengue.

Directory of Open Access Journals (Sweden)

Monique Ramos de Oliveira Trugilho

2017-05-01

Full Text Available Dengue is the most prevalent human arbovirus disease worldwide. Dengue virus (DENV infection causes syndromes varying from self-limiting febrile illness to severe dengue. Although dengue pathophysiology is not completely understood, it is widely accepted that increased inflammation plays important roles in dengue pathogenesis. Platelets are blood cells classically known as effectors of hemostasis which have been increasingly recognized to have major immune and inflammatory activities. Nevertheless, the phenotype and effector functions of platelets in dengue pathogenesis are not completely understood. Here we used quantitative proteomics to investigate the protein content of platelets in clinical samples from patients with dengue compared to platelets from healthy donors. Our assays revealed a set of 252 differentially abundant proteins. In silico analyses associated these proteins with key molecular events including platelet activation and inflammatory responses, and with events not previously attributed to platelets during dengue infection including antigen processing and presentation, proteasome activity, and expression of histones. From these results, we conducted functional assays using samples from a larger cohort of patients and demonstrated evidence for platelet activation indicated by P-selectin (CD62P translocation and secretion of granule-stored chemokines by platelets. In addition, we found evidence that DENV infection triggers HLA class I synthesis and surface expression by a mechanism depending on functional proteasome activity. Furthermore, we demonstrate that cell-free histone H2A released during dengue infection binds to platelets, increasing platelet activation. These findings are consistent with functional importance of HLA class I, proteasome subunits, and histones that we found exclusively in proteome analysis of platelets in samples from dengue patients. Our study provides the first in-depth characterization of the platelet

Glycoprotein profiles of macrophages at different stages of activation as revealed by lectin binding after electrophoretic separation.

Science.gov (United States)

Irimura, T; North, S M; Nicolson, G L

1987-01-01

Glycoprotein profiles of rat macrophages (M phi) at different stages of activation were studied by examining the reactivity of various lectins to the glycoproteins separated by polyacrylamide gel electrophoresis. Ricinus communis agglutinin 1 (RCA1) revealed several components including glycoproteins of Mr 160 kDa and 65 kDa prominent in resident M phi. A pokeweed mitogen (PWM) isolectin, Pa-4, recognizes branched poly(N-acetyllactosamine)-type carbohydrate chains, and revealed a significant increase in glycoproteins of Mr ranging from 70 kDa to 150 kDa on thioglycolate-elicited M phi. Increased reactivity of PWM to thioglycolate-elicited M phi was observed by direct binding of 125I-labeled Pa-4 to intact or glutaraldehyde-fixed M phi. Histochemical staining of formaldehyde-fixed M phi in vitro with biotinylated Pa-4 was consistent with the gel analysis, that is, resident M phi had no reactivity while thioglycolate-elicited M phi showed slight reactivity. Alveolar and intratumoral M phi bound more Pa-4 than resident or thioglycolate-elicited M phi. The PWM isolectin may therefore serve as a marker for an early stage of M phi activation.

Purification of reversibly oxidized proteins (PROP reveals a redox switch controlling p38 MAP kinase activity.

Directory of Open Access Journals (Sweden)

Dennis J Templeton

2010-11-01

Full Text Available Oxidation of cysteine residues of proteins is emerging as an important means of regulation of signal transduction, particularly of protein kinase function. Tools to detect and quantify cysteine oxidation of proteins have been a limiting factor in understanding the role of cysteine oxidation in signal transduction. As an example, the p38 MAP kinase is activated by several stress-related stimuli that are often accompanied by in vitro generation of hydrogen peroxide. We noted that hydrogen peroxide inhibited p38 activity despite paradoxically increasing the activating phosphorylation of p38. To address the possibility that cysteine oxidation may provide a negative regulatory effect on p38 activity, we developed a biochemical assay to detect reversible cysteine oxidation in intact cells. This procedure, PROP, demonstrated in vivo oxidation of p38 in response to hydrogen peroxide and also to the natural inflammatory lipid prostaglandin J2. Mutagenesis of the potential target cysteines showed that oxidation occurred preferentially on residues near the surface of the p38 molecule. Cysteine oxidation thus controls a functional redox switch regulating the intensity or duration of p38 activity that would not be revealed by immunodetection of phosphoprotein commonly interpreted as reflective of p38 activity.

13C ENDOR Spectroscopy of Lipoxygenase-Substrate Complexes Reveals the Structural Basis for C-H Activation by Tunneling.

Science.gov (United States)

Horitani, Masaki; Offenbacher, Adam R; Carr, Cody A Marcus; Yu, Tao; Hoeke, Veronika; Cutsail, George E; Hammes-Schiffer, Sharon; Klinman, Judith P; Hoffman, Brian M

2017-02-08

In enzymatic C-H activation by hydrogen tunneling, reduced barrier width is important for efficient hydrogen wave function overlap during catalysis. For native enzymes displaying nonadiabatic tunneling, the dominant reactive hydrogen donor-acceptor distance (DAD) is typically ca. 2.7 Å, considerably shorter than normal van der Waals distances. Without a ground state substrate-bound structure for the prototypical nonadiabatic tunneling system, soybean lipoxygenase (SLO), it has remained unclear whether the requisite close tunneling distance occurs through an unusual ground state active site arrangement or by thermally sampling conformational substates. Herein, we introduce Mn 2+ as a spin-probe surrogate for the SLO Fe ion; X-ray diffraction shows Mn-SLO is structurally faithful to the native enzyme. 13 C ENDOR then reveals the locations of 13 C10 and reactive 13 C11 of linoleic acid relative to the metal; 1 H ENDOR and molecular dynamics simulations of the fully solvated SLO model using ENDOR-derived restraints give additional metrical information. The resulting three-dimensional representation of the SLO active site ground state contains a reactive (a) conformer with hydrogen DAD of ∼3.1 Å, approximately van der Waals contact, plus an inactive (b) conformer with even longer DAD, establishing that stochastic conformational sampling is required to achieve reactive tunneling geometries. Tunneling-impaired SLO variants show increased DADs and variations in substrate positioning and rigidity, confirming previous kinetic and theoretical predictions of such behavior. Overall, this investigation highlights the (i) predictive power of nonadiabatic quantum treatments of proton-coupled electron transfer in SLO and (ii) sensitivity of ENDOR probes to test, detect, and corroborate kinetically predicted trends in active site reactivity and to reveal unexpected features of active site architecture.

Live imaging of cysteine-cathepsin activity reveals dynamics of focal inflammation, angiogenesis, and polyp growth.

Directory of Open Access Journals (Sweden)

Elias Gounaris

2008-08-01

Full Text Available It has been estimated that up to 30% of detectable polyps in patients regress spontaneously. One major challenge in the evaluation of effective therapy of cancer is the readout for tumor regression and favorable biological response to therapy. Inducible near infra-red (NIR fluorescent probes were utilized to visualize intestinal polyps of mice hemizygous for a novel truncation of the Adenomatous Polyposis coli (APC gene. Laser Scanning Confocal Microscopy in live mice allowed visualization of cathepsin activity in richly vascularized benign dysplastic lesions. Using biotinylated suicide inhibitors we quantified increased activities of the Cathepsin B & Z in the polyps. More than (3/4 of the probe signal was localized in CD11b(+Gr1(+ myeloid derived suppressor cells (MDSC and CD11b(+F4/80(+ macrophages infiltrating the lesions. Polyposis was attenuated through genetic ablation of cathepsin B, and suppressed by neutralization of TNFalpha in mice. In both cases, diminished probe signal was accounted for by loss of MDSC. Thus, in vivo NIR imaging of focal cathepsin activity reveals inflammatory reactions etiologically linked with cancer progression and is a suitable approach for monitoring response to therapy.

Core microbial functional activities in ocean environments revealed by global metagenomic profiling analyses.

KAUST Repository

Ferreira, Ari J S

2014-06-12

Metagenomics-based functional profiling analysis is an effective means of gaining deeper insight into the composition of marine microbial populations and developing a better understanding of the interplay between the functional genome content of microbial communities and abiotic factors. Here we present a comprehensive analysis of 24 datasets covering surface and depth-related environments at 11 sites around the world\\'s oceans. The complete datasets comprises approximately 12 million sequences, totaling 5,358 Mb. Based on profiling patterns of Clusters of Orthologous Groups (COGs) of proteins, a core set of reference photic and aphotic depth-related COGs, and a collection of COGs that are associated with extreme oxygen limitation were defined. Their inferred functions were utilized as indicators to characterize the distribution of light- and oxygen-related biological activities in marine environments. The results reveal that, while light level in the water column is a major determinant of phenotypic adaptation in marine microorganisms, oxygen concentration in the aphotic zone has a significant impact only in extremely hypoxic waters. Phylogenetic profiling of the reference photic/aphotic gene sets revealed a greater variety of source organisms in the aphotic zone, although the majority of individual photic and aphotic depth-related COGs are assigned to the same taxa across the different sites. This increase in phylogenetic and functional diversity of the core aphotic related COGs most probably reflects selection for the utilization of a broad range of alternate energy sources in the absence of light.

Core microbial functional activities in ocean environments revealed by global metagenomic profiling analyses.

KAUST Repository

Ferreira, Ari J S; Siam, Rania; Setubal, Joã o C; Moustafa, Ahmed; Sayed, Ahmed; Chambergo, Felipe S; Dawe, Adam S; Ghazy, Mohamed A; Sharaf, Hazem; Ouf, Amged; Alam, Intikhab; Abdel-Haleem, Alyaa M; Lehvä slaiho, Heikki; Ramadan, Eman; Antunes, André ; Stingl, Ulrich; Archer, John A.C.; Jankovic, Boris R; Sogin, Mitchell; Bajic, Vladimir B.; El-Dorry, Hamza

2014-01-01

Metagenomics-based functional profiling analysis is an effective means of gaining deeper insight into the composition of marine microbial populations and developing a better understanding of the interplay between the functional genome content of microbial communities and abiotic factors. Here we present a comprehensive analysis of 24 datasets covering surface and depth-related environments at 11 sites around the world's oceans. The complete datasets comprises approximately 12 million sequences, totaling 5,358 Mb. Based on profiling patterns of Clusters of Orthologous Groups (COGs) of proteins, a core set of reference photic and aphotic depth-related COGs, and a collection of COGs that are associated with extreme oxygen limitation were defined. Their inferred functions were utilized as indicators to characterize the distribution of light- and oxygen-related biological activities in marine environments. The results reveal that, while light level in the water column is a major determinant of phenotypic adaptation in marine microorganisms, oxygen concentration in the aphotic zone has a significant impact only in extremely hypoxic waters. Phylogenetic profiling of the reference photic/aphotic gene sets revealed a greater variety of source organisms in the aphotic zone, although the majority of individual photic and aphotic depth-related COGs are assigned to the same taxa across the different sites. This increase in phylogenetic and functional diversity of the core aphotic related COGs most probably reflects selection for the utilization of a broad range of alternate energy sources in the absence of light.

Core microbial functional activities in ocean environments revealed by global metagenomic profiling analyses.

Directory of Open Access Journals (Sweden)

Ari J S Ferreira

Full Text Available Metagenomics-based functional profiling analysis is an effective means of gaining deeper insight into the composition of marine microbial populations and developing a better understanding of the interplay between the functional genome content of microbial communities and abiotic factors. Here we present a comprehensive analysis of 24 datasets covering surface and depth-related environments at 11 sites around the world's oceans. The complete datasets comprises approximately 12 million sequences, totaling 5,358 Mb. Based on profiling patterns of Clusters of Orthologous Groups (COGs of proteins, a core set of reference photic and aphotic depth-related COGs, and a collection of COGs that are associated with extreme oxygen limitation were defined. Their inferred functions were utilized as indicators to characterize the distribution of light- and oxygen-related biological activities in marine environments. The results reveal that, while light level in the water column is a major determinant of phenotypic adaptation in marine microorganisms, oxygen concentration in the aphotic zone has a significant impact only in extremely hypoxic waters. Phylogenetic profiling of the reference photic/aphotic gene sets revealed a greater variety of source organisms in the aphotic zone, although the majority of individual photic and aphotic depth-related COGs are assigned to the same taxa across the different sites. This increase in phylogenetic and functional diversity of the core aphotic related COGs most probably reflects selection for the utilization of a broad range of alternate energy sources in the absence of light.

Water diffusion closely reveals neural activity status in rat brain loci affected by anesthesia.

Directory of Open Access Journals (Sweden)

Yoshifumi Abe

2017-04-01

Full Text Available Diffusion functional MRI (DfMRI reveals neuronal activation even when neurovascular coupling is abolished, contrary to blood oxygenation level-dependent (BOLD functional MRI (fMRI. Here, we show that the water apparent diffusion coefficient (ADC derived from DfMRI increased in specific rat brain regions under anesthetic conditions, reflecting the decreased neuronal activity observed with local field potentials (LFPs, especially in regions involved in wakefulness. In contrast, BOLD signals showed nonspecific changes, reflecting systemic effects of the anesthesia on overall brain hemodynamics status. Electrical stimulation of the central medial thalamus nucleus (CM exhibiting this anesthesia-induced ADC increase led the animals to transiently wake up. Infusion in the CM of furosemide, a specific neuronal swelling blocker, led the ADC to increase further locally, although LFP activity remained unchanged, and increased the current threshold awakening the animals under CM electrical stimulation. Oppositely, induction of cell swelling in the CM through infusion of a hypotonic solution (-80 milliosmole [mOsm] artificial cerebrospinal fluid [aCSF] led to a local ADC decrease and a lower current threshold to wake up the animals. Strikingly, the local ADC changes produced by blocking or enhancing cell swelling in the CM were also mirrored remotely in areas functionally connected to the CM, such as the cingulate and somatosensory cortex. Together, those results strongly suggest that neuronal swelling is a significant mechanism underlying DfMRI.

Distinct summer and winter bacterial communities in the active layer of Svalbard permafrost revealed by DNA- and RNA-based analyses

Science.gov (United States)

Schostag, Morten; Stibal, Marek; Jacobsen, Carsten S.; Bælum, Jacob; Taş, Neslihan; Elberling, Bo; Jansson, Janet K.; Semenchuk, Philipp; Priemé, Anders

2015-01-01

The active layer of soil overlaying permafrost in the Arctic is subjected to dramatic annual changes in temperature and soil chemistry, which likely affect bacterial activity and community structure. We studied seasonal variations in the bacterial community of active layer soil from Svalbard (78°N) by co-extracting DNA and RNA from 12 soil cores collected monthly over a year. PCR amplicons of 16S rRNA genes (DNA) and reverse transcribed transcripts (cDNA) were quantified and sequenced to test for the effect of low winter temperature and seasonal variation in concentration of easily degradable organic matter on the bacterial communities. The copy number of 16S rRNA genes and transcripts revealed no distinct seasonal changes indicating potential bacterial activity during winter despite soil temperatures well below −10°C. Multivariate statistical analysis of the bacterial diversity data (DNA and cDNA libraries) revealed a season-based clustering of the samples, and, e.g., the relative abundance of potentially active Cyanobacteria peaked in June and Alphaproteobacteria increased over the summer and then declined from October to November. The structure of the bulk (DNA-based) community was significantly correlated with pH and dissolved organic carbon, while the potentially active (RNA-based) community structure was not significantly correlated with any of the measured soil parameters. A large fraction of the 16S rRNA transcripts was assigned to nitrogen-fixing bacteria (up to 24% in June) and phototrophic organisms (up to 48% in June) illustrating the potential importance of nitrogen fixation in otherwise nitrogen poor Arctic ecosystems and of phototrophic bacterial activity on the soil surface. PMID:25983731

National Security Strategy: A Flawed Guide to the Future, Political Science

National Research Council Canada - National Science Library

Leahy, Michael

2003-01-01

.... The effects of 9/11 and the emphasis on global terrorism are unmistakable. The talking heads in the media who focused, their critiques on the overt statement of a policy of preemption missed the forest for the trees...

Deletion of a regulatory gene within the cpk gene cluster reveals novel antibacterial activity in Streptomyces coelicolor A3(2)

NARCIS (Netherlands)

Gottelt, Marco; Kol, Stefan; Gomez-Escribano, Juan Pablo; Bibb, Mervyn; Takano, Eriko

Genome sequencing of Streptomyces coelicolor A3(2) revealed an uncharacterized type I polyketide synthase gene cluster (cpk) Here we describe the discovery of a novel antibacterial activity (abCPK) and a yellow-pigmented secondary metabolite (yCPK) after deleting a presumed pathway-specific

Altered spontaneous brain activity in adolescent boys with pure conduct disorder revealed by regional homogeneity analysis.

Science.gov (United States)

Wu, Qiong; Zhang, Xiaocui; Dong, Daifeng; Wang, Xiang; Yao, Shuqiao

2017-07-01

Functional magnetic resonance imaging (fMRI) studies have revealed abnormal neural activity in several brain regions of adolescents with conduct disorder (CD) performing various tasks. However, little is known about the spontaneous neural activity in people with CD in a resting state. The aims of this study were to investigate CD-associated regional activity abnormalities and to explore the relationship between behavioral impulsivity and regional activity abnormalities. Resting-state fMRI (rs-fMRI) scans were administered to 28 adolescents with CD and 28 age-, gender-, and IQ-matched healthy controls (HCs). The rs-fMRI data were subjected to regional homogeneity (ReHo) analysis. ReHo can demonstrate the temporal synchrony of regional blood oxygen level-dependent signals and reflect the coordination of local neuronal activity facilitating similar goals or representations. Compared to HCs, the CD group showed increased ReHo bilaterally in the insula as well as decreased ReHo in the right inferior parietal lobule, right middle temporal gyrus and right fusiform gyrus, left anterior cerebellum anterior, and right posterior cerebellum. In the CD group, mean ReHo values in the left and the right insula correlated positively with Barratt Impulsivity Scale (BIS) total scores. The results suggest that CD is associated with abnormal intrinsic brain activity, mainly in the cerebellum and temporal-parietal-limbic cortices, regions that are related to emotional and cognitive processing. BIS scores in adolescents with CD may reflect severity of abnormal neuronal synchronization in the insula.

Thermodynamic coupling between activation and inactivation gating in potassium channels revealed by free energy molecular dynamics simulations.

Science.gov (United States)

Pan, Albert C; Cuello, Luis G; Perozo, Eduardo; Roux, Benoît

2011-12-01

The amount of ionic current flowing through K(+) channels is determined by the interplay between two separate time-dependent processes: activation and inactivation gating. Activation is concerned with the stimulus-dependent opening of the main intracellular gate, whereas inactivation is a spontaneous conformational transition of the selectivity filter toward a nonconductive state occurring on a variety of timescales. A recent analysis of multiple x-ray structures of open and partially open KcsA channels revealed the mechanism by which movements of the inner activation gate, formed by the inner helices from the four subunits of the pore domain, bias the conformational changes at the selectivity filter toward a nonconductive inactivated state. This analysis highlighted the important role of Phe103, a residue located along the inner helix, near the hinge position associated with the opening of the intracellular gate. In the present study, we use free energy perturbation molecular dynamics simulations (FEP/MD) to quantitatively elucidate the thermodynamic basis for the coupling between the intracellular gate and the selectivity filter. The results of the FEP/MD calculations are in good agreement with experiments, and further analysis of the repulsive, van der Waals dispersive, and electrostatic free energy contributions reveals that the energetic basis underlying the absence of inactivation in the F103A mutation in KcsA is the absence of the unfavorable steric interaction occurring with the large Ile100 side chain in a neighboring subunit when the intracellular gate is open and the selectivity filter is in a conductive conformation. Macroscopic current analysis shows that the I100A mutant indeed relieves inactivation in KcsA, but to a lesser extent than the F103A mutant.

Ultrastructural and Molecular Analyses Reveal Enhanced Nucleolar Activity in Medicago truncatula Cells Overexpressing the MtTdp2α Gene

Science.gov (United States)

Macovei, Anca; Faè, Matteo; Biggiogera, Marco; de Sousa Araújo, Susana; Carbonera, Daniela; Balestrazzi, Alma

2018-01-01

The role of tyrosyl-DNA phosphodiesterase 2 (Tdp2) involved in the repair of 5′-end-blocking DNA lesions is still poorly explored in plants. To gain novel insights, Medicago truncatula suspension cultures overexpressing the MtTdp2α gene (Tdp2α-13C and Tdp2α-28 lines, respectively) and a control (CTRL) line carrying the empty vector were investigated. Transmission electron microscopy (TEM) revealed enlarged nucleoli (up to 44% expansion of the area, compared to CTRL), the presence of nucleolar vacuoles, increased frequency of multinucleolate cells (up to 4.3-fold compared to CTRL) and reduced number of ring-shaped nucleoli in Tdp2α-13C and Tdp2α-28 lines. Ultrastructural data suggesting for enhanced nucleolar activity in MtTdp2α-overexpressing lines were integrated with results from bromouridine incorporation. The latter revealed an increase of labeled transcripts in both Tdp2α-13C and Tdp2α-28 cells, within the nucleolus and in the extra-nucleolar region. MtTdp2α-overexpressing cells showed tolerance to etoposide, a selective inhibitor of DNA topoisomerase II, as evidenced by DNA diffusion assay. TEM analysis revealed etoposide-induced rearrangements within the nucleolus, resembling the nucleolar caps observed in animal cells under transcription impairment. Based on these findings it is evident that MtTdp2α-overexpression enhances nucleolar activity in plant cells. PMID:29868059

Ultrastructural and Molecular Analyses Reveal Enhanced Nucleolar Activity in Medicago truncatula Cells Overexpressing the MtTdp2α Gene

Directory of Open Access Journals (Sweden)

Anca Macovei

2018-05-01

Full Text Available The role of tyrosyl-DNA phosphodiesterase 2 (Tdp2 involved in the repair of 5′-end-blocking DNA lesions is still poorly explored in plants. To gain novel insights, Medicago truncatula suspension cultures overexpressing the MtTdp2α gene (Tdp2α-13C and Tdp2α-28 lines, respectively and a control (CTRL line carrying the empty vector were investigated. Transmission electron microscopy (TEM revealed enlarged nucleoli (up to 44% expansion of the area, compared to CTRL, the presence of nucleolar vacuoles, increased frequency of multinucleolate cells (up to 4.3-fold compared to CTRL and reduced number of ring-shaped nucleoli in Tdp2α-13C and Tdp2α-28 lines. Ultrastructural data suggesting for enhanced nucleolar activity in MtTdp2α-overexpressing lines were integrated with results from bromouridine incorporation. The latter revealed an increase of labeled transcripts in both Tdp2α-13C and Tdp2α-28 cells, within the nucleolus and in the extra-nucleolar region. MtTdp2α-overexpressing cells showed tolerance to etoposide, a selective inhibitor of DNA topoisomerase II, as evidenced by DNA diffusion assay. TEM analysis revealed etoposide-induced rearrangements within the nucleolus, resembling the nucleolar caps observed in animal cells under transcription impairment. Based on these findings it is evident that MtTdp2α-overexpression enhances nucleolar activity in plant cells.

The Kazanga festival : ethnicity as cultural mediation and transformation in central western Zambia

NARCIS (Netherlands)

Binsbergen, van W.M.J.

1994-01-01

This paper explores the cultural dynamics of ethnicity in the context of a postcolonial African State, Zambia. The opening sections define ethnicity and pinpoint its central dilemma: while unmistakably constructed and thus selectively empowering the brokers coordinating the construction process,

Ribosome•RelA structures reveal the mechanism of stringent response activation

Science.gov (United States)

Loveland, Anna B; Bah, Eugene; Madireddy, Rohini; Zhang, Ying; Brilot, Axel F; Grigorieff, Nikolaus; Korostelev, Andrei A

2016-01-01

Stringent response is a conserved bacterial stress response underlying virulence and antibiotic resistance. RelA/SpoT-homolog proteins synthesize transcriptional modulators (p)ppGpp, allowing bacteria to adapt to stress. RelA is activated during amino-acid starvation, when cognate deacyl-tRNA binds to the ribosomal A (aminoacyl-tRNA) site. We report four cryo-EM structures of E. coli RelA bound to the 70S ribosome, in the absence and presence of deacyl-tRNA accommodating in the 30S A site. The boomerang-shaped RelA with a wingspan of more than 100 Å wraps around the A/R (30S A-site/RelA-bound) tRNA. The CCA end of the A/R tRNA pins the central TGS domain against the 30S subunit, presenting the (p)ppGpp-synthetase domain near the 30S spur. The ribosome and A/R tRNA are captured in three conformations, revealing hitherto elusive states of tRNA engagement with the ribosomal decoding center. Decoding-center rearrangements are coupled with the step-wise 30S-subunit 'closure', providing insights into the dynamics of high-fidelity tRNA decoding. DOI: http://dx.doi.org/10.7554/eLife.17029.001 PMID:27434674

Activity in human visual and parietal cortex reveals object-based attention in working memory.

Science.gov (United States)

Peters, Benjamin; Kaiser, Jochen; Rahm, Benjamin; Bledowski, Christoph

2015-02-25

Visual attention enables observers to select behaviorally relevant information based on spatial locations, features, or objects. Attentional selection is not limited to physically present visual information, but can also operate on internal representations maintained in working memory (WM) in service of higher-order cognition. However, only little is known about whether attention to WM contents follows the same principles as attention to sensory stimuli. To address this question, we investigated in humans whether the typically observed effects of object-based attention in perception are also evident for object-based attentional selection of internal object representations in WM. In full accordance with effects in visual perception, the key behavioral and neuronal characteristics of object-based attention were observed in WM. Specifically, we found that reaction times were shorter when shifting attention to memory positions located on the currently attended object compared with equidistant positions on a different object. Furthermore, functional magnetic resonance imaging and multivariate pattern analysis of visuotopic activity in visual (areas V1-V4) and parietal cortex revealed that directing attention to one position of an object held in WM also enhanced brain activation for other positions on the same object, suggesting that attentional selection in WM activates the entire object. This study demonstrated that all characteristic features of object-based attention are present in WM and thus follows the same principles as in perception. Copyright © 2015 the authors 0270-6474/15/353360-10$15.00/0.

Glycan structure of Gc Protein-derived Macrophage Activating Factor as revealed by mass spectrometry.

Science.gov (United States)

Borges, Chad R; Rehder, Douglas S

2016-09-15

Disagreement exists regarding the O-glycan structure attached to human vitamin D binding protein (DBP). Previously reported evidence indicated that the O-glycan of the Gc1S allele product is the linear core 1 NeuNAc-Gal-GalNAc-Thr trisaccharide. Here, glycan structural evidence is provided from glycan linkage analysis and over 30 serial glycosidase-digestion experiments which were followed by analysis of the intact protein by electrospray ionization mass spectrometry (ESI-MS). Results demonstrate that the O-glycan from the Gc1F protein is the same linear trisaccharide found on the Gc1S protein and that the hexose residue is galactose. In addition, the putative anti-cancer derivative of DBP known as Gc Protein-derived Macrophage Activating Factor (GcMAF, which is formed by the combined action of β-galactosidase and neuraminidase upon DBP) was analyzed intact by ESI-MS, revealing that the activating E. coli β-galactosidase cleaves nothing from the protein-leaving the glycan structure of active GcMAF as a Gal-GalNAc-Thr disaccharide, regardless of the order in which β-galactosidase and neuraminidase are applied. Moreover, glycosidase digestion results show that α-N-Acetylgalactosamindase (nagalase) lacks endoglycosidic function and only cleaves the DBP O-glycan once it has been trimmed down to a GalNAc-Thr monosaccharide-precluding the possibility of this enzyme removing the O-glycan trisaccharide from cancer-patient DBP in vivo. Copyright © 2016 Elsevier Inc. All rights reserved.

The structure of Plasmodium falciparum serine hydroxymethyltransferase reveals a novel redox switch that regulates its activities

Energy Technology Data Exchange (ETDEWEB)

Chitnumsub, Penchit; Ittarat, Wanwipa; Jaruwat, Aritsara; Noytanom, Krittikar [National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Paholyothin Road, Klong 1, Klong Luang, Pathumthani 12120 (Thailand); Amornwatcharapong, Watcharee [Mahidol University, Bangkok (Thailand); Pornthanakasem, Wichai [National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Paholyothin Road, Klong 1, Klong Luang, Pathumthani 12120 (Thailand); Chaiyen, Pimchai [Mahidol University, Bangkok (Thailand); Yuthavong, Yongyuth; Leartsakulpanich, Ubolsree [National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Paholyothin Road, Klong 1, Klong Luang, Pathumthani 12120 (Thailand)

2014-06-01

The crystal structure of P. falciparum SHMT revealed snapshots of an intriguing disulfide/sulfhydryl switch controlling the functional activity. Plasmodium falciparum serine hydroxymethyltransferase (PfSHMT), an enzyme in the dTMP synthesis cycle, is an antimalarial target because inhibition of its expression or function has been shown to be lethal to the parasite. As the wild-type enzyme could not be crystallized, protein engineering of residues on the surface was carried out. The surface-engineered mutant PfSHMT-F292E was successfully crystallized and its structure was determined at 3 Å resolution. The PfSHMT-F292E structure is a good representation of PfSHMT as this variant revealed biochemical properties similar to those of the wild type. Although the overall structure of PfSHMT is similar to those of other SHMTs, unique features including the presence of two loops and a distinctive cysteine pair formed by Cys125 and Cys364 in the tetrahydrofolate (THF) substrate binding pocket were identified. These structural characteristics have never been reported in other SHMTs. Biochemical characterization and mutation analysis of these two residues confirm that they act as a disulfide/sulfhydryl switch to regulate the THF-dependent catalytic function of the enzyme. This redox switch is not present in the human enzyme, in which the cysteine pair is absent. The data reported here can be further exploited as a new strategy to specifically disrupt the activity of the parasite enzyme without interfering with the function of the human enzyme.

The structure of Plasmodium falciparum serine hydroxymethyltransferase reveals a novel redox switch that regulates its activities

International Nuclear Information System (INIS)

Chitnumsub, Penchit; Ittarat, Wanwipa; Jaruwat, Aritsara; Noytanom, Krittikar; Amornwatcharapong, Watcharee; Pornthanakasem, Wichai; Chaiyen, Pimchai; Yuthavong, Yongyuth; Leartsakulpanich, Ubolsree

2014-01-01

The crystal structure of P. falciparum SHMT revealed snapshots of an intriguing disulfide/sulfhydryl switch controlling the functional activity. Plasmodium falciparum serine hydroxymethyltransferase (PfSHMT), an enzyme in the dTMP synthesis cycle, is an antimalarial target because inhibition of its expression or function has been shown to be lethal to the parasite. As the wild-type enzyme could not be crystallized, protein engineering of residues on the surface was carried out. The surface-engineered mutant PfSHMT-F292E was successfully crystallized and its structure was determined at 3 Å resolution. The PfSHMT-F292E structure is a good representation of PfSHMT as this variant revealed biochemical properties similar to those of the wild type. Although the overall structure of PfSHMT is similar to those of other SHMTs, unique features including the presence of two loops and a distinctive cysteine pair formed by Cys125 and Cys364 in the tetrahydrofolate (THF) substrate binding pocket were identified. These structural characteristics have never been reported in other SHMTs. Biochemical characterization and mutation analysis of these two residues confirm that they act as a disulfide/sulfhydryl switch to regulate the THF-dependent catalytic function of the enzyme. This redox switch is not present in the human enzyme, in which the cysteine pair is absent. The data reported here can be further exploited as a new strategy to specifically disrupt the activity of the parasite enzyme without interfering with the function of the human enzyme

Lasting modulation effects of rTMS on neural activity and connectivity as revealed by resting-state EEG.

Science.gov (United States)

Ding, Lei; Shou, Guofa; Yuan, Han; Urbano, Diamond; Cha, Yoon-Hee

2014-07-01

The long-lasting neuromodulatory effects of repetitive transcranial magnetic stimulation (rTMS) are of great interest for therapeutic applications in various neurological and psychiatric disorders, due to which functional connectivity among brain regions is profoundly disturbed. Classic TMS studies selectively alter neural activity in specific brain regions and observe neural activity changes on nonperturbed areas to infer underlying connectivity and its changes. Less has been indicated in direct measures of functional connectivity and/or neural network and on how connectivity/network alterations occur. Here, we developed a novel analysis framework to directly investigate both neural activity and connectivity changes induced by rTMS from resting-state EEG (rsEEG) acquired in a group of subjects with a chronic disorder of imbalance, known as the mal de debarquement syndrome (MdDS). Resting-state activity in multiple functional brain areas was identified through a data-driven blind source separation analysis on rsEEG data, and the connectivity among them was characterized using a phase synchronization measure. Our study revealed that there were significant long-lasting changes in resting-state neural activity, in theta, low alpha, and high alpha bands and neural networks in theta, low alpha, high alpha and beta bands, over broad cortical areas 4 to 5 h after the last application of rTMS in a consecutive five-day protocol. Our results of rsEEG connectivity further indicated that the changes, mainly in the alpha band, over the parietal and occipital cortices from pre- to post-TMS sessions were significantly correlated, in both magnitude and direction, to symptom changes in this group of subjects with MdDS. This connectivity measure not only suggested that rTMS can generate positive treatment effects in MdDS patients, but also revealed new potential targets for future therapeutic trials to improve treatment effects. It is promising that the new connectivity measure

Abnormal regional spontaneous neuronal activity associated with symptom severity in treatment-naive patients with obsessive-compulsive disorder revealed by resting-state functional MRI.

Science.gov (United States)

Qiu, Linlin; Fu, Xiangshuai; Wang, Shuai; Tang, Qunfeng; Chen, Xingui; Cheng, Lin; Zhang, Fuquan; Zhou, Zhenhe; Tian, Lin

2017-02-15

A large number of neuroimaging studies have revealed the dysfunction of brain activities in obsessive-compulsive disorder (OCD) during various tasks. However, regional spontaneous activity abnormalities in OCD are gradually being revealed. In this current study, we aimed to investigate cerebral regions with abnormal spontaneous activity using resting-state functional magnetic resonance imaging (fMRI) and further explored the relationship between the spontaneous neuronal activity and symptom severity of patients with OCD. Thirty-one patients with OCD and 32 age-and sex-matched normal controls received the fMRI scans and fractional amplitude of low-frequency fluctuation (fALFF) approach was applied to identify the abnormal brain activity. We found that patients with OCD showed decreased fALFF not only in the cortical-striato-thalamo-cortical (CSTC) circuits like the thalamus, but also in other cerebral systems like the cerebellum, the parietal cortex and the temporal cortex. Additionally, OCD patients demonstrated significant associations between decreased fALFF and obsessive-compulsive symptom severity in the thalamus, the paracentral lobule and the cerebellum. Our results provide evidence for abnormal spontaneous neuronal activity in distributed cerebral areas and support the notion that brain areas outside the CSTC circuits may also play an important role in the pathophysiology of OCD. Copyright © 2017 Elsevier B.V. All rights reserved.

Near scale-free dynamics in neural population activity of waking/sleeping rats revealed by multiscale analysis.

Directory of Open Access Journals (Sweden)

Leonid A Safonov

Full Text Available A neuron embedded in an intact brain, unlike an isolated neuron, participates in network activity at various spatial resolutions. Such multiple scale spatial dynamics is potentially reflected in multiple time scales of temporal dynamics. We identify such multiple dynamical time scales of the inter-spike interval (ISI fluctuations of neurons of waking/sleeping rats by means of multiscale analysis. The time scale of large non-Gaussianity in the ISI fluctuations, measured with the Castaing method, ranges up to several minutes, markedly escaping the low-pass filtering characteristics of neurons. A comparison between neural activity during waking and sleeping reveals that non-Gaussianity is stronger during waking than sleeping throughout the entire range of scales observed. We find a remarkable property of near scale independence of the magnitude correlations as the primary cause of persistent non-Gaussianity. Such scale-invariance of correlations is characteristic of multiplicative cascade processes and raises the possibility of the existence of a scale independent memory preserving mechanism.

38 CFR 3.303 - Principles relating to service connection.

Science.gov (United States)

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Principles relating to... Evaluations; Service Connection § 3.303 Principles relating to service connection. (a) General. Service... are medical principles so universally recognized as to constitute fact (clear and unmistakable proof...

Structures of BmrR-Drug Complexes Reveal a Rigid Multidrug Binding Pocket And Transcription Activation Through Tyrosine Expulsion

Energy Technology Data Exchange (ETDEWEB)

Newberry, K.J.; Huffman, J.L.; Miller, M.C.; Vazquez-Laslop, N.; Neyfakh, A.A.; Brennan, R.G.

2009-05-22

BmrR is a member of the MerR family and a multidrug binding transcription factor that up-regulates the expression of the bmr multidrug efflux transporter gene in response to myriad lipophilic cationic compounds. The structural mechanism by which BmrR binds these chemically and structurally different drugs and subsequently activates transcription is poorly understood. Here, we describe the crystal structures of BmrR bound to rhodamine 6G (R6G) or berberine (Ber) and cognate DNA. These structures reveal each drug stacks against multiple aromatic residues with their positive charges most proximal to the carboxylate group of Glu-253 and that, unlike other multidrug binding pockets, that of BmrR is rigid. Substitution of Glu-253 with either alanine (E253A) or glutamine (E253Q) results in unpredictable binding affinities for R6G, Ber, and tetraphenylphosphonium. Moreover, these drug binding studies reveal that the negative charge of Glu-253 is not important for high affinity binding to Ber and tetraphenylphosphonium but plays a more significant, but unpredictable, role in R6G binding. In vitro transcription data show that E253A and E253Q are constitutively active, and structures of the drug-free E253A-DNA and E253Q-DNA complexes support a transcription activation mechanism requiring the expulsion of Tyr-152 from the multidrug binding pocket. In sum, these data delineate the mechanism by which BmrR binds lipophilic, monovalent cationic compounds and suggest the importance of the redundant negative electrostatic nature of this rigid drug binding pocket that can be used to discriminate against molecules that are not substrates of the Bmr multidrug efflux pump.

Lost for emotion words: What motor and limbic brain activity reveals about autism and semantic theory

Science.gov (United States)

Moseley, Rachel L.; Shtyrov, Yury; Mohr, Bettina; Lombardo, Michael V.; Baron-Cohen, Simon; Pulvermüller, Friedemann

2015-01-01

Autism spectrum conditions (ASC) are characterised by deficits in understanding and expressing emotions and are frequently accompanied by alexithymia, a difficulty in understanding and expressing emotion words. Words are differentially represented in the brain according to their semantic category and these difficulties in ASC predict reduced activation to emotion-related words in limbic structures crucial for affective processing. Semantic theories view ‘emotion actions’ as critical for learning the semantic relationship between a word and the emotion it describes, such that emotion words typically activate the cortical motor systems involved in expressing emotion actions such as facial expressions. As ASC are also characterised by motor deficits and atypical brain structure and function in these regions, motor structures would also be expected to show reduced activation during emotion-semantic processing. Here we used event-related fMRI to compare passive processing of emotion words in comparison to abstract verbs and animal names in typically-developing controls and individuals with ASC. Relatively reduced brain activation in ASC for emotion words, but not matched control words, was found in motor areas and cingulate cortex specifically. The degree of activation evoked by emotion words in the motor system was also associated with the extent of autistic traits as revealed by the Autism Spectrum Quotient. We suggest that hypoactivation of motor and limbic regions for emotion word processing may underlie difficulties in processing emotional language in ASC. The role that sensorimotor systems and their connections might play in the affective and social-communication difficulties in ASC is discussed. PMID:25278250

Distinct summer and winter bacterial communities in the active layer of Svalbard permafrost revealed by DNA- and RNA-based analyses

DEFF Research Database (Denmark)

Schostag, Morten; Stibal, Marek; Jacobsen, Carsten S.

2015-01-01

organic matter on the bacterial communities. The copy number of 16S rRNA genes and transcripts revealed no distinct seasonal changes indicating potential bacterial activity during winter despite soil temperatures well below -10ºC. Multivariate statistical analysis of the bacterial diversity data (DNA......The active layer of soil overlaying permafrost in the Arctic is subjected to dramatic annual changes in temperature and soil chemistry, which likely affect bacterial activity and community structure. We studied seasonal variations in the bacterial community of active layer soil from Svalbard (78º......N) by co-extracting DNA and RNA from 12 soil cores collected monthly over a year. PCR amplicons of 16S rRNA genes (DNA) and reverse transcribed transcripts (cDNA) were quantified and sequenced to test for the effect of low winter temperature and seasonal variation in concentration of easily degradable...

Phosphoproteomic Analysis of KSHV-Infected Cells Reveals Roles of ORF45-Activated RSK during Lytic Replication.

Directory of Open Access Journals (Sweden)

Denis Avey

2015-07-01

Full Text Available Kaposi's Sarcoma-Associated Herpesvirus (KSHV is an oncogenic virus which has adapted unique mechanisms to modulate the cellular microenvironment of its human host. The pathogenesis of KSHV is intimately linked to its manipulation of cellular signaling pathways, including the extracellular signal-regulated kinase (ERK mitogen-activated protein kinase (MAPK pathway. We have previously shown that KSHV ORF45 contributes to the sustained activation of both ERK and p90 ribosomal S6 kinase (RSK, a major functional mediator of ERK/MAPK signaling during KSHV lytic replication. ORF45-activated RSK is required for optimal KSHV lytic gene expression and progeny virion production, though the underlying mechanisms downstream of this activation are still unclear. We hypothesized that the activation of RSK by ORF45 causes differential phosphorylation of cellular and viral substrates, affecting biological processes essential for efficient KSHV lytic replication. Accordingly, we observed widespread and significant differences in protein phosphorylation upon induction of lytic replication. Mass-spectrometry-based phosphoproteomic screening identified putative substrates of ORF45-activated RSK in KSHV-infected cells. Bioinformatic analyses revealed that nuclear proteins, including several transcriptional regulators, were overrepresented among these candidates. We validated the ORF45/RSK-dependent phosphorylation of several putative substrates by employing KSHV BAC mutagenesis, kinase inhibitor treatments, and/or CRISPR-mediated knockout of RSK in KSHV-infected cells. Furthermore, we assessed the consequences of knocking out these substrates on ORF45/RSK-dependent regulation of gene expression and KSHV progeny virion production. Finally, we show data to support that ORF45 regulates the translational efficiency of a subset of viral/cellular genes with complex secondary structure in their 5' UTR. Altogether, these data shed light on the mechanisms by which KSHV ORF45

The Effects of Covert Audio Coaching on the Job Performance of Supported Employees

Science.gov (United States)

Bennett, Kyle; Brady, Michael P.; Scott, Jack; Dukes, Charles; Frain, Michael

2010-01-01

The importance of employment in society is unmistakable, but for many people sustained employment remains elusive. The unemployment rate for individuals with disabilities is staggering, and the consequences of being unemployed affects those individuals, their families, and society. The effects of performance feedback delivered via covert audio…

Indication of a species in an extinction vortex: The ocellated turkey on the Yucatan peninsula, Mexico

NARCIS (Netherlands)

Kampichler, C.; Calmé, S.; Weissenberger, H.; Arriaga-Weiss, S.

2010-01-01

The ocellated turkey Meleagris ocellata (OT) is a large, unmistakable endemic bird of the Yucatan peninsula. The species has suffered a considerable loss of distributional area as well as local abundance between 1980 and 2000 and is classified as endangered according to Mexican norms. We applied

Leśniewski’s Systems and the Aristotelian Model of Science

NARCIS (Netherlands)

Betti, A.; Lapointe, S.; Marion, M.; Miśkiewicz, W.; Woleński, J.

2009-01-01

The systems of Leśniewski, like Frege’s, have an unmistakably old-fashioned flavour. They stand to, say, post-Tarskian, post-Gödelian, post-Hilbertian logic like traditional peasant Tuscan bread soup stands to molecular fusion kitchen. Why is that? According to suggestions recently put forward,

AFRREV LALIGENS

African Journals Online (AJOL)

Toshiba

2014-02-07

Feb 7, 2014 ... unrelenting calls for prioritization of (even if only the leading) native languages in Nigeria, with .... Technically speaking then, orthography is the natural and fundamental .... Areas of interventions need to be identified. Equally ... against the languages of the environment is unmistakable: No Nigerian society ...

Zebrafish Embryonic Lipidomic Analysis Reveals that the Yolk Cell Is Metabolically Active in Processing Lipid

Directory of Open Access Journals (Sweden)

Daniel Fraher

2016-02-01

Full Text Available The role of lipids in providing energy and structural cellular components during vertebrate development is poorly understood. To elucidate these roles further, we visualized lipid deposition and examined expression of key lipid-regulating genes during zebrafish embryogenesis. We also conducted a semiquantitative analysis of lipidomic composition using liquid chromatography (LC-mass spectrometry. Finally, we analyzed processing of boron-dipyrromethene (BODIPY lipid analogs injected into the yolk using thin layer chromatography. Our data reveal that the most abundant lipids in the embryo are cholesterol, phosphatidylcholine, and triglyceride. Moreover, we demonstrate that lipids are processed within the yolk prior to mobilization to the embryonic body. Our data identify a metabolically active yolk and body resulting in a dynamic lipid composition. This provides a foundation for studying lipid biology during normal or pharmacologically compromised embryogenesis.

Data on the effect of conductive hearing loss on auditory and visual cortex activity revealed by intrinsic signal imaging.

Science.gov (United States)

Teichert, Manuel; Bolz, Jürgen

2017-10-01

This data article provides additional data related to the research article entitled "Simultaneous intrinsic signal imaging of auditory and visual cortex reveals profound effects of acute hearing loss on visual processing" (Teichert and Bolz, 2017) [1]. The primary auditory and visual cortex (A1 and V1) of adult male C57BL/6J mice (P120-P240) were mapped simultaneously using intrinsic signal imaging (Kalatsky and Stryker, 2003) [2]. A1 and V1 activity evoked by combined auditory and visual stimulation were measured before and after conductive hearing loss (CHL) induced by bilateral malleus removal. We provide data showing that A1 responsiveness evoked by sounds of different sound pressure levels (SPL) decreased after CHL whereas visually evoked V1 activity increased after this intervention. In addition, we also provide imaging data on percentage of V1 activity increases after CHL compared to pre-CHL.

A Global Genomic Screening Strategy Reveals Diverse Activators of Constitutive Activated Receptor (CAR)

Science.gov (United States)

A comprehensive survey of conditions that activate CAR in the mouse liver has not been carried out but would be useful in understanding their impact on CAR-dependent liver tumor induction. A gene signature dependent on CAR activation was identified by comparing the transcript pr...

Metabolic activity of uncultivated magnetotactic bacteria revealed by NanoSIMS

Science.gov (United States)

He, M.; Zhang, W.; Gu, L.; Pan, Y.; Lin, W.

2017-12-01

Microorganisms that exhibit magnetotaxis behavior, collectively known as the magnetotactic bacteria (MTB), are those whose motility is influenced by the Earth's magnetic field. MTB are a physiologically diverse group of bacteria with a unique feature of intracellular biomineralization of magnetosomes (Fe3O4 and/or Fe3S4) (Bazylinski et al., 2013). However, the ecophysiology of uncultivated MTB, especially those within the Nitrospirae phylum forming hundreds of bullet-shaped magnetite magnetosomes per cell, is still not well characterized (Lin et al., 2014). Nanoscale secondary ion mass spectrometry (NanoSIMS) is a powerful tool for revealing element distribution in nanometer-scale resolution, which opens exciting possibilities for the study of interactions between microorganisms and environments (Gao et al., 2016; Musat et al., 2016). Here we applied NanoSIMS to investigate the dynamics of carbon and nitrogen assimilations in two magnetotactic Nitrospirae populations at single cell level. Our NanoSIMS results confirmed the metabolic potential of Nitrospirae MTB proposed by genomic and metagenomic analysis and provided additional insights into the ecophysiology of uncultivated MTB. This study suggests that NanoSIMS-based analyses are powerful approaches for investigating and characterizing the ecological function of environmental microorganisms. References: Bazylinski D A., Lefèvre, C T., Schüler D., 2013. Magnetotactic Bacteria. 453-494.Lin W, Bazylinski DA, Xiao T, Wu L- F, Pan Y., 2014. Life with compass: diversity and biogeography of magnetotactic bacteria. Environ Microbiol, 16: 1462-2920.Gao D., Huang X., Tao Y., 2016. A critical review of NanoSIMS in analysis of microbial metabolic activities at single-cell level. Crit Rev Biotechnol, 36: 884-890.Musat N., Musat F., Weber PK., Pett-Ridge J., 2016. Tracking microbial interactions with NanoSIMS. Curr Opin Biotechnol, 41: 114-121.

Selective ligand activity at Nur/retinoid X receptor complexes revealed by dimer-specific bioluminescence resonance energy transfer-based sensors

Science.gov (United States)

Giner, Xavier C; Cotnoir-White, David; Mader, Sylvie; Lévesque, Daniel

2017-01-01

Retinoid X receptors (RXR) play a role as master regulators due to their capacity to form heterodimers with other nuclear receptors. Accordingly, retinoid signaling is involved in multiple biological processes, including development, cell differentiation, metabolism and cell death. However, the role and functions of RXR in different heterodimer complexes remain unsolved, mainly because most RXR drugs (called rexinoids) are not selective to specific heterodimer complexes. This also strongly limits the use of rexinoids for specific therapeutic approaches. In order to better characterize rexinoids at specific nuclear receptor complexes, we have developed and optimized luciferase protein complementation-based Bioluminescence Resonance Energy Transfer (BRET) assays, which can directly measure recruitment of a co-activator motif fused to yellow fluorescent protein (YFP) by specific nuclear receptor dimers. To validate the assays, we compared rexinoid modulation of co-activator recruitment by RXR homodimer, and heterodimers Nur77/RXR and Nurr1/RXR. Results reveal that some rexinoids display selective co-activator recruitment activities with homo- or hetero-dimer complexes. In particular, SR11237 (BMS649) has increased potency for recruitment of co-activator motif and transcriptional activity with the Nur77/RXR heterodimer compared to other complexes. This technology should prove useful to identify new compounds with specificity for individual dimeric species formed by nuclear receptors. PMID:26148973

Optogenetic activation of CA1 pyramidal neurons at the dorsal and ventral hippocampus evokes distinct brain-wide responses revealed by mouse fMRI.

Directory of Open Access Journals (Sweden)

Norio Takata

Full Text Available The dorsal and ventral hippocampal regions (dHP and vHP are proposed to have distinct functions. Electrophysiological studies have revealed intra-hippocampal variances along the dorsoventral axis. Nevertheless, the extra-hippocampal influences of dHP and vHP activities remain unclear. In this study, we compared the spatial distribution of brain-wide responses upon dHP or vHP activation and further estimate connection strengths between the dHP and the vHP with corresponding extra-hippocampal areas. To achieve this, we first investigated responses of local field potential (LFP and multi unit activities (MUA upon light stimulation in the hippocampus of an anesthetized transgenic mouse, whose CA1 pyramidal neurons expressed a step-function opsin variant of channelrhodopsin-2 (ChR2. Optogenetic stimulation increased hippocampal LFP power at theta, gamma, and ultra-fast frequency bands, and augmented MUA, indicating light-induced activation of CA1 pyramidal neurons. Brain-wide responses examined using fMRI revealed that optogenetic activation at the dHP or vHP caused blood oxygenation level-dependent (BOLD fMRI signals in situ. Although activation at the dHP induced BOLD responses at the vHP, the opposite was not observed. Outside the hippocampal formation, activation at the dHP, but not the vHP, evoked BOLD responses at the retrosplenial cortex (RSP, which is in line with anatomical evidence. In contrast, BOLD responses at the lateral septum (LS were induced only upon vHP activation, even though both dHP and vHP send axonal fibers to the LS. Our findings suggest that the primary targets of dHP and vHP activation are distinct, which concurs with attributed functions of the dHP and RSP in spatial memory, as well as of the vHP and LS in emotional responses.

10. O Olawoyin John Hick Pluralism in the Traditional Yoruba ...

African Journals Online (AJOL)

REGINALDS

equated with the Yoruba concept of the Supreme Being or Olodumare. ... pluralism should also be distinguished from religious relativism. ... is beyond comprehension and language, and from the culture in which the experiencer ..... being determines the moral issue of life, so that it is unmistakably implied in Yoruba theology ...

The practice of the United Nations in combating terrorism from 1946-2008 : questions of legality and legitimacy

NARCIS (Netherlands)

van Ginkel, B.T.

2010-01-01

Over the last thirty years, the UN has shown an unmistakable interest in combating terrorism. In this study, the practice of the General Assembly and the Security Council in combating terrorism is analysed, in order to answer the question whether these organs, taking into account their powers and

Domain activities of PapC usher reveal the mechanism of action of an Escherichia coli molecular machine.

Science.gov (United States)

Volkan, Ender; Ford, Bradley A; Pinkner, Jerome S; Dodson, Karen W; Henderson, Nadine S; Thanassi, David G; Waksman, Gabriel; Hultgren, Scott J

2012-06-12

P pili are prototypical chaperone-usher pathway-assembled pili used by Gram-negative bacteria to adhere to host tissues. The PapC usher contains five functional domains: a transmembrane β-barrel, a β-sandwich Plug, an N-terminal (periplasmic) domain (NTD), and two C-terminal (periplasmic) domains, CTD1 and CTD2. Here, we delineated usher domain interactions between themselves and with chaperone-subunit complexes and showed that overexpression of individual usher domains inhibits pilus assembly. Prior work revealed that the Plug domain occludes the pore of the transmembrane domain of a solitary usher, but the chaperone-adhesin-bound usher has its Plug displaced from the pore, adjacent to the NTD. We demonstrate an interaction between the NTD and Plug domains that suggests a biophysical basis for usher gating. Furthermore, we found that the NTD exhibits high-affinity binding to the chaperone-adhesin (PapDG) complex and low-affinity binding to the major tip subunit PapE (PapDE). We also demonstrate that CTD2 binds with lower affinity to all tested chaperone-subunit complexes except for the chaperone-terminator subunit (PapDH) and has a catalytic role in dissociating the NTD-PapDG complex, suggesting an interplay between recruitment to the NTD and transfer to CTD2 during pilus initiation. The Plug domain and the NTD-Plug complex bound all of the chaperone-subunit complexes tested including PapDH, suggesting that the Plug actively recruits chaperone-subunit complexes to the usher and is the sole recruiter of PapDH. Overall, our studies reveal the cooperative, active roles played by periplasmic domains of the usher to initiate, grow, and terminate a prototypical chaperone-usher pathway pilus.

Angiogenesis interactome and time course microarray data reveal the distinct activation patterns in endothelial cells.

Directory of Open Access Journals (Sweden)

Liang-Hui Chu

Full Text Available Angiogenesis involves stimulation of endothelial cells (EC by various cytokines and growth factors, but the signaling mechanisms are not completely understood. Combining dynamic gene expression time-course data for stimulated EC with protein-protein interactions associated with angiogenesis (the "angiome" could reveal how different stimuli result in different patterns of network activation and could implicate signaling intermediates as points for control or intervention. We constructed the protein-protein interaction networks of positive and negative regulation of angiogenesis comprising 367 and 245 proteins, respectively. We used five published gene expression datasets derived from in vitro assays using different types of blood endothelial cells stimulated by VEGFA (vascular endothelial growth factor A. We used the Short Time-series Expression Miner (STEM to identify significant temporal gene expression profiles. The statistically significant patterns between 2D fibronectin and 3D type I collagen substrates for telomerase-immortalized EC (TIME show that different substrates could influence the temporal gene activation patterns in the same cell line. We investigated the different activation patterns among 18 transmembrane tyrosine kinase receptors, and experimentally measured the protein level of the tyrosine-kinase receptors VEGFR1, VEGFR2 and VEGFR3 in human umbilical vein EC (HUVEC and human microvascular EC (MEC. The results show that VEGFR1-VEGFR2 levels are more closely coupled than VEGFR1-VEGFR3 or VEGFR2-VEGFR3 in HUVEC and MEC. This computational methodology can be extended to investigate other molecules or biological processes such as cell cycle.

Hydrophilic Phage-Mimicking Membrane Active Antimicrobials Reveal Nanostructure-Dependent Activity and Selectivity.

Science.gov (United States)

Jiang, Yunjiang; Zheng, Wan; Kuang, Liangju; Ma, Hairong; Liang, Hongjun

2017-09-08

The prevalent wisdom on developing membrane active antimicrobials (MAAs) is to seek a delicate, yet unquantified, cationic-hydrophobic balance. Inspired by phages that use nanostructured protein devices to invade bacteria efficiently and selectively, we study here the antibiotic role of nanostructures by designing spherical and rod-like polymer molecular brushes (PMBs) that mimic the two basic structural motifs of bacteriophages. Three model PMBs with different well-defined geometries consisting of multiple, identical copies of densely packed poly(4-vinyl-N-methylpyridine iodide) branches are synthesized by controlled/"living" polymerization, reminiscent of the viral structural motifs comprised of multiple copies of protein subunits. We show that, while the individual linear-chain polymer branch that makes up the PMBs is hydrophilic and a weak antimicrobial, amphiphilicity is not a required antibiotic trait once nanostructures come into play. The nanostructured PMBs induce an unusual topological transition of bacterial but not mammalian membranes to form pores. The sizes and shapes of the nanostructures further help define the antibiotic activity and selectivity of the PMBs against different families of bacteria. This study highlights the importance of nanostructures in the design of MAAs with high activity, low toxicity, and target specificity.

Structure of the CaMKIIdelta/calmodulin complex reveals the molecular mechanism of CaMKII kinase activation.

Directory of Open Access Journals (Sweden)

Peter Rellos

2010-07-01

Full Text Available Long-term potentiation (LTP, a long-lasting enhancement in communication between neurons, is considered to be the major cellular mechanism underlying learning and memory. LTP triggers high-frequency calcium pulses that result in the activation of Calcium/Calmodulin (CaM-dependent kinase II (CaMKII. CaMKII acts as a molecular switch because it remains active for a long time after the return to basal calcium levels, which is a unique property required for CaMKII function. Here we describe the crystal structure of the human CaMKIIdelta/Ca2+/CaM complex, structures of all four human CaMKII catalytic domains in their autoinhibited states, as well as structures of human CaMKII oligomerization domains in their tetradecameric and physiological dodecameric states. All four autoinhibited human CaMKIIs were monomeric in the determined crystal structures but associated weakly in solution. In the CaMKIIdelta/Ca2+/CaM complex, the inhibitory region adopted an extended conformation and interacted with an adjacent catalytic domain positioning T287 into the active site of the interacting protomer. Comparisons with autoinhibited CaMKII structures showed that binding of calmodulin leads to the rearrangement of residues in the active site to a conformation suitable for ATP binding and to the closure of the binding groove for the autoinhibitory helix by helix alphaD. The structural data, together with biophysical interaction studies, reveals the mechanism of CaMKII activation by calmodulin and explains many of the unique regulatory properties of these two essential signaling molecules.This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3-D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the Web plugin are available in Text S1.

Collaborative activity between parietal and dorso-lateral prefrontal cortex in dynamic spatial working memory revealed by fMRI.

Science.gov (United States)

Diwadkar, V A; Carpenter, P A; Just, M A

2000-07-01

Functional MRI was used to determine how the constituents of the cortical network subserving dynamic spatial working memory respond to two types of increases in task complexity. Participants mentally maintained the most recent location of either one or three objects as the three objects moved discretely in either a two- or three-dimensional array. Cortical activation in the dorsolateral prefrontal (DLPFC) and the parietal cortex increased as a function of the number of object locations to be maintained and the dimensionality of the display. An analysis of the response characteristics of the individual voxels showed that a large proportion were activated only when both the variables imposed the higher level of demand. A smaller proportion were activated specifically in response to increases in task demand associated with each of the independent variables. A second experiment revealed the same effect of dimensionality in the parietal cortex when the movement of objects was signaled auditorily rather than visually, indicating that the additional representational demands induced by 3-D space are independent of input modality. The comodulation of activation in the prefrontal and parietal areas by the amount of computational demand suggests that the collaboration between areas is a basic feature underlying much of the functionality of spatial working memory. Copyright 2000 Academic Press.

38 CFR 20.1410 - Rule 1410. Stays pending court action.

Science.gov (United States)

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Rule 1410. Stays pending court action. 20.1410 Section 20.1410 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS... Clear and Unmistakable Error § 20.1410 Rule 1410. Stays pending court action. The Board will stay its...

Leadership and the Millennials: Transforming Today's Technological Teens into Tomorrow's Leaders

Science.gov (United States)

Wisniewski, Mary Ann

2010-01-01

Although older and younger generations unfailingly tend to disagree on values and are inclined to perceive one another with a degree of skepticism and disapproval, it is an unmistakable reality that because of technology today's youth are approaching life differently than previous generations. It is also clear that today's Millennials are…

Transcriptome Analysis Reveals Markers of Aberrantly Activated Innate Immunity in Vitiligo Lesional and Non-Lesional Skin

Science.gov (United States)

Huang, Yuanshen; Wang, Yang; Yu, Jie; Gao, Min; Levings, Megan; Wei, Shencai; Zhang, Shengquan; Xu, Aie; Su, Mingwan; Dutz, Jan; Zhang, Xuejun; Zhou, Youwen

2012-01-01

Background Vitiligo is characterized by the death of melanocytes in the skin. This is associated with the presence of T cell infiltrates in the lesional borders. However, at present, there is no detailed and systematic characterization on whether additional cellular or molecular changes are present inside vitiligo lesions. Further, it is unknown if the normal appearing non-lesional skin of vitiligo patients is in fact normal. The purpose of this study is to systematically characterize the molecular and cellular characteristics of the lesional and non-lesional skin of vitiligo patients. Methods and Materials Paired lesional and non-lesional skin biopsies from twenty-three vitiligo patients and normal skin biopsies from sixteen healthy volunteers were obtained with informed consent. The following aspects were analyzed: (1) transcriptome changes present in vitiligo skin using DNA microarrays and qRT-PCR; (2) abnormal cellular infiltrates in vitiligo skin explant cultures using flow cytometry; and (3) distribution of the abnormal cellular infiltrates in vitiligo skin using immunofluorescence microscopy. Results Compared with normal skin, vitiligo lesional skin contained 17 genes (mostly melanocyte-specific genes) whose expression was decreased or absent. In contrast, the relative expression of 13 genes was up-regulated. The up-regulated genes point to aberrant activity of the innate immune system, especially natural killer cells in vitiligo. Strikingly, the markers of heightened innate immune responses were also found to be up-regulated in the non-lesional skin of vitiligo patients. Conclusions and Clinical Implications As the first systematic transcriptome characterization of the skin in vitiligo patients, this study revealed previously unknown molecular markers that strongly suggest aberrant innate immune activation in the microenvironment of vitiligo skin. Since these changes involve both lesional and non-lesional skin, our results suggest that therapies targeting

Dynamic Response Genes in CD4+ T Cells Reveal a Network of Interactive Proteins that Classifies Disease Activity in Multiple Sclerosis

Directory of Open Access Journals (Sweden)

Sandra Hellberg

2016-09-01

Full Text Available Multiple sclerosis (MS is a chronic inflammatory disease of the CNS and has a varying disease course as well as variable response to treatment. Biomarkers may therefore aid personalized treatment. We tested whether in vitro activation of MS patient-derived CD4+ T cells could reveal potential biomarkers. The dynamic gene expression response to activation was dysregulated in patient-derived CD4+ T cells. By integrating our findings with genome-wide association studies, we constructed a highly connected MS gene module, disclosing cell activation and chemotaxis as central components. Changes in several module genes were associated with differences in protein levels, which were measurable in cerebrospinal fluid and were used to classify patients from control individuals. In addition, these measurements could predict disease activity after 2 years and distinguish low and high responders to treatment in two additional, independent cohorts. While further validation is needed in larger cohorts prior to clinical implementation, we have uncovered a set of potentially promising biomarkers.

Active mechanics in living oocytes reveal molecular-scale force kinetics

Science.gov (United States)

Ahmed, Wylie; Fodor, Etienne; Almonacid, Maria; Bussonnier, Matthias; Verlhac, Marie-Helene; Gov, Nir; Visco, Paolo; van Wijland, Frederic; Betz, Timo

Unlike traditional materials, living cells actively generate forces at the molecular scale that change their structure and mechanical properties. This nonequilibrium activity is essential for cellular function, and drives processes such as cell division. Single molecule studies have uncovered the detailed force kinetics of isolated motor proteins in-vitro, however their behavior in-vivo has been elusive due to the complex environment inside the cell. Here, we quantify active forces and intracellular mechanics in living oocytes using in-vivo optical trapping and laser interferometry of endogenous vesicles. We integrate an experimental and theoretical framework to connect mesoscopic measurements of nonequilibrium properties to the underlying molecular- scale force kinetics. Our results show that force generation by myosin-V drives the cytoplasmic-skeleton out-of-equilibrium (at frequencies below 300 Hz) and actively softens the environment. In vivo myosin-V activity generates a force of F ~ 0 . 4 pN, with a power-stroke of length Δx ~ 20 nm and duration τ ~ 300 μs, that drives vesicle motion at vv ~ 320 nm/s. This framework is widely applicable to characterize living cells and other soft active materials.

Dental Enamel Development: Proteinases and Their Enamel Matrix Substrates

Science.gov (United States)

Bartlett, John D.

2013-01-01

This review focuses on recent discoveries and delves in detail about what is known about each of the proteins (amelogenin, ameloblastin, and enamelin) and proteinases (matrix metalloproteinase-20 and kallikrein-related peptidase-4) that are secreted into the enamel matrix. After an overview of enamel development, this review focuses on these enamel proteins by describing their nomenclature, tissue expression, functions, proteinase activation, and proteinase substrate specificity. These proteins and their respective null mice and human mutations are also evaluated to shed light on the mechanisms that cause nonsyndromic enamel malformations termed amelogenesis imperfecta. Pertinent controversies are addressed. For example, do any of these proteins have a critical function in addition to their role in enamel development? Does amelogenin initiate crystallite growth, does it inhibit crystallite growth in width and thickness, or does it do neither? Detailed examination of the null mouse literature provides unmistakable clues and/or answers to these questions, and this data is thoroughly analyzed. Striking conclusions from this analysis reveal that widely held paradigms of enamel formation are inadequate. The final section of this review weaves the recent data into a plausible new mechanism by which these enamel matrix proteins support and promote enamel development. PMID:24159389

Selective activation of SHP2 activity by cisplatin revealed by a novel chemical probe-based assay

International Nuclear Information System (INIS)

Kuo, Chun-Chen; Chu, Chi-Yuan; Lin, Jing-Jer; Lo, Lee-Chiang

2010-01-01

Src homology-2 (SH2) domain-containing phosphatase 2 (SHP2) is known to participate in several different signaling pathways to mediate cell growth, survival, migration, and differentiation. However, due to the lack of proper analytical tools, it is unclear whether the phosphatase activity of SHP2 is activated in most studies. We have previously developed an activity-based probe LCL2 that formed covalent linkage with catalytically active protein tyrosine phosphatases (PTPs). Here, by combining LCL2 with a SHP2 specific antibody, we established an assay system that enables the direct monitoring of SHP2 activity upon cisplatin treatment of cancer cells. The protocol is advantageous over conventional colorimetric or in-gel PTP assays as it is specific and does not require the use of radioisotope reagents. Using this assay, we found SHP2 activity was selectively activated by cisplatin. Moreover, the activation of SHP2 appeared to be specific for cisplatin as other DNA damage agents failed to activate the activity. Although the role of SHP2 activation by cisplatin treatments is still unclear to us, our results provide the first direct evidence for the activation of SHP2 during cisplatin treatments. More importantly, the concept of using activity-based probe in conjunction with target-specific antibodies could be extended to other enzyme classes.

Oil and Blood in the Niger Delta Area of Nigeria: A Critique of the ...

African Journals Online (AJOL)

Also, the political actors who have been presiding over the affairs of the Nigerian state have succeeded in looting and pilfering the collective wealth generated by the region thereby keeping the people and indeed the entire masses of Nigeria in perpetual poverty while the state itself bears the unmistakably the features of a ...

Linked functional network abnormalities during intrinsic and extrinsic activity in schizophrenia as revealed by a data-fusion approach.

Science.gov (United States)

Hashimoto, Ryu-Ichiro; Itahashi, Takashi; Okada, Rieko; Hasegawa, Sayaka; Tani, Masayuki; Kato, Nobumasa; Mimura, Masaru

2018-01-01

Abnormalities in functional brain networks in schizophrenia have been studied by examining intrinsic and extrinsic brain activity under various experimental paradigms. However, the identified patterns of abnormal functional connectivity (FC) vary depending on the adopted paradigms. Thus, it is unclear whether and how these patterns are inter-related. In order to assess relationships between abnormal patterns of FC during intrinsic activity and those during extrinsic activity, we adopted a data-fusion approach and applied partial least square (PLS) analyses to FC datasets from 25 patients with chronic schizophrenia and 25 age- and sex-matched normal controls. For the input to the PLS analyses, we generated a pair of FC maps during the resting state (REST) and the auditory deviance response (ADR) from each participant using the common seed region in the left middle temporal gyrus, which is a focus of activity associated with auditory verbal hallucinations (AVHs). PLS correlation (PLS-C) analysis revealed that patients with schizophrenia have significantly lower loadings of a component containing positive FCs in default-mode network regions during REST and a component containing positive FCs in the auditory and attention-related networks during ADR. Specifically, loadings of the REST component were significantly correlated with the severities of positive symptoms and AVH in patients with schizophrenia. The co-occurrence of such altered FC patterns during REST and ADR was replicated using PLS regression, wherein FC patterns during REST are modeled to predict patterns during ADR. These findings provide an integrative understanding of altered FCs during intrinsic and extrinsic activity underlying core schizophrenia symptoms.

Multitaxon activity profiling reveals differential microbial response to reduced seawater pH and oil pollution.

Science.gov (United States)

Coelho, Francisco J R C; Cleary, Daniel F R; Costa, Rodrigo; Ferreira, Marina; Polónia, Ana R M; Silva, Artur M S; Simões, Mário M Q; Oliveira, Vanessa; Gomes, Newton C M

2016-09-01

There is growing concern that predicted changes to global ocean chemistry will interact with anthropogenic pollution to significantly alter marine microbial composition and function. However, knowledge of the compounding effects of climate change stressors and anthropogenic pollution is limited. Here, we used 16S and 18S rRNA (cDNA)-based activity profiling to investigate the differential responses of selected microbial taxa to ocean acidification and oil hydrocarbon contamination under controlled laboratory conditions. Our results revealed that a lower relative abundance of sulphate-reducing bacteria (Desulfosarcina/Desulfococcus clade) due to an adverse effect of seawater acidification and oil hydrocarbon contamination (reduced pH-oil treatment) may be coupled to changes in sediment archaeal communities. In particular, we observed a pronounced compositional shift and marked reduction in the prevalence of otherwise abundant operational taxonomic units (OTUs) belonging to the archaeal Marine Benthic Group B and Marine Hydrothermal Vent Group (MHVG) in the reduced pH-oil treatment. Conversely, the abundance of several putative hydrocarbonoclastic fungal OTUs was higher in the reduced pH-oil treatment. Sediment hydrocarbon profiling, furthermore, revealed higher concentrations of several alkanes in the reduced pH-oil treatment, corroborating the functional implications of the structural changes to microbial community composition. Collectively, our results advance the understanding of the response of a complex microbial community to the interaction between reduced pH and anthropogenic pollution. In future acidified marine environments, oil hydrocarbon contamination may alter the typical mixotrophic and k-/r-strategist composition of surface sediment microbiomes towards a more heterotrophic state with lower doubling rates, thereby impairing the ability of the ecosystem to recover from acute oil contamination events. © 2016 John Wiley & Sons Ltd.

When Macbeth becomes scots When Macbeth becomes scots

Directory of Open Access Journals (Sweden)

J. Derrick McClure

2008-04-01

Full Text Available In 1992, two Scots translations of Shakespeare’s Macbeth, by David Purves and Robin L.C. Lorimer, were published almost simultaneously.2 These had been made independently, though each translator was aware of the other’s intention; and they represent two unmistakably different approaches to the project. Before examining the translations themselves, I propose to submit certain assumptions—some almost axiomatic, some perhaps deserving of more detailed consideration—regarding poetic translation, and apply them in turn to the specific question of translating Shakespeare into Scots. In 1992, two Scots translations of Shakespeare’s Macbeth, by David Purves and Robin L.C. Lorimer, were published almost simultaneously.2 These had been made independently, though each translator was aware of the other’s intention; and they represent two unmistakably different approaches to the project. Before examining the translations themselves, I propose to submit certain assumptions—some almost axiomatic, some perhaps deserving of more detailed consideration—regarding poetic translation, and apply them in turn to the specific question of translating Shakespeare into Scots.

Metatranscriptomics reveals overall active bacterial composition in caries lesions

Directory of Open Access Journals (Sweden)

Aurea Simón-Soro

2014-10-01

Full Text Available Background: Identifying the microbial species in caries lesions is instrumental to determine the etiology of dental caries. However, a significant proportion of bacteria in carious lesions have not been cultured, and the use of molecular methods has been limited to DNA-based approaches, which detect both active and inactive or dead microorganisms. Objective: To identify the RNA-based, metabolically active bacterial composition of caries lesions at different stages of disease progression in order to provide a list of potential etiological agents of tooth decay. Design: Non-cavitated enamel caries lesions (n=15 and dentin caries lesions samples (n=12 were collected from 13 individuals. RNA was extracted and cDNA was constructed, which was used to amplify the 16S rRNA gene. The resulting 780 bp polymerase chain reaction products were pyrosequenced using Titanium-plus chemistry, and the sequences obtained were used to determine the bacterial composition. Results: A mean of 4,900 sequences of the 16S rRNA gene with an average read length of 661 bp was obtained per sample, giving a comprehensive view of the active bacterial communities in caries lesions. Estimates of bacterial diversity indicate that the microbiota of cavities is highly complex, each sample containing between 70 and 400 metabolically active species. The composition of these bacterial consortia varied among individuals and between caries lesions of the same individuals. In addition, enamel and dentin lesions had a different bacterial makeup. Lactobacilli were found almost exclusively in dentin cavities. Streptococci accounted for 40% of the total active community in enamel caries, and 20% in dentin caries. However, Streptococcus mutans represented only 0.02–0.73% of the total bacterial community. Conclusions: The data indicate that the etiology of dental caries is tissue dependent and that the disease has a clear polymicrobial origin. The low proportion of mutans streptococci

Presbycusis Disrupts Spontaneous Activity Revealed by Resting-State Functional MRI

Directory of Open Access Journals (Sweden)

Yu-Chen Chen

2018-03-01

Full Text Available Purpose: Presbycusis, age-related hearing loss, is believed to involve neural changes in the central nervous system, which is associated with an increased risk of cognitive impairment. The goal of this study was to determine if presbycusis disrupted spontaneous neural activity in specific brain areas involved in auditory processing, attention and cognitive function using resting-state functional magnetic resonance imaging (fMRI approach.Methods: Hearing and resting-state fMRI measurements were obtained from 22 presbycusis patients and 23 age-, sex- and education-matched healthy controls. To identify changes in spontaneous neural activity associated with age-related hearing loss, we compared the amplitude of low-frequency fluctuations (ALFF and regional homogeneity (ReHo of fMRI signals in presbycusis patients vs. controls and then determined if these changes were linked to clinical measures of presbycusis.Results: Compared with healthy controls, presbycusis patients manifested decreased spontaneous activity mainly in the superior temporal gyrus (STG, parahippocampal gyrus (PHG, precuneus and inferior parietal lobule (IPL as well as increased neural activity in the middle frontal gyrus (MFG, cuneus and postcentral gyrus (PoCG. A significant negative correlation was observed between ALFF/ReHo activity in the STG and average hearing thresholds in presbycusis patients. Increased ALFF/ReHo activity in the MFG was positively correlated with impaired Trail-Making Test B (TMT-B scores, indicative of impaired cognitive function involving the frontal lobe.Conclusions: Presbycusis patients have disrupted spontaneous neural activity reflected by ALFF and ReHo measurements in several brain regions; these changes are associated with specific cognitive performance and speech/language processing. These findings mainly emphasize the crucial role of aberrant resting-state ALFF/ReHo patterns in presbycusis patients and will lead to a better understanding of the

Presbycusis Disrupts Spontaneous Activity Revealed by Resting-State Functional MRI.

Science.gov (United States)

Chen, Yu-Chen; Chen, Huiyou; Jiang, Liang; Bo, Fan; Xu, Jin-Jing; Mao, Cun-Nan; Salvi, Richard; Yin, Xindao; Lu, Guangming; Gu, Jian-Ping

2018-01-01

Purpose : Presbycusis, age-related hearing loss, is believed to involve neural changes in the central nervous system, which is associated with an increased risk of cognitive impairment. The goal of this study was to determine if presbycusis disrupted spontaneous neural activity in specific brain areas involved in auditory processing, attention and cognitive function using resting-state functional magnetic resonance imaging (fMRI) approach. Methods : Hearing and resting-state fMRI measurements were obtained from 22 presbycusis patients and 23 age-, sex- and education-matched healthy controls. To identify changes in spontaneous neural activity associated with age-related hearing loss, we compared the amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo) of fMRI signals in presbycusis patients vs. controls and then determined if these changes were linked to clinical measures of presbycusis. Results : Compared with healthy controls, presbycusis patients manifested decreased spontaneous activity mainly in the superior temporal gyrus (STG), parahippocampal gyrus (PHG), precuneus and inferior parietal lobule (IPL) as well as increased neural activity in the middle frontal gyrus (MFG), cuneus and postcentral gyrus (PoCG). A significant negative correlation was observed between ALFF/ReHo activity in the STG and average hearing thresholds in presbycusis patients. Increased ALFF/ReHo activity in the MFG was positively correlated with impaired Trail-Making Test B (TMT-B) scores, indicative of impaired cognitive function involving the frontal lobe. Conclusions : Presbycusis patients have disrupted spontaneous neural activity reflected by ALFF and ReHo measurements in several brain regions; these changes are associated with specific cognitive performance and speech/language processing. These findings mainly emphasize the crucial role of aberrant resting-state ALFF/ReHo patterns in presbycusis patients and will lead to a better understanding of the

Sequencing the extrachromosomal circular mobilome reveals retrotransposon activity in plants.

Directory of Open Access Journals (Sweden)

Sophie Lanciano

2017-02-01

Full Text Available Retrotransposons are mobile genetic elements abundant in plant and animal genomes. While efficiently silenced by the epigenetic machinery, they can be reactivated upon stress or during development. Their level of transcription not reflecting their transposition ability, it is thus difficult to evaluate their contribution to the active mobilome. Here we applied a simple methodology based on the high throughput sequencing of extrachromosomal circular DNA (eccDNA forms of active retrotransposons to characterize the repertoire of mobile retrotransposons in plants. This method successfully identified known active retrotransposons in both Arabidopsis and rice material where the epigenome is destabilized. When applying mobilome-seq to developmental stages in wild type rice, we identified PopRice as a highly active retrotransposon producing eccDNA forms in the wild type endosperm. The mobilome-seq strategy opens new routes for the characterization of a yet unexplored fraction of plant genomes.

Sequencing the extrachromosomal circular mobilome reveals retrotransposon activity in plants.

Science.gov (United States)

Lanciano, Sophie; Carpentier, Marie-Christine; Llauro, Christel; Jobet, Edouard; Robakowska-Hyzorek, Dagmara; Lasserre, Eric; Ghesquière, Alain; Panaud, Olivier; Mirouze, Marie

2017-02-01

Retrotransposons are mobile genetic elements abundant in plant and animal genomes. While efficiently silenced by the epigenetic machinery, they can be reactivated upon stress or during development. Their level of transcription not reflecting their transposition ability, it is thus difficult to evaluate their contribution to the active mobilome. Here we applied a simple methodology based on the high throughput sequencing of extrachromosomal circular DNA (eccDNA) forms of active retrotransposons to characterize the repertoire of mobile retrotransposons in plants. This method successfully identified known active retrotransposons in both Arabidopsis and rice material where the epigenome is destabilized. When applying mobilome-seq to developmental stages in wild type rice, we identified PopRice as a highly active retrotransposon producing eccDNA forms in the wild type endosperm. The mobilome-seq strategy opens new routes for the characterization of a yet unexplored fraction of plant genomes.

Gene expression analysis after receptor tyrosine kinase activation reveals new potential melanoma proteins

International Nuclear Information System (INIS)

Teutschbein, Janka; Haydn, Johannes M; Samans, Birgit; Krause, Michael; Eilers, Martin; Schartl, Manfred; Meierjohann, Svenja

2010-01-01

Melanoma is an aggressive tumor with increasing incidence. To develop accurate prognostic markers and targeted therapies, changes leading to malignant transformation of melanocytes need to be understood. In the Xiphophorus melanoma model system, a mutated version of the EGF receptor Xmrk (Xiphophorus melanoma receptor kinase) triggers melanomagenesis. Cellular events downstream of Xmrk, such as the activation of Akt, Ras, B-Raf or Stat5, were also shown to play a role in human melanomagenesis. This makes the elucidation of Xmrk downstream targets a useful method for identifying processes involved in melanoma formation. Here, we analyzed Xmrk-induced gene expression using a microarray approach. Several highly expressed genes were confirmed by realtime PCR, and pathways responsible for their induction were revealed using small molecule inhibitors. The expression of these genes was also monitored in human melanoma cell lines, and the target gene FOSL1 was knocked down by siRNA. Proliferation and migration of siRNA-treated melanoma cell lines were then investigated. Genes with the strongest upregulation after receptor activation were FOS-like antigen 1 (Fosl1), early growth response 1 (Egr1), osteopontin (Opn), insulin-like growth factor binding protein 3 (Igfbp3), dual-specificity phosphatase 4 (Dusp4), and tumor-associated antigen L6 (Taal6). Interestingly, most genes were blocked in presence of a SRC kinase inhibitor. Importantly, we found that FOSL1, OPN, IGFBP3, DUSP4, and TAAL6 also exhibited increased expression levels in human melanoma cell lines compared to human melanocytes. Knockdown of FOSL1 in human melanoma cell lines reduced their proliferation and migration. Altogether, the data show that the receptor tyrosine kinase Xmrk is a useful tool in the identification of target genes that are commonly expressed in Xmrk-transgenic melanocytes and melanoma cell lines. The identified molecules constitute new possible molecular players in melanoma development

Gene expression analysis after receptor tyrosine kinase activation reveals new potential melanoma proteins

Directory of Open Access Journals (Sweden)

Krause Michael

2010-07-01

Full Text Available Abstract Background Melanoma is an aggressive tumor with increasing incidence. To develop accurate prognostic markers and targeted therapies, changes leading to malignant transformation of melanocytes need to be understood. In the Xiphophorus melanoma model system, a mutated version of the EGF receptor Xmrk (Xiphophorus melanoma receptor kinase triggers melanomagenesis. Cellular events downstream of Xmrk, such as the activation of Akt, Ras, B-Raf or Stat5, were also shown to play a role in human melanomagenesis. This makes the elucidation of Xmrk downstream targets a useful method for identifying processes involved in melanoma formation. Methods Here, we analyzed Xmrk-induced gene expression using a microarray approach. Several highly expressed genes were confirmed by realtime PCR, and pathways responsible for their induction were revealed using small molecule inhibitors. The expression of these genes was also monitored in human melanoma cell lines, and the target gene FOSL1 was knocked down by siRNA. Proliferation and migration of siRNA-treated melanoma cell lines were then investigated. Results Genes with the strongest upregulation after receptor activation were FOS-like antigen 1 (Fosl1, early growth response 1 (Egr1, osteopontin (Opn, insulin-like growth factor binding protein 3 (Igfbp3, dual-specificity phosphatase 4 (Dusp4, and tumor-associated antigen L6 (Taal6. Interestingly, most genes were blocked in presence of a SRC kinase inhibitor. Importantly, we found that FOSL1, OPN, IGFBP3, DUSP4, and TAAL6 also exhibited increased expression levels in human melanoma cell lines compared to human melanocytes. Knockdown of FOSL1 in human melanoma cell lines reduced their proliferation and migration. Conclusion Altogether, the data show that the receptor tyrosine kinase Xmrk is a useful tool in the identification of target genes that are commonly expressed in Xmrk-transgenic melanocytes and melanoma cell lines. The identified molecules constitute

Metagenomics, metatranscriptomics and single cell genomics reveal functional response of active Oceanospirillales to Gulf oil spill

Energy Technology Data Exchange (ETDEWEB)

Mason, Olivia U.; Hazen, Terry C.; Borglin, Sharon; Chain, Patrick S. G.; Dubinsky, Eric A.; Fortney, Julian L.; Han, James; Holman, Hoi-Ying N.; Hultman, Jenni; Lamendella, Regina; Mackelprang, Rachel; Malfatti, Stephanie; Tom, Lauren M.; Tringe, Susannah G.; Woyke, Tanja; Zhou, Jizhong; Rubin, Edward M.; Jansson, Janet K.

2012-06-12

The Deepwater Horizon oil spill in the Gulf of Mexico resulted in a deep-sea hydrocarbon plume that caused a shift in the indigenous microbial community composition with unknown ecological consequences. Early in the spill history, a bloom of uncultured, thus uncharacterized, members of the Oceanospirillales was previously detected, but their role in oil disposition was unknown. Here our aim was to determine the functional role of the Oceanospirillales and other active members of the indigenous microbial community using deep sequencing of community DNA and RNA, as well as single-cell genomics. Shotgun metagenomic and metatranscriptomic sequencing revealed that genes for motility, chemotaxis and aliphatic hydrocarbon degradation were significantly enriched and expressed in the hydrocarbon plume samples compared with uncontaminated seawater collected from plume depth. In contrast, although genes coding for degradation of more recalcitrant compounds, such as benzene, toluene, ethylbenzene, total xylenes and polycyclic aromatic hydrocarbons, were identified in the metagenomes, they were expressed at low levels, or not at all based on analysis of the metatranscriptomes. Isolation and sequencing of two Oceanospirillales single cells revealed that both cells possessed genes coding for n-alkane and cycloalkane degradation. Specifically, the near-complete pathway for cyclohexane oxidation in the Oceanospirillales single cells was elucidated and supported by both metagenome and metatranscriptome data. The draft genome also included genes for chemotaxis, motility and nutrient acquisition strategies that were also identified in the metagenomes and metatranscriptomes. These data point towards a rapid response of members of the Oceanospirillales to aliphatic hydrocarbons in the deep sea.

Active nuclear transcriptome analysis reveals inflammasome-dependent mechanism for early neutrophil response to Mycobacterium marinum.

Science.gov (United States)

Kenyon, Amy; Gavriouchkina, Daria; Zorman, Jernej; Napolitani, Giorgio; Cerundolo, Vincenzo; Sauka-Spengler, Tatjana

2017-07-26

The mechanisms governing neutrophil response to Mycobacterium tuberculosis remain poorly understood. In this study we utilise biotagging, a novel genome-wide profiling approach based on cell type-specific in vivo biotinylation in zebrafish to analyse the initial response of neutrophils to Mycobacterium marinum, a close genetic relative of M. tuberculosis used to model tuberculosis. Differential expression analysis following nuclear RNA-seq of neutrophil active transcriptomes reveals a significant upregulation in both damage-sensing and effector components of the inflammasome, including caspase b, NLRC3 ortholog (wu: fb15h11) and il1β. Crispr/Cas9-mediated knockout of caspase b, which acts by proteolytic processing of il1β, results in increased bacterial burden and less infiltration of macrophages to sites of mycobacterial infection, thus impairing granuloma development. We also show that a number of immediate early response genes (IEGs) are responsible for orchestrating the initial neutrophil response to mycobacterial infection. Further perturbation of the IEGs exposes egr3 as a key transcriptional regulator controlling il1β transcription.

Microfabricated microbial fuel cell arrays reveal electrochemically active microbes.

Directory of Open Access Journals (Sweden)

Huijie Hou

Full Text Available Microbial fuel cells (MFCs are remarkable "green energy" devices that exploit microbes to generate electricity from organic compounds. MFC devices currently being used and studied do not generate sufficient power to support widespread and cost-effective applications. Hence, research has focused on strategies to enhance the power output of the MFC devices, including exploring more electrochemically active microbes to expand the few already known electricigen families. However, most of the MFC devices are not compatible with high throughput screening for finding microbes with higher electricity generation capabilities. Here, we describe the development of a microfabricated MFC array, a compact and user-friendly platform for the identification and characterization of electrochemically active microbes. The MFC array consists of 24 integrated anode and cathode chambers, which function as 24 independent miniature MFCs and support direct and parallel comparisons of microbial electrochemical activities. The electricity generation profiles of spatially distinct MFC chambers on the array loaded with Shewanella oneidensis MR-1 differed by less than 8%. A screen of environmental microbes using the array identified an isolate that was related to Shewanella putrefaciens IR-1 and Shewanella sp. MR-7, and displayed 2.3-fold higher power output than the S. oneidensis MR-1 reference strain. Therefore, the utility of the MFC array was demonstrated.

Bcl2-associated Athanogene 3 Interactome Analysis Reveals a New Role in Modulating Proteasome Activity*

Science.gov (United States)

Chen, Ying; Yang, Li-Na; Cheng, Li; Tu, Shun; Guo, Shu-Juan; Le, Huang-Ying; Xiong, Qian; Mo, Ran; Li, Chong-Yang; Jeong, Jun-Seop; Jiang, Lizhi; Blackshaw, Seth; Bi, Li-Jun; Zhu, Heng; Tao, Sheng-Ce; Ge, Feng

2013-01-01

Bcl2-associated athanogene 3 (BAG3), a member of the BAG family of co-chaperones, plays a critical role in regulating apoptosis, development, cell motility, autophagy, and tumor metastasis and in mediating cell adaptive responses to stressful stimuli. BAG3 carries a BAG domain, a WW domain, and a proline-rich repeat (PXXP), all of which mediate binding to different partners. To elucidate BAG3's interaction network at the molecular level, we employed quantitative immunoprecipitation combined with knockdown and human proteome microarrays to comprehensively profile the BAG3 interactome in humans. We identified a total of 382 BAG3-interacting proteins with diverse functions, including transferase activity, nucleic acid binding, transcription factors, proteases, and chaperones, suggesting that BAG3 is a critical regulator of diverse cellular functions. In addition, we characterized interactions between BAG3 and some of its newly identified partners in greater detail. In particular, bioinformatic analysis revealed that the BAG3 interactome is strongly enriched in proteins functioning within the proteasome-ubiquitination process and that compose the proteasome complex itself, suggesting that a critical biological function of BAG3 is associated with the proteasome. Functional studies demonstrated that BAG3 indeed interacts with the proteasome and modulates its activity, sustaining cell survival and underlying resistance to therapy through the down-modulation of apoptosis. Taken as a whole, this study expands our knowledge of the BAG3 interactome, provides a valuable resource for understanding how BAG3 affects different cellular functions, and demonstrates that biologically relevant data can be harvested using this kind of integrated approach. PMID:23824909

Proteomics analysis of dendritic cell activation by contact allergens reveals possible biomarkers regulated by Nrf2

Energy Technology Data Exchange (ETDEWEB)

Mussotter, Franz, E-mail: franz.mussotter@bfr.bund.de [German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin (Germany); Tomm, Janina Melanie [Helmholtz Centre for Environmental Research (UFZ), Department of Molecular Systems Biology, Leipzig (Germany); El Ali, Zeina; Pallardy, Marc; Kerdine-Römer, Saadia [INSERM UMR 996, Univ Paris-Sud, Université Paris-Saclay, Chátenay-Malabry (France); Götz, Mario [German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin (Germany); Bergen, Martin von [Helmholtz Centre for Environmental Research (UFZ), Department of Molecular Systems Biology, Leipzig (Germany); University of Leipzig, Institute of Biochemistry, Leipzig (Germany); Aalborg University, Department of Chemistry and Bioscience, Aalborg (Denmark); Haase, Andrea; Luch, Andreas [German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin (Germany)

2016-12-15

Allergic contact dermatitis is a widespread disease with high clinical relevance affecting approximately 20% of the general population. Typically, contact allergens are low molecular weight electrophilic compounds which can activate the Keap1/Nrf2 pathway. We performed a proteomics study to reveal possible biomarkers for dendritic cell (DC) activation by contact allergens and to further elucidate the role of Keap1/Nrf2 signaling in this process. We used bone marrow derived dendritic cells (BMDCs) of wild-type (nrf2{sup +/+}) and Nrf2 knockout (nrf2{sup −/−}) mice and studied their response against the model contact sensitizers 2,4-dinitrochlorobenzene (DNCB), cinnamaldehyde (CA) and nickel(II) sulfate by 2-dimensional polyacrylamide gel electrophoresis (2D-PAGE) in combination with electrospray ionization tandem mass spectrometry (ESI-MS/MS). Sodium dodecyl sulfate (SDS, 100 μM) served as irritant control. While treatment with nickel(II) sulfate and SDS had only little effects, CA and DNCB led to significant changes in protein expression. We found 18 and 30 protein spots up-regulated in wild-type cells treated with 50 and 100 μM CA, respectively. For 5 and 10 μM DNCB, 32 and 37 spots were up-regulated, respectively. Almost all of these proteins were not differentially expressed in nrf2{sup −/−} BMDCs, indicating an Nrf2-dependent regulation. Among them proteins were detected which are involved in oxidative stress and heat shock responses, as well as in signal transduction or basic cellular pathways. The applied approach allowed us to differentiate between Nrf2-dependent and Nrf2-independent cellular biomarkers differentially regulated upon allergen-induced DC activation. The data presented might contribute to the further development of suitable in vitro testing methods for chemical-mediated sensitization. - Highlights: • Contact allergens induce proteins involved in DC maturation Nrf2-dependently. • Induction of these proteins points to a functional

Mechanistic studies of anticancer aptamer AS1411 reveal a novel role for nucleolin in regulating Rac1 activation.

Science.gov (United States)

Reyes-Reyes, E Merit; Šalipur, Francesca R; Shams, Mitra; Forsthoefel, Matthew K; Bates, Paula J

2015-08-01

AS1411 is a G-rich quadruplex-forming oligodeoxynucleotide that binds specifically to nucleolin, a protein found on the surface and in the cytoplasm of most malignant cells but absent from the surface/cytoplasm of most normal cells. AS1411 has shown promising clinical activity and is being widely used as a tumor-targeting agent, but its mechanism of action is not fully understood. Previously, we showed that AS1411 is taken up in cancer cells by macropinocytosis (fluid phase endocytosis) and subsequently stimulates further macropinocytosis by a nucleolin-dependent mechanism. In the current study, we have investigated the significance and molecular mechanisms of AS1411-induced macropinocytosis. Our results indicate that the antiproliferative activity of AS1411 in various cell lines correlated with its capacity to stimulate macropinocytosis. In DU145 prostate cancer cells, AS1411 induced activation of EGFR, Akt, p38, and Rac1. Activation of Akt and p38 were not critical for AS1411 activity because Akt activation was not observed in all AS1411-responsive cell lines and knockdown of p38 had no effect on AS1411's ability to inhibit proliferation. On the other hand, activation of EGFR and Rac1 appeared to play a role in AS1411 activity in all cancer cell lines examined (DU145, MDA-MB-468, A549, LNCaP) and their inhibition significantly reduced AS1411-mediated macropinocytosis and AS1411 antiproliferative activity. Interestingly, downregulation of nucleolin expression by siRNA also produced a substantial increase in activated Rac1, revealing a previously unknown role for nucleolin as a negative regulator of Rac1 activation. Our results are consistent with a model whereby AS1411 binding to nucleolin leads to sustained activation of Rac1 and causes methuosis, a novel type of nonapoptotic cell death characterized by hyperstimulation of macropinocytosis. We speculate that methuosis is a tumor/metastasis suppressor mechanism that opposes the malignant functions of Rac1 and that

Structure of unliganded HSV gD reveals a mechanism for receptor-mediated activation of virus entry

Energy Technology Data Exchange (ETDEWEB)

Krummenacher, Claude; Supekar, Vinit M.; Whitbeck, J. Charles; Lazear, Eric; Connolly, Sarah A.; Eisenberg, Roselyn J.; Cohen, Gary H.; Wiley, Don C.; Carfi, Andrea (UPENN); (IRBM); (CHLMM)

2010-07-19

Herpes simplex virus (HSV) entry into cells requires binding of the envelope glycoprotein D (gD) to one of several cell surface receptors. The 50 C-terminal residues of the gD ectodomain are essential for virus entry, but not for receptor binding. We have determined the structure of an unliganded gD molecule that includes these C-terminal residues. The structure reveals that the C-terminus is anchored near the N-terminal region and masks receptor-binding sites. Locking the C-terminus in the position observed in the crystals by an intramolecular disulfide bond abolished receptor binding and virus entry, demonstrating that this region of gD moves upon receptor binding. Similarly, a point mutant that would destabilize the C-terminus structure was nonfunctional for entry, despite increased affinity for receptors. We propose that a controlled displacement of the gD C-terminus upon receptor binding is an essential feature of HSV entry, ensuring the timely activation of membrane fusion.

Revealing hidden effect of earthworm on C distribution and enzyme activity

Science.gov (United States)

Razavi, Bahar S.; Hoang, Duyen; Kuzyakov, Yakov

2017-04-01

Despite its importance for terrestrial nutrient and carbon cycling, the spatial organization and localization of microbial activity in soil and in biopores is poorly understood. We hypothesized that biopores created by earthworm play a critical role in reducing the gap of SOM input and microbial activities between topsoil and subsoil. Accordingly, Carbon (C) allocation by earthworms was related to enzyme distribution along soil profile. For the first time we visualized spatial distribution of enzyme activities (β-glucosidase, chitinase and acid phosphatase) and C allocation (by 14C imaging) in earthworm biopores in topsoil and subsoil. Soil zymography (an in situ method for the analysis of the two-dimensional distribution of enzyme activity in soil) was accompanied with 14C imaging (a method that enables to trace distribution of litter and C in soil profile) to visualize change of enzyme activities along with SOM incorporation by earthworms from topsoil to subsoil. Experiment was set up acquiring rhizoboxes (9×1×50 cm) filled up with fresh soil and 3 earthworms (L. terrestris), which were then layered with 14C-labeled plant-litter of 0.3 MBq on the soil surface. 14C imaging and zymography have been carried out after one month. Activities of all enzymes regardless of their nutrient involvement (C, N, P) were higher in the biopores than in bulk soil, but the differences were larger in topsoil compared to subsoil. Among three enzymes, Phosphatase activity was 4-times higher in the biopore than in the bulk soil. Phosphatase activity was closely associated with edge of burrows and correlate positively with 14C activity. These results emphasized especial contribution of hotspheres such as biopores to C allocation in subsoil - which is limited in C input and nutrients - and in stimulation of microbial and enzymatic activity by input of organic residues, e.g. by earthworms. In conclusion, biopore increased enzymatic mobilization of nutrients (e.g. P) inducing allocation

From Blame to Punishment: Disrupting Prefrontal Cortex Activity Reveals Norm Enforcement Mechanisms.

Science.gov (United States)

Buckholtz, Joshua W; Martin, Justin W; Treadway, Michael T; Jan, Katherine; Zald, David H; Jones, Owen; Marois, René

2015-09-23

The social welfare provided by cooperation depends on the enforcement of social norms. Determining blameworthiness and assigning a deserved punishment are two cognitive cornerstones of norm enforcement. Although prior work has implicated the dorsolateral prefrontal cortex (DLPFC) in norm-based judgments, the relative contribution of this region to blameworthiness and punishment decisions remains poorly understood. Here, we used repetitive transcranial magnetic stimulation (rTMS) and fMRI to determine the specific role of DLPFC function in norm-enforcement behavior. DLPFC rTMS reduced punishment for wrongful acts without affecting blameworthiness ratings, and fMRI revealed punishment-selective DLPFC recruitment, suggesting that these two facets of norm-based decision making are neurobiologically dissociable. Finally, we show that DLPFC rTMS affects punishment decision making by altering the integration of information about culpability and harm. Together, these findings reveal a selective, causal role for DLPFC in norm enforcement: representational integration of the distinct information streams used to make punishment decisions. Copyright © 2015 Elsevier Inc. All rights reserved.

Active Tectonics Revealed by River Profiles along the Puqu Fault

Directory of Open Access Journals (Sweden)

Ping Lu

2015-04-01

Full Text Available The Puqu Fault is situated in Southern Tibet. It is influenced by the eastward extrusion of Northern Tibet and carries the clockwise rotation followed by the southward extrusion. Thus, the Puqu Fault is bounded by the principal dynamic zones and the tectonic evolution remains active alongside. This study intends to understand the tectonic activity in the Puqu Fault Region from the river profiles obtained from the remotely sensed satellite imagery. A medium resolution Digital Elevation Model (DEM, 20 m was generated from an Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER stereo pair of images and the stream network in this region was extracted from this DEM. The indices of slope and drainage area were subsequently calculated from this ASTER DEM. Based on the stream power law, the area-slope plots of the streams were delineated to derive the indices of channel concavity and steepness, which are closely related to tectonic activity. The results show the active tectonics varying significantly along the Puqu Fault, although the potential influence of glaciations may exist. These results are expected to be useful for a better understanding of tectonic evolution in Southeastern Tibet.

CRISPR/Cas9 and active genetics-based trans-species replacement of the endogenous Drosophila kni-L2 CRM reveals unexpected complexity.

Science.gov (United States)

Xu, Xiang-Ru Shannon; Gantz, Valentino Matteo; Siomava, Natalia; Bier, Ethan

2017-12-23

The knirps ( kni ) locus encodes transcription factors required for induction of the L2 wing vein in Drosophila . Here, we employ diverse CRISPR/Cas9 genome editing tools to generate a series of targeted lesions within the endogenous cis-regulatory module (CRM) required for kni expression in the L2 vein primordium. Phenotypic analysis of these ' in locus ' mutations based on both expression of Kni protein and adult wing phenotypes, reveals novel unexpected features of L2-CRM function including evidence for a chromosome pairing-dependent process that promotes transcription. We also demonstrate that self-propagating active genetic elements (CopyCat elements) can efficiently delete and replace the L2-CRM with orthologous sequences from other divergent fly species. Wing vein phenotypes resulting from these trans-species enhancer replacements parallel features of the respective donor fly species. This highly sensitive phenotypic readout of enhancer function in a native genomic context reveals novel features of CRM function undetected by traditional reporter gene analysis. © 2017, Xu et al.

Characterization of the biocontrol activity of pseudomonas fluorescens strain X reveals novel genes regulated by glucose.

Directory of Open Access Journals (Sweden)

Gerasimos F Kremmydas

Full Text Available Pseudomonas fluorescens strain X, a bacterial isolate from the rhizosphere of bean seedlings, has the ability to suppress damping-off caused by the oomycete Pythium ultimum. To determine the genes controlling the biocontrol activity of strain X, transposon mutagenesis, sequencing and complementation was performed. Results indicate that, biocontrol ability of this isolate is attributed to gcd gene encoding glucose dehydrogenase, genes encoding its co-enzyme pyrroloquinoline quinone (PQQ, and two genes (sup5 and sup6 which seem to be organized in a putative operon. This operon (named supX consists of five genes, one of which encodes a non-ribosomal peptide synthase. A unique binding site for a GntR-type transcriptional factor is localized upstream of the supX putative operon. Synteny comparison of the genes in supX revealed that they are common in the genus Pseudomonas, but with a low degree of similarity. supX shows high similarity only to the mangotoxin operon of Ps. syringae pv. syringae UMAF0158. Quantitative real-time PCR analysis indicated that transcription of supX is strongly reduced in the gcd and PQQ-minus mutants of Ps. fluorescens strain X. On the contrary, transcription of supX in the wild type is enhanced by glucose and transcription levels that appear to be higher during the stationary phase. Gcd, which uses PQQ as a cofactor, catalyses the oxidation of glucose to gluconic acid, which controls the activity of the GntR family of transcriptional factors. The genes in the supX putative operon have not been implicated before in the biocontrol of plant pathogens by pseudomonads. They are involved in the biosynthesis of an antimicrobial compound by Ps. fluorescens strain X and their transcription is controlled by glucose, possibly through the activity of a GntR-type transcriptional factor binding upstream of this putative operon.

Sequencing the extrachromosomal circular mobilome reveals retrotransposon activity in plants

OpenAIRE

Lanciano, Sophie; Carpentier, M. C.; Llauro, C.; Jobet, E.; Robakowska-Hyzorek, D.; Lasserre, E.; Ghesquière, Alain; Panaud, O.; Mirouze, Marie

2017-01-01

Retrotransposons are mobile genetic elements abundant in plant and animal genomes. While efficiently silenced by the epigenetic machinery, they can be reactivated upon stress or during development. Their level of transcription not reflecting their transposition ability, it is thus difficult to evaluate their contribution to the active mobilome. Here we applied a simple methodology based on the high throughput sequencing of extrachromosomal circular DNA (eccDNA) forms of active retrotransposon...

Structural Snapshots of an Engineered Cystathionine-γ-lyase Reveal the Critical Role of Electrostatic Interactions in the Active Site

Energy Technology Data Exchange (ETDEWEB)

Yan, Wupeng; Stone, Everett; Zhang, Yan Jessie

2017-02-01

Enzyme therapeutics that can degrade l-methionine (l-Met) are of great interest as numerous malignancies are exquisitely sensitive to l-Met depletion. To exhaust the pool of methionine in human serum, we previously engineered an l-Met-degrading enzyme based on the human cystathionine-γ-lyase scaffold (hCGL-NLV) to circumvent immunogenicity and stability issues observed in the preclinical application of bacterially derived methionine-γ-lyases. To gain further insights into the structure–activity relationships governing the chemistry of the hCGL-NLV lead molecule, we undertook a biophysical characterization campaign that captured crystal structures (2.2 Å) of hCGL-NLV with distinct reaction intermediates, including internal aldimine, substrate-bound, gem-diamine, and external aldimine forms. Curiously, an alternate form of hCGL-NLV that crystallized under higher-salt conditions revealed a locally unfolded active site, correlating with inhibition of activity as a function of ionic strength. Subsequent mutational and kinetic experiments pinpointed that a salt bridge between the phosphate of the essential cofactor pyridoxal 5'-phosphate (PLP) and residue R62 plays an important role in catalyzing β- and γ-eliminations. Our study suggests that solvent ions such as NaCl disrupt electrostatic interactions between R62 and PLP, decreasing catalytic efficiency.

Mitrocomin from the jellyfish Mitrocoma cellularia with deleted C-terminal tyrosine reveals a higher bioluminescence activity compared to wild type photoprotein

Energy Technology Data Exchange (ETDEWEB)

Burakova, Ludmila P.; Natashin, Pavel V.; Markova, Svetlana V.; Eremeeva, Elena V.; Malikova, Natalia P.; Cheng, Chongyun; Liu, Zhi-Jie; Vysotski, Eugene S.

2016-09-01

The full-length cDNA genes encoding five new isoforms of Ca2 +-regulated photoprotein mitrocomin from a small tissue sample of the outer bell margin containing photocytes of only one specimen of the luminous jellyfish Mitrocoma cellularia were cloned, sequenced, and characterized after their expression in Escherichia coli and subsequent purification. The analysis of cDNA nucleotide sequences encoding mitrocomin isoforms allowed suggestion that two isoforms might be the products of two allelic genes differing in one amino acid residue (64R/Q) whereas other isotypes appear as a result of transcriptional mutations. In addition, the crystal structure of mitrocomin was determined at 1.30 Å resolution which expectedly revealed a high similarity with the structures of other hydromedusan photoproteins. Although mitrocomin isoforms reveal a high degree of identity of amino acid sequences, they vary in specific bioluminescence activities. At that, all isotypes displayed the identical bioluminescence spectra (473–474 nm with no shoulder at 400 nm). Fluorescence spectra of Ca2 +-discharged mitrocomins were almost identical to their light emission spectra similar to the case of Ca2 +-discharged aequorin, but different from Ca2 +-discharged obelins and clytin which fluorescence is red-shifted by 25–30 nm from bioluminescence spectra. The main distinction of mitrocomin from other hydromedusan photoproteins is an additional Tyr at the C-terminus. Using site-directed mutagenesis, we showed that this Tyr is not important for bioluminescence because its deletion even increases specific activity and efficiency of apo-mitrocomin conversion into active photoprotein, in contrast to C-terminal Pro of other photoproteins. Since genes in a population generally exist as different isoforms, it makes us anticipate the cloning of even more isoforms of mitrocomin and other hydromedusan photoproteins with different bioluminescence properties.

Structure-activity studies of RFamide peptides reveal subtype-selective activation of neuropeptide FF1 and FF2 receptors.

Science.gov (United States)

Findeisen, Maria; Rathmann, Daniel; Beck-Sickinger, Annette G

2011-06-06

Selectivity is a major issue in closely related multiligand/multireceptor systems. In this study we investigated the RFamide systems of hNPFF₁R and hNPFF₂R that bind the endogenous peptide hormones NPFF, NPAF, NPVF, and NPSF. By use of a systematic approach, we characterized the role of the C-terminal dipeptide with respect to agonistic properties using synthesized [Xaa 7]NPFF and [Xaa 8]NPFF analogues. We were able to identify only slight differences in potency upon changing the position of Arg 7, as all modifications resulted in identical behavior at the NPFF₁R and NPFF₂R. However, the C-terminal Phe 8 was able to be replaced by Trp or His with only a minor loss in potency at the NPFF₂R relative to the NPFF₁R. Analogues with shorter side chains, such as α-amino-4-guanidino butyric acid ([Agb 7]NPFF) or phenylglycine ([Phg 8]NPFF), decreased efficacy for the NPFF₁ R to 25-31 % of the maximal response, suggesting that these agonist-receptor complexes are more susceptible to structural modifications. In contrast, mutations to the conserved Asp 6.59 residue in the third extracellular loop of both receptors revealed a higher sensitivity toward the hNPFF₂R receptor than toward hNPFF₁R. These data provide new insight into the subtype-specific agonistic activation of the NPFF₁ and NPFF(2) receptors that are necessary for the development of selective agonists. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Teacher Knowledge for Active-Learning Instruction: Expert-Novice Comparison Reveals Differences.

Science.gov (United States)

Auerbach, A J; Higgins, M; Brickman, P; Andrews, T C

2018-01-01

Active-learning strategies can improve science, technology, engineering, and mathematics (STEM) undergraduates' abilities to learn fundamental concepts and skills. However, the results instructors achieve vary substantially. One explanation for this is that instructors commonly implement active learning differently than intended. An important factor affecting how instructors implement active learning is knowledge of teaching and learning. We aimed to discover knowledge that is important to effective active learning in large undergraduate courses. We developed a lesson-analysis instrument to elicit teacher knowledge, drawing on the theoretical construct of teacher noticing. We compared the knowledge used by expert ( n = 14) and novice ( n = 29) active-learning instructors as they analyzed lessons. Experts and novices differed in what they noticed, with experts more commonly considering how instructors hold students accountable, topic-specific student difficulties, whether the instructor elicited and responded to student thinking, and opportunities students had to generate their own ideas and work. Experts were also better able to support their lesson analyses with reasoning. This work provides foundational knowledge for the future design of preparation and support for instructors adopting active learning. Improving teacher knowledge will improve the implementation of active learning, which will be necessary to widely realize the potential benefits of active learning in undergraduate STEM. © 2018 A. J. Auerbach et al. CBE—Life Sciences Education © 2018 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Correlations between human mobility and social interaction reveal general activity patterns.

Science.gov (United States)

Mollgaard, Anders; Lehmann, Sune; Mathiesen, Joachim

2017-01-01

A day in the life of a person involves a broad range of activities which are common across many people. Going beyond diurnal cycles, a central question is: to what extent do individuals act according to patterns shared across an entire population? Here we investigate the interplay between different activity types, namely communication, motion, and physical proximity by analyzing data collected from smartphones distributed among 638 individuals. We explore two central questions: Which underlying principles govern the formation of the activity patterns? Are the patterns specific to each individual or shared across the entire population? We find that statistics of the entire population allows us to successfully predict 71% of the activity and 85% of the inactivity involved in communication, mobility, and physical proximity. Surprisingly, individual level statistics only result in marginally better predictions, indicating that a majority of activity patterns are shared across our sample population. Finally, we predict short-term activity patterns using a generalized linear model, which suggests that a simple linear description might be sufficient to explain a wide range of actions, whether they be of social or of physical character.

Synthesis and evaluation of 8,4'-dideshydroxy-leinamycin revealing new insights into the structure-activity relationship of the anticancer natural product leinamycin.

Science.gov (United States)

Liu, Tao; Ma, Ming; Ge, Hui-Ming; Yang, Chunying; Cleveland, John; Shen, Ben

2015-11-01

Leinamycin (LNM, 1) is a novel antitumor antibiotic produced by Streptomyces atroolivaceus S-140 and features an unusual 1,3-dioxo-1,2-dithiolane moiety that is spiro-fused to a thiazole-containing 18-membered lactam ring. The 1,3-dioxo-1,2-dithiolane moiety of LNM is essential for its antitumor activity via an episulfonium ion-mediated DNA alkylation upon reductive activation in the presence of cellular thiols. We recently isolated leinamycin E1 (LNM E1, 2) from an engineered strain S. atroolivaceus SB3033, which lacks the 1,3-dioxo-1,2-dithiolane moiety. Here we report the chemical synthesis of 8,4'-dideshydroxy-LNM (5) from 2 and determination of the cytotoxicity of 5 against selected cancer cell lines in comparison with 1; 5 exhibits comparable activity as 1 with the EC50 values between 8.21 and 275 nM. This work reveals new insight into the structure-activity relationship of LNM and highlights the synergy between metabolic pathway engineering and medicinal chemistry for natural product drug discovery. Copyright © 2015 Elsevier Ltd. All rights reserved.

Prognostic Value of Cortically Induced Motor Evoked Activity by TMS in Chronic Stroke: Caveats from a Revealing Single Clinical Case

LENUS (Irish Health Repository)

Amengual, Julià L

2012-06-08

AbstractBackgroundWe report the case of a chronic stroke patient (62 months after injury) showing total absence of motor activity evoked by transcranial magnetic stimulation (TMS) of spared regions of the left motor cortex, but near-to-complete recovery of motor abilities in the affected hand.Case presentationMultimodal investigations included detailed TMS based motor mapping, motor evoked potentials (MEP), and Cortical Silent period (CSP) as well as functional magnetic resonance imaging (fMRI) of motor activity, MRI based lesion analysis and Diffusion Tensor Imaging (DTI) Tractography of corticospinal tract (CST). Anatomical analysis revealed a left hemisphere subinsular lesion interrupting the descending left CST at the level of the internal capsule. The absence of MEPs after intense TMS pulses to the ipsilesional M1, and the reversible suppression of ongoing electromyographic (EMG) activity (indexed by CSP) demonstrate a weak modulation of subcortical systems by the ipsilesional left frontal cortex, but an inability to induce efficient descending volleys from those cortical locations to right hand and forearm muscles. Functional MRI recordings under grasping and finger tapping patterns involving the affected hand showed slight signs of subcortical recruitment, as compared to the unaffected hand and hemisphere, as well as the expected cortical activations.ConclusionsThe potential sources of motor voluntary activity for the affected hand in absence of MEPs are discussed. We conclude that multimodal analysis may contribute to a more accurate prognosis of stroke patients.

Prognostic value of cortically induced motor evoked activity by TMS in chronic stroke: Caveats from a revealing single clinical case

Directory of Open Access Journals (Sweden)

Amengual Julià L

2012-06-01

Full Text Available Abstract Background We report the case of a chronic stroke patient (62 months after injury showing total absence of motor activity evoked by transcranial magnetic stimulation (TMS of spared regions of the left motor cortex, but near-to-complete recovery of motor abilities in the affected hand. Case presentation Multimodal investigations included detailed TMS based motor mapping, motor evoked potentials (MEP, and Cortical Silent period (CSP as well as functional magnetic resonance imaging (fMRI of motor activity, MRI based lesion analysis and Diffusion Tensor Imaging (DTI Tractography of corticospinal tract (CST. Anatomical analysis revealed a left hemisphere subinsular lesion interrupting the descending left CST at the level of the internal capsule. The absence of MEPs after intense TMS pulses to the ipsilesional M1, and the reversible suppression of ongoing electromyographic (EMG activity (indexed by CSP demonstrate a weak modulation of subcortical systems by the ipsilesional left frontal cortex, but an inability to induce efficient descending volleys from those cortical locations to right hand and forearm muscles. Functional MRI recordings under grasping and finger tapping patterns involving the affected hand showed slight signs of subcortical recruitment, as compared to the unaffected hand and hemisphere, as well as the expected cortical activations. Conclusions The potential sources of motor voluntary activity for the affected hand in absence of MEPs are discussed. We conclude that multimodal analysis may contribute to a more accurate prognosis of stroke patients.

Revealing Rembrandt

Directory of Open Access Journals (Sweden)

Andrew J Parker

2014-04-01

Full Text Available The power and significance of artwork in shaping human cognition is self-evident. The starting point for our empirical investigations is the view that the task of neuroscience is to integrate itself with other forms of knowledge, rather than to seek to supplant them. In our recent work, we examined a particular aspect of the appreciation of artwork using present-day functional magnetic resonance imaging (fMRI. Our results emphasised the continuity between viewing artwork and other human cognitive activities. We also showed that appreciation of a particular aspect of artwork, namely authenticity, depends upon the co-ordinated activity between the brain regions involved in multiple decision making and those responsible for processing visual information. The findings about brain function probably have no specific consequences for understanding how people respond to the art of Rembrandt in comparison with their response to other artworks. However, the use of images of Rembrandt’s portraits, his most intimate and personal works, clearly had a significant impact upon our viewers, even though they have been spatially confined to the interior of an MRI scanner at the time of viewing. Neuroscientific studies of humans viewing artwork have the capacity to reveal the diversity of human cognitive responses that may be induced by external advice or context as people view artwork in a variety of frameworks and settings.

Activity patterns of free-ranging koalas (Phascolarctos cinereus revealed by accelerometry.

Directory of Open Access Journals (Sweden)

Michelle A Ryan

Full Text Available An understanding of koala activity patterns is important for measuring the behavioral response of this species to environmental change, but to date has been limited by the logistical challenges of traditional field methodologies. We addressed this knowledge gap by using tri-axial accelerometer data loggers attached to VHF radio collars to examine activity patterns of adult male and female koalas in a high-density population at Cape Otway, Victoria, Australia. Data were obtained from 27 adult koalas over two 7-d periods during the breeding season: 12 in the early-breeding season in November 2010, and 15 in the late-breeding season in January 2011. Multiple 15 minute observation blocks on each animal were used for validation of activity patterns determined from the accelerometer data loggers. Accelerometry was effective in distinguishing between inactive (sleeping, resting and active (grooming, feeding and moving behaviors. Koalas were more active during the early-breeding season with a higher index of movement (overall dynamic body acceleration [ODBA] for both males and females. Koalas showed a distinct temporal pattern of behavior, with most activity occurring from mid-afternoon to early morning. Accelerometry has potential for examining fine-scale behavior of a wide range of arboreal and terrestrial species.

Activity patterns of free-ranging koalas (Phascolarctos cinereus) revealed by accelerometry.

Science.gov (United States)

Ryan, Michelle A; Whisson, Desley A; Holland, Greg J; Arnould, John P Y

2013-01-01

An understanding of koala activity patterns is important for measuring the behavioral response of this species to environmental change, but to date has been limited by the logistical challenges of traditional field methodologies. We addressed this knowledge gap by using tri-axial accelerometer data loggers attached to VHF radio collars to examine activity patterns of adult male and female koalas in a high-density population at Cape Otway, Victoria, Australia. Data were obtained from 27 adult koalas over two 7-d periods during the breeding season: 12 in the early-breeding season in November 2010, and 15 in the late-breeding season in January 2011. Multiple 15 minute observation blocks on each animal were used for validation of activity patterns determined from the accelerometer data loggers. Accelerometry was effective in distinguishing between inactive (sleeping, resting) and active (grooming, feeding and moving) behaviors. Koalas were more active during the early-breeding season with a higher index of movement (overall dynamic body acceleration [ODBA]) for both males and females. Koalas showed a distinct temporal pattern of behavior, with most activity occurring from mid-afternoon to early morning. Accelerometry has potential for examining fine-scale behavior of a wide range of arboreal and terrestrial species.

Mutational analysis of an archaeal minichromosome maintenance protein exterior hairpin reveals critical residues for helicase activity and DNA binding

Directory of Open Access Journals (Sweden)

Brewster Aaron S

2010-08-01

Full Text Available Abstract Background The mini-chromosome maintenance protein (MCM complex is an essential replicative helicase for DNA replication in Archaea and Eukaryotes. While the eukaryotic complex consists of six homologous proteins (MCM2-7, the archaeon Sulfolobus solfataricus has only one MCM protein (ssoMCM, six subunits of which form a homohexamer. We have recently reported a 4.35Å crystal structure of the near full-length ssoMCM. The structure reveals a total of four β-hairpins per subunit, three of which are located within the main channel or side channels of the ssoMCM hexamer model generated based on the symmetry of the N-terminal Methanothermobacter thermautotrophicus (mtMCM structure. The fourth β-hairpin, however, is located on the exterior of the hexamer, near the exit of the putative side channels and next to the ATP binding pocket. Results In order to better understand this hairpin's role in DNA binding and helicase activity, we performed a detailed mutational and biochemical analysis of nine residues on this exterior β-hairpin (EXT-hp. We examined the activities of the mutants related to their helicase function, including hexamerization, ATPase, DNA binding and helicase activities. The assays showed that some of the residues on this EXT-hp play a role for DNA binding as well as for helicase activity. Conclusions These results implicate several current theories regarding helicase activity by this critical hexameric enzyme. As the data suggest that EXT-hp is involved in DNA binding, the results reported here imply that the EXT-hp located near the exterior exit of the side channels may play a role in contacting DNA substrate in a manner that affects DNA unwinding.

Spores of most common airborne fungi reveal no ice nucleation activity

Science.gov (United States)

Pummer, B. G.; Atanasova, L.; Bauer, H.; Bernardi, J.; Druzhinina, I. S.; Grothe, H.

2013-06-01

Fungal spores are ubiquitous biological aerosols, which are considered to show ice nucleation (IN) activity. In this study the respective IN activity was tested in oil emulsion in the immersion freezing mode. The focus was laid on species of economical, ecological or sanitary significance. For the first time, not only common moulds, but also edible mushrooms (Basidiomycota, Agaricomycetes) were investigated, as they contribute massively to the total amount of fungal spores in the atmosphere. Only Fusarium avenaceum showed freezing events at low subzero-temperatures, while the other investigated fungal spores showed no significant IN activity. Furthermore, we selected a set of fungal strains from different sites and exposed them to occasional freezing stress during cultivation. Although the total protein expression was altered by this treatment, it had no significant impact on the IN activity.

Correlations between human mobility and social interaction reveal general activity patterns

DEFF Research Database (Denmark)

Mollgaard, Anders; Jørgensen, Sune Lehmann; Mathiesen, Joachim

2017-01-01

activity types, namely communication, motion, and physical proximity by analyzing data collected from smartphones distributed among 638 individuals. We explore two central questions: Which underlying principles govern the formation of the activity patterns? Are the patterns specific to each individual...... or shared across the entire population? We find that statistics of the entire population allows us to successfully predict 71% of the activity and 85% of the inactivity involved in communication, mobility, and physical proximity. Surprisingly, individual level statistics only result in marginally better...... they be of social or of physical character....

Teacher Knowledge for Active-Learning Instruction: Expert-Novice Comparison Reveals Differences

Science.gov (United States)

Auerbach, A. J.; Higgins, M.; Brickman, P.; Andrews, T. C.

2018-01-01

Active-learning strategies "can" improve science, technology, engineering, and mathematics (STEM) undergraduates' abilities to learn fundamental concepts and skills. However, the results instructors achieve vary substantially. One explanation for this is that instructors commonly implement active learning differently than intended. An…

Functional MRI examination of empathy for pain in people with schizophrenia reveals abnormal activation related to cognitive perspective-taking but typical activation linked to affective sharing

Science.gov (United States)

Vistoli, Damien; Lavoie, Marie-Audrey; Sutliff, Stephanie; Jackson, Philip L.; Achim, Amélie M.

2017-01-01

Background Schizophrenia is associated with important disturbances in empathy that are related to everyday functioning. Empathy is classically defined as including affective (sharing others’ emotions) and cognitive (taking others’ cognitive perspectives) processes. In healthy individuals, studies on empathy for pain revealed specific brain systems associated with these sets of processes, notably the anterior middle cingulate (aMCC) and anterior insula (AI) for affective sharing and the bilateral temporoparietal junction (TPJ) for the cognitive processes, but the integrity of these systems in patients with schizophrenia remains uncertain. Methods Patients with schizophrenia and healthy controls performed a pain empathy task while undergoing fMRI scanning. Participants observed pictures of hands in either painful or nonpainful situations and rated the level of pain while imagining either themselves (self) or an unknown person (other) in these situations. Results We included 27 patients with schizophrenia and 21 healthy controls in our analyses. For the pain versus no pain contrast, patients showed overall typical activation patterns in the aMCC and AI, with only a small part of the aMCC showing reduced activation compared with controls. For the other versus self contrast, patients showed an abnormal modulation of activation in the TPJ bilaterally (extending to the posterior superior temporal sulcus, referred to as the TPJ/pSTS). Limitations The design included an unnecessary manipulation of the visual perspective that reduced the number of trials for analysis. The sample size may not account for the heterogeneity of schizophrenia. Conclusion People with schizophrenia showed relatively intact brain activation when observing others’ pain, but showed abnormalities when asked to take the cognitive perspectives of others. PMID:28556774

Transgenic Analysis of the Leishmania MAP Kinase MPK10 Reveals an Auto-inhibitory Mechanism Crucial for Stage-Regulated Activity and Parasite Viability

DEFF Research Database (Denmark)

Cayla, M.; Rachidi, N.; Leclercq, O.

2014-01-01

Protozoan pathogens of the genus Leishmania have evolved unique signaling mechanisms that can sense changes in the host environment and trigger adaptive stage differentiation essential for host cell infection. The signaling mechanisms underlying parasite development remain largely elusive even...... though Leishmania mitogen-activated protein kinases (MAPKs) have been linked previously to environmentally induced differentiation and virulence. Here, we unravel highly unusual regulatory mechanisms for Leishmania MAP kinase 10 (MPK10). Using a transgenic approach, we demonstrate that MPK10 is stage...... at position 395 that could be implicated in kinase regulation. Finally, we uncovered a feedback loop that limits MPK10 activity through dephosphorylation of the tyrosine residue of the TxY motif. Together our data reveal novel aspects of protein kinase regulation in Leishmania, and propose MPK10...

A novel low-temperature-active β-glucosidase from symbiotic Serratia sp. TN49 reveals four essential positions for substrate accommodation.

Science.gov (United States)

Zhou, Junpei; Zhang, Rui; Shi, Pengjun; Huang, Huoqing; Meng, Kun; Yuan, Tiezheng; Yang, Peilong; Yao, Bin

2011-10-01

A 2,373-bp full-length gene (bglA49) encoding a 790-residue polypeptide (BglA49) with a calculated mass of 87.8 kDa was cloned from Serratia sp. TN49, a symbiotic bacterium isolated from the gut of longhorned beetle (Batocera horsfieldi) larvae. The deduced amino acid sequence of BglA49 showed the highest identities of 80.1% with a conceptually translated protein from Pantoea sp. At-9b (EEW02556), 38.3% with the identified glycoside hydrolase (GH) family 3 β-glucosidase from Clostridium stercorarium NCBI 11754 (CAB08072), and sp. G5 (ABL09836) and Paenibacillus sp. C7 (AAX35883). The recombinant enzyme (r-BglA49) was expressed in Escherichia coli and displayed the typical characteristics of low-temperature-active enzymes, such as low temperature optimum (showing apparent optimal activity at 35°C), activity at low temperatures (retaining approximately 60% of its maximum activity at 20°C and approximately 25% at 10°C). Compared with the thermophilic GH 3 β-glucosidase, r-BglA49 had fewer hydrogen bonds and salt bridges and less proline residues. These features might relate to the increased structure flexibility and higher catalytic activity at low temperatures of r-BglA49. The molecular docking study of four GH 3 β-glucosidases revealed five conserved positions contributing to substrate accommodation, among which four positions of r-BglA49 (R192, Y228, D260, and E449) were identified to be essential based on site-directed mutagenesis analysis.

Structural Characterization of Maize SIRK1 Kinase Domain Reveals an Unusual Architecture of the Activation Segment

Directory of Open Access Journals (Sweden)

Bruno Aquino

2017-05-01

Full Text Available Kinases are primary regulators of plant metabolism and excellent targets for plant breeding. However, most kinases, including the abundant receptor-like kinases (RLK, have no assigned role. SIRK1 is a leucine-rich repeat receptor-like kinase (LRR-RLK, the largest family of RLK. In Arabidopsis thaliana, SIRK1 (AtSIRK1 is phosphorylated after sucrose is resupplied to sucrose-starved seedlings and it modulates the sugar response by phosphorylating several substrates. In maize, the ZmSIRK1 expression is altered in response to drought stress. In neither Arabidopsis nor in maize has the function of SIRK1 been completely elucidated. As a first step toward the biochemical characterization of ZmSIRK1, we obtained its recombinant kinase domain, demonstrated that it binds AMP-PNP, a non-hydrolysable ATP-analog, and solved the structure of ZmSIRK1- AMP-PNP co-crystal. The ZmSIRK1 crystal structure revealed a unique conformation for the activation segment. In an attempt to find inhibitors for ZmSIRK1, we screened a focused small molecule library and identified six compounds that stabilized ZmSIRK1 against thermal melt. ITC analysis confirmed that three of these compounds bound to ZmSIRK1 with low micromolar affinity. Solving the 3D structure of ZmSIRK1-AMP-PNP co-crystal provided information on the molecular mechanism of ZmSIRK1 activity. Furthermore, the identification of small molecules that bind this kinase can serve as initial backbone for development of new potent and selective ZmSIRK1 antagonists.

FRET biosensors reveal AKAP-mediated shaping of subcellular PKA activity and a novel mode of Ca(2+)/PKA crosstalk.

Science.gov (United States)

Schott, Micah B; Gonowolo, Faith; Maliske, Benjamin; Grove, Bryon

2016-04-01

Scaffold proteins play a critical role in cellular homeostasis by anchoring signaling enzymes in close proximity to downstream effectors. In addition to anchoring static enzyme complexes, some scaffold proteins also form dynamic signalosomes that can traffic to different subcellular compartments upon stimulation. Gravin (AKAP12), a multivalent scaffold, anchors PKA and other enzymes to the plasma membrane under basal conditions, but upon [Ca(2+)]i elevation, is rapidly redistributed to the cytosol. Because gravin redistribution also impacts PKA localization, we postulate that gravin acts as a calcium "switch" that modulates PKA-substrate interactions at the plasma membrane, thus facilitating a novel crosstalk mechanism between Ca(2+) and PKA-dependent pathways. To assess this, we measured the impact of gravin-V5/His expression on compartmentalized PKA activity using the FRET biosensor AKAR3 in cultured cells. Upon treatment with forskolin or isoproterenol, cells expressing gravin-V5/His showed elevated levels of plasma membrane PKA activity, but cytosolic PKA activity levels were reduced compared with control cells lacking gravin. This effect required both gravin interaction with PKA and localization at the plasma membrane. Pretreatment with calcium-elevating agents thapsigargin or ATP caused gravin redistribution away from the plasma membrane and prevented gravin from elevating PKA activity levels at the membrane. Importantly, this mode of Ca(2+)/PKA crosstalk was not observed in cells expressing a gravin mutant that resisted calcium-mediated redistribution from the cell periphery. These results reveal that gravin impacts subcellular PKA activity levels through the spatial targeting of PKA, and that calcium elevation modulates downstream β-adrenergic/PKA signaling through gravin redistribution, thus supporting the hypothesis that gravin mediates crosstalk between Ca(2+) and PKA-dependent signaling pathways. Based on these results, AKAP localization dynamics may

FRET biosensors reveal AKAP-mediated shaping of subcellular PKA activity and a novel mode of Ca2+/PKA crosstalk

Science.gov (United States)

Schott, Micah; Gonowolo, Faith; Maliske, Ben; Grove, Bryon

2016-01-01

Scaffold proteins play a critical role in cellular homeostasis by anchoring signaling enzymes in close proximity to downstream effectors. In addition to anchoring static enzyme complexes, some scaffold proteins also form dynamic signalosomes that can traffic to different subcellular compartments upon stimulation. Gravin (AKAP12), a multivalent scaffold, anchors PKA and other enzymes to the plasma membrane under basal conditions, but upon [Ca2+]i elevation, is rapidly redistributed to the cytosol. Because gravin redistribution also impacts PKA localization, we postulate that gravin acts as a calcium “switch” that modulates PKA-substrate interactions at the plasma membrane, thus facilitating a novel crosstalk mechanism between Ca2+ and PKA-dependent pathways. To assess this, we measured the impact of gravin-V5/His expression on compartmentalized PKA activity using the FRET biosensor AKAR3 in cultured cells. Upon treatment with forskolin or isoproterenol, cells expressing gravin-V5/His showed elevated levels of plasma membrane PKA activity, but cytosolic PKA activity levels were reduced compared with control cells lacking gravin. This effect required both gravin interaction with PKA and localization at the plasma membrane. Pretreatment with calcium-elevating agents thapsigargin or ATP caused gravin redistribution away from the plasma membrane and prevented gravin from elevating PKA activity levels at the membrane. Importantly, this mode of Ca2+/PKA crosstalk was not observed in cells expressing a gravin mutant that resists calcium-mediated redistribution from the cell periphery. These results reveal that gravin impacts subcellular PKA activity levels through the spatial targeting of PKA, and that calcium elevation modulates downstream β-adrenergic/PKA signaling through gravin redistribution, thus supporting the hypothesis that gravin mediates crosstalk between Ca2+ and PKA-dependent signaling pathways. Based on these results, AKAP localization dynamics may

Improvement and automatization of a proportional alpha-beta counting system - FAG

International Nuclear Information System (INIS)

German, U.; Levinson, S.; Pelled, O.; Shemesh, Y.; Assido, H.

1997-01-01

An alpha and beta counting system - FAG*, for planchette samples is operated at the Health Physics department's laboratory of the NRCN. The original operation mode of the system was based on manual tasks handled by the FHT1 100 electronics. An option for a basic computer keyboard operation was available too. A computer with an appropriate I/O card was connected to the system and a new operating program was developed which enables full automatic control of the various components. The program includes activity calculations and statistical checks as well as data management. A bar-code laser system for sample number reading was integrated into the Alpha-Beta automatic counting system. The sample identification by means of an attached bar-code label enables unmistakable and reliable attribution of results to the counted sample. authors)

Right and left amygdalae activation in patients with major depression receiving antidepressant treatment, as revealed by fMRI.

Science.gov (United States)

Chen, Yen-Ting; Huang, Min-Wei; Hung, I-Chung; Lane, Hsien-Yuan; Hou, Chun-Ju

2014-10-08

A differential contribution of the right and left amygdalae to affective information processing has been proposed. However, the direction of this lateralization has not been confirmed. In this study, we used a pre- and post-treatment (escitalopram) design to analyze the relative differences between neural activity in the right and left amygdalae during exposure to emotional stimuli in currently depressed patients. To the best of our knowledge, this study is to compare neural activity between the left and right amygdalae in people with depression. Our findings could lead to the development of parameters or biomarkers for depressive symptoms and treatment response. We used a pre-post-test design without a control group. Twenty currently depressed participants underwent an emotion processing task during fMRI. These participants were then treated with an antidepressant for 6 weeks. We used amygdala region-of-interest analysis to evaluate the hemodynamic response during exposure to colored emotional pictures. In total, thirteen of the 20 participants were placed into a separate group based on degree of response to antidepressants. The partial response group had an averaged HDRS score of 10.75 ± 2.25 and an averaged DBOLDLR signal of 189.18 ± 140.23 (m1 = 8), and the remitted group had an averaged HDRS score of 4.80 ± 1.64 and an averaged DBOLDLR signal of 421.26 ± 109.19 (m2 = 5). Each individual had lateralized amygdala activity, and the direction of asymmetry persisted following treatment. Amygdala responses to four types of emotional stimuli did not significantly change (p > 0.05) with treatment in either the right or the left amygdala. However, the difference in neural activity between the right and left amygdalae was greater after treatment, and the variation in neural activity was larger in the left amygdala. We found that the response between the right and left amygdala did not differ in terms of time series, although activity increased after pharmaceutical

Structural and biochemical characterization of phage λ FI protein (gpFI) reveals a novel mechanism of DNA packaging chaperone activity.

Science.gov (United States)

Popovic, Ana; Wu, Bin; Arrowsmith, Cheryl H; Edwards, Aled M; Davidson, Alan R; Maxwell, Karen L

2012-09-14

One of the final steps in the morphogenetic pathway of phage λ is the packaging of a single genome into a preformed empty head structure. In addition to the terminase enzyme, the packaging chaperone, FI protein (gpFI), is required for efficient DNA packaging. In this study, we demonstrate an interaction between gpFI and the major head protein, gpE. Amino acid substitutions in gpFI that reduced the strength of this interaction also decreased the biological activity of gpFI, implying that this head binding activity is essential for the function of gpFI. We also show that gpFI is a two-domain protein, and the C-terminal domain is responsible for the head binding activity. Using nuclear magnetic resonance spectroscopy, we determined the three-dimensional structure of the C-terminal domain and characterized the helical nature of the N-terminal domain. Through structural comparisons, we were able to identify two previously unannotated prophage-encoded proteins with tertiary structures similar to gpFI, although they lack significant pairwise sequence identity. Sequence analysis of these diverse homologues led us to identify related proteins in a variety of myo- and siphophages, revealing that gpFI function has a more highly conserved role in phage morphogenesis than was previously appreciated. Finally, we present a novel model for the mechanism of gpFI chaperone activity in the DNA packaging reaction of phage λ.

Vibrio lentus protects gnotobiotic sea bass (Dicentrarchus labrax L.) larvae against challenge with Vibrio harveyi.

Science.gov (United States)

Schaeck, M; Duchateau, L; Van den Broeck, W; Van Trappen, S; De Vos, P; Coulombet, C; Boon, N; Haesebrouck, F; Decostere, A

2016-03-15

Due to the mounting awareness of the risks associated with the use of antibiotics in aquaculture, treatment with probiotics has recently emerged as the preferred environmental-friendly prophylactic approach in marine larviculture. However, the presence of unknown and variable microbiota in fish larvae makes it impossible to disentangle the efficacy of treatment with probiotics. In this respect, the recent development of a germ-free culture model for European sea bass (Dicentrarchus labrax L.) larvae opened the door for more controlled studies on the use of probiotics. In the present study, 206 bacterial isolates, retrieved from sea bass larvae and adults, were screened in vitro for haemolytic activity, bile tolerance and antagonistic activity against six sea bass pathogens. Subsequently, the harmlessness and the protective effect of the putative probiotic candidates against the sea bass pathogen Vibrio harveyi were evaluated in vivo adopting the previously developed germ-free sea bass larval model. An equivalence trial clearly showed that no harmful effect on larval survival was elicited by all three selected probiotic candidates: Bacillus sp. LT3, Vibrio lentus and Vibrio proteolyticus. Survival of Vibrio harveyi challenged larvae treated with V. lentus was superior in comparison with the untreated challenged group, whereas this was not the case for the larvae supplemented with Bacillus sp. LT3 and V. proteolyticus. In this respect, our results unmistakably revealed the protective effect of V. lentus against vibriosis caused by V. harveyi in gnotobiotic sea bass larvae, rendering this study the first in its kind. Copyright © 2016. Published by Elsevier B.V.

Molecular Dynamics Simulations of Orai Reveal How the Third Transmembrane Segment Contributes to Hydration and Ca2+ Selectivity in Calcium Release-Activated Calcium Channels.

Science.gov (United States)

Alavizargar, Azadeh; Berti, Claudio; Ejtehadi, Mohammad Reza; Furini, Simone

2018-04-26

Calcium release-activated calcium (CRAC) channels open upon depletion of Ca 2+ from the endoplasmic reticulum, and when open, they are permeable to a selective flux of calcium ions. The atomic structure of Orai, the pore domain of CRAC channels, from Drosophila melanogaster has revealed many details about conduction and selectivity in this family of ion channels. However, it is still unclear how residues on the third transmembrane helix can affect the conduction properties of the channel. Here, molecular dynamics and Brownian dynamics simulations were employed to analyze how a conserved glutamate residue on the third transmembrane helix (E262) contributes to selectivity. The comparison between the wild-type and mutated channels revealed a severe impact of the mutation on the hydration pattern of the pore domain and on the dynamics of residues K270, and Brownian dynamics simulations proved that the altered configuration of residues K270 in the mutated channel impairs selectivity to Ca 2+ over Na + . The crevices of water molecules, revealed by molecular dynamics simulations, are perfectly located to contribute to the dynamics of the hydrophobic gate and the basic gate, suggesting a possible role in channel opening and in selectivity function.

Characterization of DNA polymerase X from Thermus thermophilus HB8 reveals the POLXc and PHP domains are both required for 3'-5' exonuclease activity.

Science.gov (United States)

Nakane, Shuhei; Nakagawa, Noriko; Kuramitsu, Seiki; Masui, Ryoji

2009-04-01

The X-family DNA polymerases (PolXs) comprise a highly conserved DNA polymerase family found in all kingdoms. Mammalian PolXs are known to be involved in several DNA-processing pathways including repair, but the cellular functions of bacterial PolXs are less known. Many bacterial PolXs have a polymerase and histidinol phosphatase (PHP) domain at their C-termini in addition to a PolX core (POLXc) domain, and possess 3'-5' exonuclease activity. Although both domains are highly conserved in bacteria, their molecular functions, especially for a PHP domain, are unknown. We found Thermus thermophilus HB8 PolX (ttPolX) has Mg(2+)/Mn(2+)-dependent DNA/RNA polymerase, Mn(2+)-dependent 3'-5' exonuclease and DNA-binding activities. We identified the domains of ttPolX by limited proteolysis and characterized their biochemical activities. The POLXc domain was responsible for the polymerase and DNA-binding activities but exonuclease activity was not detected for either domain. However, the POLXc and PHP domains interacted with each other and a mixture of the two domains had Mn(2+)-dependent 3'-5' exonuclease activity. Moreover, site-directed mutagenesis revealed catalytically important residues in the PHP domain for the 3'-5' exonuclease activity. Our findings provide a molecular insight into the functional domain organization of bacterial PolXs, especially the requirement of the PHP domain for 3'-5' exonuclease activity.

Studies on lactoferricin-derived Escherichia coli membrane-active peptides reveal differences in the mechanism of N-acylated versus nonacylated peptides.

Science.gov (United States)

Zweytick, Dagmar; Deutsch, Günter; Andrä, Jörg; Blondelle, Sylvie E; Vollmer, Ekkehard; Jerala, Roman; Lohner, Karl

2011-06-17

To improve the low antimicrobial activity of LF11, an 11-mer peptide derived from human lactoferricin, mutant sequences were designed based on the defined structure of LF11 in the lipidic environment. Thus, deletion of noncharged polar residues and strengthening of the hydrophobic N-terminal part upon adding a bulky hydrophobic amino acid or N-acylation resulted in enhanced antimicrobial activity against Escherichia coli, which correlated with the peptides' degree of perturbation of bacterial membrane mimics. Nonacylated and N-acylated peptides exhibited different effects at a molecular level. Nonacylated peptides induced segregation of peptide-enriched and peptide-poor lipid domains in negatively charged bilayers, although N-acylated peptides formed small heterogeneous domains resulting in a higher degree of packing defects. Additionally, only N-acylated peptides perturbed the lateral packing of neutral lipids and exhibited increased permeability of E. coli lipid vesicles. The latter did not correlate with the extent of improvement of the antimicrobial activity, which could be explained by the fact that elevated binding of N-acylated peptides to lipopolysaccharides of the outer membrane of gram-negative bacteria seems to counteract the elevated membrane permeabilization, reflected in the respective minimal inhibitory concentration for E. coli. The antimicrobial activity of the peptides correlated with an increase of membrane curvature stress and hence bilayer instability. Transmission electron microscopy revealed that only the N-acylated peptides induced tubular protrusions from the outer membrane, whereas all peptides caused detachment of the outer and inner membrane of E. coli bacteria. Viability tests demonstrated that these bacteria were dead before onset of visible cell lysis.

Studies on Lactoferricin-derived Escherichia coli Membrane-active Peptides Reveal Differences in the Mechanism of N-Acylated Versus Nonacylated Peptides*

Science.gov (United States)

Zweytick, Dagmar; Deutsch, Günter; Andrä, Jörg; Blondelle, Sylvie E.; Vollmer, Ekkehard; Jerala, Roman; Lohner, Karl

2011-01-01

To improve the low antimicrobial activity of LF11, an 11-mer peptide derived from human lactoferricin, mutant sequences were designed based on the defined structure of LF11 in the lipidic environment. Thus, deletion of noncharged polar residues and strengthening of the hydrophobic N-terminal part upon adding a bulky hydrophobic amino acid or N-acylation resulted in enhanced antimicrobial activity against Escherichia coli, which correlated with the peptides' degree of perturbation of bacterial membrane mimics. Nonacylated and N-acylated peptides exhibited different effects at a molecular level. Nonacylated peptides induced segregation of peptide-enriched and peptide-poor lipid domains in negatively charged bilayers, although N-acylated peptides formed small heterogeneous domains resulting in a higher degree of packing defects. Additionally, only N-acylated peptides perturbed the lateral packing of neutral lipids and exhibited increased permeability of E. coli lipid vesicles. The latter did not correlate with the extent of improvement of the antimicrobial activity, which could be explained by the fact that elevated binding of N-acylated peptides to lipopolysaccharides of the outer membrane of Gram-negative bacteria seems to counteract the elevated membrane permeabilization, reflected in the respective minimal inhibitory concentration for E. coli. The antimicrobial activity of the peptides correlated with an increase of membrane curvature stress and hence bilayer instability. Transmission electron microscopy revealed that only the N-acylated peptides induced tubular protrusions from the outer membrane, whereas all peptides caused detachment of the outer and inner membrane of E. coli bacteria. Viability tests demonstrated that these bacteria were dead before onset of visible cell lysis. PMID:21515687

Shared memories reveal shared structure in neural activity across individuals

Science.gov (United States)

Chen, J.; Leong, Y.C.; Honey, C.J.; Yong, C.H.; Norman, K.A.; Hasson, U.

2016-01-01

Our lives revolve around sharing experiences and memories with others. When different people recount the same events, how similar are their underlying neural representations? Participants viewed a fifty-minute movie, then verbally described the events during functional MRI, producing unguided detailed descriptions lasting up to forty minutes. As each person spoke, event-specific spatial patterns were reinstated in default-network, medial-temporal, and high-level visual areas. Individual event patterns were both highly discriminable from one another and similar between people, suggesting consistent spatial organization. In many high-order areas, patterns were more similar between people recalling the same event than between recall and perception, indicating systematic reshaping of percept into memory. These results reveal the existence of a common spatial organization for memories in high-level cortical areas, where encoded information is largely abstracted beyond sensory constraints; and that neural patterns during perception are altered systematically across people into shared memory representations for real-life events. PMID:27918531

Reconstituted NALP1 inflammasome reveals two-step mechanism of caspase-1 activation.

Science.gov (United States)

Faustin, Benjamin; Lartigue, Lydia; Bruey, Jean-Marie; Luciano, Frederic; Sergienko, Eduard; Bailly-Maitre, Beatrice; Volkmann, Niels; Hanein, Dorit; Rouiller, Isabelle; Reed, John C

2007-03-09

Interleukin (IL)-1beta maturation is accomplished by caspase-1-mediated proteolysis, an essential element of innate immunity. NLRs constitute a recently recognized family of caspase-1-activating proteins, which contain a nucleotide-binding oligomerization domain and leucine-rich repeat (LRR) domains and which assemble into multiprotein complexes to create caspase-1-activating platforms called "inflammasomes." Using purified recombinant proteins, we have reconstituted the NALP1 inflammasome and have characterized the requirements for inflammasome assembly and caspase-1 activation. Oligomerization of NALP1 and activation of caspase-1 occur via a two-step mechanism, requiring microbial product, muramyl-dipeptide, a component of peptidoglycan, followed by ribonucleoside triphosphates. Caspase-1 activation by NALP1 does not require but is enhanced by adaptor protein ASC. The findings provide the biochemical basis for understanding how inflammasome assembly and function are regulated, and shed light on NALP1 as a direct sensor of bacterial components in host defense against pathogens.

Habituation in non-neural organisms: evidence from slime moulds

OpenAIRE

Boisseau, Romain P.; Vogel, David; Dussutour, Audrey

2016-01-01

Learning, defined as a change in behaviour evoked by experience, has hitherto been investigated almost exclusively in multicellular neural organisms. Evidence for learning in non-neural multicellular organisms is scant, and only a few unequivocal reports of learning have been described in single-celled organisms. Here we demonstrate habituation, an unmistakable form of learning, in the non-neural organism Physarum polycephalum. In our experiment, using chemotaxis as the behavioural output and...

Activity flow over resting-state networks shapes cognitive task activations.

Science.gov (United States)

Cole, Michael W; Ito, Takuya; Bassett, Danielle S; Schultz, Douglas H

2016-12-01

Resting-state functional connectivity (FC) has helped reveal the intrinsic network organization of the human brain, yet its relevance to cognitive task activations has been unclear. Uncertainty remains despite evidence that resting-state FC patterns are highly similar to cognitive task activation patterns. Identifying the distributed processes that shape localized cognitive task activations may help reveal why resting-state FC is so strongly related to cognitive task activations. We found that estimating task-evoked activity flow (the spread of activation amplitudes) over resting-state FC networks allowed prediction of cognitive task activations in a large-scale neural network model. Applying this insight to empirical functional MRI data, we found that cognitive task activations can be predicted in held-out brain regions (and held-out individuals) via estimated activity flow over resting-state FC networks. This suggests that task-evoked activity flow over intrinsic networks is a large-scale mechanism explaining the relevance of resting-state FC to cognitive task activations.

Receptor activity-independent recruitment of βarrestin2 reveals specific signalling modes

Science.gov (United States)

Terrillon, Sonia; Bouvier, Michel

2004-01-01

The roles of βarrestins in regulating G protein coupling and receptor endocytosis following agonist stimulation of G protein-coupled receptors are well characterised. However, their ability to act on their own as direct modulators or activators of signalling remains poorly characterised. Here, βarrestin2 intrinsic signalling properties were assessed by forcing the recruitment of this accessory protein to vasopressin V1a or V2 receptors independently of agonist-promoted activation of the receptors. Such induction of a stable interaction with βarrestin2 initiated receptor endocytosis leading to intracellular accumulation of the βarrestin/receptor complexes. Interestingly, βarrestin2 association to a single receptor protomer was sufficient to elicit receptor dimer internalisation. In addition to recapitulating βarrestin2 classical actions on receptor trafficking, the receptor activity-independent recruitment of βarrestin2 activated the extracellular signal-regulated kinases. In the latter case, recruitment to the receptor itself was not required since kinase activation could be mediated by βarrestin2 translocation to the plasma membrane in the absence of any interacting receptor. These data demonstrate that βarrestin2 can act as a ‘bonafide' signalling molecule even in the absence of activated receptor. PMID:15385966

Culture-Independent Analyses Reveal Novel Anaerolineaceae as Abundant Primary Fermenters in Anaerobic Digesters Treating Waste Activated Sludge

Directory of Open Access Journals (Sweden)

Simon J. McIlroy

2017-06-01

Full Text Available Anaerobic digestion for biogas production is reliant on the tightly coupled synergistic activities of complex microbial consortia. Members of the uncultured A6 phylotype, within the phylum Chloroflexi, are among the most abundant genus-level-taxa of mesophilic anaerobic digester systems treating primary and surplus sludge from wastewater treatment plants, yet are known only by their 16S rRNA gene sequence. This study applied metagenomics to obtain a complete circular genome (2.57 Mbp from a representative of the A6 taxon. Preliminary annotation of the genome indicates these organisms to be anaerobic chemoorganoheterotrophs with a fermentative metabolism. Given their observed abundance, they are likely important primary fermenters in digester systems. Application of fluorescence in situ hybridisation probes designed in this study revealed their morphology to be short filaments present within the flocs. The A6 were sometimes co-located with the filamentous Archaea Methanosaeta spp. suggesting potential undetermined synergistic relationships. Based on its genome sequence and morphology we propose the species name Brevefilum fermentans gen. nov. sp. nov.

Transcriptomic analysis of tail regeneration in the lizard Anolis carolinensis reveals activation of conserved vertebrate developmental and repair mechanisms.

Directory of Open Access Journals (Sweden)

Elizabeth D Hutchins

Full Text Available Lizards, which are amniote vertebrates like humans, are able to lose and regenerate a functional tail. Understanding the molecular basis of this process would advance regenerative approaches in amniotes, including humans. We have carried out the first transcriptomic analysis of tail regeneration in a lizard, the green anole Anolis carolinensis, which revealed 326 differentially expressed genes activating multiple developmental and repair mechanisms. Specifically, genes involved in wound response, hormonal regulation, musculoskeletal development, and the Wnt and MAPK/FGF pathways were differentially expressed along the regenerating tail axis. Furthermore, we identified 2 microRNA precursor families, 22 unclassified non-coding RNAs, and 3 novel protein-coding genes significantly enriched in the regenerating tail. However, high levels of progenitor/stem cell markers were not observed in any region of the regenerating tail. Furthermore, we observed multiple tissue-type specific clusters of proliferating cells along the regenerating tail, not localized to the tail tip. These findings predict a different mechanism of regeneration in the lizard than the blastema model described in the salamander and the zebrafish, which are anamniote vertebrates. Thus, lizard tail regrowth involves the activation of conserved developmental and wound response pathways, which are potential targets for regenerative medical therapies.

KMOS"3"D Reveals Low-level Star Formation Activity in Massive Quiescent Galaxies at 0.7 < z < 2.7

International Nuclear Information System (INIS)

Belli, Sirio; Genzel, Reinhard; Förster Schreiber, Natascha M.; Wisnioski, Emily; Wilman, David J.; Mendel, J. Trevor; Beifiori, Alessandra; Bender, Ralf; Burkert, Andreas; Chan, Jeffrey; Davies, Rebecca L.; Davies, Ric; Fabricius, Maximilian; Fossati, Matteo; Galametz, Audrey; Lang, Philipp; Lutz, Dieter; Wuyts, Stijn; Brammer, Gabriel B.; Momcheva, Ivelina G.

2017-01-01

We explore the H α emission in the massive quiescent galaxies observed by the KMOS"3"D survey at 0.7 < z < 2.7. The H α line is robustly detected in 20 out of 120 UVJ -selected quiescent galaxies, and we classify the emission mechanism using the H α line width and the [N ii]/H α line ratio. We find that AGNs are likely to be responsible for the line emission in more than half of the cases. We also find robust evidence for star formation activity in nine quiescent galaxies, which we explore in detail. The H α kinematics reveal rotating disks in five of the nine galaxies. The dust-corrected H α star formation rates are low (0.2–7 M _⊙ yr"−"1), and place these systems significantly below the main sequence. The 24 μ m-based, infrared luminosities, instead, overestimate the star formation rates. These galaxies present a lower gas-phase metallicity compared to star-forming objects with similar stellar mass, and many of them have close companions. We therefore conclude that the low-level star formation activity in these nine quiescent galaxies is likely to be fueled by inflowing gas or minor mergers, and could be a sign of rejuvenation events.

Quantitative ligand and receptor binding studies reveal the mechanism of interleukin-36 (IL-36) pathway activation.

Science.gov (United States)

Zhou, Li; Todorovic, Viktor; Kakavas, Steve; Sielaff, Bernhard; Medina, Limary; Wang, Leyu; Sadhukhan, Ramkrishna; Stockmann, Henning; Richardson, Paul L; DiGiammarino, Enrico; Sun, Chaohong; Scott, Victoria

2018-01-12

IL-36 cytokines signal through the IL-36 receptor (IL-36R) and a shared subunit, IL-1RAcP (IL-1 receptor accessory protein). The activation mechanism for the IL-36 pathway is proposed to be similar to that of IL-1 in that an IL-36R agonist (IL-36α, IL-36β, or IL-36γ) forms a binary complex with IL-36R, which then recruits IL-1RAcP. Recent studies have shown that IL-36R interacts with IL-1RAcP even in the absence of an agonist. To elucidate the IL-36 activation mechanism, we considered all possible binding events for IL-36 ligands/receptors and examined these events in direct binding assays. Our results indicated that the agonists bind the IL-36R extracellular domain with micromolar affinity but do not detectably bind IL-1RAcP. Using surface plasmon resonance (SPR), we found that IL-1RAcP also does not bind IL-36R when no agonist is present. In the presence of IL-36α, however, IL-1RAcP bound IL-36R strongly. These results suggested that the main pathway to the IL-36R·IL-36α·IL-1RAcP ternary complex is through the IL-36R·IL-36α binary complex, which recruits IL-1RAcP. We could not measure the binding affinity of IL-36R to IL-1RAcP directly, so we engineered a fragment crystallizable-linked construct to induce IL-36R·IL-1RAcP heterodimerization and predicted the binding affinity during a complete thermodynamic cycle to be 74 μm The SPR analysis also indicated that the IL-36R antagonist IL-36Ra binds IL-36R with higher affinity and a much slower off rate than the IL-36R agonists, shedding light on IL-36 pathway inhibition. Our results reveal the landscape of IL-36 ligand and receptor interactions, improving our understanding of IL-36 pathway activation and inhibition. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Neural activity reveals perceptual grouping in working memory.

Science.gov (United States)

Rabbitt, Laura R; Roberts, Daniel M; McDonald, Craig G; Peterson, Matthew S

2017-03-01

There is extensive evidence that the contralateral delay activity (CDA), a scalp recorded event-related brain potential, provides a reliable index of the number of objects held in visual working memory. Here we present evidence that the CDA not only indexes visual object working memory, but also the number of locations held in spatial working memory. In addition, we demonstrate that the CDA can be predictably modulated by the type of encoding strategy employed. When individual locations were held in working memory, the pattern of CDA modulation mimicked previous findings for visual object working memory. Specifically, CDA amplitude increased monotonically until working memory capacity was reached. However, when participants were instructed to group individual locations to form a constellation, the CDA was prolonged and reached an asymptote at two locations. This result provides neural evidence for the formation of a unitary representation of multiple spatial locations. Published by Elsevier B.V.

Crystal Structure of Ripk4 Reveals Dimerization-Dependent Kinase Activity.

Science.gov (United States)

Huang, Christine S; Oberbeck, Nina; Hsiao, Yi-Chun; Liu, Peter; Johnson, Adam R; Dixit, Vishva M; Hymowitz, Sarah G

2018-05-01

Receptor-interacting protein kinase 4 (RIPK4) is a highly conserved regulator of epidermal differentiation. Members of the RIPK family possess a common kinase domain as well as unique accessory domains that likely dictate subcellular localization and substrate preferences. Mutations in human RIPK4 manifest as Bartsocas-Papas syndrome (BPS), a genetic disorder characterized by severe craniofacial and limb abnormalities. We describe the structure of the murine Ripk4 (MmRipk4) kinase domain, in ATP- and inhibitor-bound forms. The crystallographic dimer of MmRipk4 is similar to those of RIPK2 and BRAF, and we show that the intact dimeric entity is required for MmRipk4 catalytic activity through a series of engineered mutations and cell-based assays. We also assess the impact of BPS mutations on protein structure and activity to elucidate the molecular origins of the disease. Copyright © 2018 Elsevier Ltd. All rights reserved.

Functional imaging reveals movement preparatory activity in the vegetative state

Directory of Open Access Journals (Sweden)

Tristan A Bekinschtein

2011-01-01

Full Text Available The Vegetative State (VS is characterized by the absence of awareness of self or the environment and preserved autonomic functions. The diagnosis relies critically on the lack of consistent signs of purposeful behavior in response to external stimulation. Yet, given that patients with disorders of consciousness often exhibit fragmented movement patterns, voluntary actions may go unnoticed. Here we designed a simple motor paradigm that could potentially detect residual conscious awareness in VS patients with mild to severe brain damage by examining the neural correlates of motor preparation in response to verbal commands. Twenty-four patients who met the diagnostic criteria for VS were recruited for this study. Eleven of these patients showing preserved auditory evoked potentials underwent functional magnetic resonance imaging (fMRI to test for basic speech processing. Five of these patients, who showed word related activity, were included in a second fMRI study aimed at detecting functional changes in premotor cortex elicited by specific verbal instructions to move either their left or their right hand. Despite the lack of overt muscle activity, two patients out of five activated the dorsal premotor cortex contralateral to the instructed hand, consistent with movement preparation. Given that movement preparation in response to a motor command is a sign of purposeful behavior, our results are consistent with residual conscious awareness in these patients. We believe that the identification of positive results with fMRI using this simple task, may complement the clinical assessment by helping attain a more precise diagnosis in patients with disorders of consciousness.

Activities on Facebook reveal the depressive state of users.

Science.gov (United States)

Park, Sungkyu; Lee, Sang Won; Kwak, Jinah; Cha, Meeyoung; Jeong, Bumseok

2013-10-01

As online social media have become prominent, much effort has been spent on identifying users with depressive symptoms in order to aim at early diagnosis, treatment, and even prevention by using various online social media. In this paper, we focused on Facebook to discern any correlations between the platform's features and users' depressive symptoms. This work may be helpful in trying to reach and detect large numbers of depressed individuals more easily. Our goal was to develop a Web application and identify depressive symptom-related features from users of Facebook, a popular social networking platform. 55 Facebook users (male=40, female=15, mean age 24.43, SD 3.90) were recruited through advertisement fliers distributed to students in a large university in Korea. Using EmotionDiary, the Facebook application we developed, we evaluated depressive symptoms using the Center for Epidemiological Studies-Depression (CES-D) scale. We also provided tips and facts about depression to participants and measured their responses using EmotionDiary. To identify the Facebook features related to depression, correlation analyses were performed between CES-D and participants' responses to tips and facts or Facebook social features. Last, we interviewed depressed participants (CES-D≥25) to assess their depressive symptoms by a psychiatrist. Facebook activities had predictive power in distinguishing depressed and nondepressed individuals. Participants' response to tips and facts, which can be explained by the number of app tips viewed and app points, had a positive correlation (P=.04 for both cases), whereas the number of friends and location tags had a negative correlation with the CES-D scale (P=.08 and P=.045 respectively). Furthermore, in finding group differences in Facebook social activities, app tips viewed and app points resulted in significant differences (P=.01 and P=.03 respectively) between probably depressed and nondepressed individuals. Our results using Emotion

Genetically encoded proton sensors reveal activity-dependent pH changes in neurons

Directory of Open Access Journals (Sweden)

Joseph Valentino Raimondo

2012-05-01

Full Text Available The regulation of hydrogen ion concentration (pH is fundamental to cell viability, metabolism and enzymatic function. Within the nervous system, the control of pH is also involved in diverse and dynamic processes including development, synaptic transmission and the control of network excitability. As pH affects neuronal activity, and can also itself be altered by neuronal activity, the existence of tools to accurately measure hydrogen ion fluctuations is important for understanding the role pH plays under physiological and pathological conditions. Outside of their use as a marker of synaptic release, genetically encoded pH sensors have not been utilised to study hydrogen ion fluxes associated with network activity. By combining whole-cell patch clamp with simultaneous two-photon or confocal imaging, we quantified the amplitude and time course of neuronal, intracellular, acidic transients evoked by epileptiform activity in two separate in vitro models of temporal lobe epilepsy. In doing so, we demonstrate the suitability of three genetically encoded pH sensors: deGFP4, E2GFP and Cl-sensor for investigating activity-dependent pH changes at the level of single neurons.

Genetically encoded proton sensors reveal activity-dependent pH changes in neurons.

Science.gov (United States)

Raimondo, Joseph V; Irkle, Agnese; Wefelmeyer, Winnie; Newey, Sarah E; Akerman, Colin J

2012-01-01

The regulation of hydrogen ion concentration (pH) is fundamental to cell viability, metabolism, and enzymatic function. Within the nervous system, the control of pH is also involved in diverse and dynamic processes including development, synaptic transmission, and the control of network excitability. As pH affects neuronal activity, and can also itself be altered by neuronal activity, the existence of tools to accurately measure hydrogen ion fluctuations is important for understanding the role pH plays under physiological and pathological conditions. Outside of their use as a marker of synaptic release, genetically encoded pH sensors have not been utilized to study hydrogen ion fluxes associated with network activity. By combining whole-cell patch clamp with simultaneous two-photon or confocal imaging, we quantified the amplitude and time course of neuronal, intracellular, acidic transients evoked by epileptiform activity in two separate in vitro models of temporal lobe epilepsy. In doing so, we demonstrate the suitability of three genetically encoded pH sensors: deGFP4, E(2)GFP, and Cl-sensor for investigating activity-dependent pH changes at the level of single neurons.

Neural correlates reveal sub-lexical orthography and phonology during reading aloud: A review

Directory of Open Access Journals (Sweden)

Kalinka eTimmer

2014-08-01

Full Text Available The sub-lexical conversion of graphemes-to-phonemes (GPC during reading has been investigated extensively with behavioral measures, as well as event-related potentials (ERPs. Most research utilizes silent reading (e.g., lexical decision task for which phonological activation is not a necessity. However, recent research employed reading aloud to capture sub-lexical GPC. The masked priming paradigm avoids strategic processing and is therefore well suitable for capturing sub-lexical processing instead of lexical effects. By employing ERPs, the on-line time course of sub-lexical GPC can be observed before the overt response. ERPs have revealed that besides phonological activation, as revealed by behavioral studies, there is also early orthographic activation. This review describes studies in one’s native language, in one’s second language, and in a cross-language situation. We discuss the implications the ERP results have on different (computational models. First, the ERP results show that computational models should assume an early locus of the grapheme-to-phoneme-conversion (GPC. Second, cross-language studies reveal that the phonological representations from both languages of a bilingual become activated automatically and the phonology belonging to the context is selected rapidly. Therefore, it is important to extend the scope of computational models of reading (aloud to multiple lexicons.

Diverse Brain Myeloid Expression Profiles Reveal Distinct Microglial Activation States and Aspects of Alzheimer’s Disease Not Evident in Mouse Models

Directory of Open Access Journals (Sweden)

Brad A. Friedman

2018-01-01

Full Text Available Microglia, the CNS-resident immune cells, play important roles in disease, but the spectrum of their possible activation states is not well understood. We derived co-regulated gene modules from transcriptional profiles of CNS myeloid cells of diverse mouse models, including new tauopathy model datasets. Using these modules to interpret single-cell data from an Alzheimer’s disease (AD model, we identified microglial subsets—distinct from previously reported “disease-associated microglia”—expressing interferon-related or proliferation modules. We then analyzed whole-tissue RNA profiles from human neurodegenerative diseases, including a new AD dataset. Correcting for altered cellular composition of AD tissue, we observed elevated expression of the neurodegeneration-related modules, but also modules not implicated using expression profiles from mouse models alone. We provide a searchable, interactive database for exploring gene expression in all these datasets (http://research-pub.gene.com/BrainMyeloidLandscape. Understanding the dimensions of CNS myeloid cell activation in human disease may reveal opportunities for therapeutic intervention.

Different patterns of auditory cortex activation revealed by functional magnetic resonance imaging

International Nuclear Information System (INIS)

Formisano, E.; Pepino, A.; Bracale, M.; Di Salle, F.; Lanfermann, H.; Zanella, F.E.

1998-01-01

In the last few years, functional Magnetic Resonance Imaging (fMRI) has been widely accepted as an effective tool for mapping brain activities in both the sensorimotor and the cognitive field. The present work aims to assess the possibility of using fMRI methods to study the cortical response to different acoustic stimuli. Furthermore, we refer to recent data collected at Frankfurt University on the cortical pattern of auditory hallucinations. Healthy subjects showed broad bilateral activation, mostly located in the transverse gyrus of Heschl. The analysis of the cortical activation induced by different stimuli has pointed out a remarkable difference in the spatial and temporal features of the auditory cortex response to pulsed tones and pure tones. The activated areas during episodes of auditory hallucinations match the location of primary auditory cortex as defined in control measurements with the same patients and in the experiments on healthy subjects. (authors)

Reveal the response of enzyme activities to heavy metals through in situ zymography.

Science.gov (United States)

Duan, Chengjiao; Fang, Linchuan; Yang, Congli; Chen, Weibin; Cui, Yongxing; Li, Shiqing

2018-07-30

Enzymes in the soil are vital for assessing heavy metal soil pollution. Although the presence of heavy metals is thought to change the soil enzyme system, the distribution of enzyme activities in heavy metal polluted-soil is still unknown. For the first time, using soil zymography, we analyzed the distribution of enzyme activities of alfalfa rhizosphere and soil surface in the metal-contaminated soil. The results showed that the growth of alfalfa was significantly inhibited, and an impact that was most pronounced in seedling biomass and chlorophyll content. Catalase activity (CAT) in alfalfa decreased with increasing heavy metal concentrations, while malondialdehyde (MDA) content continually increased. The distribution of enzyme activities showed that both phosphatase and β-glucosidase activities were associated with the roots and were rarely distributed throughout the soil. In addition, the total hotspot areas of enzyme activities were the highest in extremely heavy pollution soil. The hotspot areas of phosphatase were 3.4%, 1.5% and 7.1% under none, moderate and extremely heavy pollution treatment, respectively, but increased from 0.1% to 0.9% for β-glucosidase with the increasing pollution levels. Compared with the traditional method of enzyme activities, zymography can directly and accurately reflect the distribution and extent of enzyme activity in heavy metals polluted soil. The results provide an efficient research method for exploring the interaction between enzyme activities and plant rhizosphere. Copyright © 2018 Elsevier Inc. All rights reserved.

Comparative proteomic analyses reveal that FlbA down-regulates gliT expression and SOD activity in Aspergillus fumigatus.

Science.gov (United States)

Shin, Kwang-Soo; Park, Hee-Soo; Kim, Young-Hwan; Yu, Jae-Hyuk

2013-07-11

FlbA is a regulator of G-protein signaling protein that plays a central role in attenuating heterotrimeric G-protein mediated vegetative growth signaling in Aspergillus. The deletion of flbA (∆flbA) in the opportunistic human pathogen Aspergillus fumigatus results in accelerated cell death and autolysis in submerged culture. To further investigate the effects of ∆flbA on intracellular protein levels we carried out 2-D proteome analyses of 2-day old submerged cultures of ∆flbA and wild type (WT) strains and observed 160 differentially expressed proteins. Via nano-LC-ESI-MS/MS analyses, we revealed the identity of 10 and 2 proteins exhibiting high and low level accumulation, respectively, in ∆flbA strain. Notably, the GliT protein is accumulated at about 1800-fold higher levels in ∆flbA than WT. Moreover, GliT is secreted at high levels from ∆flbA strain, whereas Sod1 (superoxide dismutase) is secreted at a higher level in WT. Northern blot analyses reveal that ∆flbA results in elevated accumulation of gliT mRNA. Consequently, ∆flbA strain exhibits enhanced tolerance to gliotoxin toxicity. Finally, ∆flbA strain displayed enhanced SOD activity and elevated resistance to menadione and paraquat. In summary, FlbA-mediated signaling control negatively affects cellular responses associated with detoxification of reactive oxygen species and of exogenous gliotoxin in A. fumigatus. Regulator of G protein Signaling (RGS) proteins play crucial roles in fundamental biological processes in filamentous fungi. FlbA is the first studied filamentous fungal RGS protein, yet much remains to be understood about its roles in the opportunistic human pathogen Aspergillus fumigatus. In the present study, we examined the effects of the deletion of flbA using comprehensive analyses of the intra- and extracellular proteomes of A. fumigatus wild type and the flbA deletion mutant. Via MS analyses, we identified 10 proteins exhibiting high level accumulation in the flbA deletion

Seasonal succession in zooplankton feeding traits reveals trophic trait coupling

DEFF Research Database (Denmark)

Kenitz, Kasia; Visser, Andre; Mariani, Patrizio

2017-01-01

non-motile cells flourishing in spring and motile community dominating during summer. The zooplankton community is dominated by active feeding-current feeders with peak biomass in the late spring declining during summer. The model reveals how zooplankton grazing reinforces protist plankton seasonal...

Different patterns of auditory cortex activation revealed by functional magnetic resonance imaging

Energy Technology Data Exchange (ETDEWEB)

Formisano, E; Pepino, A; Bracale, M [Department of Electronic Engineering, Biomedical Unit, Universita di Napoli, Federic II, Italy, Via Claudio 21, 80125 Napoli (Italy); Di Salle, F [Department of Biomorphological and Functional Sciences, Radiologucal Unit, Universita di Napoli, Federic II, Italy, Via Claudio 21, 80125 Napoli (Italy); Lanfermann, H; Zanella, F E [Department of Neuroradiology, J.W. Goethe Universitat, Frankfurt/M. (Germany)

1999-12-31

In the last few years, functional Magnetic Resonance Imaging (fMRI) has been widely accepted as an effective tool for mapping brain activities in both the sensorimotor and the cognitive field. The present work aims to assess the possibility of using fMRI methods to study the cortical response to different acoustic stimuli. Furthermore, we refer to recent data collected at Frankfurt University on the cortical pattern of auditory hallucinations. Healthy subjects showed broad bilateral activation, mostly located in the transverse gyrus of Heschl. The analysis of the cortical activation induced by different stimuli has pointed out a remarkable difference in the spatial and temporal features of the auditory cortex response to pulsed tones and pure tones. The activated areas during episodes of auditory hallucinations match the location of primary auditory cortex as defined in control measurements with the same patients and in the experiments on healthy subjects. (authors) 17 refs., 4 figs.

Loss of mitogen-activated protein kinase kinase kinase 4 (MAP3K4 reveals a requirement for MAPK signalling in mouse sex determination.

Directory of Open Access Journals (Sweden)

Debora Bogani

2009-09-01

Full Text Available Sex determination in mammals is controlled by the presence or absence of the Y-linked gene SRY. In the developing male (XY gonad, sex-determining region of the Y (SRY protein acts to up-regulate expression of the related gene, SOX9, a transcriptional regulator that in turn initiates a downstream pathway of testis development, whilst also suppressing ovary development. Despite the requirement for a number of transcription factors and secreted signalling molecules in sex determination, intracellular signalling components functioning in this process have not been defined. Here we report a role for the phylogenetically ancient mitogen-activated protein kinase (MAPK signalling pathway in mouse sex determination. Using a forward genetic screen, we identified the recessive boygirl (byg mutation. On the C57BL/6J background, embryos homozygous for byg exhibit consistent XY gonadal sex reversal. The byg mutation is an A to T transversion causing a premature stop codon in the gene encoding MAP3K4 (also known as MEKK4, a mitogen-activated protein kinase kinase kinase. Analysis of XY byg/byg gonads at 11.5 d post coitum reveals a growth deficit and a failure to support mesonephric cell migration, both early cellular processes normally associated with testis development. Expression analysis of mutant XY gonads at the same stage also reveals a dramatic reduction in Sox9 and, crucially, Sry at the transcript and protein levels. Moreover, we describe experiments showing the presence of activated MKK4, a direct target of MAP3K4, and activated p38 in the coelomic region of the XY gonad at 11.5 d post coitum, establishing a link between MAPK signalling in proliferating gonadal somatic cells and regulation of Sry expression. Finally, we provide evidence that haploinsufficiency for Map3k4 accounts for T-associated sex reversal (Tas. These data demonstrate that MAP3K4-dependent signalling events are required for normal expression of Sry during testis development, and

Loss of Mitogen-Activated Protein Kinase Kinase Kinase 4 (MAP3K4) Reveals a Requirement for MAPK Signalling in Mouse Sex Determination

Science.gov (United States)

Bogani, Debora; Siggers, Pam; Brixey, Rachel; Warr, Nick; Beddow, Sarah; Edwards, Jessica; Williams, Debbie; Wilhelm, Dagmar; Koopman, Peter; Flavell, Richard A.; Chi, Hongbo; Ostrer, Harry; Wells, Sara; Cheeseman, Michael; Greenfield, Andy

2009-01-01

Sex determination in mammals is controlled by the presence or absence of the Y-linked gene SRY. In the developing male (XY) gonad, sex-determining region of the Y (SRY) protein acts to up-regulate expression of the related gene, SOX9, a transcriptional regulator that in turn initiates a downstream pathway of testis development, whilst also suppressing ovary development. Despite the requirement for a number of transcription factors and secreted signalling molecules in sex determination, intracellular signalling components functioning in this process have not been defined. Here we report a role for the phylogenetically ancient mitogen-activated protein kinase (MAPK) signalling pathway in mouse sex determination. Using a forward genetic screen, we identified the recessive boygirl (byg) mutation. On the C57BL/6J background, embryos homozygous for byg exhibit consistent XY gonadal sex reversal. The byg mutation is an A to T transversion causing a premature stop codon in the gene encoding MAP3K4 (also known as MEKK4), a mitogen-activated protein kinase kinase kinase. Analysis of XY byg/byg gonads at 11.5 d post coitum reveals a growth deficit and a failure to support mesonephric cell migration, both early cellular processes normally associated with testis development. Expression analysis of mutant XY gonads at the same stage also reveals a dramatic reduction in Sox9 and, crucially, Sry at the transcript and protein levels. Moreover, we describe experiments showing the presence of activated MKK4, a direct target of MAP3K4, and activated p38 in the coelomic region of the XY gonad at 11.5 d post coitum, establishing a link between MAPK signalling in proliferating gonadal somatic cells and regulation of Sry expression. Finally, we provide evidence that haploinsufficiency for Map3k4 accounts for T-associated sex reversal (Tas). These data demonstrate that MAP3K4-dependent signalling events are required for normal expression of Sry during testis development, and create a novel

Prezidentské volby v USA: předvolební kampaň Baracka Obamy

OpenAIRE

Hronová, Lada

2011-01-01

Barack Obama's theme of candidature for President of United States of America, campaigning and then succesfuly won presidential election have became milestone in american history, when the afroamerican president has been elected for the first time. When candidate in primaries with Democratic Party or in final fase of presidental election against his republican competitor John McCain Barack Obama became well admired by american and also world public. Unmistakably important role had common unpo...

Aiming Airsea Battle: An Operational Concept To Counter China’s Maritime Area Denial Capabilities

Science.gov (United States)

2011-06-18

unnamed great power: “To protect Germany’s sea trade and colonies in the existing circumstances there is only one means – Germany must have a battle...with friends and allies, but by ourselves if we must.24 As multiple analysts have noted, the unnamed adversary alluded to here is unmistakably...21 Rory Medcalf, “Chinese Ghost Story,” The Diplomat, February 14, 2008. 22 Ibid. 23 Donn A. Starry, “US and Federal

Multichannel detrended fluctuation analysis reveals synchronized patterns of spontaneous spinal activity in anesthetized cats.

Directory of Open Access Journals (Sweden)

Erika E Rodríguez

Full Text Available The analysis of the interaction and synchronization of relatively large ensembles of neurons is fundamental for the understanding of complex functions of the nervous system. It is known that the temporal synchronization of neural ensembles is involved in the generation of specific motor, sensory or cognitive processes. Also, the intersegmental coherence of spinal spontaneous activity may indicate the existence of synaptic neural pathways between different pairs of lumbar segments. In this study we present a multichannel version of the detrended fluctuation analysis method (mDFA to analyze the correlation dynamics of spontaneous spinal activity (SSA from time series analysis. This method together with the classical detrended fluctuation analysis (DFA were used to find out whether the SSA recorded in one or several segments in the spinal cord of the anesthetized cat occurs either in a random or in an organized manner. Our results are consistent with a non-random organization of the sets of neurons involved in the generation of spontaneous cord dorsum potentials (CDPs recorded either from one lumbar segment (DFA-α mean = 1.04[Formula: see text]0.09 or simultaneously from several lumbar segments (mDFA-α mean = 1.01[Formula: see text]0.06, where α = 0.5 indicates randomness while α = 0.5 indicates long-term correlations. To test the sensitivity of the mDFA method we also examined the effects of small spinal lesions aimed to partially interrupt connectivity between neighboring lumbosacral segments. We found that the synchronization and correlation between the CDPs recorded from the L5 and L6 segments in both sides of the spinal cord were reduced when a lesion comprising the left dorsal quadrant was performed between the segments L5 and L6 (mDFA-[Formula: see text] = 0.992 as compared to initial conditions mDFA-α = 1.186. The synchronization and correlation were reduced even further after a similar additional right spinal lesion (mDFA-α = 0

Kaposiform hemangioendothelioma of the spleen in an adult: an initial case report.

Science.gov (United States)

Yu, Lu; Yang, Shou Jing

2011-12-01

Kaposiform hemangioendothelioma (KHE) is a rare locally aggressive vascular neoplasm characterized by infiltrating nodules and sheets of spindle cells, and unmistakable resemblance to Kaposi's sarcoma. KHE occurs mainly in newborns and infants and presents most commonly in the skin, deep soft tissue, and bone. We report a case of KHE in a 36-year-old female who presented with a spleen mass and underwent splenectomy. Macroscopic examination revealed a large, dark-red, firm mass in the spleen. Histologically, the tumor consisted of irregular, infiltrating nodules of densely packed spindle-shaped tumor cells closely associated with small slit-like and sieve-like blood vessels, which were separated with hyalinized hypocellular fibrous stroma. Immunohistochemically, both spindle and epithelioid cells were positive for CD34, CD31, and vimentin, but negative for EMA, cytokeratin, CD21, CD35, CD1a, and S-100 protein. The well-formed capillaries and mature vessels but not spindle tumor cell showed reactivity for factor VIII- related antigen. Alpha-Smooth muscle actin was detected in pericytes surrounding small round or slit-like capillaries. The final histologic diagnosis was KHE. Follow-up 6 month after operation revealed no sign of recurrence or metastasis.To the best of our knowledge, this is the first report of KHE arising in the spleen.

Why do young adults develop a passion for Internet activities? The associations among personality, revealing "true self" on the Internet, and passion for the Internet.

Science.gov (United States)

Tosun, Leman Pinar; Lajunen, Timo

2009-08-01

This study examines the associations of harmonious passion (HP) and obsessive passion (OP) for Internet activities with Eysenckian personality dimensions in a sample of 421 university students. Results show that psychoticism correlates positively with both HP and OP; extroversion correlates positively with HP only; and neuroticism has no correlation with passion for Internet activities. Additionally, the study examines participants' tendency to express their "true self" on the Internet, and the results reveal that this tendency has a positive association with psychoticism, neuroticism, and both types of passion for the Internet. Moreover, the relationship between psychoticism and passion (both harmonious and obsessive) is mediated by the tendency to express true self on the Internet. The results were interpreted from the media dependency perspective.

Epitope mapping for monoclonal antibody reveals the activation mechanism for αVβ3 integrin.

Directory of Open Access Journals (Sweden)

Tetsuji Kamata

Full Text Available Epitopes for a panel of anti-αVβ3 monoclonal antibodies (mAbs were investigated to explore the activation mechanism of αVβ3 integrin. Experiments utilizing αV/αIIb domain-swapping chimeras revealed that among the nine mAbs tested, five recognized the ligand-binding β-propeller domain and four recognized the thigh domain, which is the upper leg of the αV chain. Interestingly, the four mAbs included function-blocking as well as non-functional mAbs, although they bound at a distance from the ligand-binding site. The epitopes for these four mAbs were further determined using human-to-mouse αV chimeras. Among the four, P3G8 recognized an amino acid residue, Ser-528, located on the side of the thigh domain, while AMF-7, M9, and P2W7 all recognized a common epitope, Ser-462, that was located close to the α-genu, where integrin makes a sharp bend in the crystal structure. Fibrinogen binding studies for cells expressing wild-type αVβ3 confirmed that AMF-7, M9, and P2W7 were inhibitory, while P3G8 was non-functional. However, these mAbs were all unable to block binding when αVβ3 was constrained in its extended conformation. These results suggest that AMF-7, M9, and P2W7 block ligand binding allosterically by stabilizing the angle of the bend in the bent conformation. Thus, a switchblade-like movement of the integrin leg is indispensable for the affinity regulation of αVβ3 integrin.

Characterization of the active microbiotas associated with honey bees reveals healthier and broader communities when colonies are genetically diverse.

Directory of Open Access Journals (Sweden)

Heather R Mattila

Full Text Available Recent losses of honey bee colonies have led to increased interest in the microbial communities that are associated with these important pollinators. A critical function that bacteria perform for their honey bee hosts, but one that is poorly understood, is the transformation of worker-collected pollen into bee bread, a nutritious food product that can be stored for long periods in colonies. We used 16S rRNA pyrosequencing to comprehensively characterize in genetically diverse and genetically uniform colonies the active bacterial communities that are found on honey bees, in their digestive tracts, and in bee bread. This method provided insights that have not been revealed by past studies into the content and benefits of honey bee-associated microbial communities. Colony microbiotas differed substantially between sampling environments and were dominated by several anaerobic bacterial genera never before associated with honey bees, but renowned for their use by humans to ferment food. Colonies with genetically diverse populations of workers, a result of the highly promiscuous mating behavior of queens, benefited from greater microbial diversity, reduced pathogen loads, and increased abundance of putatively helpful bacteria, particularly species from the potentially probiotic genus Bifidobacterium. Across all colonies, Bifidobacterium activity was negatively correlated with the activity of genera that include pathogenic microbes; this relationship suggests a possible target for understanding whether microbes provide protective benefits to honey bees. Within-colony diversity shapes microbiotas associated with honey bees in ways that may have important repercussions for colony function and health. Our findings illuminate the importance of honey bee-bacteria symbioses and examine their intersection with nutrition, pathogen load, and genetic diversity, factors that are considered key to understanding honey bee decline.

BOLD Imaging in Awake Wild-Type and Mu-Opioid Receptor Knock-Out Mice Reveals On-Target Activation Maps in Response to Oxycodone

Directory of Open Access Journals (Sweden)

Kelsey Moore

2016-11-01

Full Text Available Blood oxygen level dependent (BOLD imaging in awake mice was used to identify differences in brain activity between wild-type, and Mu (µ opioid receptor knock-outs (MuKO in response to oxycodone (OXY. Using a segmented, annotated MRI mouse atlas and computational analysis, patterns of integrated positive and negative BOLD activity were identified across 122 brain areas. The pattern of positive BOLD showed enhanced activation across the brain in WT mice within 15 min of intraperitoneal administration of 2.5 mg of OXY. BOLD activation was detected in 72 regions out of 122, and was most prominent in areas of high µ opioid receptor density (thalamus, ventral tegmental area, substantia nigra, caudate putamen, basal amygdala and hypothalamus, and focus on pain circuits indicated strong activation in major pain processing centers (central amygdala, solitary tract, parabrachial area, insular cortex, gigantocellularis area, ventral thalamus primary sensory cortex and prelimbic cortex. Importantly, the OXY-induced positive BOLD was eliminated in MuKO mice in most regions, with few exceptions (some cerebellar nuclei, CA3 of the hippocampus, medial amygdala and preoptic areas. This result indicates that most effects of OXY on positive BOLD are mediated by the µ opioid receptor (on-target effects. OXY also caused an increase in negative BOLD in WT mice in few regions (16 out of 122 and, unlike the positive BOLD response the negative BOLD was only partially eliminated in the MuKO mice (cerebellum, and in some case intensified (hippocampus. Negative BOLD analysis therefore shows activation and deactivation events in the absence of the µ receptor for some areas where receptor expression is normally extremely low or absent (off-target effects. Together, our approach permits establishing opioid-induced BOLD activation maps in awake mice. In addition, comparison of WT and MuKO mutant mice reveals both on-target and off-target activation events, and set an OXY

KMOS{sup 3D} Reveals Low-level Star Formation Activity in Massive Quiescent Galaxies at 0.7 < z < 2.7

Energy Technology Data Exchange (ETDEWEB)

Belli, Sirio; Genzel, Reinhard; Förster Schreiber, Natascha M.; Wisnioski, Emily; Wilman, David J.; Mendel, J. Trevor; Beifiori, Alessandra; Bender, Ralf; Burkert, Andreas; Chan, Jeffrey; Davies, Rebecca L.; Davies, Ric; Fabricius, Maximilian; Fossati, Matteo; Galametz, Audrey; Lang, Philipp; Lutz, Dieter [Max-Planck-Institut für Extraterrestrische Physik (MPE), Giessenbachstr. 1, D-85748 Garching (Germany); Wuyts, Stijn [Department of Physics, University of Bath, Claverton Down, Bath, BA2 7AY (United Kingdom); Brammer, Gabriel B.; Momcheva, Ivelina G. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); and others

2017-05-20

We explore the H α emission in the massive quiescent galaxies observed by the KMOS{sup 3D} survey at 0.7 < z < 2.7. The H α line is robustly detected in 20 out of 120 UVJ -selected quiescent galaxies, and we classify the emission mechanism using the H α line width and the [N ii]/H α line ratio. We find that AGNs are likely to be responsible for the line emission in more than half of the cases. We also find robust evidence for star formation activity in nine quiescent galaxies, which we explore in detail. The H α kinematics reveal rotating disks in five of the nine galaxies. The dust-corrected H α star formation rates are low (0.2–7 M {sub ⊙} yr{sup −1}), and place these systems significantly below the main sequence. The 24 μ m-based, infrared luminosities, instead, overestimate the star formation rates. These galaxies present a lower gas-phase metallicity compared to star-forming objects with similar stellar mass, and many of them have close companions. We therefore conclude that the low-level star formation activity in these nine quiescent galaxies is likely to be fueled by inflowing gas or minor mergers, and could be a sign of rejuvenation events.

h5-HT(1B) receptor-mediated constitutive Galphai3-protein activation in stably transfected Chinese hamster ovary cells: an antibody capture assay reveals protean efficacy of 5-HT.

Science.gov (United States)

Newman-Tancredi, Adrian; Cussac, Didier; Marini, Laetitia; Touzard, Manuelle; Millan, Mark J

2003-03-01

1. Serotonin 5-HT(1B) receptors couple to G-proteins of the Gi/o family. However, their activation of specific G-protein subtypes is poorly characterised. Using an innovative antibody capture/guanosine-5'-0-(3-[(35)S]thio)-triphosphate ([(35)S]GTPgammaS) binding strategy, we characterised Galpha(i3) subunit activation by h5-HT(1B) receptors stably expressed in Chinese hamster ovary (CHO) cells. 2. The agonists, 5-HT, alniditan and BMS181,101, stimulated Galpha(i3), whereas methiothepin and SB224,289 behaved as inverse agonists. The selective 5-HT(1B) receptor ligand, S18127, modestly stimulated Galpha(i3) and reversed the actions of both 5-HT and methiothepin. S18127 (1 micro M) also produced parallel, dextral shifts of the 5-HT and methiothepin isotherms. 3. Isotopic dilution experiments ([(35)S]GTPgammaS versus GTPgammaS) revealed high-affinity [(35)S]GTPgammaS binding to Galpha(i3) subunits in the absence of receptor ligands indicating constitutive activity. High-affinity [(35)S]GTPgammaS binding was increased 2.8-fold by 5-HT with an increase in the affinity of GTPgammaS for Galpha(i3) subunits. In contrast, methiothepin halved the number of high-affinity binding sites and decreased their affinity. 4. h5-HT(1B) receptor-mediated Galpha(i3) subunit activation was dependent on the concentration of NaCl. At 300 mM, 5-HT stimulated [(35)S]GTPgammaS binding, basal Galpha(i3) activation was low and methiothepin was inactive. In contrast, at 10 mM NaCl, basal activity was enhanced and the inverse agonist activity of methiothepin was accentuated. Under these conditions, 5-HT decreased Galpha(i3) activation. 5. In conclusion, at h5-HT(1B) receptors expressed in CHO cells: (i) inverse agonist induced inhibition of Galpha(i3), and its reversal by S18127, reveals constitutive activation of this Galpha subunit; (ii) constitutive Galpha(i3) activation can be quantified by isotopic dilution [(35)S]GTPgammaS binding and (iii) decreasing NaCl concentrations enhances Galpha(i3

Problem situations in management activity

OpenAIRE

N.A. DUBINKO

2009-01-01

This article reviews contemporary methodological and theoretical approaches to the problem situations in management activity. Revealed and analyzed the types of problem situations managers dealing with in their activity. Rank correlation of problem situations shows distinctions depending on management work experience. Revealed gender distinctions in the managers' ideas of management problems.

Transcriptional response of zebrafish embryos exposed to neurotoxic compounds reveals a muscle activity dependent hspb11 expression.

Directory of Open Access Journals (Sweden)

Nils Klüver

Full Text Available Acetylcholinesterase (AChE inhibitors are widely used as pesticides and drugs. Their primary effect is the overstimulation of cholinergic receptors which results in an improper muscular function. During vertebrate embryonic development nerve activity and intracellular downstream events are critical for the regulation of muscle fiber formation. Whether AChE inhibitors and related neurotoxic compounds also provoke specific changes in gene transcription patterns during vertebrate development that allow them to establish a mechanistic link useful for identification of developmental toxicity pathways has, however, yet not been investigated. Therefore we examined the transcriptomic response of a known AChE inhibitor, the organophosphate azinphos-methyl (APM, in zebrafish embryos and compared the response with two non-AChE inhibiting unspecific control compounds, 1,4-dimethoxybenzene (DMB and 2,4-dinitrophenol (DNP. A highly specific cluster of APM induced gene transcripts was identified and a subset of strongly regulated genes was analyzed in more detail. The small heat shock protein hspb11 was found to be the most sensitive induced gene in response to AChE inhibitors. Comparison of expression in wildtype, ache and sop(fixe mutant embryos revealed that hspb11 expression was dependent on the nicotinic acetylcholine receptor (nAChR activity. Furthermore, modulators of intracellular calcium levels within the whole embryo led to a transcriptional up-regulation of hspb11 which suggests that elevated intracellular calcium levels may regulate the expression of this gene. During early zebrafish development, hspb11 was specifically expressed in muscle pioneer cells and Hspb11 morpholino-knockdown resulted in effects on slow muscle myosin organization. Our findings imply that a comparative toxicogenomic approach and functional analysis can lead to the identification of molecular mechanisms and specific marker genes for potential neurotoxic compounds.

Altered spontaneous activity in anisometropic amblyopia subjects: revealed by resting-state FMRI.

Directory of Open Access Journals (Sweden)

Xiaoming Lin

Full Text Available Amblyopia, also known as lazy eye, usually occurs during early childhood and results in poor or blurred vision. Recent neuroimaging studies have found cortical structural/functional abnormalities in amblyopia. However, until now, it was still not known whether the spontaneous activity of the brain changes in amblyopia subjects. In the present study, regional homogeneity (ReHo, a measure of the homogeneity of functional magnetic resonance imaging signals, was used for the first time to investigate changes in resting-state local spontaneous brain activity in individuals with anisometropic amblyopia. Compared with age- and gender-matched subjects with normal vision, the anisometropic amblyopia subjects showed decreased ReHo of spontaneous brain activity in the right precuneus, the left medial prefrontal cortex, the left inferior frontal gyrus, and the left cerebellum, and increased ReHo of spontaneous brain activity was found in the bilateral conjunction area of the postcentral and precentral gyri, the left paracentral lobule, the left superior temporal gyrus, the left fusiform gyrus, the conjunction area of the right insula, putamen and the right middle occipital gyrus. The observed decreases in ReHo may reflect decreased visuo-motor processing ability, and the increases in ReHo in the somatosensory cortices, the motor areas and the auditory area may indicate compensatory plasticity in amblyopia.

Billionaire Entrepreneurs: A Systematic Analysis

OpenAIRE

Henrekson, Magnus; Sanandaji, Tino

2013-01-01

The overwhelming majority of self-employed individuals are not entrepreneurial in the Schumpeterian sense. In order to unmistakably identify Schumpeterian entrepreneurs we focus on self-made billionaires (in USD) on Forbes Magazine’s list who became wealthy by founding new firms. In this way we identify 996 billionaire entrepreneurs in over fifty countries in the 1996–2010 period. To our knowledge this is the first systematic cross-country study of billionaire entrepreneurs, an economically i...

The Limits of Judicial Persuasion and the Fragility of Judicial Legitimacy

OpenAIRE

Egan, Patrick J; Citrin, Jack

2011-01-01

Experimental research has yielded findings that are largely optimistic about the Court’s powers to move public attitudes. But left largely unexplored is whether the Court’s pronouncements simultaneously cause the Court to lose support among those who disagree with it. Here we explore these questions using a two-wave survey experiment with a nationally representative sample of Americans. We find that learning of the Court’s rulings moves opinion toward the Court in an unmistakable fashion in o...

The Theory of Unconventional Warfare: Win, Lose, and Draw

Science.gov (United States)

2008-12-01

addition, Taraki changed the flag from its Islamic black- green -red colors to a 22 Soviet inspired all red color and then proceeded to paint most of...5. Introduction of the Stinger: 26 September 1986 The unmistakable backfire signature of an American made FIM -92 Stinger anti- aircraft missile...movements to the Bolivian Army. The 2nd Bolivian Ranger Battalion was deployed as a screen to trap Che’s men as the 8th Bolivian Army Division

Changes in Male Rat Sexual Behavior and Brain Activity Revealed by Functional Magnetic Resonance Imaging in Response to Chronic Mild Stress.

Science.gov (United States)

Chen, Guotao; Yang, Baibing; Chen, Jianhuai; Zhu, Leilei; Jiang, Hesong; Yu, Wen; Zang, Fengchao; Chen, Yun; Dai, Yutian

2018-02-01

G, Yang B, Chen J, et al. Changes in Male Rat Sexual Behavior and Brain Activity Revealed by Functional Magnetic Resonance Imaging in Response to Chronic Mild Stress. J Sex Med 2018;15:136-147. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Research activities in the use of energy; Actividades de investigacion en el uso de la energia electrica

Energy Technology Data Exchange (ETDEWEB)

Covarrubias Ramos, Rogelio; Garcia Juarez, Francisco [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

1999-12-31

The use of energy is intimately related to the development and is found in the human activities of all types, consequently we could say that to a greater usage it must correspond a greater benefit. This paper carries on a comparative analysis of the Mexico`s energy efficiency versus industrialized countries; this analysis shows that while Mexico indicates a growing tendency, in the industrialized countries the tendency is to the drop, unmistakable sign of a better usage of the energy sources. It also makes evident that promoting the energy efficiency in Mexico will stimulate and regulate the energy conservation at National level, in the same way it is mentioned that an appropriate energy demand Management for the users as well as for the service providers, will diminish the peak demand, the adequate application of the electric rates at the actual conditions and the energy saving and the strategic load growth [Espanol] El uso de la energia esta intimamente relacionado con el desarrollo y se encuentra en las actividades humanas de todo tipo, de tal suerte que podriamos decir que a mayor uso debe corresponder un mayor beneficio. En este documento se realiza un analisis comparativo de la eficiencia energetica en Mexico contra paises industrializados; este analisis muestra que mientras Mexico indica una tendencia creciente, en los paises industrializados la tendencia es a la baja, signo inequivoco de un mejor uso de los energeticos, tambien hace ver que la promocion de la eficiencia energetica en Mexico estimulara y regulara el ahorro de energia a nivel nacional, de igual manera se menciona que una buena administracion de la demanda energetica tanto por los usuarios como los que prestan el servicio, reducira la demanda pico, la adecuacion de las tarifas electricas a las condiciones reales y el ahorro de los energeticos y el crecimiento estrategico de la carga

Research activities in the use of energy; Actividades de investigacion en el uso de la energia electrica

Energy Technology Data Exchange (ETDEWEB)

Covarrubias Ramos, Rogelio; Garcia Juarez, Francisco [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

1998-12-31

The use of energy is intimately related to the development and is found in the human activities of all types, consequently we could say that to a greater usage it must correspond a greater benefit. This paper carries on a comparative analysis of the Mexico`s energy efficiency versus industrialized countries; this analysis shows that while Mexico indicates a growing tendency, in the industrialized countries the tendency is to the drop, unmistakable sign of a better usage of the energy sources. It also makes evident that promoting the energy efficiency in Mexico will stimulate and regulate the energy conservation at National level, in the same way it is mentioned that an appropriate energy demand Management for the users as well as for the service providers, will diminish the peak demand, the adequate application of the electric rates at the actual conditions and the energy saving and the strategic load growth [Espanol] El uso de la energia esta intimamente relacionado con el desarrollo y se encuentra en las actividades humanas de todo tipo, de tal suerte que podriamos decir que a mayor uso debe corresponder un mayor beneficio. En este documento se realiza un analisis comparativo de la eficiencia energetica en Mexico contra paises industrializados; este analisis muestra que mientras Mexico indica una tendencia creciente, en los paises industrializados la tendencia es a la baja, signo inequivoco de un mejor uso de los energeticos, tambien hace ver que la promocion de la eficiencia energetica en Mexico estimulara y regulara el ahorro de energia a nivel nacional, de igual manera se menciona que una buena administracion de la demanda energetica tanto por los usuarios como los que prestan el servicio, reducira la demanda pico, la adecuacion de las tarifas electricas a las condiciones reales y el ahorro de los energeticos y el crecimiento estrategico de la carga

h5-HT1B receptor-mediated constitutive Gαi3-protein activation in stably transfected Chinese hamster ovary cells: an antibody capture assay reveals protean efficacy of 5-HT

Science.gov (United States)

Newman-Tancredi, Adrian; Cussac, Didier; Marini, Laetitia; Touzard, Manuelle; Millan, Mark J

2003-01-01

Serotonin 5-HT1B receptors couple to G-proteins of the Gi/o family. However, their activation of specific G-protein subtypes is poorly characterised. Using an innovative antibody capture/guanosine-5′-0-(3-[35S]thio)-triphosphate ([35S]GTPγS) binding strategy, we characterised Gαi3 subunit activation by h5-HT1B receptors stably expressed in Chinese hamster ovary (CHO) cells. The agonists, 5-HT, alniditan and BMS181,101, stimulated Gαi3, whereas methiothepin and SB224,289 behaved as inverse agonists. The selective 5-HT1B receptor ligand, S18127, modestly stimulated Gαi3 and reversed the actions of both 5-HT and methiothepin. S18127 (1 μM) also produced parallel, dextral shifts of the 5-HT and methiothepin isotherms. Isotopic dilution experiments ([35S]GTPγS versus GTPγS) revealed high-affinity [35S]GTPγS binding to Gαi3 subunits in the absence of receptor ligands indicating constitutive activity. High-affinity [35S]GTPγS binding was increased 2.8-fold by 5-HT with an increase in the affinity of GTPγS for Gαi3 subunits. In contrast, methiothepin halved the number of high-affinity binding sites and decreased their affinity. h5-HT1B receptor-mediated Gαi3 subunit activation was dependent on the concentration of NaCl. At 300 mM, 5-HT stimulated [35S]GTPγS binding, basal Gαi3 activation was low and methiothepin was inactive. In contrast, at 10 mM NaCl, basal activity was enhanced and the inverse agonist activity of methiothepin was accentuated. Under these conditions, 5-HT decreased Gαi3 activation. In conclusion, at h5-HT1B receptors expressed in CHO cells: (i) inverse agonist induced inhibition of Gαi3, and its reversal by S18127, reveals constitutive activation of this Gα subunit; (ii) constitutive Gαi3 activation can be quantified by isotopic dilution [35S]GTPγS binding and (iii) decreasing NaCl concentrations enhances Gαi3 activation and leads to protean agonist properties of 5-HT: that is a switch to inhibition of Gαi3. PMID:12684263

How community environment shapes physical activity: perceptions revealed through the PhotoVoice method.

Science.gov (United States)

Belon, Ana Paula; Nieuwendyk, Laura M; Vallianatos, Helen; Nykiforuk, Candace I J

2014-09-01

A growing body of evidence shows that community environment plays an important role in individuals' physical activity engagement. However, while attributes of the physical environment are widely investigated, sociocultural, political, and economic aspects of the environment are often neglected. This article helps to fill these knowledge gaps by providing a more comprehensive understanding of multiple dimensions of the community environment relative to physical activity. The purpose of this study was to qualitatively explore how people's experiences and perceptions of their community environments affect their abilities to engage in physical activity. A PhotoVoice method was used to identify barriers to and opportunities for physical activity among residents in four communities in the province of Alberta, Canada, in 2009. After taking pictures, the thirty-five participants shared their perceptions of those opportunities and barriers in their community environments during individual interviews. Using the Analysis Grid for Environments Linked to Obesity (ANGELO) framework, themes emerging from these photo-elicited interviews were organized in four environment types: physical, sociocultural, economic, and political. The data show that themes linked to the physical (56.6%) and sociocultural (31.4%) environments were discussed more frequently than the themes of the economic (5.9%) and political (6.1%) environments. Participants identified nuanced barriers and opportunities for physical activity, which are illustrated by their quotes and photographs. The findings suggest that a myriad of factors from physical, sociocultural, economic, and political environments influence people's abilities to be physically active in their communities. Therefore, adoption of a broad, ecological perspective is needed to address the barriers and build upon the opportunities described by participants to make communities more healthy and active. Copyright © 2014 Elsevier Ltd. All rights

Using Carbohydrate Interaction Assays to Reveal Novel Binding Sites in Carbohydrate Active Enzymes

DEFF Research Database (Denmark)

Cockburn, Darrell; Wilkens, Casper; Dilokpimol, Adiphol

2016-01-01

Carbohydrate active enzymes often contain auxiliary binding sites located either on independent domains termed carbohydrate binding modules (CBMs) or as so-called surface binding sites (SBSs) on the catalytic module at a certain distance from the active site. The SBSs are usually critical...

Combination of DTI and fMRI reveals the white matter changes correlating with the decline of default-mode network activity in Alzheimer's disease

Science.gov (United States)

Wu, Xianjun; Di, Qian; Li, Yao; Zhao, Xiaojie

2009-02-01

Recently, evidences from fMRI studies have shown that there was decreased activity among the default-mode network in Alzheimer's disease (AD), and DTI researches also demonstrated that demyelinations exist in white matter of AD patients. Therefore, combining these two MRI methods may help to reveal the relationship between white matter damages and alterations of the resting state functional connectivity network. In the present study, we tried to address this issue by means of correlation analysis between DTI and resting state fMRI images. The default-mode networks of AD and normal control groups were compared to find the areas with significantly declined activity firstly. Then, the white matter regions whose fractional anisotropy (FA) value correlated with this decline were located through multiple regressions between the FA values and the BOLD response of the default networks. Among these correlating white matter regions, those whose FA values also declined were found by a group comparison between AD patients and healthy elderly control subjects. Our results showed that the areas with decreased activity among default-mode network included left posterior cingulated cortex (PCC), left medial temporal gyrus et al. And the damaged white matter areas correlated with the default-mode network alterations were located around left sub-gyral temporal lobe. These changes may relate to the decreased connectivity between PCC and medial temporal lobe (MTL), and thus correlate with the deficiency of default-mode network activity.

Determination of the physiological 2:2 TLR5:flagellin activation stoichiometry revealed by the activity of a fusion receptor

International Nuclear Information System (INIS)

Ivičak-Kocjan, Karolina; Panter, Gabriela; Benčina, Mojca; Jerala, Roman

2013-01-01

Highlights: •The chimeric protein fusing flagellin to the TLR5 ectodomain is constitutively active. •Mutation P736H within the BB-loop of TLR5 TIR domain renders the receptor inactive. •The R90D mutation in flagellin inactivated autoactivation of the chimeric protein. •The 2:2 stoichiometry of the TLR5:flagellin complex is physiologically relevant. -- Abstract: Toll-like receptor 5 (TLR5) recognizes flagellin of most flagellated bacteria, enabling activation of the MyD88-dependent signaling pathway. The recently published crystal structure of a truncated zebrafish TLR5 ectodomain in complex with an inactive flagellin fragment indicated binding of two flagellin molecules to a TLR5 homodimer, however this complex did not dimerize in solution. In the present study, we aimed to determine the physiological stoichiometry of TLR5:flagellin activation by the use of a chimeric protein composed of an active flagellin fragment linked to the N-terminus of human TLR5 (SF-TLR5). This construct was constitutively active. Inactivation by the R90D mutation within flagellin demonstrated that autoactivation of the chimeric protein depended solely on the specific interaction between TLR5 and flagellin. Addition of wild-type hTLR5 substantially lowered autoactivation of SF-TLR5 in a concentration dependent manner, an effect which was reversible by the addition of exogenous Salmonella typhimurium flagellin, indicating the biological activity of a TLR5:flagellin complex with a 2:2 stoichiometry. These results, in addition to the combinations of inactive P736H mutation within the BB-loop of the TIR domain of TLR5 and SF-TLR5, further confirm the mechanism of TLR5 activation

Determination of the physiological 2:2 TLR5:flagellin activation stoichiometry revealed by the activity of a fusion receptor

Energy Technology Data Exchange (ETDEWEB)

Ivičak-Kocjan, Karolina; Panter, Gabriela; Benčina, Mojca [Laboratory of Biotechnology, National Institute of Chemistry, 1000 Ljubljana (Slovenia); The Centre of Excellence EN-FIST, 1000 Ljubljana (Slovenia); Jerala, Roman, E-mail: roman.jerala@ki.si [Laboratory of Biotechnology, National Institute of Chemistry, 1000 Ljubljana (Slovenia); The Centre of Excellence EN-FIST, 1000 Ljubljana (Slovenia); The Faculty of Chemistry and Chemical Technology, University of Ljubljana, 1000 Ljubljana (Slovenia)

2013-05-24

Highlights: •The chimeric protein fusing flagellin to the TLR5 ectodomain is constitutively active. •Mutation P736H within the BB-loop of TLR5 TIR domain renders the receptor inactive. •The R90D mutation in flagellin inactivated autoactivation of the chimeric protein. •The 2:2 stoichiometry of the TLR5:flagellin complex is physiologically relevant. -- Abstract: Toll-like receptor 5 (TLR5) recognizes flagellin of most flagellated bacteria, enabling activation of the MyD88-dependent signaling pathway. The recently published crystal structure of a truncated zebrafish TLR5 ectodomain in complex with an inactive flagellin fragment indicated binding of two flagellin molecules to a TLR5 homodimer, however this complex did not dimerize in solution. In the present study, we aimed to determine the physiological stoichiometry of TLR5:flagellin activation by the use of a chimeric protein composed of an active flagellin fragment linked to the N-terminus of human TLR5 (SF-TLR5). This construct was constitutively active. Inactivation by the R90D mutation within flagellin demonstrated that autoactivation of the chimeric protein depended solely on the specific interaction between TLR5 and flagellin. Addition of wild-type hTLR5 substantially lowered autoactivation of SF-TLR5 in a concentration dependent manner, an effect which was reversible by the addition of exogenous Salmonella typhimurium flagellin, indicating the biological activity of a TLR5:flagellin complex with a 2:2 stoichiometry. These results, in addition to the combinations of inactive P736H mutation within the BB-loop of the TIR domain of TLR5 and SF-TLR5, further confirm the mechanism of TLR5 activation.

Using activity triggered e-diaries to reveal the associations between physical activity and affective states in older adult's daily living.

Science.gov (United States)

Kanning, Martina; Ebner-Priemer, Ulrich; Schlicht, Wolfgang

2015-09-17

Evidence suggests that older adults show positive affects after participating in exercise bouts. However, it is less clear, if and how physical activities in daily living enhance affective states, too. This is dissatisfying, as most of older adults' physical activities are part of their daily living. To answer these questions we used activity-triggered e-diaries to investigate the within-subject effects of physical activity on three dimensions of affective states (valence, energetic arousal, calmness) during everyday life. Older adults (N = 74) between 50 and 70 years took part in the study during three consecutive days. Physical activity in daily living was objectively assessed using accelerometers. Affects were measured 10 min after a study participant surpassed a predefined threshold for activity or inactivity. The participants were prompted by an acoustic signal to assess their momentary affective states on an e-diary. Data were analyzed with hierarchical multilevel analyses. Whenever older individuals were more physically active, they felt more energized (energetic arousal) and agitated (calmness). However, they did not feel better (valence). Interestingly, body mass index (BMI) and valence were associated in a significant cross-level interaction. BMI acts as a moderating variable in the way that lower BMI scores were associated with higher levels of valence scores after being physically active. The innovative ambulatory assessment used here affords an interesting insight to the affective effects of daily activity of older adults. These effects are no simple and no linear ones, i.e. physical activity is not associated with positive affects per se as shown several times in experimental studies with single activity bouts. Rather there is a differentiating association seen as an enhanced feeling of energy and agitation, which is not accompanied by a better feeling. Socio-emotional selectivity theory may support the finding that older individuals are

Similar prefrontal cortical activities between general fluid intelligence and visuospatial working memory tasks in preschool children as revealed by optical topography.

Science.gov (United States)

Kuwajima, Mariko; Sawaguchi, Toshiyuki

2010-10-01

General fluid intelligence (gF) is a major component of intellect in both adults and children. Whereas its neural substrates have been studied relatively thoroughly in adults, those are poorly understood in children, particularly preschoolers. Here, we hypothesized that gF and visuospatial working memory share a common neural system within the lateral prefrontal cortex (LPFC) during the preschool years (4-6 years). At the behavioral level, we found that gF positively and significantly correlated with abilities (especially accuracy) in visuospatial working memory. Optical topography revealed that the LPFC of preschoolers was activated and deactivated during the visuospatial working memory task and the gF task. We found that the spatio-temporal features of neural activity in the LPFC were similar for both the visuospatial working memory task and the gF task. Further, 2 months of training for the visuospatial working memory task significantly increased gF in the preschoolers. These findings suggest that a common neural system in the LPFC is recruited to improve the visuospatial working memory and gF in preschoolers. Efficient recruitment of this neural system may be important for good performance in these functions in preschoolers, and behavioral training using this system would help to increase gF at these ages.

Dynamic Metabolomics Reveals that Insulin Primes the Adipocyte for Glucose Metabolism

Directory of Open Access Journals (Sweden)

James R. Krycer

2017-12-01

Full Text Available Insulin triggers an extensive signaling cascade to coordinate adipocyte glucose metabolism. It is considered that the major role of insulin is to provide anabolic substrates by activating GLUT4-dependent glucose uptake. However, insulin stimulates phosphorylation of many metabolic proteins. To examine the implications of this on glucose metabolism, we performed dynamic tracer metabolomics in cultured adipocytes treated with insulin. Temporal analysis of metabolite concentrations and tracer labeling revealed rapid and distinct changes in glucose metabolism, favoring specific glycolytic branch points and pyruvate anaplerosis. Integrating dynamic metabolomics and phosphoproteomics data revealed that insulin-dependent phosphorylation of anabolic enzymes occurred prior to substrate accumulation. Indeed, glycogen synthesis was activated independently of glucose supply. We refer to this phenomenon as metabolic priming, whereby insulin signaling creates a demand-driven system to “pull” glucose into specific anabolic pathways. This complements the supply-driven regulation of anabolism by substrate accumulation and highlights an additional role for insulin action in adipocyte glucose metabolism.

Alpha-Band Activity Reveals Spontaneous Representations of Spatial Position in Visual Working Memory.

Science.gov (United States)

Foster, Joshua J; Bsales, Emma M; Jaffe, Russell J; Awh, Edward

2017-10-23

An emerging view suggests that spatial position is an integral component of working memory (WM), such that non-spatial features are bound to locations regardless of whether space is relevant [1, 2]. For instance, past work has shown that stimulus position is spontaneously remembered when non-spatial features are stored. Item recognition is enhanced when memoranda appear at the same location where they were encoded [3-5], and accessing non-spatial information elicits shifts of spatial attention to the original position of the stimulus [6, 7]. However, these findings do not establish that a persistent, active representation of stimulus position is maintained in WM because similar effects have also been documented following storage in long-term memory [8, 9]. Here we show that the spatial position of the memorandum is actively coded by persistent neural activity during a non-spatial WM task. We used a spatial encoding model in conjunction with electroencephalogram (EEG) measurements of oscillatory alpha-band (8-12 Hz) activity to track active representations of spatial position. The position of the stimulus varied trial to trial but was wholly irrelevant to the tasks. We nevertheless observed active neural representations of the original stimulus position that persisted throughout the retention interval. Further experiments established that these spatial representations are dependent on the volitional storage of non-spatial features rather than being a lingering effect of sensory energy or initial encoding demands. These findings provide strong evidence that online spatial representations are spontaneously maintained in WM-regardless of task relevance-during the storage of non-spatial features. Copyright © 2017 Elsevier Ltd. All rights reserved.

Serine Proteolytic Pathway Activation Reveals an Expanded Ensemble of Wound Response Genes in Drosophila

Science.gov (United States)

Patterson, Rachel A.; Juarez, Michelle T.; Hermann, Anita; Sasik, Roman; Hardiman, Gary; McGinnis, William

2013-01-01

After injury to the animal epidermis, a variety of genes are transcriptionally activated in nearby cells to regenerate the missing cells and facilitate barrier repair. The range and types of diffusible wound signals that are produced by damaged epidermis and function to activate repair genes during epidermal regeneration remains a subject of very active study in many animals. In Drosophila embryos, we have discovered that serine protease function is locally activated around wound sites, and is also required for localized activation of epidermal repair genes. The serine protease trypsin is sufficient to induce a striking global epidermal wound response without inflicting cell death or compromising the integrity of the epithelial barrier. We developed a trypsin wounding treatment as an amplification tool to more fully understand the changes in the Drosophila transcriptome that occur after epidermal injury. By comparing our array results with similar results on mammalian skin wounding we can see which evolutionarily conserved pathways are activated after epidermal wounding in very diverse animals. Our innovative serine protease-mediated wounding protocol allowed us to identify 8 additional genes that are activated in epidermal cells in the immediate vicinity of puncture wounds, and the functions of many of these genes suggest novel genetic pathways that may control epidermal wound repair. Additionally, our data augments the evidence that clean puncture wounding can mount a powerful innate immune transcriptional response, with different innate immune genes being activated in an interesting variety of ways. These include puncture-induced activation only in epidermal cells in the immediate vicinity of wounds, or in all epidermal cells, or specifically in the fat body, or in multiple tissues. PMID:23637905

Xenobiotics and the Human Gut Microbiome: Metatranscriptomics Reveal the Active Players

OpenAIRE

Ursell, Luke K.; Knight, Rob

2013-01-01

The human gut microbiome plays an important role in the metabolism of xenobiotics. In a recent issue of Cell, Maurice et al. identify the active members of the gut microbiome and show how gene expression profiles change within the gut microbial community in response to antibiotics and host-targeted xenobiotics.

Basic Military Justice Handbook. Revision

Science.gov (United States)

1989-01-01

unmistakable odor of burning marijuana outside the accused’s barracks room, acted correctly when he demanded entry to the room and placed all occupants under...conspirator in furtherance of the conspiracy to be the act of all the conspirators. Suppose, therefore, that A and B agree to burn down the Naval Justice...September 19CY, without authority, fail to go at the time precribed to his appointed place of duty, to wit: the 0600 restricted muster on the fantail. (2

Seasonal deformation and active landslide thickness revealed by spaceborne InSAR observations: a case study of Crescent lake landslide, WA

Science.gov (United States)

Hu, X.; Lu, Z.; Pierson, T. C.; Kramer, R.

2017-12-01

Understanding the precipitation triggering mechanism and quantifying the creeping landslide thickness are important to conduct early warnings and estimate potential failure volume and runout extent. However, it is problematic to use traditional geodetic methods to identify the active landslide boundaries and capture the transient mobility over hilly and vegetated landslide landscape. Here we present a novel InSAR processing strategy to characterize the spatial distribution and temporal behavior of the landslide movement in response to precipitation over Crescent lake landslide, WA using spaceborne SAR data of ALOS-1 PALSAR-1, ALOS-2 PALSAR-2 and Sentinel-1A. Time-series measurements reveal the seasonal deformation of landslide lobe, showing a much larger magnitude compared to the motion at lower elevated terrain expressed by an off-slide GPS station, suggesting an amplified hydrological loading effect associated with thick unconsolidated zone. Thanks to the high temporal resolution of Sentinel-1A and on-slide GPS data, we capture the progressive incipient motions in the wet season, characterized by the elastic slope-normal contraction due to loading during antecedent rainfall, followed by downslope slip and lateral propagation in less than one-month intense precipitation, because the elevated pore pressure and the reduced friction at the basal instigate the shear motion. The proposed threshold precipitation concept, in terms of the intensity and duration, can be an integral part of the landslide warning system. The active thickness can be inverted using three-dimensional (3D) displacement map based on the principle of mass conservation. We extract quasi-3D displacements using two independent (ascending and descending) InSAR measurements assuming that the targets move exclusively along the aspect direction on the slope-parallel plane. This routine of the extraction of quasi-3D displacement and the inversion of active lobe thickness can be utilized in the study of

Equinoctial Activity Over Titan Dune Fields Revealed by Cassini/vims

Science.gov (United States)

Rodriguez, S.; Le Mouelic, S.; Barnes, J. W.; Hirtzig, M.; Rannou, P.; Sotin, C.; Brown, R. H.; Bow, J.; Vixie, G.; Cornet, T.; Bourgeois, O.; Narteau, C.; Courrech Du Pont, S.; Le Gall, A.; Reffet, E.; Griffith, C. A.; Jaumann, R.; Stephan, K.; Buratti, B. J.; Clark, R. N.; Baines, K. H.; Nicholson, P. D.; Coustenis, A.

2012-12-01

Titan, the largest satellite of Saturn, is the only satellite in the solar system with a dense atmosphere. The close and continuous observations of Titan by the Cassini spacecraft, in orbit around Saturn since July 2004, bring us evidences that Titan troposphere and low stratosphere experience an exotic, but complete meteorological cycle similar to the Earth hydrological cycle, with hydrocarbons evaporation, condensation in clouds, and rainfall. Cassini monitoring campaigns also demonstrate that Titan's cloud coverage and climate vary with latitude. Titan's tropics, with globally weak meteorological activity and widespread dune fields, seem to be slightly more arid than the poles, where extensive and numerous liquid reservoirs and sustained cloud activity have been discovered. Only a few tropo-spheric clouds have been observed at Titan's tropics during the southern summer. As equinox was approaching (in August 2009), they occurred more frequently and appeared to grow in strength and size. We present here the observation of intense brightening at Titan's tropics, very close to the equinox. These detections were conducted with the Visual and Infrared Mapping Spectrometer (VIMS) onboard Cassini. We will discuss the VIMS images of the three individual events detected so far, observed during the Titan's flybys T56 (22 May 2009), T65 (13 January 2010) and T70 (21 June 2010). T56, T65 and T70 observations show an intense and transient brighten-ing of large regions very close to the equator, right over the extensive dune fields of Senkyo, Belet and Shangri-La. They all appear spectrally and morphologically different from all transient surface features or atmospheric phenomena previously reported. Indeed, these events share in particular a strong brightening at wavelengths greater than 2 μm (especially at 5 μm), making them spectrally distinct from the small tropical clouds observed before the equinox and the large storms observed near the equator in September and October

Activation of auditory white matter tracts as revealed by functional magnetic resonance imaging

Energy Technology Data Exchange (ETDEWEB)

Tae, Woo Suk [Kangwon National University, Neuroscience Research Institute, School of Medicine, Chuncheon (Korea, Republic of); Yakunina, Natalia; Nam, Eui-Cheol [Kangwon National University, Neuroscience Research Institute, School of Medicine, Chuncheon (Korea, Republic of); Kangwon National University, Department of Otolaryngology, School of Medicine, Chuncheon, Kangwon-do (Korea, Republic of); Kim, Tae Su [Kangwon National University Hospital, Department of Otolaryngology, Chuncheon (Korea, Republic of); Kim, Sam Soo [Kangwon National University, Neuroscience Research Institute, School of Medicine, Chuncheon (Korea, Republic of); Kangwon National University, Department of Radiology, School of Medicine, Chuncheon (Korea, Republic of)

2014-07-15

The ability of functional magnetic resonance imaging (fMRI) to detect activation in brain white matter (WM) is controversial. In particular, studies on the functional activation of WM tracts in the central auditory system are scarce. We utilized fMRI to assess and characterize the entire auditory WM pathway under robust experimental conditions involving the acquisition of a large number of functional volumes, the application of broadband auditory stimuli of high intensity, and the use of sparse temporal sampling to avoid scanner noise effects and increase signal-to-noise ratio. Nineteen healthy volunteers were subjected to broadband white noise in a block paradigm; each run had four sound-on/off alternations and was repeated nine times for each subject. Sparse sampling (TR = 8 s) was used. In addition to traditional gray matter (GM) auditory center activation, WM activation was detected in the isthmus and midbody of the corpus callosum (CC), tapetum, auditory radiation, lateral lemniscus, and decussation of the superior cerebellar peduncles. At the individual level, 13 of 19 subjects (68 %) had CC activation. Callosal WM exhibited a temporal delay of approximately 8 s in response to the stimulation compared with GM. These findings suggest that direct evaluation of the entire functional network of the central auditory system may be possible using fMRI, which may aid in understanding the neurophysiological basis of the central auditory system and in developing treatment strategies for various central auditory disorders. (orig.)

Activation of auditory white matter tracts as revealed by functional magnetic resonance imaging

International Nuclear Information System (INIS)

Tae, Woo Suk; Yakunina, Natalia; Nam, Eui-Cheol; Kim, Tae Su; Kim, Sam Soo

2014-01-01

The ability of functional magnetic resonance imaging (fMRI) to detect activation in brain white matter (WM) is controversial. In particular, studies on the functional activation of WM tracts in the central auditory system are scarce. We utilized fMRI to assess and characterize the entire auditory WM pathway under robust experimental conditions involving the acquisition of a large number of functional volumes, the application of broadband auditory stimuli of high intensity, and the use of sparse temporal sampling to avoid scanner noise effects and increase signal-to-noise ratio. Nineteen healthy volunteers were subjected to broadband white noise in a block paradigm; each run had four sound-on/off alternations and was repeated nine times for each subject. Sparse sampling (TR = 8 s) was used. In addition to traditional gray matter (GM) auditory center activation, WM activation was detected in the isthmus and midbody of the corpus callosum (CC), tapetum, auditory radiation, lateral lemniscus, and decussation of the superior cerebellar peduncles. At the individual level, 13 of 19 subjects (68 %) had CC activation. Callosal WM exhibited a temporal delay of approximately 8 s in response to the stimulation compared with GM. These findings suggest that direct evaluation of the entire functional network of the central auditory system may be possible using fMRI, which may aid in understanding the neurophysiological basis of the central auditory system and in developing treatment strategies for various central auditory disorders. (orig.)

Correlations between human mobility and social interaction reveal general activity patterns

DEFF Research Database (Denmark)

Mollgaard, Anders; Jørgensen, Sune Lehmann; Mathiesen, Joachim

2017-01-01

A day in the life of a person involves a broad range of activities which are common across many people. Going beyond diurnal cycles, a central question is: to what extent do individuals act according to patterns shared across an entire population? Here we investigate the interplay between differe...... they be of social or of physical character....

Aromatic C-H bond activation revealed by infrared multiphoton dissociation spectroscopy

Czech Academy of Sciences Publication Activity Database

Jašíková, L.; Hanikýřová, E.; Schröder, Detlef; Roithová, J.

2012-01-01

Roč. 47, č. 4 (2012), s. 460-465 ISSN 1076-5174 Grant - others:GA ČR(CZ) GAP207/11/0338; Seventh Framework Program(XE) 226716 Institutional research plan: CEZ:AV0Z40550506 Keywords : C-H activation * density functional theory calculations * ion spectroscopy * metal oxides * rearrangements Subject RIV: CC - Organic Chemistry Impact factor: 3.214, year: 2012

Metabonomics revealed xanthine oxidase-induced oxidative stress and inflammation in the pathogenesis of diabetic nephropathy.

Science.gov (United States)

Liu, Jingping; Wang, Chengshi; Liu, Fang; Lu, Yanrong; Cheng, Jingqiu

2015-03-01

Diabetic nephropathy (DN) is a serious complication of diabetes mellitus (DM), which is a major public health problem in the world. To reveal the metabolic changes associated with DN, we analyzed the serum, urine, and renal extracts obtained from control and streptozotocin (STZ)-induced DN rats by (1)H NMR-based metabonomics and multivariate data analysis. A significant difference between control and DN rats was revealed in metabolic profiles, and we identified several important DN-related metabolites including increased levels of allantoin and uric acid (UA) in the DN rats, suggesting that disturbed purine metabolism may be involved in the DN. Combined with conventional histological and biological methods, we further demonstrated that xanthine oxidase (XO), a key enzyme for purine catabolism, was abnormally activated in the kidney of diabetic rats by hyperglycemia. The highly activated XO increased the level of intracellular ROS, which caused renal injury by direct oxidative damage to renal cells, and indirect inducing inflammatory responses via activating NF-κB signaling pathway. Our study highlighted that metabonomics is a promising tool to reveal the metabolic changes and the underlying mechanism involved in the pathogenesis of DN.

Spontaneous cortical activity reveals hallmarks of an optimal internal model of the environment.

Science.gov (United States)

Berkes, Pietro; Orbán, Gergo; Lengyel, Máté; Fiser, József

2011-01-07

The brain maintains internal models of its environment to interpret sensory inputs and to prepare actions. Although behavioral studies have demonstrated that these internal models are optimally adapted to the statistics of the environment, the neural underpinning of this adaptation is unknown. Using a Bayesian model of sensory cortical processing, we related stimulus-evoked and spontaneous neural activities to inferences and prior expectations in an internal model and predicted that they should match if the model is statistically optimal. To test this prediction, we analyzed visual cortical activity of awake ferrets during development. Similarity between spontaneous and evoked activities increased with age and was specific to responses evoked by natural scenes. This demonstrates the progressive adaptation of internal models to the statistics of natural stimuli at the neural level.

Expression Profiling of Mitogen-Activated Protein Kinase Genes Reveals Their Evolutionary and Functional Diversity in Different Rubber Tree (Hevea brasiliensis Cultivars

Directory of Open Access Journals (Sweden)

Xiang Jin

2017-10-01

Full Text Available Rubber tree (Hevea brasiliensis is the only commercially cultivated plant for producing natural rubber, one of the most essential industrial raw materials. Knowledge of the evolutionary and functional characteristics of kinases in H. brasiliensis is limited because of the long growth period and lack of well annotated genome information. Here, we reported mitogen-activated protein kinases in H. brasiliensis (HbMPKs by manually checking and correcting the rubber tree genome. Of the 20 identified HbMPKs, four members were validated by proteomic data. Protein motif and phylogenetic analyses classified these members into four known groups comprising Thr-Glu-Tyr (TEY and Thr-Asp-Tyr (TDY domains, respectively. Evolutionary and syntenic analyses suggested four duplication events: HbMPK3/HbMPK6, HbMPK8/HbMPK9/HbMPK15, HbMPK10/HbMPK12 and HbMPK11/HbMPK16/HbMPK19. Expression profiling of the identified HbMPKs in roots, stems, leaves and latex obtained from three cultivars with different latex yield ability revealed tissue- and variety-expression specificity of HbMPK paralogues. Gene expression patterns under osmotic, oxidative, salt and cold stresses, combined with cis-element distribution analyses, indicated different regulation patterns of HbMPK paralogues. Further, Ka/Ks and Tajima analyses suggested an accelerated evolutionary rate in paralogues HbMPK10/12. These results revealed HbMPKs have diverse functions in natural rubber biosynthesis, and highlighted the potential possibility of using MPKs to improve stress tolerance in future rubber tree breeding.

Enantiospecific (+)- and (-)-germacrene D synthases, cloned from goldenrod, reveal a functionally active variant of the universal isoprenoid-biosynthesis aspartate-rich motif.

Science.gov (United States)

Prosser, Ian; Altug, Iris G; Phillips, Andy L; König, Wilfried A; Bouwmeester, Harro J; Beale, Michael H

2004-12-15

The naturally occurring, volatile sesquiterpene hydrocarbon germacrene D has strong effects on insect behaviour and genes encoding enzymes that produce this compound are of interest in the study of plant-insect interactions and in a number of biotechnological approaches to pest control. Goldenrod, Solidago canadensis, is unusual in that it produces both enantiomers of germacrene D. Two new sesquiterpene synthase cDNAs, designated Sc11 and Sc19, have been isolated from goldenrod and functional expression in Escherichia coli identified Sc11 as (+)-germacrene D synthase and Sc19 as (-)-germacrene D synthase. Thus, the enantiomers of germacrene D are the products of separate, but closely related (85% amino-acid identity), enzymes. Unlike other sesquiterpene synthases and the related monoterpene synthases and prenyl transferases, which contain the characteristic amino-acid motif DDXX(D,E), Sc11 is unusual in that this motif occurs as (303)NDTYD. Mutagenesis of this motif to (303)DDTYD gave rise to an enzyme that fully retained (+)-germacrene D synthase activity. The converse mutation in Sc19 (D303N) resulted in a less efficient but functional enzyme. Mutagenesis of position 303 to glutamate in both enzymes resulted in loss of activity. These results indicate that the magnesium ion-binding role of the first aspartate in the DDXXD motif may not be as critical as previously thought. Further amino-acid sequence comparisons and molecular modelling of the enzyme structures revealed that very subtle changes to the active site of this family of enzymes are required to alter the reaction pathway to form, in this case, different enantiomers from the same enzyme-bound carbocationic intermediate.

Genetic Correction of SOD1 Mutant iPSCs Reveals ERK and JNK Activated AP1 as a Driver of Neurodegeneration in Amyotrophic Lateral Sclerosis

Directory of Open Access Journals (Sweden)

Akshay Bhinge

2017-04-01

Full Text Available Summary: Although mutations in several genes with diverse functions have been known to cause amyotrophic lateral sclerosis (ALS, it is unknown to what extent causal mutations impinge on common pathways that drive motor neuron (MN-specific neurodegeneration. In this study, we combined induced pluripotent stem cells-based disease modeling with genome engineering and deep RNA sequencing to identify pathways dysregulated by mutant SOD1 in human MNs. Gene expression profiling and pathway analysis followed by pharmacological screening identified activated ERK and JNK signaling as key drivers of neurodegeneration in mutant SOD1 MNs. The AP1 complex member JUN, an ERK/JNK downstream target, was observed to be highly expressed in MNs compared with non-MNs, providing a mechanistic insight into the specific degeneration of MNs. Importantly, investigations of mutant FUS MNs identified activated p38 and ERK, indicating that network perturbations induced by ALS-causing mutations converge partly on a few specific pathways that are drug responsive and provide immense therapeutic potential. : In this article, Bhinge, Stanton, and colleagues use genome editing of patient-derived iPSCs to model ALS phenotypic defects in vitro. Transcriptomic analysis of disease MNs reveals activation of MAPK, AP1, WNT, cell-cycle, and p53 signaling in ALS MNs. Pharmacological screening uncovers activated ERK and JNK signaling as therapeutic targets in ALS. Keywords: ALS, SOD1, FUS, CRISPR-Cas9, p38, ERK, JNK, WNT, TP53, JUN

An Angiotensin II type 1 receptor activation switch patch revealed through Evolutionary Trace analysis

DEFF Research Database (Denmark)

Bonde, Marie Mi; Yao, Rong; Ma, Jian-Nong

2010-01-01

to be completely resolved. Evolutionary Trace (ET) analysis is a computational method, which identifies clusters of functionally important residues by integrating information on evolutionary important residue variations with receptor structure. Combined with known mutational data, ET predicted a patch of residues......) displayed phenotypes associated with changed activation state, such as increased agonist affinity or basal activity, promiscuous activation, or constitutive internalization highlighting the importance of testing different signaling pathways. We conclude that this evolutionary important patch mediates...

Ceres Revealed in a Grain of Salt

Science.gov (United States)

Zolensky, M. E.; Bodnar, R. J.; Fries, M.; Chan, Q. H.-S.; Kebukawa, Y.; Mikouchi, T.; Hagiya, K.; Komatsu, M.; Ohsumi, K.; Steele, A.

2016-01-01

Introduction: Zag and Monahans (1998) are H chondrite regolith breccias containing 4.5 giga-year-old halite crystals which contain abundant inclusions of aqueous fluids, solids and organics. These all originated on a cryo-volcanically-active C class asteroid, probably 1 Ceres; the halite was transported to the regolith of the H chondrite parent asteroid, potentially 6 Hebe. Detailed analysis of these solids will thus potentially reveal the mineralogy of Ceres. Mineralogy of solids in the Monahans Halite Solid grains are present in the halites, which were entrained within the mother brines during eruption, including material from the interior and surface of the erupting body. The solids include abundant, widely variable organics that could not have been significantly heated (which would have resulted in the loss of fluids from the halite). Our analyses by Raman microprobe, SEM/EDX, synchrotron X-ray diffraction, UPLC-FD/QToF-MS, C-XANES and TEM reveal that these trapped grains include macromolecular carbon (MMC) similar in structure to CV3 chondrite matrix carbon, aliphatic carbon compounds, olivine (Fo99-59), high- and low-Ca pyroxene, feldspars, phyllosilicates, magnetite, sulfides, metal, lepidocrocite, carbonates, diamond, apatite and zeolites. Conclusions: The halite in Monahans and Zag derive from a water and carbon-rich object that was cryo-volcanically active in the early solar system, probably Ceres. The Dawn spacecraft found that Ceres includes C chondrite materials. Our samples include both protolith and aqueously-altered samples of the body, permitting understanding of alteration conditions. Whatever the halite parent body, it was rich in a wide variety of organics and warm, liquid water at the solar system's dawn.

Genetic activation, inactivation and deletion reveal a limited and nuanced role for somatostatin-containing basal forebrain neurons in behavioral state control.

Science.gov (United States)

Anaclet, Christelle; De Luca, Roberto; Venner, Anne; Malyshevskaya, Olga; Lazarus, Michael; Arrigoni, Elda; Fuller, Patrick M

2018-05-07

Recent studies have identified an especially important role for basal forebrain GABAergic (BF VGAT ) neurons in the regulation of behavioral waking and fast cortical rhythms associated with cognition. However, BF VGAT neurons comprise several neurochemically and anatomically distinct sub-populations, including parvalbumin- and somatostatin-containing BF VGAT neurons (BF Parv and BF SOM ), and it was recently reported that optogenetic activation of BF SOM neurons increases the probability of a wakefulness to non-rapid-eye movement (NREM) sleep transition when stimulated during the animal's rest period. This finding was unexpected given that most BF SOM neurons are not NREM sleep active and that central administration of the synthetic SOM analog, octreotide, suppresses NREM sleep or increases REM sleep. Here we employed a combination of genetically-driven chemogenetic and optogenetic activation, chemogenetic inhibition and ablation approaches to further explore the in vivo role of BF SOM neurons in arousal control. Our findings indicate that acute activation or inhibition of BF SOM neurons is neither wakefulness- nor NREM sleep-promoting, is without significant effect on the EEG, and that chronic loss of these neurons is without effect on total 24h sleep amounts, although a small but significant increase in waking was observed in the lesioned mice during the early active period. Our in vitro cell recordings further reveal electrophysiological heterogeneity in BF SOM neurons, specifically suggesting at least two distinct sub-populations. Taken together our data support the more nuanced view that BF SOM are electrically heterogeneous and are not NREM sleep- or wake-promoting per se , but may exert, in particular during the early active period, a modest inhibitory influence on arousal circuitry. SIGNIFICANCE STATEMENT The cellular basal forebrain (BF) is a highly complex area of the brain that is implicated in a wide-range of higher-level neurobiological processes

Fingerprint signatures based on nanomagnets as markers in materials for tracing and counterfeit protection

International Nuclear Information System (INIS)

Szielasko, Klaus; Youssef, Amir; Sporn, Dieter; Mandel, Karl

2016-01-01

Identification and tracing of objects is a challenge of great current importance. Ideally, this can be achieved via small markers, which equip an object with a fingerprint identity. Herein, we communicate an approach that is based on structural arrangements of magnetic nano-entities to generate a kind of security key in an object. The nano-markers, which are applied as inks, can remotely be read out in a fast and simple way with a GMR sensor and yield an unmistakable signal pattern.Graphical abstract

Fingerprint signatures based on nanomagnets as markers in materials for tracing and counterfeit protection

Energy Technology Data Exchange (ETDEWEB)

Szielasko, Klaus; Youssef, Amir [Fraunhofer Institute for Nondestructive Testing IZFP (Germany); Sporn, Dieter; Mandel, Karl, E-mail: karl-sebastian.mandel@isc.fraunhofer.de [Fraunhofer Institute for Silicate Research ISC (Germany)

2016-05-15

Identification and tracing of objects is a challenge of great current importance. Ideally, this can be achieved via small markers, which equip an object with a fingerprint identity. Herein, we communicate an approach that is based on structural arrangements of magnetic nano-entities to generate a kind of security key in an object. The nano-markers, which are applied as inks, can remotely be read out in a fast and simple way with a GMR sensor and yield an unmistakable signal pattern.Graphical abstract.

A bar-code reader for an alpha-beta automatic counting system - FAG

Energy Technology Data Exchange (ETDEWEB)

Levinson, S; Shemesh, Y; Ankry, N; Assido, H; German, U; Peled, O [Israel Atomic Energy Commission, Beersheba (Israel). Nuclear Research Center-Negev

1996-12-01

A bar-code laser system for sample number reading was integrated into the FAG Alpha-Beta automatic counting system. The sample identification by means of an attached bar-code label enables unmistakable and reliable attribution of results to the counted sample. Installation of the bar-code reader system required several modifications: Mechanical changes in the automatic sample changer, design and production of new sample holders, modification of the sample planchettes, changes in the electronic system, update of the operating software of the system (authors).

A bar-code reader for an alpha-beta automatic counting system - FAG

International Nuclear Information System (INIS)

Levinson, S.; Shemesh, Y.; Ankry, N.; Assido, H.; German, U.; Peled, O.

1996-01-01

A bar-code laser system for sample number reading was integrated into the FAG Alpha-Beta automatic counting system. The sample identification by means of an attached bar-code label enables unmistakable and reliable attribution of results to the counted sample. Installation of the bar-code reader system required several modifications: Mechanical changes in the automatic sample changer, design and production of new sample holders, modification of the sample planchettes, changes in the electronic system, update of the operating software of the system (authors)

KLIMT, FROM PAINTING TO FASHION

OpenAIRE

URDEA Olimpia

2015-01-01

Fashion has been a subject for most fields of art, starting from visual arts to cinema and literature. The metamorphoses of fashion, an art in itself, are under the sign of history that marked the social during the evolution of humanity. The present paper makes a reference to the links between fashion and Klimt’s work. Klimt proved to be a visionary by means of his visual, unique and unmistakable signature concerning the way he treated the clothed woman. As he worshipped the female body, he ...

Fluid escape structures in the Graham Bank region (Sicily Channel, Central Mediterranean) revealing volcanic and neotectonic activity.

Science.gov (United States)

Spatola, Daniele; Pennino, Valentina; Basilone, Luca; Interbartolo, Francesco; Micallef, Aaron; Sulli, Attilio; Basilone, Walter

2016-04-01

morphometric analysis of these volcanoes has been conducted: they are up to about 115-160 m high and 500-1500 m wide. Most of them show very strongly inclined flanks with 30° of average slope. The SCV2 and SCV3 form the Graham Bank, 3.5X2.8 km wide, elongated in the NW-SE direction. At the top of SCV2 focused seepage plumes were observed in the entire water column, through the CHIRP data, where we calculated that they release, a volume of about 10950 m3 and 43960 m3of gases, respectively. In this work, we present the first results of a data collection that have got as main result the identification and mapping of the fluid escape structures revealing the relationship between the active tectonic with migration of fluids, to be used to assess the Submarine Geo-Hazard in the Sicily Channel. We identified two fluid escape fields whose genesis and evolution appear linked to the neotectonic and volcanic activities respectively, that represent the main controlling factors for the migration of fluid; considering the good correlation between pockmarks and the main identified fault systems. In conclusion, our results suggest that the degassing of fluids in this region is rooted at depth, and is mainly aligned with the NW-SE dip/strike slip fault systems, repeatedly reactivated, and linked to the volcanic activity.

Assessment of synergistic antibacterial activity of combined biosurfactants revealed by bacterial cell envelop damage.

Science.gov (United States)

Sana, Santanu; Datta, Sriparna; Biswas, Dipa; Sengupta, Dipanjan

2018-02-01

Besides potential surface activity and some beneficial physical properties, biosurfactants express antibacterial activity. Bacterial cell membrane disrupting ability of rhamnolipid produced by Pseudomonas aeruginosa C2 and a lipopeptide type biosurfactant, BS15 produced by Bacillus stratosphericus A15 was examined against Staphylococcus aureus ATCC 25923 and Escherichia coli K8813. Broth dilution technique was followed to examine minimum inhibitory concentration (MIC) of both the biosurfactants. The combined effect of rhamnolipid and BS15 against S. aureus and E. coli showed synergistic activity by expressing fractional inhibitory concentration (FIC) index of 0.43 and 0.5. Survival curve of both the bacteria showed bactericidal activity after treating with biosurfactants at their MIC obtained from FIC index study as it killed >90% of initial population. The lesser value of MIC than minimum bactericidal concentration (MBC) of the biosurfactants also supported their bactericidal activity against both the bacteria. Membrane permeability against both the bacteria was supported by amplifying protein release, increasing of cell surface hydrophobicity, withholding capacity of crystal violet dye and leakage of intracellular materials. Finally cell membrane disruption was confirmed by scanning electron microscopy (SEM). All these experiments expressed synergism and effective bactericidal activity of the combination of rhamnolipid and BS15 by enhancing the bacterial cell membrane permeability. Such effect of the combination of rhamnolipid and BS15 could make them promising alternatives to traditional antibiotic in near future. Copyright © 2017 Elsevier B.V. All rights reserved.

Structures of apicomplexan calcium-dependent protein kinases reveal mechanism of activation by calcium

Energy Technology Data Exchange (ETDEWEB)

Wernimont, Amy K; Artz, Jennifer D.; Jr, Patrick Finerty; Lin, Yu-Hui; Amani, Mehrnaz; Allali-Hassani, Abdellah; Senisterra, Guillermo; Vedadi, Masoud; Tempel, Wolfram; Mackenzie, Farrell; Chau, Irene; Lourido, Sebastian; Sibley, L. David; Hui, Raymond (Toronto); (WU-MED)

2010-09-21

Calcium-dependent protein kinases (CDPKs) have pivotal roles in the calcium-signaling pathway in plants, ciliates and apicomplexan parasites and comprise a calmodulin-dependent kinase (CaMK)-like kinase domain regulated by a calcium-binding domain in the C terminus. To understand this intramolecular mechanism of activation, we solved the structures of the autoinhibited (apo) and activated (calcium-bound) conformations of CDPKs from the apicomplexan parasites Toxoplasma gondii and Cryptosporidium parvum. In the apo form, the C-terminal CDPK activation domain (CAD) resembles a calmodulin protein with an unexpected long helix in the N terminus that inhibits the kinase domain in the same manner as CaMKII. Calcium binding triggers the reorganization of the CAD into a highly intricate fold, leading to its relocation around the base of the kinase domain to a site remote from the substrate binding site. This large conformational change constitutes a distinct mechanism in calcium signal-transduction pathways.

The early asthmatic response is associated with glycolysis, calcium binding and mitochondria activity as revealed by proteomic analysis in rats

Directory of Open Access Journals (Sweden)

Xu Yu-Dong

2010-08-01

Full Text Available Abstract Background The inhalation of allergens by allergic asthmatics results in the early asthmatic response (EAR, which is characterized by acute airway obstruction beginning within a few minutes. The EAR is the earliest indicator of the pathological progression of allergic asthma. Because the molecular mechanism underlying the EAR is not fully defined, this study will contribute to a better understanding of asthma. Methods In order to gain insight into the molecular basis of the EAR, we examined changes in protein expression patterns in the lung tissue of asthmatic rats during the EAR using 2-DE/MS-based proteomic techniques. Bioinformatic analysis of the proteomic data was then performed using PPI Spider and KEGG Spider to investigate the underlying molecular mechanism. Results In total, 44 differentially expressed protein spots were detected in the 2-DE gels. Of these 44 protein spots, 42 corresponded to 36 unique proteins successfully identified using mass spectrometry. During subsequent bioinformatic analysis, the gene ontology classification, the protein-protein interaction networking and the biological pathway exploration demonstrated that the identified proteins were mainly involved in glycolysis, calcium binding and mitochondrial activity. Using western blot and semi-quantitative RT-PCR, we confirmed the changes in expression of five selected proteins, which further supports our proteomic and bioinformatic analyses. Conclusions Our results reveal that the allergen-induced EAR in asthmatic rats is associated with glycolysis, calcium binding and mitochondrial activity, which could establish a functional network in which calcium binding may play a central role in promoting the progression of asthma.

Large-scale transcriptome data reveals transcriptional activity of fission yeast LTR retrotransposons

DEFF Research Database (Denmark)

Mourier, Tobias; Willerslev, Eske

2010-01-01

of transcriptional activity are observed from both strands of solitary LTR sequences. Transcriptome data collected during meiosis suggests that transcription of solitary LTRs is correlated with the transcription of nearby protein-coding genes. CONCLUSIONS: Presumably, the host organism negatively regulates...

Cancer gene profiling in non-small cell lung cancers reveals activating mutations in JAK2 and JAK3 with therapeutic implications

Directory of Open Access Journals (Sweden)

Shuyu D. Li

2017-10-01

Full Text Available Abstract Background Next-generation sequencing (NGS of cancer gene panels are widely applied to enable personalized cancer therapy and to identify novel oncogenic mutations. Methods We performed targeted NGS on 932 clinical cases of non-small-cell lung cancers (NSCLCs using the Ion AmpliSeq™ Cancer Hotspot panel v2 assay. Results Actionable mutations were identified in 65% of the cases with available targeted therapeutic options, including 26% of the patients with mutations in National Comprehensive Cancer Network (NCCN guideline genes. Most notably, we discovered JAK2 p.V617F somatic mutation, a hallmark of myeloproliferative neoplasms, in 1% (9/932 of the NSCLCs. Analysis of cancer cell line pharmacogenomic data showed that a high level of JAK2 expression in a panel of NSCLC cell lines is correlated with increased sensitivity to a selective JAK2 inhibitor. Further analysis of TCGA genomic data revealed JAK2 gain or loss due to genetic alterations in NSCLC clinical samples are associated with significantly elevated or reduced PD-L1 expression, suggesting that the activating JAK2 p.V617F mutation could confer sensitivity to both JAK inhibitors and anti-PD1 immunotherapy. We also detected JAK3 germline activating mutations in 6.7% (62/932 of the patients who may benefit from anti-PD1 treatment, in light of recent findings that JAK3 mutations upregulate PD-L1 expression. Conclusion Taken together, this study demonstrated the clinical utility of targeted NGS with a focused hotspot cancer gene panel in NSCLCs and identified activating mutations in JAK2 and JAK3 with clinical implications inferred through integrative analysis of cancer genetic, genomic, and pharmacogenomic data. The potential of JAK2 and JAK3 mutations as response markers for the targeted therapy against JAK kinases or anti-PD1 immunotherapy warrants further investigation.

Multichannel brain recordings in behaving Drosophila reveal oscillatory activity and local coherence in response to sensory stimulation and circuit activation

Science.gov (United States)

Paulk, Angelique C.; Zhou, Yanqiong; Stratton, Peter; Liu, Li

2013-01-01

Neural networks in vertebrates exhibit endogenous oscillations that have been associated with functions ranging from sensory processing to locomotion. It remains unclear whether oscillations may play a similar role in the insect brain. We describe a novel “whole brain” readout for Drosophila melanogaster using a simple multichannel recording preparation to study electrical activity across the brain of flies exposed to different sensory stimuli. We recorded local field potential (LFP) activity from >2,000 registered recording sites across the fly brain in >200 wild-type and transgenic animals to uncover specific LFP frequency bands that correlate with: 1) brain region; 2) sensory modality (olfactory, visual, or mechanosensory); and 3) activity in specific neural circuits. We found endogenous and stimulus-specific oscillations throughout the fly brain. Central (higher-order) brain regions exhibited sensory modality-specific increases in power within narrow frequency bands. Conversely, in sensory brain regions such as the optic or antennal lobes, LFP coherence, rather than power, best defined sensory responses across modalities. By transiently activating specific circuits via expression of TrpA1, we found that several circuits in the fly brain modulate LFP power and coherence across brain regions and frequency domains. However, activation of a neuromodulatory octopaminergic circuit specifically increased neuronal coherence in the optic lobes during visual stimulation while decreasing coherence in central brain regions. Our multichannel recording and brain registration approach provides an effective way to track activity simultaneously across the fly brain in vivo, allowing investigation of functional roles for oscillations in processing sensory stimuli and modulating behavior. PMID:23864378

Multichannel brain recordings in behaving Drosophila reveal oscillatory activity and local coherence in response to sensory stimulation and circuit activation.

Science.gov (United States)

Paulk, Angelique C; Zhou, Yanqiong; Stratton, Peter; Liu, Li; van Swinderen, Bruno

2013-10-01

Neural networks in vertebrates exhibit endogenous oscillations that have been associated with functions ranging from sensory processing to locomotion. It remains unclear whether oscillations may play a similar role in the insect brain. We describe a novel "whole brain" readout for Drosophila melanogaster using a simple multichannel recording preparation to study electrical activity across the brain of flies exposed to different sensory stimuli. We recorded local field potential (LFP) activity from >2,000 registered recording sites across the fly brain in >200 wild-type and transgenic animals to uncover specific LFP frequency bands that correlate with: 1) brain region; 2) sensory modality (olfactory, visual, or mechanosensory); and 3) activity in specific neural circuits. We found endogenous and stimulus-specific oscillations throughout the fly brain. Central (higher-order) brain regions exhibited sensory modality-specific increases in power within narrow frequency bands. Conversely, in sensory brain regions such as the optic or antennal lobes, LFP coherence, rather than power, best defined sensory responses across modalities. By transiently activating specific circuits via expression of TrpA1, we found that several circuits in the fly brain modulate LFP power and coherence across brain regions and frequency domains. However, activation of a neuromodulatory octopaminergic circuit specifically increased neuronal coherence in the optic lobes during visual stimulation while decreasing coherence in central brain regions. Our multichannel recording and brain registration approach provides an effective way to track activity simultaneously across the fly brain in vivo, allowing investigation of functional roles for oscillations in processing sensory stimuli and modulating behavior.

Geolocation Reveals Year-Round at-Sea Distribution and Activity of a Superabundant Tropical Seabird, the Sooty Tern Onychoprion fuscatus

Directory of Open Access Journals (Sweden)

Audrey Jaeger

2017-12-01

Full Text Available Migration is a fundamental aspect of the ecology and evolutionary history of many animals, driven by seasonal changes in resource availability and habitat structure. Seabird migration has been investigated extensively in highly seasonal temperate and polar environments. By contrast, the relationships between migration and seasonal environmental changes have rarely been studied in tropical marine habitats. The sooty tern Onychoprion fuscatus is the most abundant tropical seabirds, and has been ranked as the most important tropical species in terms of its annual estimated consumption of marine resources. We used global location sensing (GLS loggers to describe for the first time the year-round at-sea distribution and activity patterns of sooty terns from a large breeding colony in the western Indian Ocean (Bird Island, Seychelles. While breeding, they foraged within 1,074 ± 274 km of the colony. After breeding, birds undertook an extensive post-breeding migration throughout the Indian Ocean; average distances traveled exceeded 50,000 km per individual. Sooty terns used mainly four distinct core oceanic areas during the non-breeding period; in the Bay of Bengal (A, northeast to an area straddling the Chagos-Laccadive plateau (B, southeast to an area on each side of the 90 East Ridge (C and southwest to an area around Comoros (D. Individuals exhibited a high degree of fidelity to these core areas in successive years. We also established that they performed an unusual behavior for a non-Procellariiformes seabird; most individuals undertook a 1-month pre-laying exodus, during which they foraged in a specific area c. 2,000 km to the south-east of the colony. Year-round at-sea activity of sooty terns revealed that they spent only 3.72% of their time in contact with seawater, so indicating that they must sleep in flight. Activity parameters exhibited seasonal (breeding vs. non-breeding periods and daily variations; they notably never land on the water

Protein expression profiling of inflammatory mediators in human temporal lobe epilepsy reveals co-activation of multiple chemokines and cytokines

Directory of Open Access Journals (Sweden)

Kan Anne A

2012-08-01

Full Text Available Abstract Mesial temporal lobe epilepsy (mTLE is a chronic and often treatment-refractory brain disorder characterized by recurrent seizures originating from the hippocampus. The pathogenic mechanisms underlying mTLE remain largely unknown. Recent clinical and experimental evidence supports a role of various inflammatory mediators in mTLE. Here, we performed protein expression profiling of 40 inflammatory mediators in surgical resection material from mTLE patients with and without hippocampal sclerosis, and autopsy controls using a multiplex bead-based immunoassay. In mTLE patients we identified 21 upregulated inflammatory mediators, including 10 cytokines and 7 chemokines. Many of these upregulated mediators have not previously been implicated in mTLE (for example, CCL22, IL-7 and IL-25. Comparing the three patient groups, two main hippocampal expression patterns could be distinguished, pattern I (for example, IL-10 and IL-25 showing increased expression in mTLE + HS patients compared to mTLE-HS and controls, and pattern II (for example, CCL4 and IL-7 showing increased expression in both mTLE groups compared to controls. Upregulation of a subset of inflammatory mediators (for example, IL-25 and IL-7 could not only be detected in the hippocampus of mTLE patients, but also in the neocortex. Principle component analysis was used to cluster the inflammatory mediators into several components. Follow-up analyses of the identified components revealed that the three patient groups could be discriminated based on their unique expression profiles. Immunocytochemistry showed that IL-25 IR (pattern I and CCL4 IR (pattern II were localized in astrocytes and microglia, whereas IL-25 IR was also detected in neurons. Our data shows co-activation of multiple inflammatory mediators in hippocampus and neocortex of mTLE patients, indicating activation of multiple pro- and anti-epileptogenic immune pathways in this disease.

Molecular and Silica-Supported Molybdenum Alkyne Metathesis Catalysts: Influence of Electronics and Dynamics on Activity Revealed by Kinetics, Solid-State NMR, and Chemical Shift Analysis.

Science.gov (United States)

Estes, Deven P; Gordon, Christopher P; Fedorov, Alexey; Liao, Wei-Chih; Ehrhorn, Henrike; Bittner, Celine; Zier, Manuel Luca; Bockfeld, Dirk; Chan, Ka Wing; Eisenstein, Odile; Raynaud, Christophe; Tamm, Matthias; Copéret, Christophe

2017-12-06

Molybdenum-based molecular alkylidyne complexes of the type [MesC≡Mo{OC(CH 3 ) 3-x (CF 3 ) x } 3 ] (MoF 0 , x = 0; MoF 3 , x = 1; MoF 6 , x = 2; MoF 9 , x = 3; Mes = 2,4,6-trimethylphenyl) and their silica-supported analogues are prepared and characterized at the molecular level, in particular by solid-state NMR, and their alkyne metathesis catalytic activity is evaluated. The 13 C NMR chemical shift of the alkylidyne carbon increases with increasing number of fluorine atoms on the alkoxide ligands for both molecular and supported catalysts but with more shielded values for the supported complexes. The activity of these catalysts increases in the order MoF 0 molecular and supported species. Detailed solid-state NMR analysis of molecular and silica-supported metal alkylidyne catalysts coupled with DFT/ZORA calculations rationalize the NMR spectroscopic signatures and discernible activity trends at the frontier orbital level: (1) increasing the number of fluorine atoms lowers the energy of the π*(M≡C) orbital, explaining the more deshielded chemical shift values; it also leads to an increased electrophilicity and higher reactivity for catalysts up to MoF 6 , prior to a sharp decrease in reactivity for MoF 9 due to the formation of stable metallacyclobutadiene intermediates; (2) the silica-supported catalysts are less active than their molecular analogues because they are less electrophilic and dynamic, as revealed by their 13 C NMR chemical shift tensors.

Vascular Targeting in Pancreatic Cancer: The Novel Tubulin-Binding Agent ZD6126 Reveals Antitumor Activity in Primary and Metastatic Tumor Models

Directory of Open Access Journals (Sweden)

Axel Kleespies

2005-10-01

Full Text Available ZD6126 is a novel vascular-targeting agent that acts by disrupting the tubulin cytoskeleton of an immature tumor endothelium, leading to an occlusion of tumor blood vessels and a subsequent tumor necrosis. We wanted to evaluate ZD6126 in primary and metastatic tumor models of human pancreatic cancer. Nude mice were injected orthotopically with L3.6pl pancreatic cancer cells. In single and multiple dosing experiments, mice received ZD6126, gemcitabine, a combination of both agents, or no treatment. For the induction of metastatic disease, additional groups of mice were injected with L3.6pl cells into the spleen. Twenty-four hours after a single-dose treatment, ZD6126 therapy led to an extensive central tumor necrosis, which was not seen after gemcitabine treatment. Multiple dosing of ZD6126 resulted in a significant growth inhibition of primary tumors and a marked reduction of spontaneous liver and lymph node metastases. Experimental metastatic disease could be significantly controlled by a combination of ZD6126 and gemcitabine, as shown by a reduction of the number and size of established liver metastases. As shown by additional in vitro and in vivo experiments, possible mechanisms involve antivascular activities and subsequent antiproliferative and proapoptotic effects of ZD6126 on tumor cells, whereas direct activities against tumor cells seem unlikely. These data highlight the antitumor and antimetastatic effects of ZD6126 in human pancreatic cancer and reveal benefits of adding ZD6126 to standard gemcitabine therapy.

Time-Varying Networks of Inter-Ictal Discharging Reveal Epileptogenic Zone.

Science.gov (United States)

Zhang, Luyan; Liang, Yi; Li, Fali; Sun, Hongbin; Peng, Wenjing; Du, Peishan; Si, Yajing; Song, Limeng; Yu, Liang; Xu, Peng

2017-01-01

The neuronal synchronous discharging may cause an epileptic seizure. Currently, most of the studies conducted to investigate the mechanism of epilepsy are based on EEGs or functional magnetic resonance imaging (fMRI) recorded during the ictal discharging or the resting-state, and few studies have probed into the dynamic patterns during the inter-ictal discharging that are much easier to record in clinical applications. Here, we propose a time-varying network analysis based on adaptive directed transfer function to uncover the dynamic brain network patterns during the inter-ictal discharging. In addition, an algorithm based on the time-varying outflow of information derived from the network analysis is developed to detect the epileptogenic zone. The analysis performed revealed the time-varying network patterns during different stages of inter-ictal discharging; the epileptogenic zone was activated prior to the discharge onset then worked as the source to propagate the activity to other brain regions. Consistence between the epileptogenic zones detected by our proposed approach and the actual epileptogenic zones proved that time-varying network analysis could not only reveal the underlying neural mechanism of epilepsy, but also function as a useful tool in detecting the epileptogenic zone based on the EEGs in the inter-ictal discharging.

Perturbation of whole-brain dynamics in silico reveals mechanistic differences between brain states

NARCIS (Netherlands)

Deco, Gustavo; Cabral, Joana; Saenger, Victor M; Boly, Melanie; Tagliazucchi, Enzo; Laufs, Helmut; Van Someren, Eus; Jobst, Beatrice; Stevner, Angus; Kringelbach, Morten L

2017-01-01

Human neuroimaging research has revealed that wakefulness and sleep involve very different activity patterns. Yet, it is not clear why brain states differ in their dynamical complexity, e.g. in the level of integration and segregation across brain networks over time. Here, we investigate the

Perturbation of whole-brain dynamics in silico reveals mechanistic differences between brain states

NARCIS (Netherlands)

Deco, Gustavo; Cabral, Joana; Saenger, Victor M; Boly, Melanie; Tagliazucchi, Enzo; Laufs, Helmut; Van Someren, Eus; Jobst, Beatrice M; Stevner, Angus B A; Kringelbach, Morten L

2018-01-01

Human neuroimaging research has revealed that wakefulness and sleep involve very different activity patterns. Yet, it is not clear why brain states differ in their dynamical complexity, e.g. in the level of integration and segregation across brain networks over time. Here, we investigate the

Near-infrared spectroscopy can reveal increases in brain activity related to animal-assisted therapy.

Science.gov (United States)

Morita, Yuka; Ebara, Fumio; Morita, Yoshimitsu; Horikawa, Etsuo

2017-08-01

[Purpose] Previous studies have indicated that animal-assisted therapy can promote recovery of psychological, social, and physiological function in mental disorders. This study was designed as a pilot evaluation of the use of near-infrared spectroscopy to objectively identify changes in brain activity that could mediate the effect of animal-assisted therapy. [Subjects and Methods] The participants were 20 healthy students (10 males and 10 females; age 19-21 years) of the Faculty of Agriculture, Saga University. Participants were shown a picture of a Tokara goat or shack (control) while prefrontal cortical oxygenated haemoglobin levels (representing neural activity) were measured by near-infrared spectroscopy. [Results] The prefrontal cortical near-infrared spectroscopy signal was significantly higher during viewing of the animal picture than during a rest condition or during viewing of the control picture. [Conclusion] Our results suggest that near-infrared spectroscopy can be used to objectively identify brain activity changes during human mentation regarding animals; furthermore, these preliminary results suggest the efficacy of animal-assisted therapy could be related to increased activation of the prefrontal cortex.

Taste, terroir, and technology

Directory of Open Access Journals (Sweden)

Pinder RM

2016-03-01

Full Text Available Roger M PinderInternational Journal of Wine Research, York, UKWine drinkers have long acknowledged the link between taste and terroir, the often unmistakable connection between the flavor of a wine and the particular patch of ground in which the vines were grown. But the science behind the connection, indeed the whole concept of taste and terroir, has long been disputed. New technological developments in both "neuroenology" – how the brain creates the taste of wine1 – and in wine chemistry2 have offered more insight into the science.

X-ray changes of children with chronic renal insufficiency

Energy Technology Data Exchange (ETDEWEB)

Ponhold, W.; Balzar, E. (Vienna Univ. (Austria). Kinderklinik)

1983-01-01

The typical changes of renal osteopathy are shown in the X-rays of 7 children with end-stage renal disease treated with chronic intermittent hemodialysis. The exact evaluation of the granular structural changes of the cranium, the evidence of osteomalacia because of the hazy appearance of the vertebrae and the broadening of the sacroilical joints depend highly on subjective judgement and the technical X-ray procedures used. Unmistakable radiological diagnoses can be made when a broadening of the metalphyseal zones, epiphysioloysis as well as characteristic changes in the finder phalanges (acroosteolyses, spiculae, tunnelation) are present.

IDENTIFICATION AND ECOPHYSIOLOGY OF ACTIVE DENITRIFIERS IN ACTIVATED SLUDGE

DEFF Research Database (Denmark)

Hansen, Aviaja Anna; Le-Quy, Vang; Nielsen, Kåre Lehmann

reactor studies. To obtain better identification of active denitrifying communities in full-scale wastewater treatment plants (WWTPs) we applied DNA-SIP with 13C-labelled substrates, and RT-PCR of expressed denitrification genes (nirS, nirK and nosZ) upon various substrate-inductions. To come around...... were determined with quantitative FISH, while their active metabolic pathways were investigated directly in activated sludge with a tag-based metatranscriptomic approach under acetate-utilizing and denitrifying conditions. The different methods revealed a majority of denitrifiers in all WWTPs belonging...

Alterations in task-induced activity and resting-state fluctuations in visual and DMN areas revealed in long-term meditators.

Science.gov (United States)

Berkovich-Ohana, Aviva; Harel, Michal; Hahamy, Avital; Arieli, Amos; Malach, Rafael

2016-07-15

Recently we proposed that the information contained in spontaneously emerging (resting-state) fluctuations may reflect individually unique neuro-cognitive traits. One prediction of this conjecture, termed the "spontaneous trait reactivation" (STR) hypothesis, is that resting-state activity patterns could be diagnostic of unique personalities, talents and life-styles of individuals. Long-term meditators could provide a unique experimental group to test this hypothesis. Using fMRI we found that, during resting-state, the amplitude of spontaneous fluctuations in long-term mindfulness meditation (MM) practitioners was enhanced in the visual cortex and significantly reduced in the DMN compared to naïve controls. Importantly, during a visual recognition memory task, the MM group showed heightened visual cortex responsivity, concomitant with weaker negative responses in Default Mode Network (DMN) areas. This effect was also reflected in the behavioral performance, where MM practitioners performed significantly faster than the control group. Thus, our results uncover opposite changes in the visual and default mode systems in long-term meditators which are revealed during both rest and task. The results support the STR hypothesis and extend it to the domain of local changes in the magnitude of the spontaneous fluctuations. Copyright © 2016 Elsevier Inc. All rights reserved.

Creatine-induced activation of antioxidative defence in myotube cultures revealed by explorative NMR-based metabonomics and proteomics

DEFF Research Database (Denmark)

Young, Jette Feveile; Larsen, Lotte Bach; Malmendal, Anders

2010-01-01

Creatine is a key intermediate in energy metabolism and supplementation of creatine has been used for increasing muscle mass, strength and endurance. Creatine supplementation has also been reported to trigger the skeletal muscle expression of insulin like growth factor I, to increase the fat......-free mass and improve cognition in elderly, and more explorative approaches like transcriptomics has revealed additional information. The aim of the present study was to reveal additional insight into the biochemical effects of creatine supplementation at the protein and metabolite level by integrating...... the explorative techniques, proteomics and NMR metabonomics, in a systems biology approach. METHODS: Differentiated mouse myotube cultures (C2C12) were exposed to 5 mM creatine monohydrate (CMH) for 24 hours. For proteomics studies, lysed myotubes were analyzed in single 2-DGE gels where the first dimension...

Single Turnover at Molecular Polymerization Catalysts Reveals Spatiotemporally Resolved Reactions.

Science.gov (United States)

Easter, Quinn T; Blum, Suzanne A

2017-10-23

Multiple active individual molecular ruthenium catalysts have been pinpointed within growing polynorbornene, thereby revealing information on the reaction dynamics and location that is unavailable through traditional ensemble experiments. This is the first single-turnover imaging of a molecular catalyst by fluorescence microscopy and allows detection of individual monomer reactions at an industrially important molecular ruthenium ring-opening metathesis polymerization (ROMP) catalyst under synthetically relevant conditions (e.g. unmodified industrial catalyst, ambient pressure, condensed phase, ca. 0.03 m monomer). These results further establish the key fundamentals of this imaging technique for characterizing the reactivity and location of active molecular catalysts even when they are the minor components. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Field trip method as an effort to reveal student environmental literacy on biodiversity issue and context

Science.gov (United States)

Rijal, M.; Saefudin; Amprasto

2018-05-01

Field trip method through investigation of local biodiversity cases can give educational experiences for students. This learning activity was efforts to reveal students environmental literacy on biodiversity. The aim of study were (1) to describe the activities of students get information about the biodiversity issue and its context through field trip, (2) to describe the students findings during field trip, and (3) to reveal students environmental literacy based on pre test and post test. The research method used weak-experiment and involved 34 participants at senior high school students in Bandung-Indonesia. The research instruments for collecting data were environmental literacy test, observation sheets and questionnaire sheets for students. The analysis of data was quantitative descriptive. The results show that more than 79% of the students gave positive view for each field trip activity, i.e students activity during work (97%-100%); students activity during gather information (79%- 100%); students activity during exchange information with friend (82%-100%); and students interested to Biodiversity after field trip activity (85%-100%). Students gain knowledge about the diversity of animal vertebrate and its characteristics, the status and condition of animals, and the source of animal with the cases of animal diversity. The students environmental literacy tends to be moderate level based on test. Meanwhile, the average of the attitudes and action greater than the components of knowledge and cognitive skills.

Extensive small-angle X-ray scattering studies of blood coagulation factor VIIa reveal interdomain flexibility

DEFF Research Database (Denmark)

Mosbæk, Charlotte Rode; Nolan, David; Persson, Egon

2010-01-01

Blood coagulation factor VIIa (FVIIa) is used in the treatment of replacement therapy resistant hemophilia patients, and FVIIa is normally activated upon complex formation with tissue factor (TF), potentially in context with structural rearrangements. The solution behavior of uncomplexed FVIIa...... is important for understanding the mechanism of activation and for the stability and activity of the pharmaceutical product. However, crystal structures of FVIIa in complex with TF and of truncated free FVIIa reveal different overall conformations while previous small-angle scattering studies suggest FVIIa...... causing resistance to activation, thereby emphasizing the connection between the distribution of different conformations of FVII and the mechanism of activation....

Gravity and magma induces spreading of Mount Etna volcano revealed by satellite radar interferometry

Science.gov (United States)

Lungren, P.; Casu, F.; Manzo, M.; Pepe, A.; Berardino, P.; Sansosti, E.; Lanari, R.

2004-01-01

Mount Etna underwent a cycle of eruptive activity over the past ten years. Here we compute ground displacement maps and deformation time series from more than 400 radar interferograms to reveal Mount Etna's average and time varying surface deformation from 1992 to 2001.

Structure of TSA2 reveals novel features of the active-site loop of peroxiredoxins

DEFF Research Database (Denmark)

Nielsen, Maja Holch; Kidmose, Rune Thomas; Jenner, Lasse Bohl

2016-01-01

Saccharomyces cerevisiae TSA2 belongs to the family of typical 2-Cys peroxiredoxins, a ubiquitously expressed family of redox-active enzymes that utilize a conserved peroxidatic cysteine to reduce peroxides. Typical 2-Cys peroxiredoxins have been shown to be involved in protection against oxidative...... stress and in hydrogen peroxide signalling. Furthermore, several 2-Cys peroxiredoxins, including S. cerevisiae TSA1 and TSA2, are able to switch to chaperone activity upon hyperoxidation of their peroxidatic cysteine. This makes the sensitivity to hyperoxidation of the peroxidatic cysteine a very....... This requires a local unfolding of the active site and the C-terminus. The balance between the fully folded and locally unfolded conformations is of key importance for the reactivity and sensitivity to hyperoxidation of the different peroxiredoxins. Here, the structure of a C48S mutant of TSA2 from S...

High resolution in situ zymography reveals matrix metalloproteinase activity at glutamatergic synapses.

Science.gov (United States)

Gawlak, M; Górkiewicz, T; Gorlewicz, A; Konopacki, F A; Kaczmarek, L; Wilczynski, G M

2009-01-12

Synaptic plasticity involves remodeling of extracellular matrix. This is mediated, in part, by enzymes of the matrix metalloproteinase (MMP) family, in particular by gelatinase MMP-9. Accordingly, there is a need of developing methods to visualize gelatinolytic activity at the level of individual synapses, especially in the context of neurotransmitters receptors. Here we present a high-resolution fluorescent in situ zymography (ISZ), performed in thin sections of the alcohol-fixed and polyester wax-embedded brain tissue of the rat (Rattus norvegicus), which is superior to the current ISZ protocols. The method allows visualization of structural details up to the resolution-limit of light microscopy, in conjunction with immunofluorescent labeling. We used this technique to visualize and quantify gelatinolytic activity at the synapses in control and seizure-affected rat brain. In particular, we demonstrated, for the first time, frequent colocalization of gelatinase(s) with synaptic N-methyl-D-aspartic acid (NMDA)- and AMPA-type glutamate receptors. We believe that our method represents a valuable tool to study extracellular proteolytic processes at the synapses, it could be used, as well, to investigate proteinase involvement in a range of physiological and pathological phenomena in the nervous system.

Structure of Human GIVD Cytosolic Phospholipase A2 Reveals Insights into Substrate Recognition

Energy Technology Data Exchange (ETDEWEB)

Wang, Hui; Klein, Michael G.; Snell, Gyorgy; Lane, Weston; Zou, Hua; Levin, Irena; Li, Ke; Sang, Bi-Ching (Takeda Cali)

2016-07-01

Cytosolic phospholipases A2 (cPLA2s) consist of a family of calcium-sensitive enzymes that function to generate lipid second messengers through hydrolysis of membrane-associated glycerophospholipids. The GIVD cPLA2 (cPLA2δ) is a potential drug target for developing a selective therapeutic agent for the treatment of psoriasis. Here, we present two X-ray structures of human cPLA2δ, capturing an apo state, and in complex with a substrate-like inhibitor. Comparison of the apo and inhibitor-bound structures reveals conformational changes in a flexible cap that allows the substrate to access the relatively buried active site, providing new insight into the mechanism for substrate recognition. The cPLA2δ structure reveals an unexpected second C2 domain that was previously unrecognized from sequence alignments, placing cPLA2δ into the class of membrane-associated proteins that contain a tandem pair of C2 domains. Furthermore, our structures elucidate novel inter-domain interactions and define three potential calcium-binding sites that are likely important for regulation and activation of enzymatic activity. These findings provide novel insights into the molecular mechanisms governing cPLA2's function in signal transduction.

Targeted massively parallel sequencing of angiosarcomas reveals frequent activation of the mitogen activated protein kinase pathway

Science.gov (United States)

Murali, Rajmohan; Chandramohan, Raghu; Möller, Inga; Scholz, Simone L.; Berger, Michael; Huberman, Kety; Viale, Agnes; Pirun, Mono; Socci, Nicholas D.; Bouvier, Nancy; Bauer, Sebastian; Artl, Monika; Schilling, Bastian; Schimming, Tobias; Sucker, Antje; Schwindenhammer, Benjamin; Grabellus, Florian; Speicher, Michael R.; Schaller, Jörg; Hillen, Uwe; Schadendorf, Dirk; Mentzel, Thomas; Cheng, Donavan T.; Wiesner, Thomas; Griewank, Klaus G.

2015-01-01

Angiosarcomas are rare malignant mesenchymal tumors of endothelial differentiation. The clinical behavior is usually aggressive and the prognosis for patients with advanced disease is poor with no effective therapies. The genetic bases of these tumors have been partially revealed in recent studies reporting genetic alterations such as amplifications of MYC (primarily in radiation-associated angiosarcomas), inactivating mutations in PTPRB and R707Q hotspot mutations of PLCG1. Here, we performed a comprehensive genomic analysis of 34 angiosarcomas using a clinically-approved, hybridization-based targeted next-generation sequencing assay for 341 well-established oncogenes and tumor suppressor genes. Over half of the angiosarcomas (n = 18, 53%) harbored genetic alterations affecting the MAPK pathway, involving mutations in KRAS, HRAS, NRAS, BRAF, MAPK1 and NF1, or amplifications in MAPK1/CRKL, CRAF or BRAF. The most frequently detected genetic aberrations were mutations in TP53 in 12 tumors (35%) and losses of CDKN2A in 9 tumors (26%). MYC amplifications were generally mutually exclusive of TP53 alterations and CDKN2A loss and were identified in 8 tumors (24%), most of which (n = 7, 88%) arose post-irradiation. Previously reported mutations in PTPRB (n = 10, 29%) and one (3%) PLCG1 R707Q mutation were also identified. Our results demonstrate that angiosarcomas are a genetically heterogeneous group of tumors, harboring a wide range of genetic alterations. The high frequency of genetic events affecting the MAPK pathway suggests that targeted therapies inhibiting MAPK signaling may be promising therapeutic avenues in patients with advanced angiosarcomas. PMID:26440310

Connectome-harmonic decomposition of human brain activity reveals dynamical repertoire re-organization under LSD.

Science.gov (United States)

Atasoy, Selen; Roseman, Leor; Kaelen, Mendel; Kringelbach, Morten L; Deco, Gustavo; Carhart-Harris, Robin L

2017-12-15

Recent studies have started to elucidate the effects of lysergic acid diethylamide (LSD) on the human brain but the underlying dynamics are not yet fully understood. Here we used 'connectome-harmonic decomposition', a novel method to investigate the dynamical changes in brain states. We found that LSD alters the energy and the power of individual harmonic brain states in a frequency-selective manner. Remarkably, this leads to an expansion of the repertoire of active brain states, suggestive of a general re-organization of brain dynamics given the non-random increase in co-activation across frequencies. Interestingly, the frequency distribution of the active repertoire of brain states under LSD closely follows power-laws indicating a re-organization of the dynamics at the edge of criticality. Beyond the present findings, these methods open up for a better understanding of the complex brain dynamics in health and disease.

Transcriptome, expression, and activity analyses reveal a vital heat shock protein 70 in the stress response of stony coral Pocillopora damicornis.

Science.gov (United States)

Zhang, Yidan; Zhou, Zhi; Wang, Lingui; Huang, Bo

2018-02-12

Coral bleaching occurs worldwide with increasing frequencies and intensities, which is caused by the stress response of stony coral to environmental change, especially increased sea surface temperature. In the present study, transcriptome, expression, and activity analyses were employed to illustrate the underlying molecular mechanisms of heat shock protein 70 (HSP70) in the stress response of coral to environmental changes. The domain analyses of assembled transcripts revealed 30 HSP70 gene contigs in stony coral Pocillopora damicornis. One crucial HSP70 (PdHSP70) was observed, whose expressions were induced by both elevated temperature and ammonium after expression difference analysis. The complete complementary DNA (cDNA) sequence of PdHSP70 was identified, which encoded a polypeptide of 650 amino acids with a molecular weight of 71.93 kDa. The deduced amino acid sequence of PdHSP70 contained a HSP70 domain (from Pro8 to Gly616), and it shared the highest similarity (95%) with HSP70 from Stylophora pistillata. The expression level of PdHSP70 gene increased significantly at 12 h, and returned to the initial level at 24 h after the stress of high temperature (32 °C). The cDNA fragment encoding the mature peptide of PdHSP70 was recombined and expressed in the prokaryotic expression system. The ATPase activity of recombinant PdHSP70 protein was determined, and it did not change significantly in a wide range of temperature from 25 to 40 °C. These results collectively suggested that PdHSP70 was a vital heat shock protein 70 in the stony coral P. damicornis, whose mRNA expression could be induced by diverse environmental stress and whose activity could remain stable under heat stress. PdHSP70 might be involved in the regulation of the bleaching owing to heat stress in the stony coral P. damicornis.

Cell kinetics of the marine sponge Halisarca caerulea reveal rapid cell turnover and shedding

NARCIS (Netherlands)

Goeij, de J.M.; Kluijver, de A.; Duyl, van F.C.; Vacelet, J.; Wijffels, R.H.; Goeij, de A.F.P.M.; Cleutjens, J.P.M.; Schutte, B.

2009-01-01

This study reveals the peculiar in vivo cell kinetics and cell turnover of the marine sponge Halisarca caerulea under steady-state conditions. The tropical coral reef sponge shows an extremely high proliferation activity, a short cell cycle duration and massive cell shedding. Cell turnover is

Crystallographic Analysis Reveals a Novel Second Binding Site for Trimethoprim in Active Site Double Mutants of Human Dihydrofolate Reductase†,‡

Science.gov (United States)

Cody, Vivian; Pace, Jim; Piraino, Jennifer; Queener, Sherry F.

2011-01-01

In order to produce a more potent replacement for trimethoprim (TMP) used as a therapy for Pneumocystis pneumonia and targets dihydrofolate reductase from Pneumocystis jirovecii (pjDHFR), it is necessary to understand the determinants of potency and selectivity against DHFR from the mammalian host and fungal pathogen cells. To this end, active site residues in human (h)DHFR were replaced with those from pjDHFR. Structural data are reported for two complexes of TMP with the double mutants Gln35Ser/Asn64Phe (Q35S/N64F) and Gln35Lys/Asn64Phe (Q35K/N64F) of hDHFR that unexpectedly show evidence for the binding of two molecules of TMP: one molecule that binds in the normal folate binding site and the second molecule that binds in a novel subpocket site such that the mutated residue Phe64 is involved in van der Waals contacts to the trimethoxyphenyl ring of the second TMP molecule. Kinetic data for the binding of TMP to hDHFR and pjDHFR reveal an 84-fold selectivity of TMP against pjDHFR (Ki 49 nM) compared to hDHFR (Ki 4093 nM). Two mutants that contain one substitution from pj- and one from the closely related Pneumocystis carinii DHFR (pcDHFR) (Q35K/N64F and Q35S/N64F) show Ki values of 593 and 617 nM, respectively; these Ki values are well above both the Ki for pjDHFR and are similar to pcDHFR (Q35K/N64F) and Q35S/N64F) (305 nM). These results suggest that active site residues 35 and 64 play key roles in determining selectivity for pneumocystis DHFR, but that other residues contribute to the unique binding of inhibitors to these enzymes. PMID:21684339

Disulfide bond within mu-calpain active site inhibits activity and autolysis.

Science.gov (United States)

Lametsch, René; Lonergan, Steven; Huff-Lonergan, Elisabeth

2008-09-01

Oxidative processes have the ability to influence mu-calpain activity. In the present study the influence of oxidation on activity and autolysis of mu-calpain was examined. Furthermore, LC-MS/MS analysis was employed to identify and characterize protein modifications caused by oxidation. The results revealed that the activity of mu-calpain is diminished by oxidation with H2O2 in a reversible manner involving cysteine and that the rate of autolysis of mu-calpain concomitantly slowed. The LC-MS/MS analysis of the oxidized mu-calpain revealed that the amino acid residues 105-133 contained a disulfide bond between Cys(108) and Cys(115). The finding that the active site cysteine in mu-calpain is able to form a disulfide bond has, to our knowledge, not been reported before. This could be part of a unique oxidation mechanism for mu-calpain. The results also showed that the formation of the disulfide bond is limited in the control (no oxidant added), and further limited in a concentration-dependent manner when beta-mercaptoethanol is added. However, the disulfide bond is still present to some extent in all conditions indicating that the active site cysteine is potentially highly susceptible to the formation of this intramolecular disulfide bond.

Multivariate pattern classification reveals autonomic and experiential representations of discrete emotions.

Science.gov (United States)

Kragel, Philip A; Labar, Kevin S

2013-08-01

Defining the structural organization of emotions is a central unresolved question in affective science. In particular, the extent to which autonomic nervous system activity signifies distinct affective states remains controversial. Most prior research on this topic has used univariate statistical approaches in attempts to classify emotions from psychophysiological data. In the present study, electrodermal, cardiac, respiratory, and gastric activity, as well as self-report measures were taken from healthy subjects during the experience of fear, anger, sadness, surprise, contentment, and amusement in response to film and music clips. Information pertaining to affective states present in these response patterns was analyzed using multivariate pattern classification techniques. Overall accuracy for classifying distinct affective states was 58.0% for autonomic measures and 88.2% for self-report measures, both of which were significantly above chance. Further, examining the error distribution of classifiers revealed that the dimensions of valence and arousal selectively contributed to decoding emotional states from self-report, whereas a categorical configuration of affective space was evident in both self-report and autonomic measures. Taken together, these findings extend recent multivariate approaches to study emotion and indicate that pattern classification tools may improve upon univariate approaches to reveal the underlying structure of emotional experience and physiological expression. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Deep Sequencing Reveals the Complete Genome and Evidence for Transcriptional Activity of the First Virus-Like Sequences Identified in Aristotelia chilensis (Maqui Berry

Directory of Open Access Journals (Sweden)

Javier Villacreses

2015-04-01

Full Text Available Here, we report the genome sequence and evidence for transcriptional activity of a virus-like element in the native Chilean berry tree Aristotelia chilensis. We propose to name the endogenous sequence as Aristotelia chilensis Virus 1 (AcV1. High-throughput sequencing of the genome of this tree uncovered an endogenous viral element, with a size of 7122 bp, corresponding to the complete genome of AcV1. Its sequence contains three open reading frames (ORFs: ORFs 1 and 2 shares 66%–73% amino acid similarity with members of the Caulimoviridae virus family, especially the Petunia vein clearing virus (PVCV, Petuvirus genus. ORF1 encodes a movement protein (MP; ORF2 a Reverse Transcriptase (RT and a Ribonuclease H (RNase H domain; and ORF3 showed no amino acid sequence similarity with any other known virus proteins. Analogous to other known endogenous pararetrovirus sequences (EPRVs, AcV1 is integrated in the genome of Maqui Berry and showed low viral transcriptional activity, which was detected by deep sequencing technology (DNA and RNA-seq. Phylogenetic analysis of AcV1 and other pararetroviruses revealed a closer resemblance with Petuvirus. Overall, our data suggests that AcV1 could be a new member of Caulimoviridae family, genus Petuvirus, and the first evidence of this kind of virus in a fruit plant.

Active methanotrophs in two contrasting North American peatland ecosystems revealed using DNA-SIP.

Science.gov (United States)

Gupta, Varun; Smemo, Kurt A; Yavitt, Joseph B; Basiliko, Nathan

2012-02-01

The active methanotroph community was investigated in two contrasting North American peatlands, a nutrient-rich sedge fen and nutrient-poor Sphagnum bog using in vitro incubations and (13)C-DNA stable-isotope probing (SIP) to measure methane (CH(4)) oxidation rates and label active microbes followed by fingerprinting and sequencing of bacterial and archaeal 16S rDNA and methane monooxygenase (pmoA and mmoX) genes. Rates of CH(4) oxidation were slightly, but significantly, faster in the bog and methanotrophs belonged to the class Alphaproteobacteria and were similar to other methanotrophs of the genera Methylocystis, Methylosinus, and Methylocapsa or Methylocella detected in, or isolated from, European bogs. The fen had a greater phylogenetic diversity of organisms that had assimilated (13)C, including methanotrophs from both the Alpha- and Gammaproteobacteria classes and other potentially non-methanotrophic organisms that were similar to bacteria detected in a UK and Finnish fen. Based on similarities between bacteria in our sites and those in Europe, including Russia, we conclude that site physicochemical characteristics rather than biogeography controlled the phylogenetic diversity of active methanotrophs and that differences in phylogenetic diversity between the bog and fen did not relate to measured CH(4) oxidation rates. A single crenarchaeon in the bog site appeared to be assimilating (13)C in 16S rDNA; however, its phylogenetic similarity to other CO(2)-utilizing archaea probably indicates that this organism is not directly involved in CH(4) oxidation in peat.

Inter-ring rotations of AAA ATPase p97 revealed by electron cryomicroscopy.

Science.gov (United States)

Yeung, Heidi O; Förster, Andreas; Bebeacua, Cecilia; Niwa, Hajime; Ewens, Caroline; McKeown, Ciarán; Zhang, Xiaodong; Freemont, Paul S

2014-03-05

The type II AAA+ protein p97 is involved in numerous cellular activities, including endoplasmic reticulum-associated degradation, transcription activation, membrane fusion and cell-cycle control. These activities are at least in part regulated by the ubiquitin system, in which p97 is thought to target ubiquitylated protein substrates within macromolecular complexes and assist in their extraction or disassembly. Although ATPase activity is essential for p97 function, little is known about how ATP binding or hydrolysis is coupled with p97 conformational changes and substrate remodelling. Here, we have used single-particle electron cryomicroscopy (cryo-EM) to study the effect of nucleotides on p97 conformation. We have identified conformational heterogeneity within the cryo-EM datasets from which we have resolved two major p97 conformations. A comparison of conformations reveals inter-ring rotations upon nucleotide binding and hydrolysis that may be linked to the remodelling of target protein complexes.

Anti-cancer agents in Saudi Arabian herbals revealed by automated high-content imaging

KAUST Repository

Hajjar, Dina

2017-06-13

Natural products have been used for medical applications since ancient times. Commonly, natural products are structurally complex chemical compounds that efficiently interact with their biological targets, making them useful drug candidates in cancer therapy. Here, we used cell-based phenotypic profiling and image-based high-content screening to study the mode of action and potential cellular targets of plants historically used in Saudi Arabia\\'s traditional medicine. We compared the cytological profiles of fractions taken from Juniperus phoenicea (Arar), Anastatica hierochuntica (Kaff Maryam), and Citrullus colocynthis (Hanzal) with a set of reference compounds with established modes of action. Cluster analyses of the cytological profiles of the tested compounds suggested that these plants contain possible topoisomerase inhibitors that could be effective in cancer treatment. Using histone H2AX phosphorylation as a marker for DNA damage, we discovered that some of the compounds induced double-strand DNA breaks. Furthermore, chemical analysis of the active fraction isolated from Juniperus phoenicea revealed possible anti-cancer compounds. Our results demonstrate the usefulness of cell-based phenotypic screening of natural products to reveal their biological activities.

Knockin of Cre Gene at Ins2 Locus Reveals No Cre Activity in Mouse Hypothalamic Neurons.

Science.gov (United States)

Li, Ling; Gao, Lin; Wang, Kejia; Ma, Xianhua; Chang, Xusheng; Shi, Jian-Hui; Zhang, Ye; Yin, Kai; Liu, Zhimin; Shi, Yuguang; Xie, Zhifang; Zhang, Weiping J

2016-02-02

The recombination efficiency and cell specificity of Cre driver lines are critical for exploring pancreatic β cell biology with the Cre/LoxP approach. Some commonly used Cre lines are based on the short Ins2 promoter fragment and show recombination activity in hypothalamic neurons; however, whether this stems from endogenous Ins2 promoter activity remains controversial. In this study, we generated Ins2-Cre knockin mice with a targeted insertion of IRES-Cre at the Ins2 locus and demonstrated with a cell lineage tracing study that the Ins2 gene is not transcriptionally active in the hypothalamus. The Ins2-Cre driver line displayed robust Cre expression and activity in pancreatic β cells without significant alterations in insulin expression. In the brain, Cre activity was mainly restricted to the choroid plexus, without significant recombination detected in the hippocampus or hypothalamus by the LacZ or fluorescent tdTomato reporters. Furthermore, Ins2-Cre mice exhibited normal glucose tolerance and insulin secretion upon glucose stimulation in vivo. In conclusion, this Ins2-Cre driver line allowed high-fidelity detection of endogenous Ins2 promoter activity in vivo, and the negative activity in the hypothalamus demonstrated that this system is a promising alternative tool for studying β cell biology.

Antifeedant activity of quassinoids.

Science.gov (United States)

Leskinen, V; Polonsky, J; Bhatnagar, S

1984-10-01

The antifeedant activity of 13 quassinoids of different structural types has been studied against the Mexican bean beetle (Epilachna varivestis Mulsant) 4th instar larvae and the southern armyworm (Spodoptera eridania Crawer) 5th instar larvae. All quassinoids tested displayed significant activity against the Mexican bean beetle and, thus, do not reveal a simple structure-activity relationship. Five quassinoids were active against the southern armyworm. Interestingly, four of these-bruceantin (I), glaucarubinone (VI), isobruceine A (VIII), and simalikalactone D (XI)-possess the required structural features for antineoplastic activity. The noncytotoxic quassin (X) is an exception; it is active against both pests.

Physical activity and health promotion strategies among ...

African Journals Online (AJOL)

Results: The findings revealed that 64% of the participants were physically active both within the work and recreation domains and 65% of the participants had good physical activity promoting practices. Discussing physical activity and giving out information regarding physical activity were most common methods used in ...

Toll-like receptor activation reveals developmental reorganization and unmasks responder subsets of microglia

NARCIS (Netherlands)

Scheffel, Joerg; Regen, Tommy; Van Rossum, Denise; Seifert, Stefanie; Ribes, Sandra; Nau, Roland; Parsa, Roham; Harris, Robert A.; Boddeke, Hendrikus W. G. M.; Chuang, Han-Ning; Pukrop, Tobias; Wessels, Johannes T.; Juergens, Tanja; Merkler, Doron; Brueck, Wolfgang; Schnaars, Mareike; Simons, Mikael; Kettenmann, Helmut; Hanisch, Uwe-Karsten

2012-01-01

The sentinel and immune functions of microglia require rapid and appropriate reactions to infection and damage. Their Toll-like receptors (TLRs) sense both as threats. However, whether activated microglia mount uniform responses or whether subsets conduct selective tasks is unknown. We demonstrate

Synthesis of Isomeric Phosphoubiquitin Chains Reveals that Phosphorylation Controls Deubiquitinase Activity and Specificity

Directory of Open Access Journals (Sweden)

Nicolas Huguenin-Dezot

2016-07-01

Full Text Available Ubiquitin is post-translationally modified by phosphorylation at several sites, but the consequences of these modifications are largely unknown. Here, we synthesize multi-milligram quantities of ubiquitin phosphorylated at serine 20, serine 57, and serine 65 via genetic code expansion. We use these phosphoubiquitins for the enzymatic assembly of 20 isomeric phosphoubiquitin dimers, with different sites of isopeptide linkage and/or phosphorylation. We discover that phosphorylation of serine 20 on ubiquitin converts UBE3C from a dual-specificity E3 ligase into a ligase that primarily synthesizes K48 chains. We profile the activity of 31 deubiquitinases on the isomeric phosphoubiquitin dimers in 837 reactions, and we discover that phosphorylation at distinct sites in ubiquitin can activate or repress cleavage of a particular linkage by deubiquitinases and that phosphorylation at a single site in ubiquitin can control the specificity of deubiquitinases for distinct ubiquitin linkages.

Large heterogeneities in comet 67P as revealed by active pits from sinkhole collapse.

Science.gov (United States)

Vincent, Jean-Baptiste; Bodewits, Dennis; Besse, Sébastien; Sierks, Holger; Barbieri, Cesare; Lamy, Philippe; Rodrigo, Rafael; Koschny, Detlef; Rickman, Hans; Keller, Horst Uwe; Agarwal, Jessica; A'Hearn, Michael F; Auger, Anne-Thérèse; Barucci, M Antonella; Bertaux, Jean-Loup; Bertini, Ivano; Capanna, Claire; Cremonese, Gabriele; Da Deppo, Vania; Davidsson, Björn; Debei, Stefano; De Cecco, Mariolino; El-Maarry, Mohamed Ramy; Ferri, Francesca; Fornasier, Sonia; Fulle, Marco; Gaskell, Robert; Giacomini, Lorenza; Groussin, Olivier; Guilbert-Lepoutre, Aurélie; Gutierrez-Marques, P; Gutiérrez, Pedro J; Güttler, Carsten; Hoekzema, Nick; Höfner, Sebastian; Hviid, Stubbe F; Ip, Wing-Huen; Jorda, Laurent; Knollenberg, Jörg; Kovacs, Gabor; Kramm, Rainer; Kührt, Ekkehard; Küppers, Michael; La Forgia, Fiorangela; Lara, Luisa M; Lazzarin, Monica; Lee, Vicky; Leyrat, Cédric; Lin, Zhong-Yi; Lopez Moreno, Josè J; Lowry, Stephen; Magrin, Sara; Maquet, Lucie; Marchi, Simone; Marzari, Francesco; Massironi, Matteo; Michalik, Harald; Moissl, Richard; Mottola, Stefano; Naletto, Giampiero; Oklay, Nilda; Pajola, Maurizio; Preusker, Frank; Scholten, Frank; Thomas, Nicolas; Toth, Imre; Tubiana, Cecilia

2015-07-02

Pits have been observed on many cometary nuclei mapped by spacecraft. It has been argued that cometary pits are a signature of endogenic activity, rather than impact craters such as those on planetary and asteroid surfaces. Impact experiments and models cannot reproduce the shapes of most of the observed cometary pits, and the predicted collision rates imply that few of the pits are related to impacts. Alternative mechanisms like explosive activity have been suggested, but the driving process remains unknown. Here we report that pits on comet 67P/Churyumov-Gerasimenko are active, and probably created by a sinkhole process, possibly accompanied by outbursts. We argue that after formation, pits expand slowly in diameter, owing to sublimation-driven retreat of the walls. Therefore, pits characterize how eroded the surface is: a fresh cometary surface will have a ragged structure with many pits, while an evolved surface will look smoother. The size and spatial distribution of pits imply that large heterogeneities exist in the physical, structural or compositional properties of the first few hundred metres below the current nucleus surface.

Spherical Harmonics Reveal Standing EEG Waves and Long-Range Neural Synchronization during Non-REM Sleep

OpenAIRE

Sivakumar, Siddharth S.; Namath, Amalia G.; Galán, Roberto F.

2016-01-01

Previous work from our lab has demonstrated how the connectivity of brain circuits constrains the repertoire of activity patterns that those circuits can display. Specifically, we have shown that the principal components of spontaneous neural activity are uniquely determined by the underlying circuit connections, and that although the principal components do not uniquely resolve the circuit structure, they do reveal important features about it. Expanding upon this framework on a larger scale ...

Deficiency in the mitochondrial apoptotic pathway reveals the toxic potential of autophagy under ER stress conditions.

Science.gov (United States)

Deegan, Shane; Saveljeva, Svetlana; Logue, Susan E; Pakos-Zebrucka, Karolina; Gupta, Sanjeev; Vandenabeele, Peter; Bertrand, Mathieu J M; Samali, Afshin

2014-01-01

Endoplasmic reticulum (ER) stress-induced cell death is normally associated with activation of the mitochondrial apoptotic pathway, which is characterized by CYCS (cytochrome c, somatic) release, apoptosome formation, and caspase activation, resulting in cell death. In this study, we demonstrate that under conditions of ER stress cells devoid of CASP9/caspase-9 or BAX and BAK1, and therefore defective in the mitochondrial apoptotic pathway, still undergo a delayed form of cell death associated with the activation of caspases, therefore revealing the existence of an alternative stress-induced caspase activation pathway. We identified CASP8/caspase-8 as the apical protease in this caspase cascade, and found that knockdown of either of the key autophagic genes, ATG5 or ATG7, impacted on CASP8 activation and cell death induction, highlighting the crucial role of autophagy in the activation of this novel ER stress-induced death pathway. In line with this, we identified a protein complex composed of ATG5, FADD, and pro-CASP8 whose assembly coincides with caspase activation and cell death induction. Together, our results reveal the toxic potential of autophagy in cells undergoing ER stress that are defective in the mitochondrial apoptotic pathway, and suggest a model in which the autophagosome functions as a platform facilitating pro-CASP8 activation. Chemoresistance, a common problem in the treatment of cancer, is frequently caused by the downregulation of key mitochondrial death effector proteins. Alternate stress-induced apoptotic pathways, such as the one described here, may become of particular relevance for tackling the problem of chemoresistance in cancer cells.

Rhythmic Components in Extracranial Brain Signals Reveal Multifaceted Task Modulation of Overlapping Neuronal Activity.

Directory of Open Access Journals (Sweden)

Roemer van der Meij

Full Text Available Oscillatory neuronal activity is implicated in many cognitive functions, and its phase coupling between sensors may reflect networks of communicating neuronal populations. Oscillatory activity is often studied using extracranial recordings and compared between experimental conditions. This is challenging, because there is overlap between sensor-level activity generated by different sources, and this can obscure differential experimental modulations of these sources. Additionally, in extracranial data, sensor-level phase coupling not only reflects communicating populations, but can also be generated by a current dipole, whose sensor-level phase coupling does not reflect source-level interactions. We present a novel method, which is capable of separating and characterizing sources on the basis of their phase coupling patterns as a function of space, frequency and time (trials. Importantly, this method depends on a plausible model of a neurobiological rhythm. We present this model and an accompanying analysis pipeline. Next, we demonstrate our approach, using magnetoencephalographic (MEG recordings during a cued tactile detection task as a case study. We show that the extracted components have overlapping spatial maps and frequency content, which are difficult to resolve using conventional pairwise measures. Because our decomposition also provides trial loadings, components can be readily contrasted between experimental conditions. Strikingly, we observed heterogeneity in alpha and beta sources with respect to whether their activity was suppressed or enhanced as a function of attention and performance, and this happened both in task relevant and irrelevant regions. This heterogeneity contrasts with the common view that alpha and beta amplitude over sensory areas are always negatively related to attention and performance.

High-resolution mapping reveals links of HP1 with active and inactive chromatin components.

Directory of Open Access Journals (Sweden)

Elzo de Wit

2007-03-01

Full Text Available Heterochromatin protein 1 (HP1 is commonly seen as a key factor of repressive heterochromatin, even though a few genes are known to require HP1-chromatin for their expression. To obtain insight into the targeting of HP1 and its interplay with other chromatin components, we have mapped HP1-binding sites on Chromosomes 2 and 4 in Drosophila Kc cells using high-density oligonucleotide arrays and the DNA adenine methyltransferase identification (DamID technique. The resulting high-resolution maps show that HP1 forms large domains in pericentric regions, but is targeted to single genes on chromosome arms. Intriguingly, HP1 shows a striking preference for exon-dense genes on chromosome arms. Furthermore, HP1 binds along entire transcription units, except for 5' regions. Comparison with expression data shows that most of these genes are actively transcribed. HP1 target genes are also marked by the histone variant H3.3 and dimethylated histone 3 lysine 4 (H3K4me2, which are both typical of active chromatin. Interestingly, H3.3 deposition, which is usually observed along entire transcription units, is limited to the 5' ends of HP1-bound genes. Thus, H3.3 and HP1 are mutually exclusive marks on active chromatin. Additionally, we observed that HP1-chromatin and Polycomb-chromatin are nonoverlapping, but often closely juxtaposed, suggesting an interplay between both types of chromatin. These results demonstrate that HP1-chromatin is transcriptionally active and has extensive links with several other chromatin components.

Super-resolution microscopy reveals functional organization of dopamine transporters into cholesterol and neuronal activity-dependent nanodomains

DEFF Research Database (Denmark)

Rahbek-Clemmensen, Troels; Lycas, Matthew D.; Erlendsson, Simon

2017-01-01

is dynamically sequestrated into cholesterol-dependent nanodomains in the plasma membrane of presynaptic varicosities and neuronal projections of dopaminergic neurons. Stochastic optical reconstruction microscopy reveals irregular dopamine transporter nanodomains (∼70 nm mean diameter) that were highly sensitive...... to cholesterol depletion. Live photoactivated localization microscopy shows a similar dopamine transporter membrane organization in live heterologous cells. In neurons, dual-color dSTORM shows that tyrosine hydroxylase and vesicular monoamine transporter-2 are distinctively localized adjacent to...

Active Tension Network model reveals an exotic mechanical state realized in epithelial tissues

Science.gov (United States)

Noll, Nicholas; Mani, Madhav; Heemskerk, Idse; Streicha, Sebastian; Shraiman, Boris

Mechanical interactions play a crucial role in epithelial morphogenesis, yet understanding the complex mechanisms through which stress and deformation affect cell behavior remains an open problem. Here we formulate and analyze the Active Tension Network (ATN) model, which assumes that mechanical balance of cells is dominated by cortical tension and introduces tension dependent active remodeling of the cortex. We find that ATNs exhibit unusual mechanical properties: i) ATN behaves as a fluid at short times, but at long times it supports external tension, like a solid; ii) its mechanical equilibrium state has extensive degeneracy associated with a discrete conformal - ''isogonal'' - deformation of cells. ATN model predicts a constraint on equilibrium cell geometry, which we demonstrate to hold in certain epithelial tissues. We further show that isogonal modes are observed in a fruit fly embryo, accounting for the striking variability of apical area of ventral cells and helping understand the early phase of gastrulation. Living matter realizes new and exotic mechanical states, understanding which helps understand biological phenomena.

Genetically encoded pH-indicators reveal activity-dependent cytosolic acidification of Drosophila motor nerve termini in vivo

Science.gov (United States)

Rossano, Adam J; Chouhan, Amit K; Macleod, Gregory T

2013-01-01

All biochemical processes, including those underlying synaptic function and plasticity, are pH sensitive. Cytosolic pH (pHcyto) shifts are known to accompany nerve activity in situ, but technological limitations have prevented characterization of such shifts in vivo. Genetically encoded pH-indicators (GEpHIs) allow for tissue-specific in vivo measurement of pH. We expressed three different GEpHIs in the cytosol of Drosophila larval motor neurons and observed substantial presynaptic acidification in nerve termini during nerve stimulation in situ. SuperEcliptic pHluorin was the most useful GEpHI for studying pHcyto shifts in this model system. We determined the resting pH of the nerve terminal cytosol to be 7.30 ± 0.02, and observed a decrease of 0.16 ± 0.01 pH units when the axon was stimulated at 40 Hz for 4 s. Realkalinization occurred upon cessation of stimulation with a time course of 20.54 ± 1.05 s (τ). The chemical pH-indicator 2′,7′-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein corroborated these changes in pHcyto. Bicarbonate-derived buffering did not contribute to buffering of acid loads from short (≤4 s) trains of action potentials but did buffer slow (∼60 s) acid loads. The magnitude of cytosolic acid transients correlated with cytosolic Ca2+ increase upon stimulation, and partial inhibition of the plasma membrane Ca2+-ATPase, a Ca2+/H+ exchanger, attenuated pHcyto shifts. Repeated stimulus trains mimicking motor patterns generated greater cytosolic acidification (∼0.30 pH units). Imaging through the cuticle of intact larvae revealed spontaneous pHcyto shifts in presynaptic termini in vivo, similar to those seen in situ during fictive locomotion, indicating that presynaptic pHcyto shifts cannot be dismissed as artifacts of ex vivo preparations. PMID:23401611

Investigation of Slow-wave Activity Saturation during Surgical Anesthesia Reveals a Signature of Neural Inertia in Humans.

Science.gov (United States)

Warnaby, Catherine E; Sleigh, Jamie W; Hight, Darren; Jbabdi, Saad; Tracey, Irene

2017-10-01

Previously, we showed experimentally that saturation of slow-wave activity provides a potentially individualized neurophysiologic endpoint for perception loss during anesthesia. Furthermore, it is clear that induction and emergence from anesthesia are not symmetrically reversible processes. The observed hysteresis is potentially underpinned by a neural inertia mechanism as proposed in animal studies. In an advanced secondary analysis of 393 individual electroencephalographic data sets, we used slow-wave activity dose-response relationships to parameterize slow-wave activity saturation during induction and emergence from surgical anesthesia. We determined whether neural inertia exists in humans by comparing slow-wave activity dose responses on induction and emergence. Slow-wave activity saturation occurs for different anesthetics and when opioids and muscle relaxants are used during surgery. There was wide interpatient variability in the hypnotic concentrations required to achieve slow-wave activity saturation. Age negatively correlated with power at slow-wave activity saturation. On emergence, we observed abrupt decreases in slow-wave activity dose responses coincident with recovery of behavioral responsiveness in ~33% individuals. These patients are more likely to have lower power at slow-wave activity saturation, be older, and suffer from short-term confusion on emergence. Slow-wave activity saturation during surgical anesthesia implies that large variability in dosing is required to achieve a targeted potential loss of perception in individual patients. A signature for neural inertia in humans is the maintenance of slow-wave activity even in the presence of very-low hypnotic concentrations during emergence from anesthesia.

Gamma-irradiation activates biochemical systems: induction of nitrate reductase activity in plant callus.

OpenAIRE

Pandey, K N; Sabharwal, P S

1982-01-01

Gamma-irradiation induced high levels of nitrate reductase activity (NADH:nitrate oxidoreductase, EC 1.6.6.1) in callus of Haworthia mirabilis Haworth. Subcultures of gamma-irradiated tissues showed autonomous growth on minimal medium. We were able to mimic the effects of gamma-irradiation by inducing nitrate reductase activity in unirradiated callus with exogenous auxin and kinetin. These results revealed that induction of nitrate reductase activity by gamma-irradiation is mediated through i...

Artemin Crystal Structure Reveals Insights into Heparan Sulfate Binding

Energy Technology Data Exchange (ETDEWEB)

Silvian,L.; Jin, P.; Carmillo, P.; Boriack-Sjodin, P.; Pelletier, C.; Rushe, M.; Gong, B.; Sah, D.; Pepinsky, B.; Rossomando, A.

2006-01-01

Artemin (ART) promotes the growth of developing peripheral neurons by signaling through a multicomponent receptor complex comprised of a transmembrane tyrosine kinase receptor (cRET) and a specific glycosylphosphatidylinositol-linked co-receptor (GFR{alpha}3). Glial cell line-derived neurotrophic factor (GDNF) signals through a similar ternary complex but requires heparan sulfate proteoglycans (HSPGs) for full activity. HSPG has not been demonstrated as a requirement for ART signaling. We crystallized ART in the presence of sulfate and solved its structure by isomorphous replacement. The structure reveals ordered sulfate anions bound to arginine residues in the pre-helix and amino-terminal regions that were organized in a triad arrangement characteristic of heparan sulfate. Three residues in the pre-helix were singly or triply substituted with glutamic acid, and the resulting proteins were shown to have reduced heparin-binding affinity that is partly reflected in their ability to activate cRET. This study suggests that ART binds HSPGs and identifies residues that may be involved in HSPG binding.

X-ray changes of children with chronic renal insufficiency

International Nuclear Information System (INIS)

Ponhold, W.; Balzar, E.

1983-01-01

The typical changes of renal osteopathy are shown in the X-rays of 7 children with end-stage renal disease treated with chronic intermittent hemodialysis. The exact evaluation of the granular structural changes of the cranium, the evidence of osteomalacia because of the hazy appearance of the vertebrae and the broadening of the sacroilical joints depend highly on subjective judgement and the technical X-ray procedures used. Unmistakable radiological diagnoses can be made when a broadening of the metalphyseal zones, epiphysioloysis as well as characteristic changes in the finder phalanges (acroosteolyses, spiculae, tunnelation) are present. (Author)

[Differential diagnosis for detection of hyphae in tissue].

Science.gov (United States)

Tintelnot, K

2013-11-01

Usually the detection of hyphae in tissue is unmistakable evidence of a deep mycosis requiring antimycotic treatment. Micromorphology alone rarely allows a specific diagnosis, thus confusion is possible between Candida, Aspergillus, Alternaria and Fusarium species or several other fungal agents. If broad, nearly non-septated hyphae are detected histologically mucormycosis can be suspected. Detection of hyphae in tissue is always a cause for concern because therapeutic consequences must follow. Because therapeutic strategies may differ depending on the specific fungal agent, a suspected diagnosis should be supplemented by other methods, e.g. culture of unfixed specimens, by immunohistology or molecular biological methods.

Protease-activated receptor-2 stimulates intestinal epithelial chloride transport through activation of PLC and selective PKC isoforms.

Science.gov (United States)

van der Merwe, Jacques Q; Moreau, France; MacNaughton, Wallace K

2009-06-01

Serine proteases play important physiological roles through their activity at G protein-coupled protease-activated receptors (PARs). We examined the roles that specific phospholipase (PL) C and protein kinase (PK) C (PKC) isoforms play in the regulation of PAR(2)-stimulated chloride secretion in intestinal epithelial cells. Confluent SCBN epithelial monolayers were grown on Snapwell supports and mounted in modified Ussing chambers. Short-circuit current (I(sc)) responses to basolateral application of the selective PAR(2) activating peptide, SLIGRL-NH(2), were monitored as a measure of net electrogenic ion transport caused by PAR(2) activation. SLIGRL-NH(2) induced a transient I(sc) response that was significantly reduced by inhibitors of PLC (U73122), phosphoinositol-PLC (ET-18), phosphatidylcholine-PLC (D609), and phosphatidylinositol 3-kinase (PI3K; LY294002). Immunoblot analysis revealed the phosphorylation of both PLCbeta and PLCgamma following PAR(2) activation. Pretreatment of the cells with inhibitors of PKC (GF 109203X), PKCalpha/betaI (Gö6976), and PKCdelta (rottlerin), but not PKCzeta (selective pseudosubstrate inhibitor), also attenuated this response. Cellular fractionation and immunoblot analysis, as well as confocal immunocytochemistry, revealed increases of PKCbetaI, PKCdelta, and PKCepsilon, but not PKCalpha or PKCzeta, in membrane fractions following PAR(2) activation. Pretreatment of the cells with U73122, ET-18, or D609 inhibited PKC activation. Inhibition of PI3K activity only prevented PKCdelta translocation. Immunoblots revealed that PAR(2) activation induced phosphorylation of both cRaf and ERK1/2 via PKCdelta. Inhibition of PKCbetaI and PI3K had only a partial effect on this response. We conclude that basolateral PAR(2)-induced chloride secretion involves activation of PKCbetaI and PKCdelta via a PLC-dependent mechanism resulting in the stimulation of cRaf and ERK1/2 signaling.

Quantitative proteomics of the tonoplast reveals a role for glycolytic enzymes in salt tolerance.

Science.gov (United States)

Barkla, Bronwyn J; Vera-Estrella, Rosario; Hernández-Coronado, Marcela; Pantoja, Omar

2009-12-01

To examine the role of the tonoplast in plant salt tolerance and identify proteins involved in the regulation of transporters for vacuolar Na(+) sequestration, we exploited a targeted quantitative proteomics approach. Two-dimensional differential in-gel electrophoresis analysis of free flow zonal electrophoresis separated tonoplast fractions from control, and salt-treated Mesembryanthemum crystallinum plants revealed the membrane association of glycolytic enzymes aldolase and enolase, along with subunits of the vacuolar H(+)-ATPase V-ATPase. Protein blot analysis confirmed coordinated salt regulation of these proteins, and chaotrope treatment indicated a strong tonoplast association. Reciprocal coimmunoprecipitation studies revealed that the glycolytic enzymes interacted with the V-ATPase subunit B VHA-B, and aldolase was shown to stimulate V-ATPase activity in vitro by increasing the affinity for ATP. To investigate a physiological role for this association, the Arabidopsis thaliana cytoplasmic enolase mutant, los2, was characterized. These plants were salt sensitive, and there was a specific reduction in enolase abundance in the tonoplast from salt-treated plants. Moreover, tonoplast isolated from mutant plants showed an impaired ability for aldolase stimulation of V-ATPase hydrolytic activity. The association of glycolytic proteins with the tonoplast may not only channel ATP to the V-ATPase, but also directly upregulate H(+)-pump activity.

REVEAL: Software Documentation and Platform Migration

Science.gov (United States)

Wilson, Michael A.; Veibell, Victoir T.; Freudinger, Lawrence C.

2008-01-01

The Research Environment for Vehicle Embedded Analysis on Linux (REVEAL) is reconfigurable data acquisition software designed for network-distributed test and measurement applications. In development since 2001, it has been successfully demonstrated in support of a number of actual missions within NASA s Suborbital Science Program. Improvements to software configuration control were needed to properly support both an ongoing transition to operational status and continued evolution of REVEAL capabilities. For this reason the project described in this report targets REVEAL software source documentation and deployment of the software on a small set of hardware platforms different from what is currently used in the baseline system implementation. This report specifically describes the actions taken over a ten week period by two undergraduate student interns and serves as a final report for that internship. The topics discussed include: the documentation of REVEAL source code; the migration of REVEAL to other platforms; and an end-to-end field test that successfully validates the efforts.

Revisiting diversity: cultural variation reveals the constructed nature of emotion perception.

Science.gov (United States)

Gendron, Maria

2017-10-01

The extent of cultural variation in emotion perception has long been assumed to be bounded by underlying universality. A growing body of research reveals, however, that evidence of universality in emotion perception is method-bound. Without the assumption of underlying universality, new lines of inquiry become relevant. Accumulating evidence suggests that cultures vary in what cues are relevant to perceptions of emotion. Further, cultural groups vary in their spontaneous inferences; mental state inference does not appear to be the only, or even most routine, mode of perception across cultures. Finally, setting universality assumptions aside requires innovation in the theory and measurement of culture. Recent studies reveal the promise of refinements in psychological approaches to culture. Together, the available evidence is consistent with a view of emotion perceptions as actively constructed by perceivers to fit the social and physical constraints of their cultural worlds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Structure-activity relationships for flavone interactions with amyloid β reveal a novel anti-aggregatory and neuroprotective effect of 2',3',4'-trihydroxyflavone (2-D08).

Science.gov (United States)

Marsh, Dylan T; Das, Sukanya; Ridell, Jessica; Smid, Scott D

2017-07-15

Naturally-occurring flavonoids have well documented anti-aggregatory and neuroprotective properties against the hallmark toxic protein in Alzheimer's disease, amyloid β (Aβ). However the extensive diversity of flavonoids has limited the insight into the precise structure-activity relationships that confer such bioactive properties against the Aβ protein. In the present study we have characterised the Aβ binding properties, anti-aggregatory and neuroprotective effects of a discreet set of flavones, including the recently described novel protein sumoylation inhibitor 2',3',4'-trihydroxyflavone (2-D08). Quercetin, transilitin, jaceosidin, nobiletin and 2-D08 were incubated with human Aβ 1-42 for 48h in vitro and effects on Aβ fibrillisation kinetics and morphology measured using Thioflavin T (ThT) and electron microscopy respectively, in addition to effects on neuronal PC12 cell viability. Of the flavones studied, only quercetin, transilitin and 2-D08 significantly inhibited Aβ 1-42 aggregation and toxicity in PC12 cells. Of those, 2-D08 was the most effective inhibitor. The strong anti-amyloid activity of 2-D08 indicates that extensive hydroxylation in the B ring is the most important determinant of activity against β amyloid within the flavone scaffold. The lack of efficacy of jaceosidin and nobiletin indicate that extension of B ring hydroxylation with methoxyl groups result in an incremental loss of anti-fibrillar and neuroprotective activity, highlighting the constraint to vicinal hydroxyl groups in the B ring for effective inhibition of aggregation. These findings reveal further structural insights into anti-amyloid bioactivity of flavonoids in addition to a novel and efficacious anti-aggregatory and neuroprotective effect of the semi-synthetic flavone and sumoylation inhibitor 2',3',4'-trihydroxyflavone (2-D08). Such modified flavones may facilitate drug development targeting multiple pathways in neurodegenerative disease. Crown Copyright © 2017

The spatiotemporal pattern of Src activation at lipid rafts revealed by diffusion-corrected FRET imaging.

Directory of Open Access Journals (Sweden)

Shaoying Lu

2008-07-01

Full Text Available Genetically encoded biosensors based on fluorescence resonance energy transfer (FRET have been widely applied to visualize the molecular activity in live cells with high spatiotemporal resolution. However, the rapid diffusion of biosensor proteins hinders a precise reconstruction of the actual molecular activation map. Based on fluorescence recovery after photobleaching (FRAP experiments, we have developed a finite element (FE method to analyze, simulate, and subtract the diffusion effect of mobile biosensors. This method has been applied to analyze the mobility of Src FRET biosensors engineered to reside at different subcompartments in live cells. The results indicate that the Src biosensor located in the cytoplasm moves 4-8 folds faster (0.93+/-0.06 microm(2/sec than those anchored on different compartments in plasma membrane (at lipid raft: 0.11+/-0.01 microm(2/sec and outside: 0.18+/-0.02 microm(2/sec. The mobility of biosensor at lipid rafts is slower than that outside of lipid rafts and is dominated by two-dimensional diffusion. When this diffusion effect was subtracted from the FRET ratio images, high Src activity at lipid rafts was observed at clustered regions proximal to the cell periphery, which remained relatively stationary upon epidermal growth factor (EGF stimulation. This result suggests that EGF induced a Src activation at lipid rafts with well-coordinated spatiotemporal patterns. Our FE-based method also provides an integrated platform of image analysis for studying molecular mobility and reconstructing the spatiotemporal activation maps of signaling molecules in live cells.

Joint cross-correlation analysis reveals complex, time-dependent functional relationship between cortical neurons and arm electromyograms

Science.gov (United States)

Zhuang, Katie Z.; Lebedev, Mikhail A.

2014-01-01

Correlation between cortical activity and electromyographic (EMG) activity of limb muscles has long been a subject of neurophysiological studies, especially in terms of corticospinal connectivity. Interest in this issue has recently increased due to the development of brain-machine interfaces with output signals that mimic muscle force. For this study, three monkeys were implanted with multielectrode arrays in multiple cortical areas. One monkey performed self-timed touch pad presses, whereas the other two executed arm reaching movements. We analyzed the dynamic relationship between cortical neuronal activity and arm EMGs using a joint cross-correlation (JCC) analysis that evaluated trial-by-trial correlation as a function of time intervals within a trial. JCCs revealed transient correlations between the EMGs of multiple muscles and neural activity in motor, premotor and somatosensory cortical areas. Matching results were obtained using spike-triggered averages corrected by subtracting trial-shuffled data. Compared with spike-triggered averages, JCCs more readily revealed dynamic changes in cortico-EMG correlations. JCCs showed that correlation peaks often sharpened around movement times and broadened during delay intervals. Furthermore, JCC patterns were directionally selective for the arm-reaching task. We propose that such highly dynamic, task-dependent and distributed relationships between cortical activity and EMGs should be taken into consideration for future brain-machine interfaces that generate EMG-like signals. PMID:25210153

Sexual activity in old age

Directory of Open Access Journals (Sweden)

Chernyshkova Е. V.

2011-09-01

Full Text Available The article deals with the analysis of the principal factors influencing sexual activity of elderly persons. Data of foreign study and sociologic research carried out in Saratov region (2010 were used as the base for the analysis. It was revealed that the primary determinants of sexual activity in old age are the following: state of health, presence or absence of a partner, active lifestyle

A passionate way of being: A qualitative study revealing the passion spiral

Directory of Open Access Journals (Sweden)

Susanna M. Halonen

2014-06-01

Full Text Available Being engaged in an activity one is passionate about has been tied to feeling life is worth living for. Existing research in passion has explored this phenomenon purely using quantitative research methodology, and by tying an individual’s passion to a specific activity. In this study, passion was explored in semi-structured interviews with 12 participants. The qualitative grounded theory analysis revealed a passionate way of being, with passion being located in the individual rather than in a specific activity. A new phenomenon to positive psychology, a passionate way of being is about having a purpose, creating positive impact, and pursuing variety. These key elements, amongst others, created a reinforcing, self-sustaining spiral, which offered a route to hedonic and eudaimonic happiness, generally serving to enhance life (though it could also detract from life if it became overpowering.

Integrated Experimental and Model-based Analysis Reveals the Spatial Aspects of EGFR Activation Dynamics

Energy Technology Data Exchange (ETDEWEB)

Shankaran, Harish; Zhang, Yi; Chrisler, William B.; Ewald, Jonathan A.; Wiley, H. S.; Resat, Haluk

2012-10-02

The epidermal growth factor receptor (EGFR) belongs to the ErbB family of receptor tyrosine kinases, and controls a diverse set of cellular responses relevant to development and tumorigenesis. ErbB activation is a complex process involving receptor-ligand binding, receptor dimerization, phosphorylation, and trafficking (internalization, recycling and degradation), which together dictate the spatio-temporal distribution of active receptors within the cell. The ability to predict this distribution, and elucidation of the factors regulating it, would help to establish a mechanistic link between ErbB expression levels and the cellular response. Towards this end, we constructed mathematical models for deconvolving the contributions of receptor dimerization and phosphorylation to EGFR activation, and to examine the dependence of these processes on sub-cellular location. We collected experimental datasets for EGFR activation dynamics in human mammary epithelial cells, with the specific goal of model parameterization, and used the data to estimate parameters for several alternate models. Model-based analysis indicated that: 1) signal termination via receptor dephosphorylation in late endosomes, prior to degradation, is an important component of the response, 2) less than 40% of the receptors in the cell are phosphorylated at any given time, even at saturating ligand doses, and 3) receptor dephosphorylation rates at the cell surface and early endosomes are comparable. We validated the last finding by measuring EGFR dephosphorylation rates at various times following ligand addition both in whole cells, and in endosomes using ELISAs and fluorescent imaging. Overall, our results provide important information on how EGFR phosphorylation levels are regulated within cells. Further, the mathematical model described here can be extended to determine receptor dimer abundances in cells co-expressing various levels of ErbB receptors. This study demonstrates that an iterative cycle of

Activity-guided separation of Chromolaena odorata leaf extract reveals fractions with rice disease-reducing properties

DEFF Research Database (Denmark)

Rodriguez Algaba, Julian; Sørensen, Jens Christian; Sørensen, Hilmer

2015-01-01

with water and methanol and the extracts separated using a group separation system followed by analysis using capillary electrophoresis. The fractions from the extracts were tested in vitro and in planta using Bipolaris oryzae (cause of brown spot of rice) to test for their potential to reduce disease...... severity. Activity-guided separation of the C. odorata extracts indicated that compounds with activity could, at least partly, be isolated on a weakly acidic cation exchange column. Further purification yielded fractions with disease reducing effects of up to 72 % at 15 days after inoculation. Activity...... was found both in methanol and water extracts, indicating that the bioactive compound(s) are hydrophilic, low molecular weight compounds. The disease-reducing fractions did not display any direct antimicrobial effects, but data indicate that they protect the plants by induced resistance as evidenced from...

Representing Microbial Dormancy in Soil Decomposition Models Improves Model Performance and Reveals Key Ecosystem Controls on Microbial Activity

Science.gov (United States)

He, Y.; Yang, J.; Zhuang, Q.; Wang, G.; Liu, Y.

2014-12-01

Climate feedbacks from soils can result from environmental change and subsequent responses of plant and microbial communities and nutrient cycling. Explicit consideration of microbial life history traits and strategy may be necessary to predict climate feedbacks due to microbial physiology and community changes and their associated effect on carbon cycling. In this study, we developed an explicit microbial-enzyme decomposition model and examined model performance with and without representation of dormancy at six temperate forest sites with observed soil efflux ranged from 4 to 10 years across different forest types. We then extrapolated the model to all temperate forests in the Northern Hemisphere (25-50°N) to investigate spatial controls on microbial and soil C dynamics. Both models captured the observed soil heterotrophic respiration (RH), yet no-dormancy model consistently exhibited large seasonal amplitude and overestimation in microbial biomass. Spatially, the total RH from temperate forests based on dormancy model amounts to 6.88PgC/yr, and 7.99PgC/yr based on no-dormancy model. However, no-dormancy model notably overestimated the ratio of microbial biomass to SOC. Spatial correlation analysis revealed key controls of soil C:N ratio on the active proportion of microbial biomass, whereas local dormancy is primarily controlled by soil moisture and temperature, indicating scale-dependent environmental and biotic controls on microbial and SOC dynamics. These developments should provide essential support to modeling future soil carbon dynamics and enhance the avenue for collaboration between empirical soil experiment and modeling in the sense that more microbial physiological measurements are needed to better constrain and evaluate the models.

Physical Activity During School

DEFF Research Database (Denmark)

Østergaard, Lars Domino

It is important, not only on health grounds, to exercise and to be physically active. In school, physical activities have shown to improve the students’ academic behaviour resulting in improved attention and information processing as well as enhanced coping. To stimulate and motivate students...... to be even more active during school hours further enhancing their academic behaviour, it is important to know when, why and how they are active, and their attitude towards different types of physical activities. Therefore, the aim of this study was to categorize the physical activities attended by students...... during school hours and to elucidate their attitude towards the different types of activities. The data consisted of observations of lessons followed by group interviews. Analyses of the observations revealed six categories of physical activities, varying from mandatory physical activities, activities...

Revealing Physical Activity of GRB Central Engine with Macronova/Kilonova Data

Energy Technology Data Exchange (ETDEWEB)

Shen, Zhao-Qiang; Jin, Zhi-Ping; Liang, Yun-Feng; Li, Xiang; Fan, Yi-Zhong; Wei, Da-Ming, E-mail: yzfan@pmo.ac.cn, E-mail: dmwei@pmo.ac.cn [Key Laboratory of dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Science, Nanjing 210008 (China)

2017-02-01

The modeling of Li-Paczyński macronova/kilonova signals gives a reasonable estimate on the neutron-rich material ejected during the neutron star mergers. Usually the accretion disk is more massive than the macronova ejecta, with which the efficiencies of converting the disk mass into prompt emission of three merger-driven GRBs can hence be directly constrained. Supposing the macronovae/kilonovae associated with GRB 050709, GRB 060614, and GRB 130603B arose from radioactive decay of the r -process material, the upper limit on energy conversion efficiencies are found to be as low as ∼10{sup −6}–10{sup −4}. Moreover, for all three events, neutrino annihilation is likely powerful enough to account for the brief gamma-ray flashes. Neutrino annihilation can also explain the “extended” emission lasting ∼100 s in GRB 050709, but does not work for the one in GRB 060614. These progresses demonstrate that the macronova can serve as a novel probe of the central engine activity.

Revealing conceptual understanding of international business

NARCIS (Netherlands)

Sue Ashley; Dr. Harmen Schaap; Prof.Dr. Elly de Bruijn

2017-01-01

This study aims to identify an adequate approach for revealing conceptual understanding in higher professional education. Revealing students’ conceptual understanding is an important step towards developing effective curricula, assessment and aligned teaching strategies to enhance conceptual

Mathematics revealed

CERN Document Server

Berman, Elizabeth

1979-01-01

Mathematics Revealed focuses on the principles, processes, operations, and exercises in mathematics.The book first offers information on whole numbers, fractions, and decimals and percents. Discussions focus on measuring length, percent, decimals, numbers as products, addition and subtraction of fractions, mixed numbers and ratios, division of fractions, addition, subtraction, multiplication, and division. The text then examines positive and negative numbers and powers and computation. Topics include division and averages, multiplication, ratios, and measurements, scientific notation and estim

Disease-linked mutations in factor H reveal pivotal role of cofactor activity in self-surface-selective regulation of complement activation.

Science.gov (United States)

Kerr, Heather; Wong, Edwin; Makou, Elisavet; Yang, Yi; Marchbank, Kevin; Kavanagh, David; Richards, Anna; Herbert, Andrew P; Barlow, Paul N

2017-08-11

Spontaneous activation enables the complement system to respond very rapidly to diverse threats. This activation is efficiently suppressed by complement factor H (CFH) on self-surfaces but not on foreign surfaces. The surface selectivity of CFH, a soluble protein containing 20 complement-control protein modules (CCPs 1-20), may be compromised by disease-linked mutations. However, which of the several functions of CFH drives this self-surface selectivity remains unknown. To address this, we expressed human CFH mutants in Pichia pastoris We found that recombinant I62-CFH (protective against age-related macular degeneration) and V62-CFH functioned equivalently, matching or outperforming plasma-derived CFH, whereas R53H-CFH, linked to atypical hemolytic uremic syndrome (aHUS), was defective in C3bBb decay-accelerating activity (DAA) and factor I cofactor activity (CA). The aHUS-linked CCP 19 mutant D1119G-CFH had virtually no CA on (self-like) sheep erythrocytes ( E S ) but retained DAA. The aHUS-linked CCP 20 mutant S1191L/V1197A-CFH (LA-CFH) had dramatically reduced CA on E S but was less compromised in DAA. D1119G-CFH and LA-CFH both performed poorly at preventing complement-mediated hemolysis of E S PspCN, a CFH-binding Streptococcus pneumoniae protein domain, binds CFH tightly and increases accessibility of CCPs 19 and 20. PspCN did not improve the DAA of any CFH variant on E S Conversely, PspCN boosted the CA, on E S , of I62-CFH, R53H-CFH, and LA-CFH and also enhanced hemolysis protection by I62-CFH and LA-CFH. We conclude that CCPs 19 and 20 are critical for efficient CA on self-surfaces but less important for DAA. Exposing CCPs 19 and 20 with PspCN and thus enhancing CA on self-surfaces may reverse deficiencies of some CFH variants. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Human glial chimeric mice reveal astrocytic dependence of JC virus infection

DEFF Research Database (Denmark)

Kondo, Yoichi; Windrem, Martha S; Zou, Lisa

2014-01-01

with humanized white matter by engrafting human glial progenitor cells (GPCs) into neonatal immunodeficient and myelin-deficient mice. Intracerebral delivery of JCV resulted in infection and subsequent demyelination of these chimeric mice. Human GPCs and astrocytes were infected more readily than...... that was chimeric for human astrocytes and GPCs. JCV effectively propagated in these mice, which indicates that astroglial infection is sufficient for JCV spread. Sequencing revealed progressive mutation of the JCV capsid protein VP1 after infection, suggesting that PML may evolve with active infection...

Neuronal Population Activity in Spinal Motor Circuits

DEFF Research Database (Denmark)

Berg, Rune W.

2017-01-01

The core elements of stereotypical movements such as locomotion, scratching and breathing are generated by networks in the lower brainstem and the spinal cord. Ensemble activities in spinal motor networks had until recently been merely a black box, but with the emergence of ultra-thin Silicon multi......-electrode technology it was possible to reveal the spiking activity of larger parts of the network. A series of experiments revealed unexpected features of spinal networks, such as multiple spiking regimes and lognormal firing rate distributions. The lognormality renders the widespread idea of a typical firing rate...

Focus group interviews reveal reasons for differences in the perception of disease activity in rheumatoid arthritis

NARCIS (Netherlands)

M.J. Walter (Margot); van’t Spijker, A. (Adriaan); A. Pasma (Annelieke); J.M.W. Hazes (Mieke); J.J. Luime (Jolanda)

2017-01-01

textabstractObjective: Doctors frequently see patients who have difficulties coping with their disease and rate their disease activity high, despite the fact that according to the doctors, the disease activity is low. This study explored the patients’ perspectives on this discordance that may help

Effects of curricular activity on students' situational motivation and physical activity levels.

Science.gov (United States)

Gao, Zan; Hannon, James C; Newton, Maria; Huang, Chaoqun

2011-09-01

The purpose of this study was to examine (a) the effects of three curricular activities on students'situational motivation (intrinsic motivation [IM], identified regulation [IR], external regulation, and amotivation [AM]) and physical activity (PA) levels, and (b) the predictive strength of situational motivation to PA levels. Four hundred twelve students in grades 7-9 participated in three activities (cardiovascular fitness, ultimate football, and Dance Dance Revolution [DDR]) in physical education. ActiGraph GT1M accelerometers were used to measure students' PA levels for three classes for each activity. Students also completed a Situational Motivation Scale (Guay, Vallerand, & Blanchard, 2000) at the end of each class. Multivariate analysis of variance revealed that students spent significantly higher percentages of time in moderate-to-vigorous PA (MVPA) in fitness and football classes than they did in DDR class. Students reported higher lM and IR toward fitness than DDR They also scored higher in IR toward fitness than football. In contrast, students displayed significantly lower AM toward fitness than football and DDR Hierarchical Linear Modeling revealed that IM was the only positive predictor for time in MVPA (p = .02), whereas AM was the negative predictor (p < .01). The findings are discussed in regard to the implications for educational practice.

Comparison of Cytotoxic Activity in Leukemic Lineages Reveals Important Features of β-Hairpin Antimicrobial Peptides.

Science.gov (United States)

Buri, Marcus V; Torquato, Heron F Vieira; Barros, Carlos Castilho; Ide, Jaime S; Miranda, Antonio; Paredes-Gamero, Edgar J

2017-07-01

Several reports described different modes of cell death triggered by antimicrobial peptides (AMPs) due to direct effects on membrane disruption, and more recently by apoptosis and necrosis-like patterns. Cytotoxic curves of four β-hairpin AMPs (gomesin, protegrin, tachyplesin, and polyphemusin) were obtained from several human leukemic lineages and normal monocytes and Two cell lines were then selected based on their cytotoxic sensitivity. One was sensitive to AMPs (K562) and the other resistant (KG-1) and their effect compared between these lineages. Thus, these lineages were chosen to further investigate biological features related with their cytotoxicities to AMPs. Stimulation with AMPs produced cell death, with activation of caspase-3, in K562 lineage. Increase on the fluidity of plasmatic membrane by reducing cholesterol potentiated cytotoxicity of AMPs in both lineages. Quantification of internal and external gomesin binding to the cellular membrane of both K562 and KG-1 cells showed that more peptide is accumulated inside of K562 cells. Additionally, evaluation of multi-drug resistant pumps activity showed that KG-1 has more activity than K562 lineage. A comparison of intrinsic gene patterns showed great differences between K562 and KG-1, but stimulation with gomesin promoted few changes in gene expression patterns. Differences in internalization process through the plasma membrane, multidrug resistance pumps activity, and gene expression pattern are important features to AMPs regulated cell death. J. Cell. Biochem. 118: 1764-1773, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Perceived climate in physical activity settings.

Science.gov (United States)

Gill, Diane L; Morrow, Ronald G; Collins, Karen E; Lucey, Allison B; Schultz, Allison M

2010-01-01

This study focused on the perceived climate for LGBT youth and other minority groups in physical activity settings. A large sample of undergraduates and a selected sample including student teachers/interns and a campus Pride group completed a school climate survey and rated the climate in three physical activity settings (physical education, organized sport, exercise). Overall, school climate survey results paralleled the results with national samples revealing high levels of homophobic remarks and low levels of intervention. Physical activity climate ratings were mid-range, but multivariate analysis of variation test (MANOVA) revealed clear differences with all settings rated more inclusive for racial/ethnic minorities and most exclusive for gays/lesbians and people with disabilities. The results are in line with national surveys and research suggesting sexual orientation and physical characteristics are often the basis for harassment and exclusion in sport and physical activity. The current results also indicate that future physical activity professionals recognize exclusion, suggesting they could benefit from programs that move beyond awareness to skills and strategies for creating more inclusive programs.

Quantitative cell signalling analysis reveals down-regulation of MAPK pathway activation in colorectal cancer.

LENUS (Irish Health Repository)

Gulmann, Christian

2009-08-01

Mitogen-activated protein kinases (MAPK) are considered to play significant roles in colonic carcinogenesis and kinase inhibitor therapy has been proposed as a potential tool in the treatment of this disease. Reverse-phase microarray assays using phospho-specific antibodies can directly measure levels of phosphorylated protein isoforms. In the current study, samples from 35 cases of untreated colorectal cancer colectomies were laser capture-microdissected to isolate epithelium and stroma from cancer as well as normal (i.e. uninvolved) mucosa. Lysates generated from these four tissue types were spotted onto reverse-phase protein microarrays and probed with a panel of antibodies to ERK, p-ERK, p38, p-p38, p-JNK, MEK and p-MEK. Whereas total protein levels were unchanged, or slightly elevated (p38, p = 0.0025) in cancers, activated isoforms, including p-ERK, p-p38 and p-JNK, were decreased two- to four-fold in cancers compared with uninvolved mucosa (p < 0.0023 in all cases except for p-JNK in epithelium, where decrement was non-significant). This was backed up by western blotting. Dukes\\' stage B and C cancers displayed lower p-ERK and p-p38 expression than Dukes\\' stage A cancers, although this was not statistically significant. It is concluded that MAPK activity may be down-regulated in colorectal cancer and that further exploration of inhibitory therapy in this system should be carefully evaluated if this finding is confirmed in larger series.

Digoxin reveals a functional connection between HIV-1 integration preference and T-cell activation.

Directory of Open Access Journals (Sweden)

Alexander Zhyvoloup

2017-07-01

Full Text Available HIV-1 integrates more frequently into transcribed genes, however the biological significance of HIV-1 integration targeting has remained elusive. Using a selective high-throughput chemical screen, we discovered that the cardiac glycoside digoxin inhibits wild-type HIV-1 infection more potently than HIV-1 bearing a single point mutation (N74D in the capsid protein. We confirmed that digoxin repressed viral gene expression by targeting the cellular Na+/K+ ATPase, but this did not explain its selectivity. Parallel RNAseq and integration mapping in infected cells demonstrated that digoxin inhibited expression of genes involved in T-cell activation and cell metabolism. Analysis of >400,000 unique integration sites showed that WT virus integrated more frequently than N74D mutant within or near genes susceptible to repression by digoxin and involved in T-cell activation and cell metabolism. Two main gene networks down-regulated by the drug were CD40L and CD38. Blocking CD40L by neutralizing antibodies selectively inhibited WT virus infection, phenocopying digoxin. Thus the selectivity of digoxin depends on a combination of integration targeting and repression of specific gene networks. The drug unmasked a functional connection between HIV-1 integration and T-cell activation. Our results suggest that HIV-1 evolved integration site selection to couple its early gene expression with the status of target CD4+ T-cells, which may affect latency and viral reactivation.

Digoxin reveals a functional connection between HIV-1 integration preference and T-cell activation.

Science.gov (United States)

Zhyvoloup, Alexander; Melamed, Anat; Anderson, Ian; Planas, Delphine; Lee, Chen-Hsuin; Kriston-Vizi, Janos; Ketteler, Robin; Merritt, Andy; Routy, Jean-Pierre; Ancuta, Petronela; Bangham, Charles R M; Fassati, Ariberto

2017-07-01

HIV-1 integrates more frequently into transcribed genes, however the biological significance of HIV-1 integration targeting has remained elusive. Using a selective high-throughput chemical screen, we discovered that the cardiac glycoside digoxin inhibits wild-type HIV-1 infection more potently than HIV-1 bearing a single point mutation (N74D) in the capsid protein. We confirmed that digoxin repressed viral gene expression by targeting the cellular Na+/K+ ATPase, but this did not explain its selectivity. Parallel RNAseq and integration mapping in infected cells demonstrated that digoxin inhibited expression of genes involved in T-cell activation and cell metabolism. Analysis of >400,000 unique integration sites showed that WT virus integrated more frequently than N74D mutant within or near genes susceptible to repression by digoxin and involved in T-cell activation and cell metabolism. Two main gene networks down-regulated by the drug were CD40L and CD38. Blocking CD40L by neutralizing antibodies selectively inhibited WT virus infection, phenocopying digoxin. Thus the selectivity of digoxin depends on a combination of integration targeting and repression of specific gene networks. The drug unmasked a functional connection between HIV-1 integration and T-cell activation. Our results suggest that HIV-1 evolved integration site selection to couple its early gene expression with the status of target CD4+ T-cells, which may affect latency and viral reactivation.

Functional gene profiling through metaRNAseq approach reveals diet-dependent variation in rumen microbiota of buffalo (Bubalus bubalis).

Science.gov (United States)

Hinsu, Ankit T; Parmar, Nidhi R; Nathani, Neelam M; Pandit, Ramesh J; Patel, Anand B; Patel, Amrutlal K; Joshi, Chaitanya G

2017-04-01

Recent advances in next generation sequencing technology have enabled analysis of complex microbial community from genome to transcriptome level. In the present study, metatranscriptomic approach was applied to elucidate functionally active bacteria and their biological processes in rumen of buffalo (Bubalus bubalis) adapted to different dietary treatments. Buffaloes were adapted to a diet containing 50:50, 75:25 and 100:0 forage to concentrate ratio, each for 6 weeks, before ruminal content sample collection. Metatranscriptomes from rumen fiber adherent and fiber-free active bacteria were sequenced using Ion Torrent PGM platform followed by annotation using MG-RAST server and CAZYmes (Carbohydrate active enzymes) analysis toolkit. In all the samples Bacteroidetes was the most abundant phylum followed by Firmicutes. Functional analysis using KEGG Orthology database revealed Metabolism as the most abundant category at level 1 within which Carbohydrate metabolism was dominating. Diet treatments also exerted significant differences in proportion of enzymes involved in metabolic pathways for VFA production. Carbohydrate Active Enzyme(CAZy) analysis revealed the abundance of genes encoding glycoside hydrolases with the highest representation of GH13 CAZy family in all the samples. The findings provide an overview of the activities occurring in the rumen as well as active bacterial population and the changes occurring through different dietary treatments. Copyright © 2017 Elsevier Ltd. All rights reserved.

An Unbiased View of the History of Polish Medical Physics by a Senior Polish Medical Physicist

International Nuclear Information System (INIS)

Chomicki, O. A.

2008-01-01

Here is a story told by Maria Sklodowska-Curie at the meeting of the International Committee of Intellectual Cooperation in 1921: 'In a free literary competition on the role and importance of elephants the Englishman's story was 'My adventures while shooting elephants in South Africa', the Frenchman was more concerned with 'The sexual and erotic life of elephants', while the Polish approach was invariably 'The elephant versus Poland's national independence', which seemed quite understandable in the light of over 120 years when Poland was partitioned and lost its independence. Since then this saying has become proverbial and came to express the unmistakably Polish tendency to see everything in terms of Polish interests. In my remarks and reminiscences on the history of the Polish Society of Medical Physics you will quickly recognize the same tendency. First, I will, among other things, try to open some old cupboards to 'produce good [things] from the store of good' (Matthew 12:35), especially concerning the first few years of the activity in medical physics in Poland, and second, I will draw some conclusions and/or offer suggestions based on what a senior medical physicist has seen for more than 50 years of his activity in this field. (author)

Nicotinamide riboside kinase structures reveal new pathways to NAD+.

Directory of Open Access Journals (Sweden)

Wolfram Tempel

2007-10-01

Full Text Available The eukaryotic nicotinamide riboside kinase (Nrk pathway, which is induced in response to nerve damage and promotes replicative life span in yeast, converts nicotinamide riboside to nicotinamide adenine dinucleotide (NAD+ by phosphorylation and adenylylation. Crystal structures of human Nrk1 bound to nucleoside and nucleotide substrates and products revealed an enzyme structurally similar to Rossmann fold metabolite kinases and allowed the identification of active site residues, which were shown to be essential for human Nrk1 and Nrk2 activity in vivo. Although the structures account for the 500-fold discrimination between nicotinamide riboside and pyrimidine nucleosides, no enzyme feature was identified to recognize the distinctive carboxamide group of nicotinamide riboside. Indeed, nicotinic acid riboside is a specific substrate of human Nrk enzymes and is utilized in yeast in a novel biosynthetic pathway that depends on Nrk and NAD+ synthetase. Additionally, nicotinic acid riboside is utilized in vivo by Urh1, Pnp1, and Preiss-Handler salvage. Thus, crystal structures of Nrk1 led to the identification of new pathways to NAD+.

Revealing Conceptual Understanding of International Business

Science.gov (United States)

Ashley, Sue; Schaap, Harmen; de Bruijn, Elly

2017-01-01

This study aims to identify an adequate approach for revealing conceptual understanding in higher professional education. Revealing students' conceptual understanding is an important step towards developing effective curricula, assessment and aligned teaching strategies to enhance conceptual understanding in higher education. Essays and concept…

Urease activity in different soils of Egypt.

Science.gov (United States)

el-Shinnawi, M M

1978-01-01

Samples from two depths (0--15 and 15--30 cm) of five Egyptian soils: sandy, calcareous, fertile alluvial, saline alluvial, and alkali alluvial were tested for urease activity. Samples were treated with farmyard manure at rates of 0 and 0.5% C, and moisture at levels of 50, 65, and 80% of the water holding capacity. The studied Egyptian soils showed different activities of urease. Decreases in the values were shown by depth of sampling and varied in their intensities according to soil type, except for saline soil which revealed an opposite trend by the higher activity of its sub-surface layer. Order of activity was the following: fertile, saline, alkali, calcareous, and sandy soil. Farmyard manure slightly increased the activity of the enzyme. Incubation of moistened samples revealed that the optimum moisture content was 50% of W.H.C. for the tested soils, except for saline which showed best results at 65% of W.H.C.

Creatine-induced activation of antioxidative defence in myotube cultures revealed by explorative NMR-based metabonomics and proteomics

Directory of Open Access Journals (Sweden)

Nielsen Niels

2010-02-01

Full Text Available Abstract Background Creatine is a key intermediate in energy metabolism and supplementation of creatine has been used for increasing muscle mass, strength and endurance. Creatine supplementation has also been reported to trigger the skeletal muscle expression of insulin like growth factor I, to increase the fat-free mass and improve cognition in elderly, and more explorative approaches like transcriptomics has revealed additional information. The aim of the present study was to reveal additional insight into the biochemical effects of creatine supplementation at the protein and metabolite level by integrating the explorative techniques, proteomics and NMR metabonomics, in a systems biology approach. Methods Differentiated mouse myotube cultures (C2C12 were exposed to 5 mM creatine monohydrate (CMH for 24 hours. For proteomics studies, lysed myotubes were analyzed in single 2-DGE gels where the first dimension of protein separation was pI 5-8 and second dimension was a 12.5% Criterion gel. Differentially expressed protein spots of significance were excised from the gel, desalted and identified by peptide mass fingerprinting using MALDI-TOF MS. For NMR metabonomic studies, chloroform/methanol extractions of the myotubes were subjected to one-dimensional 1H NMR spectroscopy and the intracellular oxidative status of myotubes was assessed by intracellular DCFH2 oxidation after 24 h pre-incubation with CMH. Results The identified differentially expressed proteins included vimentin, malate dehydrogenase, peroxiredoxin, thioredoxin dependent peroxide reductase, and 75 kDa and 78 kDa glucose regulated protein precursors. After CMH exposure, up-regulated proteomic spots correlated positively with the NMR signals from creatine, while down-regulated proteomic spots were negatively correlated with these NMR signals. The identified differentially regulated proteins were related to energy metabolism, glucose regulated stress, cellular structure and the

Revealing a steroid receptor ligand as a unique PPAR[gamma] agonist

Energy Technology Data Exchange (ETDEWEB)

Lin, Shengchen; Han, Ying; Shi, Yuzhe; Rong, Hui; Zheng, Songyang; Jin, Shikan; Lin, Shu-Yong; Lin, Sheng-Cai; Li, Yong (Pitt); (Xiamen)

2012-06-28

Peroxisome proliferator-activated receptor gamma (PPAR{gamma}) regulates metabolic homeostasis and is a molecular target for anti-diabetic drugs. We report here the identification of a steroid receptor ligand, RU-486, as an unexpected PPAR{gamma} agonist, thereby uncovering a novel signaling route for this steroid drug. Similar to rosiglitazone, RU-486 modulates the expression of key PPAR{gamma} target genes and promotes adipocyte differentiation, but with a lower adipogenic activity. Structural and functional studies of receptor-ligand interactions reveal the molecular basis for a unique binding mode for RU-486 in the PPAR{gamma} ligand-binding pocket with distinctive properties and epitopes, providing the molecular mechanisms for the discrimination of RU-486 from thiazolidinediones (TZDs) drugs. Our findings together indicate that steroid compounds may represent an alternative approach for designing non-TZD PPAR{gamma} ligands in the treatment of insulin resistance.

Trans-Binding Mechanism of Ubiquitin-like Protein Activation Revealed by a UBA5-UFM1 Complex

Directory of Open Access Journals (Sweden)

Walaa Oweis

2016-09-01

Full Text Available Modification of proteins by ubiquitin or ubiquitin-like proteins (UBLs is a critical cellular process implicated in a variety of cellular states and outcomes. A prerequisite for target protein modification by a UBL is the activation of the latter by activating enzymes (E1s. Here, we present the crystal structure of the non-canonical homodimeric E1, UBA5, in complex with its cognate UBL, UFM1, and supporting biochemical experiments. We find that UBA5 binds to UFM1 via a trans-binding mechanism in which UFM1 interacts with distinct sites in both subunits of the UBA5 dimer. This binding mechanism requires a region C-terminal to the adenylation domain that brings UFM1 to the active site of the adjacent UBA5 subunit. We also find that transfer of UFM1 from UBA5 to the E2, UFC1, occurs via a trans mechanism, thereby requiring a homodimer of UBA5. These findings explicitly elucidate the role of UBA5 dimerization in UFM1 activation.

Theoretical Insights Reveal Novel Motions in Csk's SH3 Domain That Control Kinase Activation.

Directory of Open Access Journals (Sweden)

Sulyman Barkho

Full Text Available The Src family of tyrosine kinases (SFKs regulate numerous aspects of cell growth and differentiation and are under the principal control of the C-terminal Src Kinase (Csk. Although Csk and SFKs share conserved kinase, SH2 and SH3 domains, they differ considerably in three-dimensional structure, regulatory mechanism, and the intrinsic kinase activities. Although the SH2 and SH3 domains are known to up- or down-regulate tyrosine kinase function, little is known about the global motions in the full-length kinase that govern these catalytic variations. We use a combination of accelerated Molecular Dynamics (aMD simulations and experimental methods to provide a new view of functional motions in the Csk scaffold. These computational studies suggest that high frequency vibrations in the SH2 domain are coupled through the N-terminal lobe of the kinase domain to motions in the SH3 domain. The effects of these reflexive movements on the kinase domain can be viewed using both Deuterium Exchange Mass Spectrometry (DXMS and steady-state kinetic methods. Removal of several contacts, including a crystallographically unobserved N-terminal segment, between the SH3 and kinase domains short-circuit these coupled motions leading to reduced catalytic efficiency and stability of N-lobe motifs within the kinase domain. The data expands the model of Csk's activation whereby separate domains productively interact with two diametrically opposed surfaces of the kinase domain. Such reversible transitions may organize the active structure of the tyrosine kinase domain of Csk.

Two crystal structures of dihydrofolate reductase-thymidylate synthase from Cryptosporidium hominis reveal protein–ligand interactions including a structural basis for observed antifolate resistance

Energy Technology Data Exchange (ETDEWEB)

Anderson, Amy C., E-mail: aca@dartmouth.edu [Dartmouth College, Department of Chemistry, Burke Laboratories, Hanover, NH 03755 (United States)

2005-03-01

An analysis of the protein–ligand interactions in two crystal structures of DHFR-TS from C. hominis reveals a possible structural basis for observed antifolate resistance in C. hominis DHFR. A comparison with the structure of human DHFR reveals residue substitutions that may be exploited for the design of species-selective inhibitors. Cryptosporidium hominis is a protozoan parasite that causes acute gastrointestinal illness. There are no effective therapies for cryptosporidiosis, highlighting the need for new drug-lead discovery. An analysis of the protein–ligand interactions in two crystal structures of dihydrofolate reductase-thymidylate synthase (DHFR-TS) from C. hominis, determined at 2.8 and 2.87 Å resolution, reveals that the interactions of residues Ile29, Thr58 and Cys113 in the active site of C. hominis DHFR provide a possible structural basis for the observed antifolate resistance. A comparison with the structure of human DHFR reveals active-site differences that may be exploited for the design of species-selective inhibitors.

[Mastitis revealing Churg-Strauss syndrome].

Science.gov (United States)

Dannepond, C; Le Fourn, E; de Muret, A; Ouldamer, L; Carmier, D; Machet, L

2014-01-01

Churg-Strauss syndrome often involves the skin, and this may sometimes reveal the disease. A 25-year-old woman was referred to a gynaecologist for inflammation of the right breast with breast discharge. Cytological analysis of the liquid showed numerous inflammatory cells, particularly polymorphonuclear eosinophils and neutrophils. Ultrasound examination of the breast was consistent with galactophoritis. CRP was normal, and hypereosinophilia was seen. The patient was subsequently referred to a dermatology unit. Skin examination revealed inflammation of the entire breast, which was painful, warm and erythematous; the border was oedematous with blisters. Necrotic lesions were also present on the thumbs and knees. Skin biopsy of the breast showed a dermal infiltrate with abundant infiltrate of polymorphonuclear eosinophils, including patchy necrosis and intraepidermal vesicles. Histological examination of a biopsy sample from a thumb revealed eosinophilic granuloma and leukocytoclastic vasculitis. The patient was also presenting asthma, pulmonary infiltrates and mononeuropathy at L3, consistent with Churg-Strauss syndrome. Breast involvement in Churg-Strauss syndrome is very rare (only one other case has been reported). This is the first case in which the breast condition revealed the disease. Cutaneous involvement of the breast is, however, also compatible with Wells' cellulitis. The lesions quickly disappeared with 1mg/kg/d oral prednisolone. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Adsorption Studies for Arsenic Removal Using Activated Moringa oleifera

Directory of Open Access Journals (Sweden)

T. Sumathi

2014-01-01

Full Text Available A new low cost adsorbent, activated Moringa oleifera has been developed for aqueous arsenic removal. Batch experiments were revealed that As removal was up to 71.3% using activated Moringa oleifera. Kinetics studies revealed that Langmuir isotherm was followed with a better correlation than the Freundlich isotherm. The thermodynamic parameters such as ΔH, ΔS, and ΔG were computed from the experimental data. These values show that the adsorption is endothermic and spontaneous in nature. Thus, this recently developed cost-effective novel biosorbent, activated Moringa oleifera can be used as household level to mitigate the arsenic problem.

Baseline brain activity changes in patients with clinically isolated syndrome revealed by resting-state functional MRI

Energy Technology Data Exchange (ETDEWEB)

Liu, Yaou; Duan, Yunyun; Liang, Peipeng; Jia, Xiuqin; Yu, Chunshui [Dept. of Radiology, Xuanwu Hospital, Capital Medical Univ., Beijing (China); Ye, Jing [Dept. of Neurology, Xuanwu Hospital, Capital Medical Univ., Beijing (China); Butzkueven, Helmut [Dept. of Medicine, Univ. of Melbourne, Melbourne (Australia); Dong, Huiqing [Dept. of Neurology, Xuanwu Hospital, Capital Medical Univ., Beijing (China); Li, Kuncheng [Dept. of Radiology, Xuanwu Hospital, Capital Medical Univ., Beijing (China); Beijing Key Laboratory of MRI and Brain Informatics, Beijing (China)], E-mail: likuncheng1955@yahoo.com.cn

2012-11-15

Background A clinically isolated syndrome (CIS) is the first manifestation of multiple sclerosis (MS). Previous task-related functional MRI studies demonstrate functional reorganization in patients with CIS. Purpose To assess baseline brain activity changes in patients with CIS by using the technique of regional amplitude of low frequency fluctuation (ALFF) as an index in resting-state fMRI. Material and Methods Resting-state fMRIs data acquired from 37 patients with CIS and 37 age- and sex-matched normal controls were compared to investigate ALFF differences. The relationships between ALFF in regions with significant group differences and the EDSS (Expanded Disability Status Scale), disease duration, and T2 lesion volume (T2LV) were further explored. Results Patients with CIS had significantly decreased ALFF in the right anterior cingulate cortex, right caudate, right lingual gyrus, and right cuneus (P < 0.05 corrected for multiple comparisons using Monte Carlo simulation) compared to normal controls, while no significantly increased ALFF were observed in CIS. No significant correlation was found between the EDSS, disease duration, T2LV, and ALFF in regions with significant group differences. Conclusion In patients with CIS, resting-state fMRI demonstrates decreased activity in several brain regions. These results are in contrast to patients with established MS, in whom ALFF demonstrates several regions of increased activity. It is possible that this shift from decreased activity in CIS to increased activity in MS could reflect the dynamics of cortical reorganization.

Antimalarial Activity of Azadipeptide Nitriles

OpenAIRE

Löser, Reik; Gut, Jiri; Rosenthal, Philip J.; Frizler, Maxim; Gütschow, Michael; Andrews, Katherine T.

2009-01-01

Azadipeptide nitriles – novel cysteine protease inhibitors – display structure-dependent antimalarial activity against both chloroquine-sensitive and chloroquine-resistant lines of cultured Plasmodium falciparum malaria parasites. Inhibition of parasite’s haemoglobin-degrading cysteine proteases was also investigated, revealing the azadipeptide nitriles as potent inhibitors of falcipain-2 and -3. A correlation between the cysteine protease-inhibiting activity and the antimalarial potential of...

Uncoupling of dynamin polymerization and GTPase activity revealed by the conformation-specific nanobody dynab.

Science.gov (United States)

Galli, Valentina; Sebastian, Rafael; Moutel, Sandrine; Ecard, Jason; Perez, Franck; Roux, Aurélien

2017-10-12

Dynamin is a large GTPase that forms a helical collar at the neck of endocytic pits, and catalyzes membrane fission (Schmid and Frolov, 2011; Ferguson and De Camilli, 2012). Dynamin fission reaction is strictly dependent on GTP hydrolysis, but how fission is mediated is still debated (Antonny et al., 2016): GTP energy could be spent in membrane constriction required for fission, or in disassembly of the dynamin polymer to trigger fission. To follow dynamin GTP hydrolysis at endocytic pits, we generated a conformation-specific nanobody called dynab, that binds preferentially to the GTP hydrolytic state of dynamin-1. Dynab allowed us to follow the GTPase activity of dynamin-1 in real-time. We show that in fibroblasts, dynamin GTP hydrolysis occurs as stochastic bursts, which are randomly distributed relatively to the peak of dynamin assembly. Thus, dynamin disassembly is not coupled to GTPase activity, supporting that the GTP energy is primarily spent in constriction.

Chain networking revealed by molecular dynamics simulation

Science.gov (United States)

Zheng, Yexin; Tsige, Mesfin; Wang, Shi-Qing

Based on Kremer-Grest model for entangled polymer melts, we demonstrate how the response of a polymer glass depends critically on the chain length. After quenching two melts of very different chain lengths (350 beads per chain and 30 beads per chain) into deeply glassy states, we subject them to uniaxial extension. Our MD simulations show that the glass of long chains undergoes stable necking after yielding whereas the system of short chains is unable to neck and breaks up after strain localization. During ductile extension of the polymer glass made of long chain significant chain tension builds up in the load-bearing strands (LBSs). Further analysis is expected to reveal evidence of activation of the primary structure during post-yield extension. These results lend support to the recent molecular model 1 and are the simulations to demonstrate the role of chain networking. This work is supported, in part, by a NSF Grant (DMR-EAGER-1444859)

Flow cytometric analysis reveals the high levels of platelet activation parameters in circulation of multiple sclerosis patients.

Science.gov (United States)

Morel, Agnieszka; Rywaniak, Joanna; Bijak, Michał; Miller, Elżbieta; Niwald, Marta; Saluk, Joanna

2017-06-01

The epidemiological studies confirm an increased risk of cardiovascular disease in multiple sclerosis, especially prothrombotic events directly associated with abnormal platelet activity. The aim of our study was to investigate the level of blood platelet activation in the circulation of patients with chronic phase of multiple sclerosis (SP MS) and their reactivity in response to typical platelets' physiological agonists. We examined 85 SP MS patients diagnosed according to the revised McDonald's criteria and 50 healthy volunteers as a control group. The platelet activation and reactivity were assessed using flow cytometry analysis of the following: P-selectin expression (CD62P), activation of GP IIb/IIIa complex (PAC-1 binding), and formation of platelet microparticles (PMPs) and platelet aggregates (PA) in agonist-stimulated (ADP, collagen) and unstimulated whole blood samples. Furthermore, we measured the level of soluble P-selectin (sP-selectin) in plasma using ELISA method, to evaluate the in vivo level of platelet activation, both in healthy and SP MS subjects. We found a statistically significant increase in P-selectin expression, GP IIb/IIIa activation, and formation of PMPs and PA, as well as in unstimulated and agonist-stimulated (ADP, collagen) platelets in whole blood samples from patients with SP MS in comparison to the control group. We also determined the higher sP-selectin level in plasma of SP MS subjects than in the control group. Based on the obtained results, we might conclude that during the course of SP MS platelets are chronically activated and display hyperreactivity to physiological agonists, such as ADP or collagen.

Adsorption Studies for Arsenic Removal Using Activated Moringa oleifera

OpenAIRE

T. Sumathi; G. Alagumuthu

2014-01-01

A new low cost adsorbent, activated Moringa oleifera has been developed for aqueous arsenic removal. Batch experiments were revealed that As removal was up to 71.3% using activated Moringa oleifera. Kinetics studies revealed that Langmuir isotherm was followed with a better correlation than the Freundlich isotherm. The thermodynamic parameters such as ΔH, ΔS, and ΔG were computed from the experimental data. These values show that the adsorption is endothermic and spontaneous in nature. Thus, ...

Heterogeneous adsorption behavior of landfill leachate on granular activated carbon revealed by fluorescence excitation emission matrix (EEM)-parallel factor analysis (PARAFAC).

Science.gov (United States)

Lee, Sonmin; Hur, Jin

2016-04-01

Heterogeneous adsorption behavior of landfill leachate on granular activated carbon (GAC) was investigated by fluorescence excitation-emission matrix (EEM) combined with parallel factor analysis (PARAFAC). The equilibrium adsorption of two leachates on GAC was well described by simple Langmuir and Freundlich isotherm models. More nonlinear isotherm and a slower adsorption rate were found for the leachate with the higher values of specific UV absorbance and humification index, suggesting that the leachate containing more aromatic content and condensed structures might have less accessible sites of GAC surface and a lower degree of diffusive adsorption. Such differences in the adsorption behavior were found even within the bulk leachate as revealed by the dissimilarity in the isotherm and kinetic model parameters between two identified PARAFAC components. For both leachates, terrestrial humic-like fluorescence (C1) component, which is likely associated with relatively large sized and condensed aromatic structures, exhibited a higher isotherm nonlinearity and a slower kinetic rate for GAC adsorption than microbial humic-like (C2) component. Our results were consistent with size exclusion effects, a well-known GAC adsorption mechanism. This study demonstrated the promising benefit of using EEM-PARAFAC for GAC adsorption processes of landfill leachate through fast monitoring of the influent and treated leachate, which can provide valuable information on optimizing treatment processes and predicting further environmental impacts of the treated effluent. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dual activation of pathways regulated by steroid receptors and peptide growth factors in primary prostate cancer revealed by Factor Analysis of microarray data

Directory of Open Access Journals (Sweden)

Fernandez Pedro L

2005-08-01

Full Text Available Abstract Background We use an approach based on Factor Analysis to analyze datasets generated for transcriptional profiling. The method groups samples into biologically relevant categories, and enables the identification of genes and pathways most significantly associated to each phenotypic group, while allowing for the participation of a given gene in more than one cluster. Genes assigned to each cluster are used for the detection of pathways predominantly activated in that cluster by finding statistically significant associated GO terms. We tested the approach with a published dataset of microarray experiments in yeast. Upon validation with the yeast dataset, we applied the technique to a prostate cancer dataset. Results Two major pathways are shown to be activated in organ-confined, non-metastatic prostate cancer: those regulated by the androgen receptor and by receptor tyrosine kinases. A number of gene markers (HER3, IQGAP2 and POR1 highlighted by the software and related to the later pathway have been validated experimentally a posteriori on independent samples. Conclusion Using a new microarray analysis tool followed by a posteriori experimental validation of the results, we have confirmed several putative markers of malignancy associated with peptide growth factor signalling in prostate cancer and revealed others, most notably ERRB3 (HER3. Our study suggest that, in primary prostate cancer, HER3, together or not with HER4, rather than in receptor complexes involving HER2, could play an important role in the biology of these tumors. These results provide new evidence for the role of receptor tyrosine kinases in the establishment and progression of prostate cancer.

Decomposition of BOLD Activity into Tuned and Untuned Components Reveals Cohabitation of Stimulus and Choice Information in V1

Directory of Open Access Journals (Sweden)

Kyoung Whan Choe

2012-10-01

Full Text Available Recent studies on V1 report top-down modulation of input-driven responses of sensory neurons, implying that exogenous sensory drives and endogenous top-down drives jointly determine V1 responses. By measuring fMRI responses in conjunction with a classification task on ambiguous ring stimuli, we sought to understand how V1 carries out its encoding operation on afferent currents while being adaptively modulated by top-down currents associated with perceptual tasks. Population activity of V1, as in its raw eccentricity profiles, failed to resolve the threshold differences between the ring stimuli due to large moment-to-moment fluctuations. The analysis of variance indicated that stimulus-evoked responses explain only one-fifth of the total variance and fMRI responses were highly correlated among eccentricity-bins, implying that a substantial fraction of V1 responses fluctuate as a whole. This led us to decompose the raw fMRI responses into untuned and tuned components: average response across eccentricity-bins and residual responses from the average, respectively, the former varying only in time and the latter varying in both space and time. The tuned responses revealed the veridical encoding operation of V1 by readily distinguishing between the ring stimuli, which was impossible with the raw fMRI responses. In contrast, the untuned were correlated with two major aspects of choice behavior—inter-trial variability in response time and inter-subject variability in response bias. We propose that this cohabitation of stimulus and choice information in V1 indicates the presence of top-down exertion of gain modulation on the early processing stage by the high-tier stage that accumulates evidence for perceptual choices.

Principles of Chromosome Architecture Revealed by Hi-C.

Science.gov (United States)

Eagen, Kyle P

2018-06-01

Chromosomes are folded and compacted in interphase nuclei, but the molecular basis of this folding is poorly understood. Chromosome conformation capture methods, such as Hi-C, combine chemical crosslinking of chromatin with fragmentation, DNA ligation, and high-throughput DNA sequencing to detect neighboring loci genome-wide. Hi-C has revealed the segregation of chromatin into active and inactive compartments and the folding of DNA into self-associating domains and loops. Depletion of CTCF, cohesin, or cohesin-associated proteins was recently shown to affect the majority of domains and loops in a manner that is consistent with a model of DNA folding through extrusion of chromatin loops. Compartmentation was not dependent on CTCF or cohesin. Hi-C contact maps represent the superimposition of CTCF/cohesin-dependent and -independent folding states. Copyright © 2018 Elsevier Ltd. All rights reserved.

Biosensor reveals multiple sources for mitochondrial NAD⁺.

Science.gov (United States)

Cambronne, Xiaolu A; Stewart, Melissa L; Kim, DongHo; Jones-Brunette, Amber M; Morgan, Rory K; Farrens, David L; Cohen, Michael S; Goodman, Richard H

2016-06-17

Nicotinamide adenine dinucleotide (NAD(+)) is an essential substrate for sirtuins and poly(adenosine diphosphate-ribose) polymerases (PARPs), which are NAD(+)-consuming enzymes localized in the nucleus, cytosol, and mitochondria. Fluctuations in NAD(+) concentrations within these subcellular compartments are thought to regulate the activity of NAD(+)-consuming enzymes; however, the challenge in measuring compartmentalized NAD(+) in cells has precluded direct evidence for this type of regulation. We describe the development of a genetically encoded fluorescent biosensor for directly monitoring free NAD(+) concentrations in subcellular compartments. We found that the concentrations of free NAD(+) in the nucleus, cytoplasm, and mitochondria approximate the Michaelis constants for sirtuins and PARPs in their respective compartments. Systematic depletion of enzymes that catalyze the final step of NAD(+) biosynthesis revealed cell-specific mechanisms for maintaining mitochondrial NAD(+) concentrations. Copyright © 2016, American Association for the Advancement of Science.

Systematically Altering Bacterial SOS Activity under Stress Reveals Therapeutic Strategies for Potentiating Antibiotics.

Science.gov (United States)

Mo, Charlie Y; Manning, Sara A; Roggiani, Manuela; Culyba, Matthew J; Samuels, Amanda N; Sniegowski, Paul D; Goulian, Mark; Kohli, Rahul M

2016-01-01

The bacterial SOS response is a DNA damage repair network that is strongly implicated in both survival and acquired drug resistance under antimicrobial stress. The two SOS regulators, LexA and RecA, have therefore emerged as potential targets for adjuvant therapies aimed at combating resistance, although many open questions remain. For example, it is not well understood whether SOS hyperactivation is a viable therapeutic approach or whether LexA or RecA is a better target. Furthermore, it is important to determine which antimicrobials could serve as the best treatment partners with SOS-targeting adjuvants. Here we derived Escherichia coli strains that have mutations in either lexA or recA genes in order to cover the full spectrum of possible SOS activity levels. We then systematically analyzed a wide range of antimicrobials by comparing the mean inhibitory concentrations (MICs) and induced mutation rates for each drug-strain combination. We first show that significant changes in MICs are largely confined to DNA-damaging antibiotics, with strains containing a constitutively repressed SOS response impacted to a greater extent than hyperactivated strains. Second, antibiotic-induced mutation rates were suppressed when SOS activity was reduced, and this trend was observed across a wider spectrum of antibiotics. Finally, perturbing either LexA or RecA proved to be equally viable strategies for targeting the SOS response. Our work provides support for multiple adjuvant strategies, while also suggesting that the combination of an SOS inhibitor with a DNA-damaging antibiotic could offer the best potential for lowering MICs and decreasing acquired drug resistance. IMPORTANCE Our antibiotic arsenal is becoming depleted, in part, because bacteria have the ability to rapidly adapt and acquire resistance to our best agents. The SOS pathway, a widely conserved DNA damage stress response in bacteria, is activated by many antibiotics and has been shown to play central role in

Analysis of morphine responses in mice reveals a QTL on Chromosome 7 [version 1; referees: 2 approved

Directory of Open Access Journals (Sweden)

Wim E. Crusio

2016-09-01

Full Text Available In this study we identified a quantitative trait locus (QTL on mouse Chromosome 7 associated with locomotor activity and rearing post morphine treatment. This QTL was revealed after correcting for the effects of another QTL peak on Chromosome 10 using composite interval mapping. The positional candidate genes are Syt9 and Ppfibp2. Several other genes within the interval are linked to neural processes, locomotor activity, and the defensive response to harmful stimuli.

Analysis of morphine responses in mice reveals a QTL on Chromosome 7 [version 2; referees: 2 approved

Directory of Open Access Journals (Sweden)

Wim E. Crusio

2016-10-01

Full Text Available In this study we identified a quantitative trait locus (QTL on mouse Chromosome 7 associated with locomotor activity and rearing post morphine treatment. This QTL was revealed after correcting for the effects of another QTL peak on Chromosome 10 using composite interval mapping. The positional candidate genes are Syt9 and Ppfibp2. Several other genes within the interval are linked to neural processes, locomotor activity, and the defensive response to harmful stimuli.

Neural Activity Reveals Preferences Without Choices

Science.gov (United States)

Smith, Alec; Bernheim, B. Douglas; Camerer, Colin

2014-01-01

We investigate the feasibility of inferring the choices people would make (if given the opportunity) based on their neural responses to the pertinent prospects when they are not engaged in actual decision making. The ability to make such inferences is of potential value when choice data are unavailable, or limited in ways that render standard methods of estimating choice mappings problematic. We formulate prediction models relating choices to “non-choice” neural responses and use them to predict out-of-sample choices for new items and for new groups of individuals. The predictions are sufficiently accurate to establish the feasibility of our approach. PMID:25729468

Transcriptomic Analysis Reveals Selective Metabolic Adaptation of Streptococcus suis to Porcine Blood and Cerebrospinal Fluid

Directory of Open Access Journals (Sweden)

Anna Koczula

2017-02-01

Full Text Available Streptococcus suis is a zoonotic pathogen that can cause severe pathologies such as septicemia and meningitis in its natural porcine host as well as in humans. Establishment of disease requires not only virulence of the infecting strain but also an appropriate metabolic activity of the pathogen in its host environment. However, it is yet largely unknown how the streptococcal metabolism adapts to the different host niches encountered during infection. Our previous isotopologue profiling studies on S. suis grown in porcine blood and cerebrospinal fluid (CSF revealed conserved activities of central carbon metabolism in both body fluids. On the other hand, they suggested differences in the de novo amino acid biosynthesis. This prompted us to further dissect S. suis adaptation to porcine blood and CSF by RNA deep sequencing (RNA-seq. In blood, the majority of differentially expressed genes were associated with transport of alternative carbohydrate sources and the carbohydrate metabolism (pentose phosphate pathway, glycogen metabolism. In CSF, predominantly genes involved in the biosynthesis of branched-chain and aromatic amino acids were differentially expressed. Especially, isoleucine biosynthesis seems to be of major importance for S. suis in CSF because several related biosynthetic genes were more highly expressed. In conclusion, our data revealed niche-specific metabolic gene activity which emphasizes a selective adaptation of S. suis to host environments.

Discrete nuclear structures in actively growing neuroblastoma cells are revealed by antibodies raised against phosphorylated neurofilament proteins

Directory of Open Access Journals (Sweden)

Raabe Timothy D

2003-04-01

Full Text Available Abstract Background Nuclear objects that have in common the property of being recognized by monoclonal antibodies specific for phosphoprotein epitopes and cytoplasmic intermediate filaments (in particular, SMI-31 and RT-97 have been reported in glial and neuronal cells, in situ and in vitro. Since neurofilament and glial filaments are generally considered to be restricted to the cytoplasm, we were interested in exploring the identity of the structures labeled in the nucleus as well as the conditions under which they could be found there. Results Using confocal microscopy and western analysis techniques, we determined 1 the immunolabeled structures are truly within the nucleus; 2 the phosphoepitope labeled by SMI-31 and RT-97 is not specific to neurofilaments (NFs and it can be identified on other intermediate filament proteins (IFs in other cell types; and 3 there is a close relationship between DNA synthesis and the amount of nuclear staining by these antibodies thought to be specific for cytoplasmic proteins. Searches of protein data bases for putative phosphorylation motifs revealed that lamins, NF-H, and GFAP each contain a single tyrosine phosphorylation motif with nearly identical amino acid sequence. Conclusion We therefore suggest that this sequence may be the epitope recognized by SMI-31 and RT-97 mABs, and that the nuclear structures previously reported and shown here are likely phosphorylated lamin intermediate filaments, while the cytoplasmic labeling revealed by the same mABs indicates phosphorylated NFs in neurons or GFAP in glia.

Gene expression profiling in equine polysaccharide storage myopathy revealed inflammation, glycogenesis inhibition, hypoxia and mitochondrial dysfunctions

Directory of Open Access Journals (Sweden)

Benech Philippe

2009-08-01

Full Text Available Abstract Background Several cases of myopathies have been observed in the horse Norman Cob breed. Muscle histology examinations revealed that some families suffer from a polysaccharide storage myopathy (PSSM. It is assumed that a gene expression signature related to PSSM should be observed at the transcriptional level because the glycogen storage disease could also be linked to other dysfunctions in gene regulation. Thus, the functional genomic approach could be conducted in order to provide new knowledge about the metabolic disorders related to PSSM. We propose exploring the PSSM muscle fiber metabolic disorders by measuring gene expression in relationship with the histological phenotype. Results Genotypying analysis of GYS1 mutation revealed 2 homozygous (AA and 5 heterozygous (GA PSSM horses. In the PSSM muscles, histological data revealed PAS positive amylase resistant abnormal polysaccharides, inflammation, necrosis, and lipomatosis and active regeneration of fibers. Ultrastructural evaluation revealed a decrease of mitochondrial number and structural disorders. Extensive accumulation of an abnormal polysaccharide displaced and partially replaced mitochondria and myofibrils. The severity of the disease was higher in the two homozygous PSSM horses. Gene expression analysis revealed 129 genes significantly modulated (p Conclusion The main disorders observed in PSSM muscles could be related to mitochondrial dysfunctions, glycogenesis inhibition and the chronic hypoxia of the PSSM muscles.

Quantitative Proteomics of the Tonoplast Reveals a Role for Glycolytic Enzymes in Salt Tolerance[C][W

Science.gov (United States)

Barkla, Bronwyn J.; Vera-Estrella, Rosario; Hernández-Coronado, Marcela; Pantoja, Omar

2009-01-01

To examine the role of the tonoplast in plant salt tolerance and identify proteins involved in the regulation of transporters for vacuolar Na+ sequestration, we exploited a targeted quantitative proteomics approach. Two-dimensional differential in-gel electrophoresis analysis of free flow zonal electrophoresis separated tonoplast fractions from control, and salt-treated Mesembryanthemum crystallinum plants revealed the membrane association of glycolytic enzymes aldolase and enolase, along with subunits of the vacuolar H+-ATPase V-ATPase. Protein blot analysis confirmed coordinated salt regulation of these proteins, and chaotrope treatment indicated a strong tonoplast association. Reciprocal coimmunoprecipitation studies revealed that the glycolytic enzymes interacted with the V-ATPase subunit B VHA-B, and aldolase was shown to stimulate V-ATPase activity in vitro by increasing the affinity for ATP. To investigate a physiological role for this association, the Arabidopsis thaliana cytoplasmic enolase mutant, los2, was characterized. These plants were salt sensitive, and there was a specific reduction in enolase abundance in the tonoplast from salt-treated plants. Moreover, tonoplast isolated from mutant plants showed an impaired ability for aldolase stimulation of V-ATPase hydrolytic activity. The association of glycolytic proteins with the tonoplast may not only channel ATP to the V-ATPase, but also directly upregulate H+-pump activity. PMID:20028841

Changes in Metabolically Active Bacterial Community during Rumen Development, and Their Alteration by Rhubarb Root Powder Revealed by 16S rRNA Amplicon Sequencing.

Science.gov (United States)

Wang, Zuo; Elekwachi, Chijioke; Jiao, Jinzhen; Wang, Min; Tang, Shaoxun; Zhou, Chuanshe; Tan, Zhiliang; Forster, Robert J

2017-01-01

The objective of this present study was to explore the initial establishment of metabolically active bacteria and subsequent evolution in four fractions: rumen solid-phase (RS), liquid-phase (RL), protozoa-associated (RP), and epithelium-associated (RE) through early weaning and supplementing rhubarb root powder in 7 different age groups (1, 10, 20, 38, 41, 50, and 60 d) during rumen development. Results of the 16S rRNA sequencing based on RNA isolated from the four fractions revealed that the potentially active bacterial microbiota in four fractions were dominated by the phyla Proteobacteria, Firmicutes , and Bacteroidetes regardless of different ages. An age-dependent increment of Chao 1 richness was observed in the fractions of RL and RE. The principal coordinate analysis (PCoA) indicated that samples in four fractions all clustered based on different age groups, and the structure of the bacterial community in RE was distinct from those in other three fractions. The abundances of Proteobacteria decreased significantly ( P < 0.05) with age, while increases in the abundances of Firmicutes and Bacteroidetes were noted. At the genus level, the abundance of the predominant genus Mannheimia in the Proteobacteria phylum decreased significantly ( P < 0.05) after 1 d, while the genera Quinella, Prevotella, Fretibacterium, Ruminococcus, Lachnospiraceae NK3A20 group , and Atopobium underwent different manners of increases and dominated the bacterial microbiota across four fractions. Variations of the distributions of some specific bacterial genera across fractions were observed, and supplementation of rhubarb affected the relative abundance of various genera of bacteria.

Puerto Rico Revealed Preference Survey Data 2004

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Revealed preference models provide insights into recreational angler behavior and the economic value of recreational fishing trips. Revealed preference data is...

Comparative analysis of fungal genomes reveals different plant cell wall degrading capacity in fungi

Science.gov (United States)

2013-01-01

Background Fungi produce a variety of carbohydrate activity enzymes (CAZymes) for the degradation of plant polysaccharide materials to facilitate infection and/or gain nutrition. Identifying and comparing CAZymes from fungi with different nutritional modes or infection mechanisms may provide information for better understanding of their life styles and infection models. To date, over hundreds of fungal genomes are publicly available. However, a systematic comparative analysis of fungal CAZymes across the entire fungal kingdom has not been reported. Results In this study, we systemically identified glycoside hydrolases (GHs), polysaccharide lyases (PLs), carbohydrate esterases (CEs), and glycosyltransferases (GTs) as well as carbohydrate-binding modules (CBMs) in the predicted proteomes of 103 representative fungi from Ascomycota, Basidiomycota, Chytridiomycota, and Zygomycota. Comparative analysis of these CAZymes that play major roles in plant polysaccharide degradation revealed that fungi exhibit tremendous diversity in the number and variety of CAZymes. Among them, some families of GHs and CEs are the most prevalent CAZymes that are distributed in all of the fungi analyzed. Importantly, cellulases of some GH families are present in fungi that are not known to have cellulose-degrading ability. In addition, our results also showed that in general, plant pathogenic fungi have the highest number of CAZymes. Biotrophic fungi tend to have fewer CAZymes than necrotrophic and hemibiotrophic fungi. Pathogens of dicots often contain more pectinases than fungi infecting monocots. Interestingly, besides yeasts, many saprophytic fungi that are highly active in degrading plant biomass contain fewer CAZymes than plant pathogenic fungi. Furthermore, analysis of the gene expression profile of the wheat scab fungus Fusarium graminearum revealed that most of the CAZyme genes related to cell wall degradation were up-regulated during plant infection. Phylogenetic analysis also

Production and characterization of granular activated carbon from activated sludge

Directory of Open Access Journals (Sweden)

Z. Al-Qodah

2009-03-01

Full Text Available In this study, activated sludge was used as a precursor to prepare activated carbon using sulfuric acid as a chemical activation agent. The effect of preparation conditions on the produced activated carbon characteristics as an adsorbent was investigated. The results indicate that the produced activated carbon has a highly porous structure and a specific surface area of 580 m²/g. The FT-IR analysis depicts the presence of a variety of functional groups which explain its improved adsorption behavior against pesticides. The XRD analysis reveals that the produced activated carbon has low content of inorganic constituents compared with the precursor. The adsorption isotherm data were fitted to three adsorption isotherm models and found to closely fit the BET model with R² equal 0.948 at pH 3, indicating a multilayer of pesticide adsorption. The maximum loading capacity of the produced activated carbon was 110 mg pesticides/g adsorbent and was obtained at this pH value. This maximum loading was found experimentally to steeply decrease as the solution pH increases. The obtained results show that activated sludge is a promising low cost precursor for the production of activated carbon.

The 'revealed preferences' theory: Assumptions and conjectures

International Nuclear Information System (INIS)

Green, C.H.

1983-01-01

Being kind of intuitive psychology the 'Revealed-Preferences'- theory based approaches towards determining the acceptable risks are a useful method for the generation of hypotheses. In view of the fact that reliability engineering develops faster than methods for the determination of reliability aims the Revealed-Preferences approach is a necessary preliminary help. Some of the assumptions on which the 'Revealed-Preferences' theory is based will be identified and analysed and afterwards compared with experimentally obtained results. (orig./DG) [de

A High-Resolution Crystal Structure of a Psychrohalophilic α-Carbonic Anhydrase from Photobacterium profundum Reveals a Unique Dimer Interface.

Directory of Open Access Journals (Sweden)

Vijayakumar Somalinga

Full Text Available Bacterial α-carbonic anhydrases (α-CA are zinc containing metalloenzymes that catalyze the rapid interconversion of CO2 to bicarbonate and a proton. We report the first crystal structure of a pyschrohalophilic α-CA from a deep-sea bacterium, Photobacterium profundum. Size exclusion chromatography of the purified P. profundum α-CA (PprCA reveals that the protein is a heterogeneous mix of monomers and dimers. Furthermore, an "in-gel" carbonic anhydrase activity assay, also known as protonography, revealed two distinct bands corresponding to monomeric and dimeric forms of PprCA that are catalytically active. The crystal structure of PprCA was determined in its native form and reveals a highly conserved "knot-topology" that is characteristic of α-CA's. Similar to other bacterial α-CA's, PprCA also crystallized as a dimer. Furthermore, dimer interface analysis revealed the presence of a chloride ion (Cl- in the interface which is unique to PprCA and has not been observed in any other α-CA's characterized so far. Molecular dynamics simulation and chloride ion occupancy analysis shows 100% occupancy for the Cl- ion in the dimer interface. Zinc coordinating triple histidine residues, substrate binding hydrophobic patch residues, and the hydrophilic proton wire residues are highly conserved in PprCA and are identical to other well-studied α-CA's.

Structure of the first representative of Pfam family PF04016 (DUF364) reveals enolase and Rossmann-like folds that combine to form a unique active site with a possible role in heavy-metal chelation

International Nuclear Information System (INIS)

Miller, Mitchell D.; Aravind, L.; Bakolitsa, Constantina; Rife, Christopher L.; Carlton, Dennis; Abdubek, Polat; Astakhova, Tamara; Axelrod, Herbert L.; Chiu, Hsiu-Ju; Clayton, Thomas; Deller, Marc C.; Duan, Lian; Feuerhelm, Julie; Grant, Joanna C.; Han, Gye Won; Jaroszewski, Lukasz; Jin, Kevin K.; Klock, Heath E.; Knuth, Mark W.; Kozbial, Piotr; Krishna, S. Sri; Kumar, Abhinav; Marciano, David; McMullan, Daniel; Morse, Andrew T.; Nigoghossian, Edward; Okach, Linda; Reyes, Ron; Bedem, Henry van den; Weekes, Dana; Xu, Qingping; Hodgson, Keith O.; Wooley, John; Elsliger, Marc-André; Deacon, Ashley M.; Godzik, Adam; Lesley, Scott A.; Wilson, Ian A.

2010-01-01

The crystal structure of the first representative of DUF364 family reveals a combination of enolase N-terminal-like and C-terminal Rossmann-like folds. Analysis of the interdomain cleft combined with sequence and genome context conservation among homologs, suggests a unique catalytic site likely involved in the synthesis of a flavin or pterin derivative. The crystal structure of Dhaf4260 from Desulfitobacterium hafniense DCB-2 was determined by single-wavelength anomalous diffraction (SAD) to a resolution of 2.01 Å using the semi-automated high-throughput pipeline of the Joint Center for Structural Genomics (JCSG) as part of the NIGMS Protein Structure Initiative (PSI). This protein structure is the first representative of the PF04016 (DUF364) Pfam family and reveals a novel combination of two well known domains (an enolase N-terminal-like fold followed by a Rossmann-like domain). Structural and bioinformatic analyses reveal partial similarities to Rossmann-like methyltransferases, with residues from the enolase-like fold combining to form a unique active site that is likely to be involved in the condensation or hydrolysis of molecules implicated in the synthesis of flavins, pterins or other siderophores. The genome context of Dhaf4260 and homologs additionally supports a role in heavy-metal chelation

Proteomic Analysis Reveals a Role for Bcl2-associated Athanogene 3 and Major Vault Protein in Resistance to Apoptosis in Senescent Cells by Regulating ERK1/2 Activation*

Science.gov (United States)

Pasillas, Martina P.; Shields, Sarah; Reilly, Rebecca; Strnadel, Jan; Behl, Christian; Park, Robin; Yates, John R.; Klemke, Richard; Gonias, Steven L.; Coppinger, Judith A.

2015-01-01

Senescence is a prominent solid tumor response to therapy in which cells avoid apoptosis and instead enter into prolonged cell cycle arrest. We applied a quantitative proteomics screen to identify signals that lead to therapy-induced senescence and discovered that Bcl2-associated athanogene 3 (Bag3) is up-regulated after adriamycin treatment in MCF7 cells. Bag3 is a member of the BAG family of co-chaperones that interacts with Hsp70. Bag3 also regulates major cell-signaling pathways. Mass spectrometry analysis of the Bag3 Complex revealed a novel interaction between Bag3 and Major Vault Protein (MVP). Silencing of Bag3 or MVP shifts the cellular response to adriamycin to favor apoptosis. We demonstrate that Bag3 and MVP contribute to apoptosis resistance in therapy-induced senescence by increasing the level of activation of extracellular signal-regulated kinase1/2 (ERK1/2). Silencing of either Bag3 or MVP decreased ERK1/2 activation and promoted apoptosis in adriamycin-treated cells. An increase in nuclear accumulation of MVP is observed during therapy-induced senescence and the shift in MVP subcellular localization is Bag3-dependent. We propose a model in which Bag3 binds to MVP and facilitates MVP accumulation in the nucleus, which sustains ERK1/2 activation. We confirmed that silencing of Bag3 or MVP shifts the response toward apoptosis and regulates ERK1/2 activation in a panel of diverse breast cancer cell lines. This study highlights Bag3-MVP as an important complex that regulates a potent prosurvival signaling pathway and contributes to chemotherapy resistance in breast cancer. PMID:24997994

Attempting to be active: Self-efficacy and barrier limitation differentiate activity levels of working mothers.

Science.gov (United States)

Gierc, Madelaine; Locke, Sean; Jung, Mary; Brawley, Lawrence

2016-07-01

Working mothers are less physically active than working women without children and mothers who do not work. The purpose of this study was to examine concurrent self-regulatory efficacy and barriers to physical activity in a sample of working mothers. Women completed a mixed-methods survey which included measures of physical activity, concurrent self-regulatory efficacy, and barriers. Sufficiently active women experienced significantly greater concurrent self-regulatory efficacy and significantly less barrier limitation and frequency. No significant group differences were found for age, domestic duties performed, and children's extracurricular activities. Thematic analysis of barriers revealed six themes of common and unique factors, including limited time and family activities. © The Author(s) 2014.

Adenosine-deaminase (ADA activity in Psoriasis (A Preliminary Study

Directory of Open Access Journals (Sweden)

S D Chaudhry

1988-01-01

Full Text Available Study of adenosine-deaminase activity ′in 23 patients hav-mg psoriasis compared with an equal number of healthy controls revealed significantly high ADA-activity in the psotiatic patients.

Functional and evolutionary characterization of Ohr proteins in eukaryotes reveals many active homologs among pathogenic fungi.

Science.gov (United States)

Meireles, D A; Domingos, R M; Gaiarsa, J W; Ragnoni, E G; Bannitz-Fernandes, R; da Silva Neto, J F; de Souza, R F; Netto, L E S

2017-08-01

Ohr and OsmC proteins comprise two subfamilies within a large group of proteins that display Cys-based, thiol dependent peroxidase activity. These proteins were previously thought to be restricted to prokaryotes, but we show here, using iterated sequence searches, that Ohr/OsmC homologs are also present in 217 species of eukaryotes with a massive presence in Fungi (186 species). Many of these eukaryotic Ohr proteins possess an N-terminal extension that is predicted to target them to mitochondria. We obtained recombinant proteins for four eukaryotic members of the Ohr/OsmC family and three of them displayed lipoyl peroxidase activity. Further functional and biochemical characterization of the Ohr homologs from the ascomycete fungus Mycosphaerella fijiensis Mf_1 (MfOhr), the causative agent of Black Sigatoka disease in banana plants, was pursued. Similarly to what has been observed for the bacterial proteins, we found that: (i) the peroxidase activity of MfOhr was supported by DTT or dihydrolipoamide (dithiols), but not by β-mercaptoethanol or GSH (monothiols), even in large excess; (ii) MfOhr displayed preference for organic hydroperoxides (CuOOH and tBOOH) over hydrogen peroxide; (iii) MfOhr presented extraordinary reactivity towards linoleic acid hydroperoxides (k=3.18 (±2.13)×10 8 M -1 s -1 ). Both Cys 87 and Cys 154 were essential to the peroxidase activity, since single mutants for each Cys residue presented no activity and no formation of intramolecular disulfide bond upon treatment with hydroperoxides. The pK a value of the Cys p residue was determined as 5.7±0.1 by a monobromobimane alkylation method. Therefore, eukaryotic Ohr peroxidases share several biochemical features with prokaryotic orthologues and are preferentially located in mitochondria. Copyright © 2017. Published by Elsevier B.V.

Functional and evolutionary characterization of Ohr proteins in eukaryotes reveals many active homologs among pathogenic fungi

Directory of Open Access Journals (Sweden)

D.A. Meireles

2017-08-01

Full Text Available Ohr and OsmC proteins comprise two subfamilies within a large group of proteins that display Cys-based, thiol dependent peroxidase activity. These proteins were previously thought to be restricted to prokaryotes, but we show here, using iterated sequence searches, that Ohr/OsmC homologs are also present in 217 species of eukaryotes with a massive presence in Fungi (186 species. Many of these eukaryotic Ohr proteins possess an N-terminal extension that is predicted to target them to mitochondria. We obtained recombinant proteins for four eukaryotic members of the Ohr/OsmC family and three of them displayed lipoyl peroxidase activity. Further functional and biochemical characterization of the Ohr homologs from the ascomycete fungus Mycosphaerella fijiensis Mf_1 (MfOhr, the causative agent of Black Sigatoka disease in banana plants, was pursued. Similarly to what has been observed for the bacterial proteins, we found that: (i the peroxidase activity of MfOhr was supported by DTT or dihydrolipoamide (dithiols, but not by β-mercaptoethanol or GSH (monothiols, even in large excess; (ii MfOhr displayed preference for organic hydroperoxides (CuOOH and tBOOH over hydrogen peroxide; (iii MfOhr presented extraordinary reactivity towards linoleic acid hydroperoxides (k=3.18 (±2.13×108 M−1 s−1. Both Cys87 and Cys154 were essential to the peroxidase activity, since single mutants for each Cys residue presented no activity and no formation of intramolecular disulfide bond upon treatment with hydroperoxides. The pKa value of the Cysp residue was determined as 5.7±0.1 by a monobromobimane alkylation method. Therefore, eukaryotic Ohr peroxidases share several biochemical features with prokaryotic orthologues and are preferentially located in mitochondria. Keywords: Ohr/OsmC, Thiol-dependent peroxidases, Phylogeny

Quantitative Proteomics Reveals Temporal Proteomic Changes in Signaling Pathways during BV2 Mouse Microglial Cell Activation.

Science.gov (United States)

Woo, Jongmin; Han, Dohyun; Wang, Joseph Injae; Park, Joonho; Kim, Hyunsoo; Kim, Youngsoo

2017-09-01

The development of systematic proteomic quantification techniques in systems biology research has enabled one to perform an in-depth analysis of cellular systems. We have developed a systematic proteomic approach that encompasses the spectrum from global to targeted analysis on a single platform. We have applied this technique to an activated microglia cell system to examine changes in the intracellular and extracellular proteomes. Microglia become activated when their homeostatic microenvironment is disrupted. There are varying degrees of microglial activation, and we chose to focus on the proinflammatory reactive state that is induced by exposure to such stimuli as lipopolysaccharide (LPS) and interferon-gamma (IFN-γ). Using an improved shotgun proteomics approach, we identified 5497 proteins in the whole-cell proteome and 4938 proteins in the secretome that were associated with the activation of BV2 mouse microglia by LPS or IFN-γ. Of the differentially expressed proteins in stimulated microglia, we classified pathways that were related to immune-inflammatory responses and metabolism. Our label-free parallel reaction monitoring (PRM) approach made it possible to comprehensively measure the hyper-multiplex quantitative value of each protein by high-resolution mass spectrometry. Over 450 peptides that corresponded to pathway proteins and direct or indirect interactors via the STRING database were quantified by label-free PRM in a single run. Moreover, we performed a longitudinal quantification of secreted proteins during microglial activation, in which neurotoxic molecules that mediate neuronal cell loss in the brain are released. These data suggest that latent pathways that are associated with neurodegenerative diseases can be discovered by constructing and analyzing a pathway network model of proteins. Furthermore, this systematic quantification platform has tremendous potential for applications in large-scale targeted analyses. The proteomics data for

Volunteering as Students significant social activities

Directory of Open Access Journals (Sweden)

I. A. Zaitseva

2016-01-01

Full Text Available The article examines the involvement of students in volunteer activities, examines the organization of students volunteer activities and volunteer projects realization at the university. The potential of volunteerism as an effective mechanism for addressing the urgent social problems is revealed.Theauthorstudiesexperience of volunteer services organization the I.A. Bunin State University in Yelets.

Area-specific modulation of neural activation comparing escitalopram and citalopram revealed by pharmaco-fMRI: a randomized cross-over study.

Science.gov (United States)

Windischberger, Christian; Lanzenberger, Rupert; Holik, Alexander; Spindelegger, Christoph; Stein, Patrycja; Moser, Ulrike; Gerstl, Florian; Fink, Martin; Moser, Ewald; Kasper, Siegfried

2010-01-15

Area-specific and stimulation-dependent changes of human brain activation by selective serotonin reuptake inhibitors (SSRI) are an important issue for improved understanding of treatment mechanisms, given the frequent prescription of these drugs in depression and anxiety disorders. The aim of this neuroimaging study was to investigate differences in BOLD-signal caused by administration of the SSRIs escitalopram and citalopram using pharmacological functional magnetic resonance imaging (pharmaco-fMRI). Eighteen healthy subjects participated in a placebo-controlled, randomized, double-blind study in cross-over repeated measures design. Each volunteer performed facial emotional discrimination and a sensorimotor control paradigm during three scanning sessions. Citalopram (20 mg/d), escitalopram (10 mg/d) and placebo were administered for 10 days each with a drug-free period of at least 21 days. Significant pharmacological effects on BOLD-signal were found in the amygdala, medial frontal gyrus, parahippocampal, fusiform and middle temporal gyri. Post-hoc t-tests revealed decreased BOLD-signal in the right amygdala and left parahippocampal gyrus in both pharmacological conditions, compared to placebo. Escitalopram, compared to citalopram, induced a decrease of BOLD-signal in the medial frontal gyrus and an increase in the right fusiform and left parahippocampal gyri. Drug effects were concentrated in brain regions with dense serotonergic projections. Both escitalopram and citalopram attenuated BOLD-signal in the amygdala and parahippocampal cortex to emotionally significant stimuli compared to control stimuli. We believe that reduced reactivity in the medial frontal gyrus found for escitalopram compared to citalopram administration might explain the response differences between study drugs as demonstrated in previous clinical trials.

Animal-Borne Imaging Reveals Novel Insights into the Foraging Behaviors and Diel Activity of a Large-Bodied Apex Predator, the American Alligator (Alligator mississippiensis)

Science.gov (United States)

Nifong, James C.; Nifong, Rachel L.; Silliman, Brian R.; Lowers, Russell H.; Guillette, Louis J.; Ferguson, Jake M.; Welsh, Matthew; Abernathy, Kyler; Marshall, Greg

2014-01-01

Large-bodied, top- and apex predators (e.g., crocodilians, sharks, wolves, killer whales) can exert strong top-down effects within ecological communities through their interactions with prey. Due to inherent difficulties while studying the behavior of these often dangerous predatory species, relatively little is known regarding their feeding behaviors and activity patterns, information that is essential to understanding their role in regulating food web dynamics and ecological processes. Here we use animal-borne imaging systems (Crittercam) to study the foraging behavior and activity patterns of a cryptic, large-bodied predator, the American alligator (Alligator mississippiensis) in two estuaries of coastal Florida, USA. Using retrieved video data we examine the variation in foraging behaviors and activity patterns due to abiotic factors. We found the frequency of prey-attacks (mean = 0.49 prey attacks/hour) as well as the probability of prey-capture success (mean = 0.52 per attack) were significantly affected by time of day. Alligators attempted to capture prey most frequently during the night. Probability of prey-capture success per attack was highest during morning hours and sequentially lower during day, night, and sunset, respectively. Position in the water column also significantly affected prey-capture success, as individuals’ experienced two-fold greater success when attacking prey while submerged. These estimates are the first for wild adult American alligators and one of the few examples for any crocodilian species worldwide. More broadly, these results reveal that our understandings of crocodilian foraging behaviors are biased due to previous studies containing limited observations of cryptic and nocturnal foraging interactions. Our results can be used to inform greater understanding regarding the top-down effects of American alligators in estuarine food webs. Additionally, our results highlight the importance and power of using animal

Maintenance of neural activities in torpid Rhinolophus ferrumequinum bats revealed by 2D gel-based proteome analysis.

Science.gov (United States)

Yin, Qiuyuan; Zhang, Yijian; Dong, Dong; Lei, Ming; Zhang, Shuyi; Liao, Chen-Chung; Pan, Yi-Hsuan

2017-08-01

Bats are the only mammals capable of self-powered flying. Many bat species hibernate in winter. A reversible control of cerebral activities is critical for bats to accommodate a repeated torpor-arousal cycle during hibernation. Little is known about the molecular mechanisms that regulate neuronal activities in torpid bats. In this study, Rhinolophus ferrumequinum bat brain proteins were fractionated, and their abundance in active and torpid states was compared. Results of 2D gel-based proteomics showed that 38% of identified proteins with a significant change in abundance are involved in synaptic vesicle recycling and cytoskeletal integrity. Changes in the abundance of proteins related to RNA splicing, proteostasis, redox homeostasis, mitochondrial function, and energy metabolism were also detected. In addition, the levels of GNAO1 (guanine nucleotide-binding protein G αo subunit), an important modulator of neuronal transmembrane signaling, were significantly increased in the insoluble protein fraction of torpid bats; this may be due to GNAO1 palmitoylation making it insoluble. Our data provide molecular evidence for the maintenance of neuronal activities in torpid bats and suggest that a reversible palmitoylation of the G protein plays a role in the regulation of neuronal activities during bat hibernation. Copyright © 2017 Elsevier B.V. All rights reserved.

When genome-based approach meets the ‘old but good’: revealing genes involved in the antibacterial activity of Pseudomonas sp. P482 against soft rot pathogens.

Directory of Open Access Journals (Sweden)

Dorota Magdalena Krzyżanowska

2016-05-01

Full Text Available Dickeya solani and Pectobacterium carotovorum subsp. brasili¬ense are recently established species of bacterial plant pathogens causing black leg and soft rot of many vegetables and ornamental plants. Pseudomonas sp. strain P482 inhibits the growth of these pathogens, a desired trait considering the limited measures to combat these diseases. In this study, we determined the genetic background of the antibacterial activity of P482, and established the phylogenetic position of this strain.Pseudomonas sp. P482 was classified as Pseudomonas donghuensis. Genome mining revealed that the P482 genome does not contain genes determining the synthesis of known antimicrobials. However, the ClusterFinder algorithm, designed to detect atypical or novel classes of secondary metabolite gene clusters, predicted 18 such clusters in the genome. Screening of a Tn5 mutant library yielded an antimicrobial negative transposon mutant. The transposon insertion was located in a gene encoding an HpcH/HpaI aldolase/citrate lyase family protein. This gene is located in a hypothetical cluster predicted by the ClusterFinder, together with the downstream homologues of four nfs genes, that confer production of a nonfluorescent siderophore by P. donghuensis HYST. Site-directed inactivation of the HpcH/HpaI aldolase gene, the adjacent short chain dehydrogenase gene, as well as a homologue of an essential nfs cluster gene, all abolished the antimicrobial activity of the P482, suggesting their involvement in a common biosynthesis pathway. However, none of the mutants showed a decreased siderophore yield, neither was the antimicrobial activity of the wild type P482 compromised by high iron bioavailability.A genomic region comprising the nfs cluster and three upstream genes is involved in the antibacterial activity of P. donghuensis P482 against D. solani and P. carotovorum subsp. brasiliense. The genes studied are unique to the two known P. donghuensis strains. This study

Substrate channel in nitrogenase revealed by a molecular dynamics approach.

Science.gov (United States)

Smith, Dayle; Danyal, Karamatullah; Raugei, Simone; Seefeldt, Lance C

2014-04-15

Mo-dependent nitrogenase catalyzes the biological reduction of N2 to two NH3 molecules at FeMo-cofactor buried deep inside the MoFe protein. Access of substrates, such as N2, to the active site is likely restricted by the surrounding protein, requiring substrate channels that lead from the surface to the active site. Earlier studies on crystallographic structures of the MoFe protein have suggested three putative substrate channels. Here, we have utilized submicrosecond atomistic molecular dynamics simulations to allow the nitrogenase MoFe protein to explore its conformational space in an aqueous solution at physiological ionic strength, revealing a putative substrate channel. The viability of this observed channel was tested by examining the free energy of passage of N2 from the surface through the channel to FeMo-cofactor, resulting in the discovery of a very low energy barrier. These studies point to a viable substrate channel in nitrogenase that appears during thermal motions of the protein in an aqueous environment and that approaches a face of FeMo-cofactor earlier implicated in substrate binding.

Deep sequencing of subseafloor eukaryotic rRNA reveals active Fungi across marine subsurface provinces.

Directory of Open Access Journals (Sweden)

William Orsi

Full Text Available The deep marine subsurface is a vast habitat for microbial life where cells may live on geologic timescales. Because DNA in sediments may be preserved on long timescales, ribosomal RNA (rRNA is suggested to be a proxy for the active fraction of a microbial community in the subsurface. During an investigation of eukaryotic 18S rRNA by amplicon pyrosequencing, unique profiles of Fungi were found across a range of marine subsurface provinces including ridge flanks, continental margins, and abyssal plains. Subseafloor fungal populations exhibit statistically significant correlations with total organic carbon (TOC, nitrate, sulfide, and dissolved inorganic carbon (DIC. These correlations are supported by terminal restriction length polymorphism (TRFLP analyses of fungal rRNA. Geochemical correlations with fungal pyrosequencing and TRFLP data from this geographically broad sample set suggests environmental selection of active Fungi in the marine subsurface. Within the same dataset, ancient rRNA signatures were recovered from plants and diatoms in marine sediments ranging from 0.03 to 2.7 million years old, suggesting that rRNA from some eukaryotic taxa may be much more stable than previously considered in the marine subsurface.

Coseismic landslides reveal near-surface rock strength in a high-relief tectonically active setting

Science.gov (United States)

Gallen, Sean F.; Clark, Marin K.; Godt, Jonathan W.

2014-01-01

We present quantitative estimates of near-surface rock strength relevant to landscape evolution and landslide hazard assessment for 15 geologic map units of the Longmen Shan, China. Strength estimates are derived from a novel method that inverts earthquake peak ground acceleration models and coseismic landslide inventories to obtain material proper- ties and landslide thickness. Aggregate rock strength is determined by prescribing a friction angle of 30° and solving for effective cohesion. Effective cohesion ranges are from 70 kPa to 107 kPa for 15 geologic map units, and are approximately an order of magnitude less than typical laboratory measurements, probably because laboratory tests on hand-sized specimens do not incorporate the effects of heterogeneity and fracturing that likely control near-surface strength at the hillslope scale. We find that strength among the geologic map units studied varies by less than a factor of two. However, increased weakening of units with proximity to the range front, where precipitation and active fault density are the greatest, suggests that cli- matic and tectonic factors overwhelm lithologic differences in rock strength in this high-relief tectonically active setting.

Activation of the jasmonic acid pathway by depletion of the hydroperoxide lyase OsHPL3 reveals crosstalk between the HPL and AOS branches of the oxylipin pathway in rice.

Directory of Open Access Journals (Sweden)

Xiaoqiang Liu

Full Text Available The allene oxide synthase (AOS and hydroperoxide lyase (HPL branches of the oxylipin pathway, which underlie the production of jasmonates and aldehydes, respectively, function in plant responses to a range of stresses. Regulatory crosstalk has been proposed to exist between these two signaling branches; however, there is no direct evidence of this. Here, we identified and characterized a jasmonic acid (JA overproduction mutant, cea62, by screening a rice T-DNA insertion mutant library for lineages that constitutively express the AOS gene. Map-based cloning was used to identify the underlying gene as hydroperoxide lyase OsHPL3. HPL3 expression and the enzyme activity of its product, (E-2-hexenal, were depleted in the cea62 mutant, which resulted in the dramatic overproduction of JA, the activation of JA signaling, and the emergence of the lesion mimic phenotype. A time-course analysis of lesion formation and of the induction of defense responsive genes in the cea62 mutant revealed that the activation of JA biosynthesis and signaling in cea62 was regulated in a developmental manner, as was OsHPL3 activity in the wild-type plant. Microarray analysis showed that the JA-governed defense response was greatly activated in cea62 and this plant exhibited enhanced resistance to the T1 strain of the bacterial blight pathogen Xanthomonasoryzaepvoryzae (Xoo. The wounding response was attenuated in cea62 plants during the early stages of development, but partially recovered when JA levels were elevated during the later stages. In contrast, the wounding response was not altered during the different developmental stages of wild-type plants. These findings suggest that these two branches of the oxylipin pathway exhibit crosstalk with regards to biosynthesis and signaling and cooperate with each other to function in diverse stress responses.

Metagenomics of the Svalbard reindeer rumen microbiome reveals abundance of polysaccharide utilization loci.

Directory of Open Access Journals (Sweden)

Phillip B Pope

Full Text Available Lignocellulosic biomass remains a largely untapped source of renewable energy predominantly due to its recalcitrance and an incomplete understanding of how this is overcome in nature. We present here a compositional and comparative analysis of metagenomic data pertaining to a natural biomass-converting ecosystem adapted to austere arctic nutritional conditions, namely the rumen microbiome of Svalbard reindeer (Rangifer tarandus platyrhynchus. Community analysis showed that deeply-branched cellulolytic lineages affiliated to the Bacteroidetes and Firmicutes are dominant, whilst sequence binning methods facilitated the assemblage of metagenomic sequence for a dominant and novel Bacteroidales clade (SRM-1. Analysis of unassembled metagenomic sequence as well as metabolic reconstruction of SRM-1 revealed the presence of multiple polysaccharide utilization loci-like systems (PULs as well as members of more than 20 glycoside hydrolase and other carbohydrate-active enzyme families targeting various polysaccharides including cellulose, xylan and pectin. Functional screening of cloned metagenome fragments revealed high cellulolytic activity and an abundance of PULs that are rich in endoglucanases (GH5 but devoid of other common enzymes thought to be involved in cellulose degradation. Combining these results with known and partly re-evaluated metagenomic data strongly indicates that much like the human distal gut, the digestive system of herbivores harbours high numbers of deeply branched and as-yet uncultured members of the Bacteroidetes that depend on PUL-like systems for plant biomass degradation.

preliminary phytochemical screening and antimicrobial activity

African Journals Online (AJOL)

DR. AMINU

1Department of Pre-ND and General Studies, School of Technology, Kano State Polytechnic, ... revealed the presence of flavonoids, saponins, tannins, steroids alkaloids and terpenoids. ... phytochemical and antimicrobial activity of extract.

Sensitivity of human auditory cortex to rapid frequency modulation revealed by multivariate representational similarity analysis.

Science.gov (United States)

Joanisse, Marc F; DeSouza, Diedre D

2014-01-01

Functional Magnetic Resonance Imaging (fMRI) was used to investigate the extent, magnitude, and pattern of brain activity in response to rapid frequency-modulated sounds. We examined this by manipulating the direction (rise vs. fall) and the rate (fast vs. slow) of the apparent pitch of iterated rippled noise (IRN) bursts. Acoustic parameters were selected to capture features used in phoneme contrasts, however the stimuli themselves were not perceived as speech per se. Participants were scanned as they passively listened to sounds in an event-related paradigm. Univariate analyses revealed a greater level and extent of activation in bilateral auditory cortex in response to frequency-modulated sweeps compared to steady-state sounds. This effect was stronger in the left hemisphere. However, no regions showed selectivity for either rate or direction of frequency modulation. In contrast, multivoxel pattern analysis (MVPA) revealed feature-specific encoding for direction of modulation in auditory cortex bilaterally. Moreover, this effect was strongest when analyses were restricted to anatomical regions lying outside Heschl's gyrus. We found no support for feature-specific encoding of frequency modulation rate. Differential findings of modulation rate and direction of modulation are discussed with respect to their relevance to phonetic discrimination.

High-frequency microrheology reveals cytoskeleton dynamics in living cells

Science.gov (United States)

Rigato, Annafrancesca; Miyagi, Atsushi; Scheuring, Simon; Rico, Felix

2017-08-01

Living cells are viscoelastic materials, dominated by an elastic response on timescales longer than a millisecond. On shorter timescales, the dynamics of individual cytoskeleton filaments are expected to emerge, but active microrheology measurements on cells accessing this regime are scarce. Here, we develop high-frequency microrheology experiments to probe the viscoelastic response of living cells from 1 Hz to 100 kHz. We report the viscoelasticity of different cell types under cytoskeletal drug treatments. On previously inaccessible short timescales, cells exhibit rich viscoelastic responses that depend on the state of the cytoskeleton. Benign and malignant cancer cells revealed remarkably different scaling laws at high frequencies, providing a unique mechanical fingerprint. Microrheology over a wide dynamic range--up to the frequency characterizing the molecular components--provides a mechanistic understanding of cell mechanics.

Meta-analysis reveals an association between signal transducer and activator of transcription-4 polymorphism and hepatocellular carcinoma risk.

Science.gov (United States)

Zhang, Li; Xu, Kuihua; Liu, Chuanmiao; Chen, Jiasheng

2017-03-01

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related mortality worldwide. Signal transducer and activator of transcription (STAT) proteins play a multitude of important functions in liver pathophysiology. Recent studies have indicated associations of rs7574865 single nucleotide polymorphism (SNP) in the STAT4 gene with various autoimmune diseases. The association between STAT4 polymorphism and the risk of HCC has been analyzed in several studies, but results remain inconsistent. This study used a meta-analysis approach to comprehensively investigate the correlation between STAT4 polymorphism and HCC risk based on previously published reports. Studies were searched from the databases of PubMed, EMBase, Web of Science, and the Chinese National Knowledge Infrastructure up to 31 December 2015. The meta-analysis was carried out based on the statement of Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Eight published studies, consisting of 7503 HCC patients (cases) and 13 831 individuals without HCC (controls), were included in the present study. Meta-analysis of the included studies revealed that STAT4 rs7574865 polymorphism contributed to the risk of HCC under all four genetic models, consisting of the allelic model (G vs. T: odds ratio [OR], 1.25; 95% confidence interval [CI], 1.19-1.30), the dominant effect model (GG + GT vs. TT: OR, 1.52; 95% CI, 1.26-1.84), the recessive effect model (GG vs. GT + TT: OR, 1.35; 95% CI, 1.21-1.50), and the co-dominant effect model (GG vs.. TT: OR, 1.72; 95% CI, 1.42-2.10) comparisons. No publication bias was indicated from either visualization of the funnel plot or Egger's test. A significantly increased risk of HCC associated with the rs7574865 G was found. The rs7574865 polymorphism might be used as one risk factor for HCC. © 2016 The Japan Society of Hepatology.

Activity-Based Profiling of a Physiologic Aglycone Library Reveals Sugar Acceptor Promiscuity of Family 1 UDP-Glucosyltransferases from Grape1[W

Science.gov (United States)

Bönisch, Friedericke; Frotscher, Johanna; Stanitzek, Sarah; Rühl, Ernst; Wüst, Matthias; Bitz, Oliver; Schwab, Wilfried

2014-01-01

Monoterpenols serve various biological functions and accumulate in grape (Vitis vinifera), where a major fraction occurs as nonvolatile glycosides. We have screened the grape genome for sequences with similarity to terpene URIDINE DIPHOSPHATE GLYCOSYLTRANSFERASES (UGTs) from Arabidopsis (Arabidopsis thaliana). A ripening-related expression pattern was shown for three candidates by spatial and temporal expression analyses in five grape cultivars. Transcript accumulation correlated with the production of monoterpenyl β-d-glucosides in grape exocarp during ripening and was low in vegetative tissue. Targeted functional screening of the recombinant UGTs for their biological substrates was performed by activity-based metabolite profiling (ABMP) employing a physiologic library of aglycones built from glycosides isolated from grape. This approach led to the identification of two UDP-glucose:monoterpenol β-d-glucosyltransferases. Whereas VvGT14a glucosylated geraniol, R,S-citronellol, and nerol with similar efficiency, the three allelic forms VvGT15a, VvGT15b, and VvGT15c preferred geraniol over nerol. Kinetic resolution of R,S-citronellol and R,S-linalool was shown for VvGT15a and VvGT14a, respectively. ABMP revealed geraniol as the major biological substrate but also disclosed that these UGTs may add to the production of further glycoconjugates in planta. ABMP of aglycone libraries provides a versatile tool to uncover novel biologically relevant substrates of small-molecule glycosyltransferases that often show broad sugar acceptor promiscuity. PMID:25073706

Mechanism of the Dual Activities of Human CYP17A1 and Binding to Anti-Prostate Cancer Drug Abiraterone Revealed by a Novel V366M Mutation Causing 17,20 Lyase Deficiency

Directory of Open Access Journals (Sweden)

Mónica Fernández-Cancio

2018-04-01

Full Text Available The CYP17A1 gene regulates sex steroid biosynthesis in humans through 17α-hydroxylase/17,20 lyase activities and is a target of anti-prostate cancer drug abiraterone. In a 46, XY patient with female external genitalia, together with a loss of function mutation S441P, we identified a novel missense mutation V366M at the catalytic center of CYP17A1 which preferentially impaired 17,20 lyase activity. Kinetic experiments with bacterially expressed proteins revealed that V366M mutant enzyme can bind and metabolize pregnenolone to 17OH-pregnenolone, but 17OH-pregnenolone binding and conversion to dehydroepiandrosterone (DHEA was impaired, explaining the patient’s steroid profile. Abiraterone could not bind and inhibit the 17α-hydroxylase activity of the CYP17A1-V366M mutant. Molecular dynamics (MD simulations showed that V366M creates a “one-way valve” and suggests a mechanism for dual activities of human CYP17A1 where, after the conversion of pregnenolone to 17OH-pregnenolone, the product exits the active site and re-enters for conversion to dehydroepiandrosterone. The V366M mutant also explained the effectiveness of the anti-prostate cancer drug abiraterone as a potent inhibitor of CYP17A1 by binding tightly at the active site in the WT enzyme. The V366M is the first human mutation to be described at the active site of CYP17A1 that causes isolated 17,20 lyase deficiency. Knowledge about the specificity of CYP17A1 activities is of importance for the development of treatments for polycystic ovary syndrome and inhibitors for prostate cancer therapy.

Revealing the functional neuroanatomy of intrinsic alertness using fMRI: methodological peculiarities.

Science.gov (United States)

Clemens, Benjamin; Zvyagintsev, Mikhail; Sack, Alexander T; Sack, Alexander; Heinecke, Armin; Willmes, Klaus; Sturm, Walter

2011-01-01

Clinical observations and neuroimaging data revealed a right-hemisphere fronto-parietal-thalamic-brainstem network for intrinsic alertness, and additional left fronto-parietal activity during phasic alertness. The primary objective of this fMRI study was to map the functional neuroanatomy of intrinsic alertness as precisely as possible in healthy participants, using a novel assessment paradigm already employed in clinical settings. Both the paradigm and the experimental design were optimized to specifically assess intrinsic alertness, while at the same time controlling for sensory-motor processing. The present results suggest that the processing of intrinsic alertness is accompanied by increased activity within the brainstem, thalamus, anterior cingulate gyrus, right insula, and right parietal cortex. Additionally, we found increased activation in the left hemisphere around the middle frontal gyrus (BA 9), the insula, the supplementary motor area, and the cerebellum. Our results further suggest that rather minute aspects of the experimental design may induce aspects of phasic alertness, which in turn might lead to additional brain activation in left-frontal areas not normally involved in intrinsic alertness. Accordingly, left BA 9 activation may be related to co-activation of the phasic alertness network due to the switch between rest and task conditions functioning as an external warning cue triggering the phasic alertness network. Furthermore, activation of the intrinsic alertness network during fixation blocks due to enhanced expectancy shortly before the switch to the task block might, when subtracted from the task block, lead to diminished activation in the typical right hemisphere intrinsic alertness network. Thus, we cautiously suggest that--as a methodological artifact--left frontal activations might show up due to phasic alertness involvement and intrinsic alertness activations might be weakened due to contrasting with fixation blocks, when assessing the

Live-cell microscopy reveals small molecule inhibitor effects on MAPK pathway dynamics.

Directory of Open Access Journals (Sweden)

Daniel J Anderson

Full Text Available Oncogenic mutations in the mitogen activated protein kinase (MAPK pathway are prevalent in human tumors, making this pathway a target of drug development efforts. Recently, ATP-competitive Raf inhibitors were shown to cause MAPK pathway activation via Raf kinase priming in wild-type BRaf cells and tumors, highlighting the need for a thorough understanding of signaling in the context of small molecule kinase inhibitors. Here, we present critical improvements in cell-line engineering and image analysis coupled with automated image acquisition that allow for the simultaneous identification of cellular localization of multiple MAPK pathway components (KRas, CRaf, Mek1 and Erk2. We use these assays in a systematic study of the effect of small molecule inhibitors across the MAPK cascade either as single agents or in combination. Both Raf inhibitor priming as well as the release from negative feedback induced by Mek and Erk inhibitors cause translocation of CRaf to the plasma membrane via mechanisms that are additive in pathway activation. Analysis of Erk activation and sub-cellular localization upon inhibitor treatments reveals differential inhibition and activation with the Raf inhibitors AZD628 and GDC0879 respectively. Since both single agent and combination studies of Raf and Mek inhibitors are currently in the clinic, our assays provide valuable insight into their effects on MAPK signaling in live cells.

Radio Telescopes Reveal Unseen Galactic Cannibalism

Science.gov (United States)

2008-06-01

Radio-telescope images have revealed previously-unseen galactic cannibalism -- a triggering event that leads to feeding frenzies by gigantic black holes at the cores of galaxies. Astronomers have long suspected that the extra-bright cores of spiral galaxies called Seyfert galaxies are powered by supermassive black holes consuming material. However, they could not see how the material is started on its journey toward the black hole. Optical/Radio Comparison Visible-light (left) and radio (right) image of galaxy pair: Radio image shows gas streaming between galaxies. CREDIT: Kuo et al., NRAO/AUI/NSF Click on image for more graphics. One leading theory said that Seyfert galaxies have been disturbed by close encounters with neighboring galaxies, thus stirring up their gas and bringing more of it within the gravitational reach of the black hole. However, when astronomers looked at Seyferts with visible-light telescopes, only a small fraction showed any evidence of such an encounter. Now, new images of hydrogen gas in Seyferts made using the National Science Foundation's Very Large Array (VLA) radio telescope show the majority of them are, in fact, disturbed by ongoing encounters with neighbor galaxies. "The VLA lifted the veil on what's really happening with these galaxies," said Cheng-Yu Kuo, a graduate student at the University of Virginia. "Looking at the gas in these galaxies clearly showed that they are snacking on their neighbors. This is a dramatic contrast with their appearance in visible starlight," he added. The effect of the galactic encounters is to send gas and dust toward the black hole and produce energy as the material ultimately is consumed. Black holes, concentrations of matter so dense that not even light can escape their gravitational pull, reside at the cores of many galaxies. Depending on how rapidly the black hole is eating, the galaxy can show a wide range of energetic activity. Seyfert galaxies have the mildest version of this activity, while

Altered spontaneous brain activity in patients with acute spinal cord injury revealed by resting-state functional MRI.

Directory of Open Access Journals (Sweden)

Ling Zhu

Full Text Available Previous neuroimaging studies have provided evidence of structural and functional reorganization of brain in patients with chronic spinal cord injury (SCI. However, it remains unknown whether the spontaneous brain activity changes in acute SCI. In this study, we investigated intrinsic brain activity in acute SCI patients using a regional homogeneity (ReHo analysis based on resting-state functional magnetic resonance imaging.A total of 15 patients with acute SCI and 16 healthy controls participated in the study. The ReHo value was used to evaluate spontaneous brain activity, and voxel-wise comparisons of ReHo were performed to identify brain regions with altered spontaneous brain activity between groups. We also assessed the associations between ReHo and the clinical scores in brain regions showing changed spontaneous brain activity.Compared with the controls, the acute SCI patients showed decreased ReHo in the bilateral primary motor cortex/primary somatosensory cortex, bilateral supplementary motor area/dorsal lateral prefrontal cortex, right inferior frontal gyrus, bilateral dorsal anterior cingulate cortex and bilateral caudate; and increased ReHo in bilateral precuneus, the left inferior parietal lobe, the left brainstem/hippocampus, the left cingulate motor area, bilateral insula, bilateral thalamus and bilateral cerebellum. The average ReHo values of the left thalamus and right insula were negatively correlated with the international standards for the neurological classification of spinal cord injury motor scores.Our findings indicate that acute distant neuronal damage has an immediate impact on spontaneous brain activity. In acute SCI patients, the ReHo was prominently altered in brain regions involved in motor execution and cognitive control, default mode network, and which are associated with sensorimotor compensatory reorganization. Abnormal ReHo values in the left thalamus and right insula could serve as potential biomarkers for

Parsing Heterogeneous Striatal Activity

Directory of Open Access Journals (Sweden)

Kae Nakamura

2017-05-01

Full Text Available The striatum is an input channel of the basal ganglia and is well known to be involved in reward-based decision making and learning. At the macroscopic level, the striatum has been postulated to contain parallel functional modules, each of which includes neurons that perform similar computations to support selection of appropriate actions for different task contexts. At the single-neuron level, however, recent studies in monkeys and rodents have revealed heterogeneity in neuronal activity even within restricted modules of the striatum. Looking for generality in the complex striatal activity patterns, here we briefly survey several types of striatal activity, focusing on their usefulness for mediating behaviors. In particular, we focus on two types of behavioral tasks: reward-based tasks that use salient sensory cues and manipulate outcomes associated with the cues; and perceptual decision tasks that manipulate the quality of noisy sensory cues and associate all correct decisions with the same outcome. Guided by previous insights on the modular organization and general selection-related functions of the basal ganglia, we relate striatal activity patterns on these tasks to two types of computations: implementation of selection and evaluation. We suggest that a parsing with the selection/evaluation categories encourages a focus on the functional commonalities revealed by studies with different animal models and behavioral tasks, instead of a focus on aspects of striatal activity that may be specific to a particular task setting. We then highlight several questions in the selection-evaluation framework for future explorations.

Monovalent Cation Activation of the Radical SAM Enzyme Pyruvate Formate-Lyase Activating Enzyme.

Science.gov (United States)

Shisler, Krista A; Hutcheson, Rachel U; Horitani, Masaki; Duschene, Kaitlin S; Crain, Adam V; Byer, Amanda S; Shepard, Eric M; Rasmussen, Ashley; Yang, Jian; Broderick, William E; Vey, Jessica L; Drennan, Catherine L; Hoffman, Brian M; Broderick, Joan B

2017-08-30

Pyruvate formate-lyase activating enzyme (PFL-AE) is a radical S-adenosyl-l-methionine (SAM) enzyme that installs a catalytically essential glycyl radical on pyruvate formate-lyase. We show that PFL-AE binds a catalytically essential monovalent cation at its active site, yet another parallel with B 12 enzymes, and we characterize this cation site by a combination of structural, biochemical, and spectroscopic approaches. Refinement of the PFL-AE crystal structure reveals Na + as the most likely ion present in the solved structures, and pulsed electron nuclear double resonance (ENDOR) demonstrates that the same cation site is occupied by 23 Na in the solution state of the as-isolated enzyme. A SAM carboxylate-oxygen is an M + ligand, and EPR and circular dichroism spectroscopies reveal that both the site occupancy and the identity of the cation perturb the electronic properties of the SAM-chelated iron-sulfur cluster. ENDOR studies of the PFL-AE/[ 13 C-methyl]-SAM complex show that the target sulfonium positioning varies with the cation, while the observation of an isotropic hyperfine coupling to the cation by ENDOR measurements establishes its intimate, SAM-mediated interaction with the cluster. This monovalent cation site controls enzyme activity: (i) PFL-AE in the absence of any simple monovalent cations has little-no activity; and (ii) among monocations, going down Group 1 of the periodic table from Li + to Cs + , PFL-AE activity sharply maximizes at K + , with NH 4 + closely matching the efficacy of K + . PFL-AE is thus a type I M + -activated enzyme whose M + controls reactivity by interactions with the cosubstrate, SAM, which is bound to the catalytic iron-sulfur cluster.

REVEAL: Software Documentation and Platform Migration

Science.gov (United States)

Wilson, Michael A.; Veibell, Victoir T.

2011-01-01

The Research Environment for Vehicle Embedded Analysis on Linux (REVEAL) is reconfigurable data acquisition software designed for network-distributed test and measurement applications. In development since 2001, it has been successfully demonstrated in support of a number of actual missions within NASA's Suborbital Science Program. Improvements to software configuration control were needed to properly support both an ongoing transition to operational status and continued evolution of REVEAL capabilities. For this reason the project described in this report targets REVEAL software source documentation and deployment of the software on a small set of hardware platforms different from what is currently used in the baseline system implementation. This presentation specifically describes the actions taken over a ten week period by two undergraduate student interns and serves as an overview of the content of the final report for that internship.

Cognitive Activities and Instrumental Activity of Daily Living in Older Adults with Mild Cognitive Impairment

Directory of Open Access Journals (Sweden)

Takehiko Doi

2013-10-01

Full Text Available Aims: This study aimed to identify differences in the implementation of cognitive activities and instrumental activities of daily living (IADLs between healthy individuals and subjects with mild cognitive impairment (MCI. Methods: The study included 2,498 cognitively healthy subjects (mean age, 71.2 ± 5.1 years and 809 MCI subjects (mean age, 71.8 ± 5.4 years. The subjects were interviewed regarding their participation in cognitive activities and the implementation of IADLs. Results: We found a significant association between participation in any cognitive activities (p Conclusions: Our study revealed that greater participation in cognitive activity was associated with lower odds of MCI. Participation in cognitive activities may reflect differences between healthy and MCI subjects. To clarify the causal relationship between cognitive activities and MCI, further studies are required.

Proteomic analysis reveals a role for Bcl2-associated athanogene 3 and major vault protein in resistance to apoptosis in senescent cells by regulating ERK1/2 activation.

Science.gov (United States)

Pasillas, Martina P; Shields, Sarah; Reilly, Rebecca; Strnadel, Jan; Behl, Christian; Park, Robin; Yates, John R; Klemke, Richard; Gonias, Steven L; Coppinger, Judith A

2015-01-01

Senescence is a prominent solid tumor response to therapy in which cells avoid apoptosis and instead enter into prolonged cell cycle arrest. We applied a quantitative proteomics screen to identify signals that lead to therapy-induced senescence and discovered that Bcl2-associated athanogene 3 (Bag3) is up-regulated after adriamycin treatment in MCF7 cells. Bag3 is a member of the BAG family of co-chaperones that interacts with Hsp70. Bag3 also regulates major cell-signaling pathways. Mass spectrometry analysis of the Bag3 Complex revealed a novel interaction between Bag3 and Major Vault Protein (MVP). Silencing of Bag3 or MVP shifts the cellular response to adriamycin to favor apoptosis. We demonstrate that Bag3 and MVP contribute to apoptosis resistance in therapy-induced senescence by increasing the level of activation of extracellular signal-regulated kinase1/2 (ERK1/2). Silencing of either Bag3 or MVP decreased ERK1/2 activation and promoted apoptosis in adriamycin-treated cells. An increase in nuclear accumulation of MVP is observed during therapy-induced senescence and the shift in MVP subcellular localization is Bag3-dependent. We propose a model in which Bag3 binds to MVP and facilitates MVP accumulation in the nucleus, which sustains ERK1/2 activation. We confirmed that silencing of Bag3 or MVP shifts the response toward apoptosis and regulates ERK1/2 activation in a panel of diverse breast cancer cell lines. This study highlights Bag3-MVP as an important complex that regulates a potent prosurvival signaling pathway and contributes to chemotherapy resistance in breast cancer. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Factor analysis of regional brain activation in bipolar and healthy individuals reveals a consistent modular structure.

Science.gov (United States)

Fleck, David E; Welge, Jeffrey A; Eliassen, James C; Adler, Caleb M; DelBello, Melissa P; Strakowski, Stephen M

2018-07-01

The neurophysiological substrates of cognition and emotion, as seen with fMRI, are generally explained using modular structures. The present study was designed to probe the modular structure of cognitive-emotional processing in bipolar and healthy individuals using factor analysis and compare the results with current conceptions of the neurophysiology of bipolar disorder. Exploratory factor analysis was used to assess patterns of covariation among brain regions-of-interest activated during the Continuous Performance Task with Emotional and Neutral Distractors in healthy and bipolar individuals without a priori constraints on the number or composition of latent factors. Results indicated a common cognitive-emotional network consisting of prefrontal, medial temporal, limbic, parietal, anterior cingulate and posterior cingulate modules. However, reduced brain activation to emotional stimuli in the frontal, medial temporal and limbic modules was apparent in the bipolar relative to the healthy group, potentially accounting for emotional dysregulation in bipolar disorder. This study is limited by a relatively small sample size recruited at a single site. The results have yet to be validated on a larger independent sample. Although the modular structure of cognitive-emotional processing is similar in bipolar and healthy individuals, activation in response to emotional/neutral cues varies. These findings are not only consistent with recent conceptions of mood regulation in bipolar disorder, but also suggest that regional activation can be considered within tighter modular structures without compromising data interpretation. This demonstration may serve as a template for data reduction in future region-of-interest analyses to increase statistical power. Copyright © 2018 Elsevier B.V. All rights reserved.

Centromeric DNA replication reconstitution reveals DNA loops and ATR checkpoint suppression.

Science.gov (United States)

Aze, Antoine; Sannino, Vincenzo; Soffientini, Paolo; Bachi, Angela; Costanzo, Vincenzo

2016-06-01

Half of the human genome is made up of repetitive DNA. However, mechanisms underlying replication of chromosome regions containing repetitive DNA are poorly understood. We reconstituted replication of defined human chromosome segments using bacterial artificial chromosomes in Xenopus laevis egg extract. Using this approach we characterized the chromatin assembly and replication dynamics of centromeric alpha-satellite DNA. Proteomic analysis of centromeric chromatin revealed replication-dependent enrichment of a network of DNA repair factors including the MSH2-6 complex, which was required for efficient centromeric DNA replication. However, contrary to expectations, the ATR-dependent checkpoint monitoring DNA replication fork arrest could not be activated on highly repetitive DNA due to the inability of the single-stranded DNA binding protein RPA to accumulate on chromatin. Electron microscopy of centromeric DNA and supercoil mapping revealed the presence of topoisomerase I-dependent DNA loops embedded in a protein matrix enriched for SMC2-4 proteins. This arrangement suppressed ATR signalling by preventing RPA hyper-loading, facilitating replication of centromeric DNA. These findings have important implications for our understanding of repetitive DNA metabolism and centromere organization under normal and stressful conditions.

Shared active site architecture between archaeal PolD and multi-subunit RNA polymerases revealed by X-ray crystallography

OpenAIRE

Sauguet , Ludovic; Raia , Pierre; Henneke , Ghislaine; Delarue , Marc

2016-01-01

International audience; Archaeal replicative DNA polymerase D (PolD) constitute an atypical class of DNA polymerases made of a proofreading exonuclease subunit (DP1) and a larger polymerase catalytic subunit (DP2), both with unknown structures. We have determined the crystal structures of Pyrococcus abyssi DP1 and DP2 at 2.5 and 2.2 Å resolution, respectively, revealing a catalytic core strikingly different from all other known DNA polymerases (DNAPs). Rather, the PolD DP2 catalytic core has ...

Near-infrared spectroscopy can reveal increases in brain activity related to animal-assisted therapy

OpenAIRE

Morita, Yuka; Ebara, Fumio; Morita, Yoshimitsu; Horikawa, Etsuo

2017-01-01

[Purpose] Previous studies have indicated that animal-assisted therapy can promote recovery of psychological, social, and physiological function in mental disorders. This study was designed as a pilot evaluation of the use of near-infrared spectroscopy to objectively identify changes in brain activity that could mediate the effect of animal-assisted therapy. [Subjects and Methods] The participants were 20 healthy students (10 males and 10 females; age 19?21 years) of the Faculty of Agricultur...

Mitogenic activation of B cells in vitro: the properties of adherent accessory cells as revealed by partition analysis

Energy Technology Data Exchange (ETDEWEB)

Kettman, J.R.; Soederberg, A.; Lefkovits, I.

1986-08-15

The requirement of B cells activated by mitogen (dextran sulfate plus lipopolysaccharide) for accessory cells was studied by partition analysis. Small numbers of splenic B cells were activated to clonal growth, as determined by visual inspection, and to immunoglobulin (Ig) synthesis, as determined by release of Ig into the culture fluid. By placing irradiated adherent cells in the periphery of the microculture wells and forcing responding cells to different areas of the well (slant experiments), it was observed that no cell contact was necessary for B cell activation, and that promoted contact (Rock and Roll experiments) does not increase the efficiency of activation. Sequential microcultures suggest that only some irradiated adherent cells act as accessory cells, but they can perform this function to more than one B cell. Attempts to perform limiting dilution analysis by varying irradiated adherent cell input showed non-single-hit behavior. When the data were rearranged, taking into account the distribution of irradiated adherent cells, then single-hit behavior with about 1 to 5% of irradiated adherent cells acting as an accessory cells for B cell clonal activation was observed. The evidence suggests that an uncommon irradiated adherent cell releases a soluble factor necessary for B cell activation and/or clonal proliferation.

Tight coupling of astrocyte energy metabolism to synaptic activity revealed by genetically encoded FRET nanosensors in hippocampal tissue.

Science.gov (United States)

Ruminot, Iván; Schmälzle, Jana; Leyton, Belén; Barros, L Felipe; Deitmer, Joachim W

2017-01-01

The potassium ion, K + , a neuronal signal that is released during excitatory synaptic activity, produces acute activation of glucose consumption in cultured astrocytes, a phenomenon mediated by the sodium bicarbonate cotransporter NBCe1 ( SLC4A4). We have explored here the relevance of this mechanism in brain tissue by imaging the effect of neuronal activity on pH, glucose, pyruvate and lactate dynamics in hippocampal astrocytes using BCECF and FRET nanosensors. Electrical stimulation of Schaffer collaterals produced fast activation of glucose consumption in astrocytes with a parallel increase in intracellular pyruvate and biphasic changes in lactate . These responses were blocked by TTX and were absent in tissue slices prepared from NBCe1-KO mice. Direct depolarization of astrocytes with elevated extracellular K + or Ba 2+ mimicked the metabolic effects of electrical stimulation. We conclude that the glycolytic pathway of astrocytes in situ is acutely sensitive to neuronal activity, and that extracellular K + and the NBCe1 cotransporter are involved in metabolic crosstalk between neurons and astrocytes. Glycolytic activation of astrocytes in response to neuronal K + helps to provide an adequate supply of lactate, a metabolite that is released by astrocytes and which acts as neuronal fuel and an intercellular signal.

Mitogenic activation of B cells in vitro: the properties of adherent accessory cells as revealed by partition analysis

International Nuclear Information System (INIS)

Kettman, J.R.; Soederberg, A.; Lefkovits, I.

1986-01-01

The requirement of B cells activated by mitogen (dextran sulfate plus lipopolysaccharide) for accessory cells was studied by partition analysis. Small numbers of splenic B cells were activated to clonal growth, as determined by visual inspection, and to immunoglobulin (Ig) synthesis, as determined by release of Ig into the culture fluid. By placing irradiated adherent cells in the periphery of the microculture wells and forcing responding cells to different areas of the well (slant experiments), it was observed that no cell contact was necessary for B cell activation, and that promoted contact (Rock and Roll experiments) does not increase the efficiency of activation. Sequential microcultures suggest that only some irradiated adherent cells act as accessory cells, but they can perform this function to more than one B cell. Attempts to perform limiting dilution analysis by varying irradiated adherent cell input showed non-single-hit behavior. When the data were rearranged, taking into account the distribution of irradiated adherent cells, then single-hit behavior with about 1 to 5% of irradiated adherent cells acting as an accessory cells for B cell clonal activation was observed. The evidence suggests that an uncommon irradiated adherent cell releases a soluble factor necessary for B cell activation and/or clonal proliferation

Ras activation by SOS: Allosteric regulation by altered fluctuation dynamics

Science.gov (United States)

Iversen, Lars; Tu, Hsiung-Lin; Lin, Wan-Chen; Christensen, Sune M.; Abel, Steven M.; Iwig, Jeff; Wu, Hung-Jen; Gureasko, Jodi; Rhodes, Christopher; Petit, Rebecca S.; Hansen, Scott D.; Thill, Peter; Yu, Cheng-Han; Stamou, Dimitrios; Chakraborty, Arup K.; Kuriyan, John; Groves, Jay T.

2014-01-01

Activation of the small guanosine triphosphatase H-Ras by the exchange factor Son of Sevenless (SOS) is an important hub for signal transduction. Multiple layers of regulation, through protein and membrane interactions, govern activity of SOS. We characterized the specific activity of individual SOS molecules catalyzing nucleotide exchange in H-Ras. Single-molecule kinetic traces revealed that SOS samples a broad distribution of turnover rates through stochastic fluctuations between distinct, long-lived (more than 100 seconds), functional states. The expected allosteric activation of SOS by Ras–guanosine triphosphate (GTP) was conspicuously absent in the mean rate. However, fluctuations into highly active states were modulated by Ras-GTP. This reveals a mechanism in which functional output may be determined by the dynamical spectrum of rates sampled by a small number of enzymes, rather than the ensemble average. PMID:24994643

Transcriptome profiling reveals bisphenol A alternatives activate estrogen receptor alpha in human breast cancer cells

Science.gov (United States)

Plasticizers with estrogenic activity, such as bisphenol A (BPA), have potential adverse health effects in humans. Due to mounting evidence of these health effects, BPA is being phased out and replaced by other bisphenol variants in “BPA-free” products. We have compared estrogeni...

Journey towards active lifestyle and successful ageing among ...

African Journals Online (AJOL)

A research instrument tagged 'Active Lifestyle and Successful Ageing among Pensioners' (ALASAAP) was the main instrument used for the research. Data was analysed using Pearson product correlation moment and multiple regression. The results of the study revealed active lifestyle as a strong positive relationship with ...

Species-related exposure of phase II metabolite gemfibrozil 1-O-β-glucuronide between human and mice: A net induction of mouse P450 activity was revealed.

Science.gov (United States)

Luo, Min; Dai, Manyun; Lin, Hante; Xie, Minzhu; Lin, Jiao; Liu, Aiming; Yang, Julin

2017-12-01

Gemfibrozil is a fibrate drug used widely for dyslipidemia associated with atherosclerosis. Clinically, both gemfibrozil and its phase II metabolite gemfibrozil 1-O-β-glucuronide (gem-glu) are involved in drug-drug interaction (DDI). But the DDI risk caused by gem-glu between human and mice has not been compared. In this study, six volunteers were recruited and took a therapeutic dose of gemfibrozil for 3 days for examination of the gemfibrozil and gem-glu level in human. Male mice were fed a gemfibrozil diet (0.75%) for 7 days, following which a cocktail-based inhibitory DDI experiment was performed. Plasma samples and liver tissues from mice were collected for determination of gemfibrozil, gem-glu concentration and cytochrome p450 enzyme (P450) induction analysis. In human, the molar ratio of gem-glu/gemfibrozil was 15% and 10% at the trough concentration and the concentration at 1.5 h after the 6th dose. In contrast, this molar ratio at steady state in mice was 91%, demonstrating a 6- to 9-fold difference compared with that in human. Interestingly, a net induction of P450 activity and in vivo inductive DDI potential in mice was revealed. The P450 activity was not inhibited although the gem-glu concentration was high. These data suggested species difference of relative gem-glu exposure between human and mice, as well as a net inductive DDI potential of gemfibrozil in mouse model. Copyright © 2017 John Wiley & Sons, Ltd.

Large-Scale Phosphoproteomics Reveals Shp-2 Phosphatase-Dependent Regulators of Pdgf Receptor Signaling

DEFF Research Database (Denmark)

Batth, Tanveer S; Papetti, Moreno; Pfeiffer, Anamarija

2018-01-01

Despite its low cellular abundance, phosphotyrosine (pTyr) regulates numerous cell signaling pathways in health and disease. We applied comprehensive phosphoproteomics to unravel differential regulators of receptor tyrosine kinase (RTK)-initiated signaling networks upon activation by Pdgf-ββ, Fgf-2...... of Pdgfr pTyr signaling. Application of a recently introduced allosteric Shp-2 inhibitor revealed global regulation of the Pdgf-dependent tyrosine phosphoproteome, which significantly impaired cell migration. In addition, we present a list of hundreds of Shp-2-dependent targets and putative substrates...

Simultaneous Activation of Iron- and Thiol-Based Sensor-Regulator Systems by Redox-Active Compounds.

Science.gov (United States)

Lee, Kang-Lok; Yoo, Ji-Sun; Oh, Gyeong-Seok; Singh, Atul K; Roe, Jung-Hye

2017-01-01

Bacteria in natural habitats are exposed to myriad redox-active compounds (RACs), which include producers of reactive oxygen species (ROS) and reactive electrophile species (RES) that alkylate or oxidize thiols. RACs can induce oxidative stress in cells and activate response pathways by modulating the activity of sensitive regulators. However, the effect of a certain compound on the cell has been investigated primarily with respect to a specific regulatory pathway. Since a single compound can exert multiple chemical effects in the cell, its effect can be better understood by time-course monitoring of multiple sensitive regulatory pathways that the compound induces. We investigated the effect of representative RACs by monitoring the activity of three sensor-regulators in the model actinobacterium Streptomyces coelicolor ; SoxR that senses reactive compounds directly through oxidation of its [2Fe-2S] cluster, CatR/PerR that senses peroxides through bound iron, and an anti-sigma factor RsrA that senses RES via disulfide formation. The time course and magnitude of induction of their target transcripts were monitored to predict the chemical activities of each compound in S. coelicolor . Phenazine methosulfate (PMS) was found to be an effective RAC that directly activated SoxR and an effective ROS-producer that induced CatR/PerR with little thiol-perturbing activity. p -Benzoquinone was an effective RAC that directly activated SoxR, with slower ROS-producing activity, and an effective RES that induced the RsrA-SigR system. Plumbagin was an effective RAC that activated SoxR, an effective ROS-producer, and a less agile but effective RES. Diamide was an RES that effectively formed disulfides and a weak RAC that activated SoxR. Monobromobimane was a moderately effective RES and a slow producer of ROS. Interestingly, benzoquinone induced the SigR system by forming adducts on cysteine thiols in RsrA, revealing a new pathway to modulate RsrA activity. Overall, this study showed

DNA repair enzyme APE1 from evolutionarily ancient Hydra reveals redox activity exclusively found in mammalian APE1.

Science.gov (United States)

Pekhale, Komal; Haval, Gauri; Perween, Nusrat; Antoniali, Giulia; Tell, Gianluca; Ghaskadbi, Surendra; Ghaskadbi, Saroj

2017-11-01

Only mammalian apurinic/apyrimidinic endonuclease1 (APE1) has been reported to possess both DNA repair and redox activities. C terminal of the protein is required for base excision repair, while the redox activity resides in the N terminal due to cysteine residues at specific positions. APE1s from other organisms studied so far lack the redox activity in spite of having the N terminal domain. We find that APE1 from the Cnidarian Hydra exhibits both endonuclease and redox activities similar to mammalian APE1. We further show the presence of the three indispensable cysteines in Hydra APE1 for redox activity by site directed mutagenesis. Importance of redox domain but not the repair domain of APE1 in regeneration has been demonstrated by using domain-specific inhibitors. Our findings clearly demonstrate that the redox function of APE1 evolved very early in metazoan evolution and is not a recent acquisition in mammalian APE1 as believed so far. Copyright © 2017 Elsevier B.V. All rights reserved.

Regional passive seismic monitoring reveals dynamic glacier activity on Spitsbergen, Svalbard

Directory of Open Access Journals (Sweden)

Andreas Köhler

2015-12-01

Full Text Available Dynamic glacier activity is increasingly observed through passive seismic monitoring. We analysed near-regional-scale seismicity on the Arctic archipelago of Svalbard to identify seismic icequake signals and to study their spatial–temporal distribution within the 14-year period from 2000 until 2013. This is the first study that uses seismic data recorded on permanent broadband stations to detect and locate icequakes in different regions of Spitsbergen, the main island of the archipelago. A temporary local seismic network and direct observations of glacier calving and surging were used to identify icequake sources. We observed a high number of icequakes with clear spectral peaks between 1 and 8 Hz in different parts of Spitsbergen. Spatial clusters of icequakes could be associated with individual grounded tidewater glaciers and exhibited clear seasonal variability each year with more signals observed during the melt season. Locations at the termini of glaciers, and correlation with visual calving observations in situ at Kronebreen, a glacier in the Kongsfjorden region, show that these icequakes were caused dominantly by calving. Indirect evidence for glacier surging through increased calving seismicity was found in 2003 at Tunabreen, a glacier in central Spitsbergen. Another type of icequake was observed in the area of the Nathorstbreen glacier system. Seismic events occurred upstream of the glacier within a short time period between January and May 2009 during the initial phase of a major glacier surge. This study is the first step towards the generation and implementation of an operational seismic monitoring strategy for glacier dynamics in Svalbard.

Transcriptional activity of Pax3 is co-activated by TAZ

International Nuclear Information System (INIS)

Murakami, Masao; Tominaga, Junji; Makita, Ryosuke; Uchijima, Yasunobu; Kurihara, Yukiko; Nakagawa, Osamu; Asano, Tomoichiro; Kurihara, Hiroki

2006-01-01

Pax3 is a transcription factor which functions in embryonic development and human diseases. In a yeast two-hybrid screen with full-length Pax3 as bait, we isolated a clone encoding transcriptional co-activator with PDZ-binding motif (TAZ) from an E10.5 mouse embryo cDNA library. Co-immunoprecipitation and nuclear co-localization of TAZ with Pax3 suggest that their association is functionally relevant. In situ hybridization revealed TAZ and Pax3 expression to partially overlap in the paraxial mesoderm, limb buds, and the neural tube. In C2C12 myoblast cells and NIH3T3 cells, TAZ enhanced the transcriptional activity of Pax3 on artificial and microphthalmia-associated transcription factor promoter-luciferase constructs, suggesting that TAZ can function as a co-activator of Pax3. Functional interaction between Pax3 and TAZ may provide a clue to clarifying the mechanism by which Pax3 serves as a transcriptional activator during embryogenesis

Revealing the Origin of Activity in Nitrogen-Doped Nanocarbons towards Electrocatalytic Reduction of Carbon Dioxide.

Science.gov (United States)

Xu, Junyuan; Kan, Yuhe; Huang, Rui; Zhang, Bingsen; Wang, Bolun; Wu, Kuang-Hsu; Lin, Yangming; Sun, Xiaoyan; Li, Qingfeng; Centi, Gabriele; Su, Dangsheng

2016-05-23

Carbon nanotubes (CNTs) are functionalized with nitrogen atoms for reduction of carbon dioxide (CO2 ). The investigation explores the origin of the catalyst's activity and the role of nitrogen chemical states therein. The catalysts show excellent performances, with about 90 % current efficiency for CO formation and stability over 60 hours. The Tafel analyses and density functional theory calculations suggest that the reduction of CO2 proceeds through an initial rate-determining transfer of one electron to CO2 , which leads to the formation of carbon dioxide radical anion (CO2 (.-) ). The initial reduction barrier is too high on pristine CNTs, resulting in a very high overpotentials at which the hydrogen evolution reaction dominates over CO2 reduction. The doped nitrogen atoms stabilize the radical anion, thereby lowering the initial reduction barrier and improving the intrinsic activity. The most efficient nitrogen chemical state for this reaction is quaternary nitrogen, followed by pyridinic and pyrrolic nitrogen. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nutrient Intake, Physical Activity and Nutritional Status ... - Tamale

African Journals Online (AJOL)

It brings to light the higher prevalence of overweight and obesity among female adolescents as a consequence of reduced physical activity. The study also reveals the nutritional deficiencies coupled with reduced physical activity in boarding school students as well as the unhealthy eating habits of day school students.

Controlled formation of iron carbides and their performance in Fischer-Tropsch synthesis

KAUST Repository

Wezendonk, Tim A.

2018-04-19

Iron carbides are unmistakably associated with the active phase for Fischer-Tropsch synthesis (FTS). The formation of these carbides is highly dependent on the catalyst formulation, the activation method and the operational conditions. Because of this highly dynamic behavior, studies on active phase performance often lack the direct correlation between catalyst performance and iron carbide phase. For the above reasons, an extensive in situ Mössbauer spectroscopy study on highly dispersed Fe on carbon catalysts (Fe@C) produced through pyrolysis of a Metal Organic Framework was coupled to their FTS performance testing. The preparation of Fe@C catalysts via this MOF mediated synthesis allows control over the active phase formation and therefore provides an ideal model system to study the performance of different iron carbides. Reduction of fresh Fe@C followed by low-temperature Fischer-Tropsch (LTFT) conditions resulted in the formation of the ε′-Fe2.2C, whereas carburization of the fresh catalysts under high-temperature Fischer-Tropsch (HTFT) resulted in the formation of χ-Fe5C2. Furthermore, the different activation methods did not alter other important catalyst properties, as pre- and post-reaction transmission electron microscopy (TEM) characterization confirmed that the iron nanoparticle dispersion was preserved. The weight normalized activities (FTY) of χ-Fe5C2 and ε′-Fe2.2C are virtually identical, whilst it is found that ε′-Fe2.2C is a better hydrogenation catalyst than χ-Fe5C2. The absence of differences under subsequent HTFT experiments, where χ-Fe5C2 is the dominating phase, is a strong indication that the iron carbide phase is responsible for the differences in selectivity.

Analysis of clock-regulated genes in Neurospora reveals widespread posttranscriptional control of metabolic potential

Science.gov (United States)

Hurley, Jennifer M.; Dasgupta, Arko; Emerson, Jillian M.; Zhou, Xiaoying; Ringelberg, Carol S.; Knabe, Nicole; Lipzen, Anna M.; Lindquist, Erika A.; Daum, Christopher G.; Barry, Kerrie W.; Grigoriev, Igor V.; Smith, Kristina M.; Galagan, James E.; Bell-Pedersen, Deborah; Freitag, Michael; Cheng, Chao; Loros, Jennifer J.; Dunlap, Jay C.

2014-01-01

Neurospora crassa has been for decades a principal model for filamentous fungal genetics and physiology as well as for understanding the mechanism of circadian clocks. Eukaryotic fungal and animal clocks comprise transcription-translation–based feedback loops that control rhythmic transcription of a substantial fraction of these transcriptomes, yielding the changes in protein abundance that mediate circadian regulation of physiology and metabolism: Understanding circadian control of gene expression is key to understanding eukaryotic, including fungal, physiology. Indeed, the isolation of clock-controlled genes (ccgs) was pioneered in Neurospora where circadian output begins with binding of the core circadian transcription factor WCC to a subset of ccg promoters, including those of many transcription factors. High temporal resolution (2-h) sampling over 48 h using RNA sequencing (RNA-Seq) identified circadianly expressed genes in Neurospora, revealing that from ∼10% to as much 40% of the transcriptome can be expressed under circadian control. Functional classifications of these genes revealed strong enrichment in pathways involving metabolism, protein synthesis, and stress responses; in broad terms, daytime metabolic potential favors catabolism, energy production, and precursor assembly, whereas night activities favor biosynthesis of cellular components and growth. Discriminative regular expression motif elicitation (DREME) identified key promoter motifs highly correlated with the temporal regulation of ccgs. Correlations between ccg abundance from RNA-Seq, the degree of ccg-promoter activation as reported by ccg-promoter–luciferase fusions, and binding of WCC as measured by ChIP-Seq, are not strong. Therefore, although circadian activation is critical to ccg rhythmicity, posttranscriptional regulation plays a major role in determining rhythmicity at the mRNA level. PMID:25362047

Phylogenetic investigation of a statewide HIV-1 epidemic reveals ongoing and active transmission networks among men who have sex with men

Science.gov (United States)

Chan, Philip A.; Hogan, Joseph W.; Huang, Austin; DeLong, Allison; Salemi, Marco; Mayer, Kenneth H.; Kantor, Rami

2015-01-01

Background Molecular epidemiologic evaluation of HIV-1 transmission networks can elucidate behavioral components of transmission that can be targets for intervention. Methods We combined phylogenetic and statistical approaches using pol sequences from patients diagnosed 2004-2011 at a large HIV center in Rhode Island, following 75% of the state’s HIV population. Phylogenetic trees were constructed using maximum likelihood and putative transmission clusters were evaluated using latent class analyses (LCA) to determine association of cluster size with underlying demographic/behavioral characteristics. A logistic growth model was used to assess intra-cluster dynamics over time and predict “active” clusters that were more likely to harbor undiagnosed infections. Results Of 1,166 HIV-1 subtype B sequences, 31% were distributed among 114 statistically-supported, monophyletic clusters (range: 2-15 sequences/cluster). Sequences from men who have sex with men (MSM) formed 52% of clusters. LCA demonstrated that sequences from recently diagnosed (2008-2011) MSM with primary HIV infection (PHI) and other sexually transmitted infections (STIs) were more likely to form larger clusters (Odds Ratio 1.62-11.25, ppornographic stores. Four large clusters with 38 sequences (100% male, 89% MSM) had a high-probability of harboring undiagnosed infections and included younger MSM with PHI and STIs. Conclusions In this first large-scale molecular epidemiologic investigation of HIV-1 transmission in New England, sexual networks among recently diagnosed MSM with PHI and concomitant STIs contributed to ongoing transmission. Characterization of transmission dynamics revealed actively growing clusters which may be targets for intervention. PMID:26258569

B-Cell-Specific Diversion of Glucose Carbon Utilization Reveals a Unique Vulnerability in B Cell Malignancies.

Science.gov (United States)

Xiao, Gang; Chan, Lai N; Klemm, Lars; Braas, Daniel; Chen, Zhengshan; Geng, Huimin; Zhang, Qiuyi Chen; Aghajanirefah, Ali; Cosgun, Kadriye Nehir; Sadras, Teresa; Lee, Jaewoong; Mirzapoiazova, Tamara; Salgia, Ravi; Ernst, Thomas; Hochhaus, Andreas; Jumaa, Hassan; Jiang, Xiaoyan; Weinstock, David M; Graeber, Thomas G; Müschen, Markus

2018-04-05

B cell activation during normal immune responses and oncogenic transformation impose increased metabolic demands on B cells and their ability to retain redox homeostasis. While the serine/threonine-protein phosphatase 2A (PP2A) was identified as a tumor suppressor in multiple types of cancer, our genetic studies revealed an essential role of PP2A in B cell tumors. Thereby, PP2A redirects glucose carbon utilization from glycolysis to the pentose phosphate pathway (PPP) to salvage oxidative stress. This unique vulnerability reflects constitutively low PPP activity in B cells and transcriptional repression of G6PD and other key PPP enzymes by the B cell transcription factors PAX5 and IKZF1. Reflecting B-cell-specific transcriptional PPP-repression, glucose carbon utilization in B cells is heavily skewed in favor of glycolysis resulting in lack of PPP-dependent antioxidant protection. These findings reveal a gatekeeper function of the PPP in a broad range of B cell malignancies that can be efficiently targeted by small molecule inhibition of PP2A and G6PD. Copyright © 2018 Elsevier Inc. All rights reserved.

Antibacterial activity of some selected plants traditionally used as ...

African Journals Online (AJOL)

SAM

2014-03-26

Mar 26, 2014 ... K. Womens'College, Kongkhampat,Nambol-795134, Manipur, India. 2Department of Life Science and Bioinformatics, Assam University, Silchar, ... antibacterial activity. The study revealed that all extracts show varied degree of antibacterial activity against the tested bacterial pathogens. The antibacterial ...

Optogenetic Inhibition Reveals Distinct Roles for Basolateral Amygdala Activity at Discrete Time Points during Risky Decision Making.

Science.gov (United States)

Orsini, Caitlin A; Hernandez, Caesar M; Singhal, Sarthak; Kelly, Kyle B; Frazier, Charles J; Bizon, Jennifer L; Setlow, Barry

2017-11-29

Decision making is a multifaceted process, consisting of several distinct phases that likely require different cognitive operations. Previous work showed that the basolateral amygdala (BLA) is a critical substrate for decision making involving risk of punishment; however, it is unclear how the BLA is recruited at different stages of the decision process. To this end, the current study used optogenetics to inhibit the BLA during specific task phases in a model of risky decision making (risky decision-making task) in which rats choose between a small, "safe" reward and a large reward accompanied by varying probabilities of footshock punishment. Male Long-Evans rats received intra-BLA microinjections of viral vectors carrying either halorhodopsin (eNpHR3.0-mCherry) or mCherry alone (control) followed by optic fiber implants and were trained in the risky decision-making task. Laser delivery during the task occurred during intertrial interval, deliberation, or reward outcome phases, the latter of which was further divided into the three possible outcomes (small, safe; large, unpunished; large, punished). Inhibition of the BLA selectively during the deliberation phase decreased choice of the large, risky outcome (decreased risky choice). In contrast, BLA inhibition selectively during delivery of the large, punished outcome increased risky choice. Inhibition had no effect during the other phases, nor did laser delivery affect performance in control rats. Collectively, these data indicate that the BLA can either inhibit or promote choice of risky options, depending on the phase of the decision process in which it is active. SIGNIFICANCE STATEMENT To date, most behavioral neuroscience research on neural mechanisms of decision making has used techniques that preclude assessment of distinct phases of the decision process. Here we show that optogenetic inhibition of the BLA has opposite effects on choice behavior in a rat model of risky decision making, depending on the phase

Artificial spatiotemporal touch inputs reveal complementary decoding in neocortical neurons.

Science.gov (United States)

Oddo, Calogero M; Mazzoni, Alberto; Spanne, Anton; Enander, Jonas M D; Mogensen, Hannes; Bengtsson, Fredrik; Camboni, Domenico; Micera, Silvestro; Jörntell, Henrik

2017-04-04

Investigations of the mechanisms of touch perception and decoding has been hampered by difficulties in achieving invariant patterns of skin sensor activation. To obtain reproducible spatiotemporal patterns of activation of sensory afferents, we used an artificial fingertip equipped with an array of neuromorphic sensors. The artificial fingertip was used to transduce real-world haptic stimuli into spatiotemporal patterns of spikes. These spike patterns were delivered to the skin afferents of the second digit of rats via an array of stimulation electrodes. Combined with low-noise intra- and extracellular recordings from neocortical neurons in vivo, this approach provided a previously inaccessible high resolution analysis of the representation of tactile information in the neocortical neuronal circuitry. The results indicate high information content in individual neurons and reveal multiple novel neuronal tactile coding features such as heterogeneous and complementary spatiotemporal input selectivity also between neighboring neurons. Such neuronal heterogeneity and complementariness can potentially support a very high decoding capacity in a limited population of neurons. Our results also indicate a potential neuroprosthetic approach to communicate with the brain at a very high resolution and provide a potential novel solution for evaluating the degree or state of neurological disease in animal models.

Dissection of TALE-dependent gene activation reveals that they induce transcription cooperatively and in both orientations.

Science.gov (United States)

Streubel, Jana; Baum, Heidi; Grau, Jan; Stuttman, Johannes; Boch, Jens

2017-01-01

Plant-pathogenic Xanthomonas bacteria inject transcription activator-like effector proteins (TALEs) into host cells to specifically induce transcription of plant genes and enhance susceptibility. Although the DNA-binding mode is well-understood it is still ambiguous how TALEs initiate transcription and whether additional promoter elements are needed to support this. To systematically dissect prerequisites for transcriptional initiation the activity of one TALE was compared on different synthetic Bs4 promoter fragments. In addition, a large collection of artificial TALEs spanning the OsSWEET14 promoter was compared. We show that the presence of a TALE alone is not sufficient to initiate transcription suggesting the requirement of additional supporting promoter elements. At the OsSWEET14 promoter TALEs can initiate transcription from various positions, in a synergistic manner of multiple TALEs binding in parallel to the promoter, and even by binding in reverse orientation. TALEs are known to shift the transcriptional start site, but our data show that this shift depends on the individual position of a TALE within a promoter context. Our results implicate that TALEs function like classical enhancer-binding proteins and initiate transcription in both orientations which has consequences for in planta target gene prediction and design of artificial activators.

Perceptual incongruence influences bistability and cortical activation.

Directory of Open Access Journals (Sweden)

Gijs Joost Brouwer

Full Text Available We employed a parametric psychophysical design in combination with functional imaging to examine the influence of metric changes in perceptual incongruence on perceptual alternation rates and cortical responses. Subjects viewed a bistable stimulus defined by incongruent depth cues; bistability resulted from incongruence between binocular disparity and monocular perspective cues that specify different slants (slant rivalry. Psychophysical results revealed that perceptual alternation rates were positively correlated with the degree of perceived incongruence. Functional imaging revealed systematic increases in activity that paralleled the psychophysical results within anterior intraparietal sulcus, prior to the onset of perceptual alternations. We suggest that this cortical activity predicts the frequency of subsequent alternations, implying a putative causal role for these areas in initiating bistable perception. In contrast, areas implicated in form and depth processing (LOC and V3A were sensitive to the degree of slant, but failed to show increases in activity when these cues were in conflict.

Marine Peptides and Their Anti-Infective Activities

Directory of Open Access Journals (Sweden)

Hee Kyoung Kang

2015-01-01

Full Text Available Marine bioresources are a valuable source of bioactive compounds with industrial and nutraceutical potential. Numerous clinical trials evaluating novel chemotherapeutic agents derived from marine sources have revealed novel mechanisms of action. Recently, marine-derived bioactive peptides have attracted attention owing to their numerous beneficial effects. Moreover, several studies have reported that marine peptides exhibit various anti-infective activities, such as antimicrobial, antifungal, antimalarial, antiprotozoal, anti-tuberculosis, and antiviral activities. In the last several decades, studies of marine plants, animals, and microbes have revealed tremendous number of structurally diverse and bioactive secondary metabolites. However, the treatments available for many infectious diseases caused by bacteria, fungi, and viruses are limited. Thus, the identification of novel antimicrobial peptides should be continued, and all possible strategies should be explored. In this review, we will present the structures and anti-infective activity of peptides isolated from marine sources (sponges, algae, bacteria, fungi and fish from 2006 to the present.

Repetition-related reductions in neural activity reveal component processes of mental simulation.

Science.gov (United States)

Szpunar, Karl K; St Jacques, Peggy L; Robbins, Clifford A; Wig, Gagan S; Schacter, Daniel L

2014-05-01

In everyday life, people adaptively prepare for the future by simulating dynamic events about impending interactions with people, objects and locations. Previous research has consistently demonstrated that a distributed network of frontal-parietal-temporal brain regions supports this ubiquitous mental activity. Nonetheless, little is known about the manner in which specific regions of this network contribute to component features of future simulation. In two experiments, we used a functional magnetic resonance (fMR)-repetition suppression paradigm to demonstrate that distinct frontal-parietal-temporal regions are sensitive to processing the scenarios or what participants imagined was happening in an event (e.g., medial prefrontal, posterior cingulate, temporal-parietal and middle temporal cortices are sensitive to the scenarios associated with future social events), people (medial prefrontal cortex), objects (inferior frontal and premotor cortices) and locations (posterior cingulate/retrosplenial, parahippocampal and posterior parietal cortices) that typically constitute simulations of personal future events. This pattern of results demonstrates that the neural substrates of these component features of event simulations can be reliably identified in the context of a task that requires participants to simulate complex, everyday future experiences.

Stretch-activated cation channel from larval bullfrog skin

DEFF Research Database (Denmark)

Hillyard, Stanley D; Willumsen, Niels J; Marrero, Mario B

2010-01-01

Cell-attached patches from isolated epithelial cells from larval bullfrog skin revealed a cation channel that was activated by applying suction (-1 kPa to -4.5 kPa) to the pipette. Activation was characterized by an initial large current spike that rapidly attenuated to a stable value and showed ...

The Structure of the MAP2K MEK6 Reveals an Autoinhibitory Dimer

Energy Technology Data Exchange (ETDEWEB)

Min, Xiaoshan; Akella, Radha; He, Haixia; Humphreys, John M.; Tsutakawa, Susan E.; Lee, Seung-Jae; Tainer, John A.; Cobb, Melanie H.; Goldsmith, Elizabeth J.

2009-07-13

MAP2Ks are dual-specificity protein kinases functioning at the center of three-tiered MAP kinase modules. The structure of the kinase domain of the MAP2K MEK6 with phosphorylation site mimetic aspartic acid mutations (MEK6/{Delta}N/DD) has been solved at 2.3 {angstrom} resolution. The structure reveals an autoinhibited elongated ellipsoidal dimer. The enzyme adopts an inactive conformation, based upon structural queues, despite the phosphomimetic mutations. Gel filtration and small-angle X-ray scattering analysis confirm that the crystallographically observed ellipsoidal dimer is a feature of MEK6/{Delta}N/DD and full-length unphosphorylated wild-type MEK6 in solution. The interface includes the phosphate binding ribbon of each subunit, part of the activation loop, and a rare 'arginine stack' between symmetry-related arginine residues in the N-terminal lobe. The autoinhibited structure likely confers specificity on active MAP2Ks. The dimer may also serve the function in unphosphorylated MEK6 of preventing activation loop phosphorylation by inappropriate kinases.

Calcium Imaging Reveals Coordinated Simple Spike Pauses in Populations of Cerebellar Purkinje Cells

Directory of Open Access Journals (Sweden)

Jorge E. Ramirez

2016-12-01

Full Text Available The brain’s control of movement is thought to involve coordinated activity between cerebellar Purkinje cells. The results reported here demonstrate that somatic Ca2+ imaging is a faithful reporter of Na+-dependent “simple spike” pauses and enables us to optically record changes in firing rates in populations of Purkinje cells in brain slices and in vivo. This simultaneous calcium imaging of populations of Purkinje cells reveals a striking spatial organization of pauses in Purkinje cell activity between neighboring cells. The source of this organization is shown to be the presynaptic gamma-Aminobutyric acid producing (GABAergic network, and blocking ionotropic gamma-Aminobutyric acid receptor (GABAARs abolishes the synchrony. These data suggest that presynaptic interneurons synchronize (inactivity between neighboring Purkinje cells, and thereby maximize their effect on downstream targets in the deep cerebellar nuclei.

Chemical proteomics approach reveals the direct targets and the heme-dependent activation mechanism of artemisinin in Plasmodium falciparum using an activity-based artemisinin probe

Directory of Open Access Journals (Sweden)

Jigang Wang

2016-04-01

Full Text Available Artemisinin and its analogues are currently the most effective anti-malarial drugs. The activation of artemisinin requires the cleavage of the endoperoxide bridge in the presence of iron sources. Once activated, artemisinins attack macromolecules through alkylation and propagate a series of damages, leading to parasite death. Even though several parasite proteins have been reported as artemisinin targets, the exact mechanism of action (MOA of artemisinin is still controversial and its high potency and specificity against the malaria parasite could not be fully accounted for. Recently, we have developed an unbiased chemical proteomics approach to directly probe the MOA of artemisinin in P. falciparum. We synthesized an activity-based artemisinin probe with an alkyne tag, which can be coupled with biotin through click chemistry. This enabled selective purification and identification of 124 protein targets of artemisinin. Many of these targets are critical for the parasite survival. In vitro assays confirmed the specific artemisinin binding and inhibition of selected targets. We thus postulated that artemisinin kills the parasite through disrupting its biochemical landscape. In addition, we showed that artemisinin activation requires heme, rather than free ferrous iron, by monitoring the extent of protein binding using a fluorescent dye coupled with the alkyne-tagged artemisinin. The extremely high level of heme released from the hemoglobin digestion by the parasite makes artemisinin exceptionally potent against late-stage parasites (trophozoite and schizont stages compared to parasites at early ring stage, which have low level of heme, possibly derived from endogenous synthesis. Such a unique activation mechanism also confers artemisinin with extremely high specificity against the parasites, while the healthy red blood cells are unaffected. Our results provide a sound explanation of the MOA of artemisinin and its specificity against malaria

Growth hormone receptor-deficient pigs resemble the pathophysiology of human Laron syndrome and reveal altered activation of signaling cascades in the liver.

Science.gov (United States)

Hinrichs, Arne; Kessler, Barbara; Kurome, Mayuko; Blutke, Andreas; Kemter, Elisabeth; Bernau, Maren; Scholz, Armin M; Rathkolb, Birgit; Renner, Simone; Bultmann, Sebastian; Leonhardt, Heinrich; de Angelis, Martin Hrabĕ; Nagashima, Hiroshi; Hoeflich, Andreas; Blum, Werner F; Bidlingmaier, Martin; Wanke, Rüdiger; Dahlhoff, Maik; Wolf, Eckhard

2018-05-01

Laron syndrome (LS) is a rare, autosomal recessive disorder in humans caused by loss-of-function mutations of the growth hormone receptor (GHR) gene. To establish a large animal model for LS, pigs with GHR knockout (KO) mutations were generated and characterized. CRISPR/Cas9 technology was applied to mutate exon 3 of the GHR gene in porcine zygotes. Two heterozygous founder sows with a 1-bp or 7-bp insertion in GHR exon 3 were obtained, and their heterozygous F1 offspring were intercrossed to produce GHR-KO, heterozygous GHR mutant, and wild-type pigs. Since the latter two groups were not significantly different in any parameter investigated, they were pooled as the GHR expressing control group. The characterization program included body and organ growth, body composition, endocrine and clinical-chemical parameters, as well as signaling studies in liver tissue. GHR-KO pigs lacked GHR and had markedly reduced serum insulin-like growth factor 1 (IGF1) levels and reduced IGF-binding protein 3 (IGFBP3) activity but increased IGFBP2 levels. Serum GH concentrations were significantly elevated compared with control pigs. GHR-KO pigs had a normal birth weight. Growth retardation became significant at the age of five weeks. At the age of six months, the body weight of GHR-KO pigs was reduced by 60% compared with controls. Most organ weights of GHR-KO pigs were reduced proportionally to body weight. However, the weights of liver, kidneys, and heart were disproportionately reduced, while the relative brain weight was almost doubled. GHR-KO pigs had a markedly increased percentage of total body fat relative to body weight and displayed transient juvenile hypoglycemia along with decreased serum triglyceride and cholesterol levels. Analysis of insulin receptor related signaling in the liver of adult fasted pigs revealed increased phosphorylation of IRS1 and PI3K. In agreement with the loss of GHR, phosphorylation of STAT5 was significantly reduced. In contrast, phosphorylation

Growth hormone receptor-deficient pigs resemble the pathophysiology of human Laron syndrome and reveal altered activation of signaling cascades in the liver

Directory of Open Access Journals (Sweden)

Arne Hinrichs

2018-05-01

Full Text Available Objective: Laron syndrome (LS is a rare, autosomal recessive disorder in humans caused by loss-of-function mutations of the growth hormone receptor (GHR gene. To establish a large animal model for LS, pigs with GHR knockout (KO mutations were generated and characterized. Methods: CRISPR/Cas9 technology was applied to mutate exon 3 of the GHR gene in porcine zygotes. Two heterozygous founder sows with a 1-bp or 7-bp insertion in GHR exon 3 were obtained, and their heterozygous F1 offspring were intercrossed to produce GHR-KO, heterozygous GHR mutant, and wild-type pigs. Since the latter two groups were not significantly different in any parameter investigated, they were pooled as the GHR expressing control group. The characterization program included body and organ growth, body composition, endocrine and clinical-chemical parameters, as well as signaling studies in liver tissue. Results: GHR-KO pigs lacked GHR and had markedly reduced serum insulin-like growth factor 1 (IGF1 levels and reduced IGF-binding protein 3 (IGFBP3 activity but increased IGFBP2 levels. Serum GH concentrations were significantly elevated compared with control pigs. GHR-KO pigs had a normal birth weight. Growth retardation became significant at the age of five weeks. At the age of six months, the body weight of GHR-KO pigs was reduced by 60% compared with controls. Most organ weights of GHR-KO pigs were reduced proportionally to body weight. However, the weights of liver, kidneys, and heart were disproportionately reduced, while the relative brain weight was almost doubled. GHR-KO pigs had a markedly increased percentage of total body fat relative to body weight and displayed transient juvenile hypoglycemia along with decreased serum triglyceride and cholesterol levels. Analysis of insulin receptor related signaling in the liver of adult fasted pigs revealed increased phosphorylation of IRS1 and PI3K. In agreement with the loss of GHR, phosphorylation of STAT5 was

Maternidad, feminidad, sexualidad. Algunos aspectos de las Primeras jornadas eugénicas españolas (Madrid, 1928-Madrid, 1933

Directory of Open Access Journals (Sweden)

Marie-Aline Barrachina

2004-12-01

Full Text Available This article studies the proceedings of the «Primeras jornadas eugénicas españolas», which took place in the spring of 1933 after an abortive first attempt in 1928. Study of the two volumes of proceedings provides evidence of the ideological and political framework of the medical and juridical debate about sexuality in the 1920s and 1930s. In 1928, the Primo de Rivera dictatorship intervened to prevent the «pornographic indulgence» represented by the series of planned conferences, cutting off at the root social and political debate on an urgent problem in Spanish society: birth control and family planning. The second congress, in the final months of the «bieno reformador» (1931-1933, reveals the abyss that separated even those groups who appeared politically and ideologically closest. Now that sexuality had been removed from the confession booth, the question of the ethical and juridical limits of state intervention could be raised, and there was little hesitation in expressing viewpoints with an unmistakably totalitarian colour, alongside humanist and feminist perspectives, all of them extremely modern. Sexual difference and identity, maternity and sexuality, and female and sexual emancipation, were themes that, by raising the possibility of another sexual order, allowed the participants in the congress to glimpse the contours of a world that was unprecedented and shocking, even for the most progressive.

Experimental single-strain mobilomics reveals events that shape pathogen emergence.

Science.gov (United States)

Schoeniger, Joseph S; Hudson, Corey M; Bent, Zachary W; Sinha, Anupama; Williams, Kelly P

2016-08-19

Virulence genes on mobile DNAs such as genomic islands (GIs) and plasmids promote bacterial pathogen emergence. Excision is an early step in GI mobilization, producing a circular GI and a deletion site in the chromosome; circular forms are also known for some bacterial insertion sequences (ISs). The recombinant sequence at the junctions of such circles and deletions can be detected sensitively in high-throughput sequencing data, using new computational methods that enable empirical discovery of mobile DNAs. For the rich mobilome of a hospital Klebsiella pneumoniae strain, circularization junctions (CJs) were detected for six GIs and seven IS types. Our methods revealed differential biology of multiple mobile DNAs, imprecision of integrases and transposases, and differential activity among identical IS copies for IS26, ISKpn18 and ISKpn21 Using the resistance of circular dsDNA molecules to exonuclease, internally calibrated with the native plasmids, showed that not all molecules bearing GI CJs were circular. Transpositions were also detected, revealing replicon preference (ISKpn18 prefers a conjugative IncA/C2 plasmid), local action (IS26), regional preferences, selection (against capsule synthesis) and IS polarity inversion. Efficient discovery and global characterization of numerous mobile elements per experiment improves accounting for the new gene combinations that arise in emerging pathogens. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Nucleolar Proteome Analysis and Proteasomal Activity Assays Reveal a Link between Nucleolus and 26S Proteasome in A. thaliana

Science.gov (United States)

Montacié, Charlotte; Durut, Nathalie; Opsomer, Alison; Palm, Denise; Comella, Pascale; Picart, Claire; Carpentier, Marie-Christine; Pontvianne, Frederic; Carapito, Christine; Schleiff, Enrico; Sáez-Vásquez, Julio

2017-01-01

In all eukaryotic cells, the nucleolus is functionally and structurally linked to rRNA synthesis and ribosome biogenesis. This compartment contains as well factors involved in other cellular activities, but the functional interconnection between non-ribosomal activities and the nucleolus (structure and function) still remains an open question. Here, we report a novel mass spectrometry analysis of isolated nucleoli from Arabidopsis thaliana plants using the FANoS (Fluorescence Assisted Nucleolus Sorting) strategy. We identified many ribosome biogenesis factors (RBF) and proteins non-related with ribosome biogenesis, in agreement with the recognized multi-functionality of the nucleolus. Interestingly, we found that 26S proteasome subunits localize in the nucleolus and demonstrated that proteasome activity and nucleolus organization are intimately linked to each other. Proteasome subunits form discrete foci in the disorganized nucleolus of nuc1.2 plants. Nuc1.2 protein extracts display reduced proteasome activity in vitro compared to WT protein extracts. Remarkably, proteasome activity in nuc1.2 is similar to proteasome activity in WT plants treated with proteasome inhibitors (MG132 or ALLN). Finally, we show that MG132 treatment induces disruption of nucleolar structures in WT but not in nuc1.2 plants. Altogether, our data suggest a functional interconnection between nucleolus structure and proteasome activity. PMID:29104584

CAFET algorithm reveals Wnt/PCP signature in lung squamous cell carcinoma.

Directory of Open Access Journals (Sweden)

Yue Hu

Full Text Available We analyzed the gene expression patterns of 138 Non-Small Cell Lung Cancer (NSCLC samples and developed a new algorithm called Coverage Analysis with Fisher's Exact Test (CAFET to identify molecular pathways that are differentially activated in squamous cell carcinoma (SCC and adenocarcinoma (AC subtypes. Analysis of the lung cancer samples demonstrated hierarchical clustering according to the histological subtype and revealed a strong enrichment for the Wnt signaling pathway components in the cluster consisting predominantly of SCC samples. The specific gene expression pattern observed correlated with enhanced activation of the Wnt Planar Cell Polarity (PCP pathway and inhibition of the canonical Wnt signaling branch. Further real time RT-PCR follow-up with additional primary tumor samples and lung cancer cell lines confirmed enrichment of Wnt/PCP pathway associated genes in the SCC subtype. Dysregulation of the canonical Wnt pathway, characterized by increased levels of β-catenin and epigenetic silencing of negative regulators, has been reported in adenocarcinoma of the lung. Our results suggest that SCC and AC utilize different branches of the Wnt pathway during oncogenesis.

Signalling pathways involved in adult heart formation revealed by gene expression profiling in Drosophila.

Directory of Open Access Journals (Sweden)

Bruno Zeitouni

2007-10-01

Full Text Available Drosophila provides a powerful system for defining the complex genetic programs that drive organogenesis. Under control of the steroid hormone ecdysone, the adult heart in Drosophila forms during metamorphosis by a remodelling of the larval cardiac organ. Here, we evaluated the extent to which transcriptional signatures revealed by genomic approaches can provide new insights into the molecular pathways that underlie heart organogenesis. Whole-genome expression profiling at eight successive time-points covering adult heart formation revealed a highly dynamic temporal map of gene expression through 13 transcript clusters with distinct expression kinetics. A functional atlas of the transcriptome profile strikingly points to the genomic transcriptional response of the ecdysone cascade, and a sharp regulation of key components belonging to a few evolutionarily conserved signalling pathways. A reverse genetic analysis provided evidence that these specific signalling pathways are involved in discrete steps of adult heart formation. In particular, the Wnt signalling pathway is shown to participate in inflow tract and cardiomyocyte differentiation, while activation of the PDGF-VEGF pathway is required for cardiac valve formation. Thus, a detailed temporal map of gene expression can reveal signalling pathways responsible for specific developmental programs and provides here substantial grasp into heart formation.

Resting-state brain networks revealed by granger causal connectivity in frogs.

Science.gov (United States)

Xue, Fei; Fang, Guangzhan; Yue, Xizi; Zhao, Ermi; Brauth, Steven E; Tang, Yezhong

2016-10-15

Resting-state networks (RSNs) refer to the spontaneous brain activity generated under resting conditions, which maintain the dynamic connectivity of functional brain networks for automatic perception or higher order cognitive functions. Here, Granger causal connectivity analysis (GCCA) was used to explore brain RSNs in the music frog (Babina daunchina) during different behavioral activity phases. The results reveal that a causal network in the frog brain can be identified during the resting state which reflects both brain lateralization and sexual dimorphism. Specifically (1) ascending causal connections from the left mesencephalon to both sides of the telencephalon are significantly higher than those from the right mesencephalon, while the right telencephalon gives rise to the strongest efferent projections among all brain regions; (2) causal connections from the left mesencephalon in females are significantly higher than those in males and (3) these connections are similar during both the high and low behavioral activity phases in this species although almost all electroencephalograph (EEG) spectral bands showed higher power in the high activity phase for all nodes. The functional features of this network match important characteristics of auditory perception in this species. Thus we propose that this causal network maintains auditory perception during the resting state for unexpected auditory inputs as resting-state networks do in other species. These results are also consistent with the idea that females are more sensitive to auditory stimuli than males during the reproductive season. In addition, these results imply that even when not behaviorally active, the frogs remain vigilant for detecting external stimuli. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Feedback Control of Sex Determination by Dosage Compensation Revealed through Caenorhabditis Elegans Sdc-3 Mutations

OpenAIRE

DeLong, L.; Plenefisch, J. D.; Klein, R. D.; Meyer, B. J.

1993-01-01

In Caenorhabditis elegans, sex determination and dosage compensation are coordinately controlled through a group of genes that respond to the primary sex determination signal. Here we describe a new gene, sdc-3, that also controls these processes. In contrast to previously described genes, the sex determination and dosage compensation activities of sdc-3 are separately mutable, indicating that they function independently. Paradoxically, the sdc-3 null phenotype fails to reveal the role of sdc...

Young people's participation in physical activity

DEFF Research Database (Denmark)

Nielsen, Stine Frydendal; Ottesen, Laila; Thing, Lone Friis

regarding physical activity. 469 students participated in the survey. It is carried out through the online program SurveyXact. The data is processed in SPSS, and subsequently discussed. The primary results reveal that spare time jobs have a large impact on young people’s participation in physical activity......; Shame has an immense influence on the girls’ participation in physical activity; The offers regarding physical activity, provided by the school, appeal more to the boys and the students who are already physically active. Consequently, the students express a wish to have more influence on physical...... of young people today. This means that participation in physical activity cannot be discussed independently, but must always be viewed within the context of the lives of young people today....

Evaluation of Anticaries Activity of Selected Mouthwash Marketed in ...

African Journals Online (AJOL)

Anticaries evaluation revealed that 0.047 % thymol in ethanol displayed the highest degree of anticaries activity against all the Streptococcal species tested. Incorporation of preservatives in mouthwashes may adversely affect their anticaries activity as indicated by the fact that the preserved mouthwash exhibited lower ...

Differential patterns of cortical activation as a function of fluid reasoning complexity.

Science.gov (United States)

Perfetti, Bernardo; Saggino, Aristide; Ferretti, Antonio; Caulo, Massimo; Romani, Gian Luca; Onofrj, Marco

2009-02-01

Fluid intelligence (gf) refers to abstract reasoning and problem solving abilities. It is considered a human higher cognitive factor central to general intelligence (g). The regions of the cortex supporting gf have been revealed by recent bioimaging studies and valuable hypothesis on the neural correlates of individual differences have been proposed. However, little is known about the interaction between individual variability in gf and variation in cortical activity following task complexity increase. To further investigate this, two samples of participants (high-IQ, N = 8; low-IQ, N = 10) with significant differences in gf underwent two reasoning (moderate and complex) tasks and a control task adapted from the Raven progressive matrices. Functional magnetic resonance was used and the recorded signal analyzed between and within the groups. The present study revealed two opposite patterns of neural activity variation which were probably a reflection of the overall differences in cognitive resource modulation: when complexity increased, high-IQ subjects showed a signal enhancement in some frontal and parietal regions, whereas low-IQ subjects revealed a decreased activity in the same areas. Moreover, a direct comparison between the groups' activation patterns revealed a greater neural activity in the low-IQ sample when conducting moderate task, with a strong involvement of medial and lateral frontal regions thus suggesting that the recruitment of executive functioning might be different between the groups. This study provides evidence for neural differences in facing reasoning complexity among subjects with different gf level that are mediated by specific patterns of activation of the underlying fronto-parietal network.

Epigenetic Changes during Hepatic Stellate Cell Activation.

Directory of Open Access Journals (Sweden)

Silke Götze

Full Text Available Hepatic stellate cells (HSC, which can participate in liver regeneration and fibrogenesis, have recently been identified as liver-resident mesenchymal stem cells. During their activation HSC adopt a myofibroblast-like phenotype accompanied by profound changes in the gene expression profile. DNA methylation changes at single genes have been reported during HSC activation and may participate in the regulation of this process, but comprehensive DNA methylation analyses are still missing. The aim of the present study was to elucidate the role of DNA methylation during in vitro activation of HSC.The analysis of DNA methylation changes by antibody-based assays revealed a strong decrease in the global DNA methylation level during culture-induced activation of HSC. To identify genes which may be regulated by DNA methylation, we performed a genome-wide Methyl-MiniSeq EpiQuest sequencing comparing quiescent and early culture-activated HSC. Approximately 400 differentially methylated regions with a methylation change of at least 20% were identified, showing either hypo- or hypermethylation during activation. Further analysis of selected genes for DNA methylation and expression were performed revealing a good correlation between DNA methylation changes and gene expression. Furthermore, global DNA demethylation during HSC activation was investigated by 5-bromo-2-deoxyuridine assay and L-mimosine treatment showing that demethylation was independent of DNA synthesis and thereby excluding a passive DNA demethylation mechanism.In summary, in vitro activation of HSC initiated strong DNA methylation changes, which were associated with gene regulation. These results indicate that epigenetic mechanisms are important for the control of early HSC activation. Furthermore, the data show that global DNA demethylation during activation is based on an active DNA demethylation mechanism.

Vocal activities reflect the temporal distribution of bottlenose dolphin social and non-social activity in a zoological park.

Science.gov (United States)

Lima, Alice; Lemasson, Alban; Boye, Martin; Hausberger, Martine

2017-12-01

Under natural conditions bottlenose dolphins (Tursiops truncatus) spend their time mostly feeding and then travelling, socializing, or resting. These activities are not randomly distributed, with feeding being higher in early morning and late afternoon. Social activities and vocal behavior seem to be very important in dolphin daily activity. This study aimed to describe the activity time-budget and its relation to vocal behavior for dolphins in a zoological park. We recorded behaviors and vocalizations of six dolphins over 2 months. All subjects performed more non-agonistic social interactions and play in the morning than in the afternoon. The different categories of vocalizations were distributed non-randomly throughout the day, with more chirps in the afternoon, when the animals were "less social." The most striking result was the strong correlation between activities and the categories of vocalizations produced. The results confirm the association between burst pulses and whistles with social activities, but also reveal that both are also associated with solitary play. More chirps were produced when dolphins were engaged in socio-sexual behaviors, emphasizing the need for further questioning about the function of this vocal category. This study reveals that: (i) in a group kept in zoological management, social activities are mostly present in the morning; and (ii) the acoustic signals produced by dolphins may give a reliable representation of their current activities. While more studies on the context of signal production are needed, our findings provide a useful tool for understanding free ranging dolphin behavior when they are not visible. © 2017 Wiley Periodicals, Inc.

Single-Cell Transcriptomics Reveals a Population of Dormant Neural Stem Cells that Become Activated upon Brain Injury.

Science.gov (United States)

Llorens-Bobadilla, Enric; Zhao, Sheng; Baser, Avni; Saiz-Castro, Gonzalo; Zwadlo, Klara; Martin-Villalba, Ana

2015-09-03

Heterogeneous pools of adult neural stem cells (NSCs) contribute to brain maintenance and regeneration after injury. The balance of NSC activation and quiescence, as well as the induction of lineage-specific transcription factors, may contribute to diversity of neuronal and glial fates. To identify molecular hallmarks governing these characteristics, we performed single-cell sequencing of an unbiased pool of adult subventricular zone NSCs. This analysis identified a discrete, dormant NSC subpopulation that already expresses distinct combinations of lineage-specific transcription factors during homeostasis. Dormant NSCs enter a primed-quiescent state before activation, which is accompanied by downregulation of glycolytic metabolism, Notch, and BMP signaling and a concomitant upregulation of lineage-specific transcription factors and protein synthesis. In response to brain ischemia, interferon gamma signaling induces dormant NSC subpopulations to enter the primed-quiescent state. This study unveils general principles underlying NSC activation and lineage priming and opens potential avenues for regenerative medicine in the brain. Copyright © 2015 Elsevier Inc. All rights reserved.

Linking anti-predator behaviour to prey demography reveals limited risk effects of an actively hunting large carnivore.

Science.gov (United States)

Middleton, Arthur D; Kauffman, Matthew J; McWhirter, Douglas E; Jimenez, Michael D; Cook, Rachel C; Cook, John G; Albeke, Shannon E; Sawyer, Hall; White, P J

2013-08-01

Ecological theory predicts that the diffuse risk cues generated by wide-ranging, active predators should induce prey behavioural responses but not major, population- or community-level consequences. We evaluated the non-consumptive effects (NCEs) of an active predator, the grey wolf (Canis lupus), by simultaneously tracking wolves and the behaviour, body fat, and pregnancy of elk (Cervus elaphus), their primary prey in the Greater Yellowstone Ecosystem. When wolves approached within 1 km, elk increased their rates of movement, displacement and vigilance. Even in high-risk areas, however, these encounters occurred only once every 9 days. Ultimately, despite 20-fold variation in the frequency of encounters between wolves and individual elk, the risk of predation was not associated with elk body fat or pregnancy. Our findings suggest that the ecological consequences of actively hunting large carnivores, such as the wolf, are more likely transmitted by consumptive effects on prey survival than NCEs on prey behaviour. © 2013 John Wiley & Sons Ltd/CNRS.

ASSESSMENT OF HUMAN RESOURCES FOR REGIONAL INNOVATION ACTIVITY

Directory of Open Access Journals (Sweden)

R. R. Lukyanova

2010-03-01

Full Text Available The paper deals with the issues of human resource development regarding an innovation activity. Concepts of labor and human resources have been surveyed. An integral index for assessment of human resources for regional innovation activity has been developed and assessment of the Russian regions has been made on the basis of it. Development tendencies of modern human resources for innovation activity in Russia have been revealed.

Structural variation of the oceanic Moho in the Pacific plate revealed by active-source seismic data

Science.gov (United States)

Ohira, Akane; Kodaira, Shuichi; Nakamura, Yasuyuki; Fujie, Gou; Arai, Ryuta; Miura, Seiichi

2017-10-01

The characteristics of the oceanic Moho are known to depend on various factors, such as seafloor spreading rate, crustal age, and accretionary processes at a ridge. However, the effect of local magmatic activities on the seismic signature of the Moho is poorly understood. Here an active-source reflection and refraction survey is used to investigate crustal structure and Moho characteristics along a >1000-km-long profile southeast of the Shatsky Rise in a Pacific Ocean basin formed from the Late Jurassic to Early Cretaceous and spanning the onset of Shatsky Rise volcanism. Although the seismic velocity structure estimated from the refraction data showed typical characteristics of the oceanic crust of the old Pacific plate, the appearance of the Moho reflections was spatially variable. We observed clear Moho reflections such as those to be expected where the spreading rate is fast to intermediate only at the southwestern end of the profile, whereas Moho reflections were diffuse, weak, or absent along other parts of the profile. The poor Moho reflections can be explained by the presence of a thick crust-mantle transition layer, which is temporally coincident with the formation of the Shatsky Rise. We inferred that the crust-mantle transition layer was formed by changes in on-axis accretion process or modification of the primary Moho by off-axis magmatism, induced by magmatic activity of the Shatsky Rise.

Seasonal and Diel Activity Patterns of Eight Sympatric Mammals in Northern Japan Revealed by an Intensive Camera-Trap Survey.

Directory of Open Access Journals (Sweden)

Takashi Ikeda

Full Text Available The activity patterns of mammals are generally categorized as nocturnal, diurnal, crepuscular (active at twilight, and cathemeral (active throughout the day. These patterns are highly variable across regions and seasons even within the same species. However, quantitative data is still lacking, particularly for sympatric species. We monitored the seasonal and diel activity patterns of terrestrial mammals in Hokkaido, Japan. Through an intensive camera-trap survey a total of 13,279 capture events were recorded from eight mammals over 20,344 camera-trap days, i.e., two years. Diel activity patterns were clearly divided into four categories: diurnal (Eurasian red squirrels, nocturnal (raccoon dogs and raccoons, crepuscular (sika deer and mountain hares, and cathemeral (Japanese martens, red foxes, and brown bears. Some crepuscular and cathemeral mammals shifted activity peaks across seasons. Particularly, sika deer changed peaks from twilight during spring-autumn to day-time in winter, possibly because of thermal constraints. Japanese martens were cathemeral during winter-summer, but nocturnal in autumn. We found no clear indication of predator-prey and competitive interactions, suggesting that animal densities are not very high or temporal niche partitioning is absent among the target species. This long-term camera-trap survey was highly cost-effective and provided one of the most detailed seasonal and diel activity patterns in multiple sympatric mammals under natural conditions.

Bibliometric Analyses Reveal Patterns of Collaboration between ASMS Members

Science.gov (United States)

Palmblad, Magnus; van Eck, Nees Jan

2018-03-01

We have explored the collaborative network of the current American Society for Mass Spectrometry (ASMS) membership using bibliometric methods. The analysis shows that 4249 members are connected in a single, large, co-authorship graph, including the majority of the most published authors in the field of mass spectrometry. The map reveals topographical differences between university groups and national laboratories, and that the co-authors with the strongest links have long worked together at the same location. We have collected and summarized information on the geographical distribution of members, showing a high coverage of active researchers in North America and Western Europe. Looking at research fields, we could also identify a number of new or `hot' topics among ASMS members. Interactive versions of the maps are available on-line at https://goo.gl/UBNFMQ (collaborative network) and https://goo.gl/WV25vm (research topics). [Figure not available: see fulltext.

Social cognitive correlates of leisure time physical activity among Latinos.

Science.gov (United States)

Marquez, David X; McAuley, Edward

2006-06-01

Despite the well-documented benefits of leisure time physical activity, Latinos are reported to be highest among all ethnic groups in leisure time inactivity. The present study examined the relationship between leisure time physical activity and exercise self-efficacy, exercise barriers self-efficacy, exercise social support, and perceived importance of physical activity. Data were obtained from 153 Latinos (n = 86 female, n = 67 male). Comparisons were made between Latinos with high and low levels of leisure time physical activity and between men and women. Results revealed that Latinos high in leisure time physical activity had significantly greater exercise and barriers self-efficacy, received more social support from friends to exercise, and placed greater importance on physical activity outcomes than did Latinos low in leisure time physical activity. No significant differences were revealed for social support from family, nor between men and women on the psychosocial variables. Physical activity interventions targeting sources of self-efficacy, increasing social support, and emphasizing the importance of regular physical activity should be helpful in increasing leisure time physical activity of Latinos. Future research should examine the influence of environmental and cultural variables on the leisure time physical activity of Latinos and how they interact with psychosocial factors.

Nullspace Sampling with Holonomic Constraints Reveals Molecular Mechanisms of Protein Gαs.

Directory of Open Access Journals (Sweden)

Dimitar V Pachov

2015-07-01

Full Text Available Proteins perform their function or interact with partners by exchanging between conformational substates on a wide range of spatiotemporal scales. Structurally characterizing these exchanges is challenging, both experimentally and computationally. Large, diffusional motions are often on timescales that are difficult to access with molecular dynamics simulations, especially for large proteins and their complexes. The low frequency modes of normal mode analysis (NMA report on molecular fluctuations associated with biological activity. However, NMA is limited to a second order expansion about a minimum of the potential energy function, which limits opportunities to observe diffusional motions. By contrast, kino-geometric conformational sampling (KGS permits large perturbations while maintaining the exact geometry of explicit conformational constraints, such as hydrogen bonds. Here, we extend KGS and show that a conformational ensemble of the α subunit Gαs of heterotrimeric stimulatory protein Gs exhibits structural features implicated in its activation pathway. Activation of protein Gs by G protein-coupled receptors (GPCRs is associated with GDP release and large conformational changes of its α-helical domain. Our method reveals a coupled α-helical domain opening motion while, simultaneously, Gαs helix α5 samples an activated conformation. These motions are moderated in the activated state. The motion centers on a dynamic hub near the nucleotide-binding site of Gαs, and radiates to helix α4. We find that comparative NMA-based ensembles underestimate the amplitudes of the motion. Additionally, the ensembles fall short in predicting the accepted direction of the full activation pathway. Taken together, our findings suggest that nullspace sampling with explicit, holonomic constraints yields ensembles that illuminate molecular mechanisms involved in GDP release and protein Gs activation, and further establish conformational coupling between key

Open source data reveals connection between online and on-street protest activity.

Science.gov (United States)

Qi, Hong; Manrique, Pedro; Johnson, Daniela; Restrepo, Elvira; Johnson, Neil F

There is enormous interest in inferring features of human behavior in the real world from potential digital footprints created online - particularly at the collective level, where the sheer volume of online activity may indicate some changing mood within the population regarding a particular topic. Civil unrest is a prime example, involving the spontaneous appearance of large crowds of otherwise unrelated people on the street on a certain day. While indicators of brewing protests might be gleaned from individual online communications or account content (e.g. Twitter, Facebook) societal concerns regarding privacy can make such probing a politically delicate issue. Here we show that instead, a simple low-level indicator of civil unrest can be obtained from online data at the aggregate level through Google Trends or similar tools. Our study covers countries across Latin America during 2011-2014 in which diverse civil unrest events took place. In each case, we find that the combination of the volume and momentum of searches from Google Trends surrounding pairs of simple keywords, tailored for the specific cultural setting, provide good indicators of periods of civil unrest. This proof-of-concept study motivates the search for more geographically specific indicators based on geo-located searches at the urban level.

Activity of pyramidal I and II slip in Mg alloys as revealed by texture development

Science.gov (United States)

Zecevic, Miroslav; Beyerlein, Irene J.; Knezevic, Marko

2018-02-01

Due to the geometry of the hexagonal close-packed (HCP) lattice, there are two types of pyramidal slip modes: { 10 1 bar 1 } 〈 11 2 bar 3 bar 〉 or type I and { 1 bar 1 bar 22 } 〈 11 2 bar 3 〉 or type II in HCP crystalline materials. Here we use crystal plasticity to examine the importance of crystallographic slip by pyramidal type I and type II on texture evolution. The study is applied to an Mg-4%Li alloy. An elastic-plastic polycrystal model is employed to elucidate the reorientation tendencies of these two slip modes in rolling of a textured polycrystal. Comparisons with experimental texture measurements indicate that both pyramidal I and II type slip were active during rolling deformation, with pyramidal I being the dominant mode. A single-slip-mode analysis is used to identify the orientations that prefer pyramidal I vs. II type slip when acting alone in a crystal. The analysis applies not only to Mg-4%Li, but identifies the key texture components in HCP crystals that would help distinguish the activity of pyramidal I from pyramidal II slip in rolling deformation.

Age Specifics of Cognitive Activity Development in Preschool Age

OpenAIRE

Klopotova E.E.; Samkova I.A.

2017-01-01

This paper present results of the research on the specifics of cognitive activity development in preschool children. The hypothesis tested was that content and dynamic components of cognitive activity reveal themselves in a different way depending on the stage of preschool childhood. The authors reviewed the diagnostic tools suitable for studying cognitive activity in preschoolers and selected the techniques. The research proved that content and dynamic components of cognitive activity have t...

Transcriptional Activities of the Microbial Consortium Living with the Marine Nitrogen-Fixing Cyanobacterium Trichodesmium Reveal Potential Roles in Community-Level Nitrogen Cycling.

Science.gov (United States)

Lee, Michael D; Webb, Eric A; Walworth, Nathan G; Fu, Fei-Xue; Held, Noelle A; Saito, Mak A; Hutchins, David A

2018-01-01

Trichodesmium is a globally distributed cyanobacterium whose nitrogen-fixing capability fuels primary production in warm oligotrophic oceans. Like many photoautotrophs, Trichodesmium serves as a host to various other microorganisms, yet little is known about how this associated community modulates fluxes of environmentally relevant chemical species into and out of the supraorganismal structure. Here, we utilized metatranscriptomics to examine gene expression activities of microbial communities associated with Trichodesmium erythraeum (strain IMS101) using laboratory-maintained enrichment cultures that have previously been shown to harbor microbial communities similar to those of natural populations. In enrichments maintained under two distinct CO 2 concentrations for ∼8 years, the community transcriptional profiles were found to be specific to the treatment, demonstrating a restructuring of overall gene expression had occurred. Some of this restructuring involved significant increases in community respiration-related transcripts under elevated CO 2 , potentially facilitating the corresponding measured increases in host nitrogen fixation rates. Particularly of note, in both treatments, community transcripts involved in the reduction of nitrate, nitrite, and nitrous oxide were detected, suggesting the associated organisms may play a role in colony-level nitrogen cycling. Lastly, a taxon-specific analysis revealed distinct ecological niches of consistently cooccurring major taxa that may enable, or even encourage, the stable cohabitation of a diverse community within Trichodesmium consortia. IMPORTANCE Trichodesmium is a genus of globally distributed, nitrogen-fixing marine cyanobacteria. As a source of new nitrogen in otherwise nitrogen-deficient systems, these organisms help fuel carbon fixation carried out by other more abundant photoautotrophs and thereby have significant roles in global nitrogen and carbon cycling. Members of the Trichodesmium genus tend to

Mass Spectrometry Imaging Reveals Elevated Glomerular ATP/AMP in Diabetes/obesity and Identifies Sphingomyelin as a Possible Mediator

Directory of Open Access Journals (Sweden)

Satoshi Miyamoto

2016-05-01

Full Text Available AMP-activated protein kinase (AMPK is suppressed in diabetes and may be due to a high ATP/AMP ratio, however the quantitation of nucleotides in vivo has been extremely difficult. Via matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI to localize renal nucleotides we found that the diabetic kidney had a significant increase in glomerular ATP/AMP ratio. Untargeted MALDI-MSI analysis revealed that a specific sphingomyelin species (SM(d18:1/16:0 accumulated in the glomeruli of diabetic and high-fat diet-fed mice compared with wild-type controls. In vitro studies in mesangial cells revealed that exogenous addition of SM(d18:1/16:0 significantly elevated ATP via increased glucose consumption and lactate production with a consequent reduction of AMPK and PGC1α. Furthermore, inhibition of sphingomyelin synthases reversed these effects. Our findings suggest that AMPK is reduced in the diabetic kidney due to an increase in the ATP/AMP ratio and that SM(d18:1/16:0 could be responsible for the enhanced ATP production via activation of the glycolytic pathway.

Revealing Pathway Dynamics in Heart Diseases by Analyzing Multiple Differential Networks.

Directory of Open Access Journals (Sweden)

Xiaoke Ma

2015-06-01

Full Text Available Development of heart diseases is driven by dynamic changes in both the activity and connectivity of gene pathways. Understanding these dynamic events is critical for understanding pathogenic mechanisms and development of effective treatment. Currently, there is a lack of computational methods that enable analysis of multiple gene networks, each of which exhibits differential activity compared to the network of the baseline/healthy condition. We describe the iMDM algorithm to identify both unique and shared gene modules across multiple differential co-expression networks, termed M-DMs (multiple differential modules. We applied iMDM to a time-course RNA-Seq dataset generated using a murine heart failure model generated on two genotypes. We showed that iMDM achieves higher accuracy in inferring gene modules compared to using single or multiple co-expression networks. We found that condition-specific M-DMs exhibit differential activities, mediate different biological processes, and are enriched for genes with known cardiovascular phenotypes. By analyzing M-DMs that are present in multiple conditions, we revealed dynamic changes in pathway activity and connectivity across heart failure conditions. We further showed that module dynamics were correlated with the dynamics of disease phenotypes during the development of heart failure. Thus, pathway dynamics is a powerful measure for understanding pathogenesis. iMDM provides a principled way to dissect the dynamics of gene pathways and its relationship to the dynamics of disease phenotype. With the exponential growth of omics data, our method can aid in generating systems-level insights into disease progression.

Spores of many common airborne fungi reveal no ice nucleation activity in oil immersion freezing experiments

Science.gov (United States)

Pummer, B. G.; Atanasova, L.; Bauer, H.; Bernardi, J.; Druzhinina, I. S.; Fröhlich-Nowoisky, J.; Grothe, H.

2013-12-01

Fungal spores are ubiquitous biological aerosols, which are considered to act as ice nuclei. In this study the ice nucleation (IN) activity of spores harvested from 29 fungal strains belonging to 21 different species was tested in the immersion freezing mode by microscopic observation of water-in-oil emulsions. Spores of 8 of these strains were also investigated in a microdroplet freezing array instrument. The focus was laid on species of economical, ecological or sanitary significance. Besides common molds (Ascomycota), some representatives of the widespread group of mushrooms (Basidiomycota) were also investigated. Fusarium avenaceum was the only sample showing IN activity at relatively high temperatures (about 264 K), while the other investigated fungal spores showed no freezing above 248 K. Many of the samples indeed froze at homogeneous ice nucleation temperatures (about 237 K). In combination with other studies, this suggests that only a limited number of species may act as atmospheric ice nuclei. This would be analogous to what is already known for the bacterial ice nuclei. Apart from that, we selected a set of fungal strains from different sites and exposed them to occasional freezing stress during their cultivation. This was in order to test if the exposure to a cold environment encourages the expression of ice nuclei during growth as a way of adaptation. Although the total protein expression was altered by this treatment, it had no significant impact on the IN activity.

High Pressure ZZ-Exchange NMR Reveals Key Features of Protein Folding Transition States.

Science.gov (United States)

Zhang, Yi; Kitazawa, Soichiro; Peran, Ivan; Stenzoski, Natalie; McCallum, Scott A; Raleigh, Daniel P; Royer, Catherine A

2016-11-23

Understanding protein folding mechanisms and their sequence dependence requires the determination of residue-specific apparent kinetic rate constants for the folding and unfolding reactions. Conventional two-dimensional NMR, such as HSQC experiments, can provide residue-specific information for proteins. However, folding is generally too fast for such experiments. ZZ-exchange NMR spectroscopy allows determination of folding and unfolding rates on much faster time scales, yet even this regime is not fast enough for many protein folding reactions. The application of high hydrostatic pressure slows folding by orders of magnitude due to positive activation volumes for the folding reaction. We combined high pressure perturbation with ZZ-exchange spectroscopy on two autonomously folding protein domains derived from the ribosomal protein, L9. We obtained residue-specific apparent rates at 2500 bar for the N-terminal domain of L9 (NTL9), and rates at atmospheric pressure for a mutant of the C-terminal domain (CTL9) from pressure dependent ZZ-exchange measurements. Our results revealed that NTL9 folding is almost perfectly two-state, while small deviations from two-state behavior were observed for CTL9. Both domains exhibited large positive activation volumes for folding. The volumetric properties of these domains reveal that their transition states contain most of the internal solvent excluded voids that are found in the hydrophobic cores of the respective native states. These results demonstrate that by coupling it with high pressure, ZZ-exchange can be extended to investigate a large number of protein conformational transitions.

Search for the return of activity in active asteroid 176P/LINEAR

Energy Technology Data Exchange (ETDEWEB)

Hsieh, Henry H. [Institute for Astronomy and Astrophysics, Academia Sinica, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan (China); Denneau, Larry; Jedicke, Robert; Kaluna, Heather M.; Keane, Jacqueline V.; Kleyna, Jan; MacLennan, Eric M.; Meech, Karen J.; Riesen, Timm; Schunova, Eva; Urban, Laurie; Vereš, Peter; Wainscoat, Richard J. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Fitzsimmons, Alan; Lacerda, Pedro [Astrophysics Research Centre, Queens University Belfast, Belfast BT7 1NN (United Kingdom); Hainaut, Olivier R. [European Southern Observatory, Karl-Schwarzschild-Straße 2, D-85748 Garching bei München (Germany); Ishiguro, Masateru [Department of Physics and Astronomy, Seoul National University, 599 Gwanak-ro, Gwanak, Seoul 151-742 (Korea, Republic of); Moskovitz, Nick A. [Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Snodgrass, Colin [Max-Planck-Institut für Sonnensystemforschung, Max-Planck-Str. 2, D-37191 Katlenburg-Lindau (Germany); Trujillo, Chadwick A., E-mail: hhsieh@asiaa.sinica.edu.tw [Gemini Observatory, Northern Operations Center, 670 North Aohoku Place, Hilo, HI 96720 (United States); and others

2014-04-01

We present the results of a search for the reactivation of active asteroid 176P/LINEAR during its 2011 perihelion passage using deep optical observations obtained before, during, and after that perihelion passage. Deep composite images of 176P constructed from data obtained between 2011 June and 2011 December show no visible signs of activity, while photometric measurements of the object during this period also show no significant brightness enhancements similar to that observed for 176P between 2005 November and 2005 December when it was previously observed to be active. An azimuthal search for dust emission likewise reveals no evidence for directed emission (i.e., a tail, as was previously observed for 176P), while a one-dimensional surface brightness profile analysis shows no indication of a spherically symmetric coma at any time in 2011. We conclude that 176P did not in fact exhibit activity in 2011, at least not on the level on which it exhibited activity in 2005, and suggest that this could be due to the devolatization or mantling of the active site responsible for its activity in 2005.

Role Performance of Social Institutions in Student Activities

Directory of Open Access Journals (Sweden)

Helen R. Lara

2017-02-01

Full Text Available The study was conducted to determine the influence of social institutions on the involvement of students in school activities. The descriptive method of research was used. Purposive sampling was utilized which involved 30 Presidents of all accredited student organizations. The study specifically determined the degree of involvement of students in school activities; and identified the roles of social institutions and the extent of their influence on the involvement of students in college activities. Interviews, documentary analysis and a survey using a questionnaire-checklist were utilized to gather data and information. The study revealed that family and school have a strong influence on the participation of students in school activities. This was so because student leaders are often in direct contact with people who provide support and spend a long time with them. The Church and community are revealed as moderate influences. The moderate influence of social institutions is because students are not exposed to a variety of activities that are equally important in the development of their abilities and skills. It was found that students had limited involvement in church and community undertakings because of the demands put upon them by their academic and non-academic school activities. There is a need to improve students’ participation in the Church and community activities that have moderate influence in order to strengthen their roles

Modelling reveals kinetic advantages of co-transcriptional splicing.

Directory of Open Access Journals (Sweden)

Stuart Aitken

2011-10-01

Full Text Available Messenger RNA splicing is an essential and complex process for the removal of intron sequences. Whereas the composition of the splicing machinery is mostly known, the kinetics of splicing, the catalytic activity of splicing factors and the interdependency of transcription, splicing and mRNA 3' end formation are less well understood. We propose a stochastic model of splicing kinetics that explains data obtained from high-resolution kinetic analyses of transcription, splicing and 3' end formation during induction of an intron-containing reporter gene in budding yeast. Modelling reveals co-transcriptional splicing to be the most probable and most efficient splicing pathway for the reporter transcripts, due in part to a positive feedback mechanism for co-transcriptional second step splicing. Model comparison is used to assess the alternative representations of reactions. Modelling also indicates the functional coupling of transcription and splicing, because both the rate of initiation of transcription and the probability that step one of splicing occurs co-transcriptionally are reduced, when the second step of splicing is abolished in a mutant reporter.

Modelling reveals kinetic advantages of co-transcriptional splicing.

Science.gov (United States)

Aitken, Stuart; Alexander, Ross D; Beggs, Jean D

2011-10-01

Messenger RNA splicing is an essential and complex process for the removal of intron sequences. Whereas the composition of the splicing machinery is mostly known, the kinetics of splicing, the catalytic activity of splicing factors and the interdependency of transcription, splicing and mRNA 3' end formation are less well understood. We propose a stochastic model of splicing kinetics that explains data obtained from high-resolution kinetic analyses of transcription, splicing and 3' end formation during induction of an intron-containing reporter gene in budding yeast. Modelling reveals co-transcriptional splicing to be the most probable and most efficient splicing pathway for the reporter transcripts, due in part to a positive feedback mechanism for co-transcriptional second step splicing. Model comparison is used to assess the alternative representations of reactions. Modelling also indicates the functional coupling of transcription and splicing, because both the rate of initiation of transcription and the probability that step one of splicing occurs co-transcriptionally are reduced, when the second step of splicing is abolished in a mutant reporter.

Activated carbon derived from marine Posidonia Oceanica for electric energy storage

Directory of Open Access Journals (Sweden)

N. Boukmouche

2014-07-01

Full Text Available In this paper, the synthesis and characterization of activated carbon from marine Posidonia Oceanica were studied. The activated carbon was prepared by a simple process namely pyrolysis under inert atmosphere. The activated carbon can be used as electrodes for supercapacitor devices. X-ray diffraction result revealed a polycrystalline graphitic structure. While scanning electron microscope investigation showed a layered structure with micropores. The EDS analysis showed that the activated carbon contains the carbon element in high atomic percentage. Electrochemical impedance spectroscopy revealed a capacitive behavior (electrostatic phenomena. The specific capacity per unit area of the electrochemical double layer of activated carbon electrode in sulfuric acid electrolyte was 3.16 F cm−2. Cyclic voltammetry and galvanostatic chronopotentiometry demonstrated that the electrode has excellent electrochemical reversibility. It has been found that the surface capacitance was strongly related to the specific surface area and pore size.

Revealed preference with limited consideration

NARCIS (Netherlands)

Demuynck, T.; Seel, C.

2014-01-01

We derive revealed preference tests for models where individuals use consideration sets to simplify their consumption problem. Our basic test provides necessary and sufficient conditions for consistency of observed choices with the existence of consideration set restrictions. The same conditions can

TypeScript revealed

CERN Document Server

Maharry, Dan

2013-01-01

TypeScript Revealed is a quick 100-page guide to Anders Hejlsberg's new take on JavaScript. With this brief, fast-paced introduction to TypeScript, .NET, Web and Windows 8 application developers who are already familiar with JavaScript will easily get up to speed with TypeScript and decide whether or not to start incorporating it into their own development. TypeScript is 'JavaScript for Application-scale development'; a superset of JavaScript that brings to it an additional object-oriented-like syntax familiar to .NET programmers that compiles down into simple, clean JavaScript that any browse

Canada's Physical Activity Guide: examining print-based material for motivating physical activity in the workplace.

Science.gov (United States)

Plotnikoff, Ronald C; Todosijczuk, Ivan; Johnson, Steven T; Karunamuni, Nandini

2012-01-01

The authors conducted a secondary analysis on 202 adults from the Physical Activity Workplace Study. The aim of this analysis was to examine demographic characteristics associated with reading Canada's Physical Activity Guide (CPAG), being motivated by the guide, and whether participants in the Physical Activity Workplace Study who read the CPAG increased their physical activity levels over 1 year. Results revealed that less than 50% of participants read the full version of CPAG, and less than 10% were motivated by it. The CPAG also appears to be more appealing to and effective for women than for men. Although the CPAG had some influence in increasing mild physical activity levels in a workplace sample, there was also a decrease in physical activity levels among some members of the group. Overall, the effectiveness of CPAG was not substantial, and the findings of this analysis could help guide future targeted intervention materials and programs.

Explaining Physical Activity in Children with Visual Impairments: A Family Systems Approach

Science.gov (United States)

Ayvazoglu, Nalan R.; Oh, Hyun-Kyoung; Kozub, Francis M.

2006-01-01

Using a mixed design this study explored physical activity in children with visual impairments from a family perspective. Quantitative findings revealed varied amounts of physical activity; younger children were more active than older participants. Further, parents were involved in moderate to vigorous physical activity 0% to 21% of the time when…

Intersubject information mapping: revealing canonical representations of complex natural stimuli

Directory of Open Access Journals (Sweden)

Nikolaus Kriegeskorte

2015-03-01

Full Text Available Real-world time-continuous stimuli such as video promise greater naturalism for studies of brain function. However, modeling the stimulus variation is challenging and introduces a bias in favor of particular descriptive dimensions. Alternatively, we can look for brain regions whose signal is correlated between subjects, essentially using one subject to model another. Intersubject correlation mapping (ICM allows us to find brain regions driven in a canonical manner across subjects by a complex natural stimulus. However, it requires a direct voxel-to-voxel match between the spatiotemporal activity patterns and is thus only sensitive to common activations sufficiently extended to match up in Talairach space (or in an alternative, e.g. cortical-surface-based, common brain space. Here we introduce the more general approach of intersubject information mapping (IIM. For each brain region, IIM determines how much information is shared between the subjects' local spatiotemporal activity patterns. We estimate the intersubject mutual information using canonical correlation analysis applied to voxels within a spherical searchlight centered on each voxel in turn. The intersubject information estimate is invariant to linear transforms including spatial rearrangement of the voxels within the searchlight. This invariance to local encoding will be crucial in exploring fine-grained brain representations, which cannot be matched up in a common space and, more fundamentally, might be unique to each individual – like fingerprints. IIM yields a continuous brain map, which reflects intersubject information in fine-grained patterns. Performed on data from functional magnetic resonance imaging (fMRI of subjects viewing the same television show, IIM and ICM both highlighted sensory representations, including primary visual and auditory cortices. However, IIM revealed additional regions in higher association cortices, namely temporal pole and orbitofrontal cortex. These

Single molecule analysis of c-myb alternative splicing reveals novel classifiers for precursor B-ALL.

Directory of Open Access Journals (Sweden)

Ye E Zhou

Full Text Available The c-Myb transcription factor, a key regulator of proliferation and differentiation in hematopoietic and other cell types, has an N-terminal DNA binding domain and a large C-terminal domain responsible for transcriptional activation, negative regulation and determining target gene specificity. Overexpression and rearrangement of the c-myb gene (MYB has been reported in some patients with leukemias and other types of cancers, implicating activated alleles of c-myb in the development of human tumors. Alternative RNA splicing can produce variants of c-myb with qualitatively distinct transcriptional activities that may be involved in transformation and leukemogenesis. Here, by performing a detailed, single molecule assay we found that c-myb alternative RNA splicing was elevated and much more complex in leukemia samples than in cell lines or CD34+ hematopoietic progenitor cells from normal donors. The results revealed that leukemia samples express more than 60 different c-myb splice variants, most of which have multiple alternative splicing events and were not detectable by conventional microarray or PCR approaches. For example, the single molecule assay detected 21 and 22 splice variants containing the 9B and 9S exons, respectively, most of which encoded unexpected variant forms of c-Myb protein. Furthermore, the detailed analysis identified some splice variants whose expression correlated with poor survival in a small cohort of precursor B-ALL samples. Our findings indicate that single molecule assays can reveal complexities in c-myb alternative splicing that have potential as novel biomarkers and could help explain the role of c-Myb variants in the development of human leukemia.

Screening Bioactives Reveals Nanchangmycin as a Broad Spectrum Antiviral Active against Zika Virus

Directory of Open Access Journals (Sweden)

Keiko Rausch

2017-01-01

Full Text Available Zika virus is an emerging arthropod-borne flavivirus for which there are no vaccines or specific therapeutics. We screened a library of 2,000 bioactive compounds for their ability to block Zika virus infection in three distinct cell types with two different strains of Zika virus. Using a microscopy-based assay, we validated 38 drugs that inhibited Zika virus infection, including FDA-approved nucleoside analogs. Cells expressing high levels of the attachment factor AXL can be protected from infection with receptor tyrosine kinase inhibitors, while placental-derived cells that lack AXL expression are insensitive to this inhibition. Importantly, we identified nanchangmycin as a potent inhibitor of Zika virus entry across all cell types tested, including physiologically relevant primary cells. Nanchangmycin also was active against other medically relevant viruses, including West Nile, dengue, and chikungunya viruses that use a similar route of entry. This study provides a resource of small molecules to study Zika virus pathogenesis.

Computational redesign reveals allosteric mutation hotspots of organophosphate hydrolase that enhance organophosphate hydrolysis

Energy Technology Data Exchange (ETDEWEB)

Jacob, Reed B. [Univ. of North Carolina, Chapel Hill, NC (United States); Ding, Feng [Clemson Univ., SC (United States); Ye, Dongmei [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ackerman, Eric [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Dokholyan, Nikolay V. [Univ. of North Carolina, Chapel Hill, NC (United States)

2015-04-01

Organophosphates are widely used for peaceful (agriculture) and military purposes (chemical warfare agents). The extraordinary toxicity of organophosphates and the risk of deployment, make it critical to develop means for their rapid and efficient deactivation. Organophosphate hydrolase (OPH) already plays an important role in organophosphate remediation, but is insufficient for therapeutic or prophylactic purposes primarily due to low substrate affinity. Current efforts focus on directly modifying the active site to differentiate substrate specificity and increase catalytic activity. Here, we present a novel strategy for enhancing the general catalytic efficiency of OPH through computational redesign of the residues that are allosterically coupled to the active site and validated our design by mutagenesis. Specifically, we identify five such hot-spot residues for allosteric regulation and assay these mutants for hydrolysis activity against paraoxon, a chemical-weapons simulant. A high percentage of the predicted mutants exhibit enhanced activity over wild-type (k_cat =16.63 s^-1), such as T199I/T54I (899.5 s^-1) and C227V/T199I/T54I (848 s^-1), while the Km remains relatively unchanged in our high-throughput cell-free expression system. Further computational studies of protein dynamics reveal four distinct distal regions coupled to the active site that display significant changes in conformation dynamics upon these identified mutations. These results validate a computational design method that is both efficient and easily adapted as a general procedure for enzymatic enhancement.

Vocal Tract Images Reveal Neural Representations of Sensorimotor Transformation During Speech Imitation

Science.gov (United States)

Carey, Daniel; Miquel, Marc E.; Evans, Bronwen G.; Adank, Patti; McGettigan, Carolyn

2017-01-01

Abstract Imitating speech necessitates the transformation from sensory targets to vocal tract motor output, yet little is known about the representational basis of this process in the human brain. Here, we address this question by using real-time MR imaging (rtMRI) of the vocal tract and functional MRI (fMRI) of the brain in a speech imitation paradigm. Participants trained on imitating a native vowel and a similar nonnative vowel that required lip rounding. Later, participants imitated these vowels and an untrained vowel pair during separate fMRI and rtMRI runs. Univariate fMRI analyses revealed that regions including left inferior frontal gyrus were more active during sensorimotor transformation (ST) and production of nonnative vowels, compared with native vowels; further, ST for nonnative vowels activated somatomotor cortex bilaterally, compared with ST of native vowels. Using test representational similarity analysis (RSA) models constructed from participants’ vocal tract images and from stimulus formant distances, we found that RSA searchlight analyses of fMRI data showed either type of model could be represented in somatomotor, temporal, cerebellar, and hippocampal neural activation patterns during ST. We thus provide the first evidence of widespread and robust cortical and subcortical neural representation of vocal tract and/or formant parameters, during prearticulatory ST. PMID:28334401

Vesicular trafficking of immune mediators in human eosinophils revealed by immunoelectron microscopy

Energy Technology Data Exchange (ETDEWEB)

Melo, Rossana C.N., E-mail: rossana.melo@ufjf.edu.br [Laboratory of Cellular Biology, Department of Biology, ICB, Federal University of Juiz de Fora, UFJF, Rua José Lourenço Kelmer, Juiz de Fora, MG 36036-900 (Brazil); Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, CLS 943, Boston, MA 02215 (United States); Weller, Peter F. [Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, CLS 943, Boston, MA 02215 (United States)

2016-10-01

Electron microscopy (EM)-based techniques are mostly responsible for our current view of cell morphology at the subcellular level and continue to play an essential role in biological research. In cells from the immune system, such as eosinophils, EM has helped to understand how cells package and release mediators involved in immune responses. Ultrastructural investigations of human eosinophils enabled visualization of secretory processes in detail and identification of a robust, vesicular trafficking essential for the secretion of immune mediators via a non-classical secretory pathway associated with secretory (specific) granules. This vesicular system is mainly organized as large tubular-vesicular carriers (Eosinophil Sombrero Vesicles – EoSVs) actively formed in response to cell activation and provides a sophisticated structural mechanism for delivery of granule-stored mediators. In this review, we highlight the application of EM techniques to recognize pools of immune mediators at vesicular compartments and to understand the complex secretory pathway within human eosinophils involved in inflammatory and allergic responses. - Highlights: • Application of EM to understand the complex secretory pathway in human eosinophils. • EM techniques reveal an active vesicular system associated with secretory granules. • Tubular vesicles are involved in the transport of granule-derived immune mediators.

Vesicular trafficking of immune mediators in human eosinophils revealed by immunoelectron microscopy

International Nuclear Information System (INIS)

Melo, Rossana C.N.; Weller, Peter F.

2016-01-01

Electron microscopy (EM)-based techniques are mostly responsible for our current view of cell morphology at the subcellular level and continue to play an essential role in biological research. In cells from the immune system, such as eosinophils, EM has helped to understand how cells package and release mediators involved in immune responses. Ultrastructural investigations of human eosinophils enabled visualization of secretory processes in detail and identification of a robust, vesicular trafficking essential for the secretion of immune mediators via a non-classical secretory pathway associated with secretory (specific) granules. This vesicular system is mainly organized as large tubular-vesicular carriers (Eosinophil Sombrero Vesicles – EoSVs) actively formed in response to cell activation and provides a sophisticated structural mechanism for delivery of granule-stored mediators. In this review, we highlight the application of EM techniques to recognize pools of immune mediators at vesicular compartments and to understand the complex secretory pathway within human eosinophils involved in inflammatory and allergic responses. - Highlights: • Application of EM to understand the complex secretory pathway in human eosinophils. • EM techniques reveal an active vesicular system associated with secretory granules. • Tubular vesicles are involved in the transport of granule-derived immune mediators.

Phytochemical Screening, Antibacterial and Toxicological Activities ...

African Journals Online (AJOL)

The phytochemical screening, antibacterial and toxicological activities of extracts of the stem bark of Acacia senegal were investigated. The phytochemical analyses according to standard screening tests using conventional protocols revealed the presence of tannins, saponins and sterols in the stem bark of the plant.

Draft whole genome sequence of groundnut stem rot fungus Athelia rolfsii revealing genetic architect of its pathogenicity and virulence.

Science.gov (United States)

Iquebal, M A; Tomar, Rukam S; Parakhia, M V; Singla, Deepak; Jaiswal, Sarika; Rathod, V M; Padhiyar, S M; Kumar, Neeraj; Rai, Anil; Kumar, Dinesh

2017-07-13

Groundnut (Arachis hypogaea L.) is an important oil seed crop having major biotic constraint in production due to stem rot disease caused by fungus, Athelia rolfsii causing 25-80% loss in productivity. As chemical and biological combating strategies of this fungus are not very effective, thus genome sequencing can reveal virulence and pathogenicity related genes for better understanding of the host-parasite interaction. We report draft assembly of Athelia rolfsii genome of ~73 Mb having 8919 contigs. Annotation analysis revealed 16830 genes which are involved in fungicide resistance, virulence and pathogenicity along with putative effector and lethal genes. Secretome analysis revealed CAZY genes representing 1085 enzymatic genes, glycoside hydrolases, carbohydrate esterases, carbohydrate-binding modules, auxillary activities, glycosyl transferases and polysaccharide lyases. Repeat analysis revealed 11171 SSRs, LTR, GYPSY and COPIA elements. Comparative analysis with other existing ascomycotina genome predicted conserved domain family of WD40, CYP450, Pkinase and ABC transporter revealing insight of evolution of pathogenicity and virulence. This study would help in understanding pathogenicity and virulence at molecular level and development of new combating strategies. Such approach is imperative in endeavour of genome based solution in stem rot disease management leading to better productivity of groundnut crop in tropical region of world.

The Potential for Development of Russian Youth Social Activity

Science.gov (United States)

Savotina, Nataliya

2016-01-01

The article deals with scientific and applied topicality of studying the problem of children and youth social activity. Spheres of social activity display in European tradition, in particular, the European Charter, Great Britain, have been revealed. Comparative analysis of understanding the essence of such a phenomenon in Western theories and…

ISSUES OF STATISTICAL ESTIMATION OF BANK’S ADVERTISING ACTIVITY

Directory of Open Access Journals (Sweden)

Elena A. Egorova

2013-01-01

Full Text Available The article offers methodological approach to the analysis of advertising activity of banks who allows to reveal the most effective advertising strategy to provide their high efficiency, to establish correlation connection of the size of advertising budgets with the main social and economic characteristics of bank’s activity.

Modulation of catalytic activity in multi-domain protein tyrosine phosphatases.

Directory of Open Access Journals (Sweden)

Lalima L Madan

Full Text Available Signaling mechanisms involving protein tyrosine phosphatases govern several cellular and developmental processes. These enzymes are regulated by several mechanisms which include variation in the catalytic turnover rate based on redox stimuli, subcellular localization or protein-protein interactions. In the case of Receptor Protein Tyrosine Phosphatases (RPTPs containing two PTP domains, phosphatase activity is localized in their membrane-proximal (D1 domains, while the membrane-distal (D2 domain is believed to play a modulatory role. Here we report our analysis of the influence of the D2 domain on the catalytic activity and substrate specificity of the D1 domain using two Drosophila melanogaster RPTPs as a model system. Biochemical studies reveal contrasting roles for the D2 domain of Drosophila Leukocyte antigen Related (DLAR and Protein Tyrosine Phosphatase on Drosophila chromosome band 99A (PTP99A. While D2 lowers the catalytic activity of the D1 domain in DLAR, the D2 domain of PTP99A leads to an increase in the catalytic activity of its D1 domain. Substrate specificity, on the other hand, is cumulative, whereby the individual specificities of the D1 and D2 domains contribute to the substrate specificity of these two-domain enzymes. Molecular dynamics simulations on structural models of DLAR and PTP99A reveal a conformational rationale for the experimental observations. These studies reveal that concerted structural changes mediate inter-domain communication resulting in either inhibitory or activating effects of the membrane distal PTP domain on the catalytic activity of the membrane proximal PTP domain.

Comparative analysis reveals the underlying mechanism of vertebrate seasonal reproduction.

Science.gov (United States)

Ikegami, Keisuke; Yoshimura, Takashi

2016-02-01

Animals utilize photoperiodic changes as a calendar to regulate seasonal reproduction. Birds have highly sophisticated photoperiodic mechanisms and functional genomics analysis in quail uncovered the signal transduction pathway regulating avian seasonal reproduction. Birds detect light with deep brain photoreceptors. Long day (LD) stimulus induces secretion of thyroid-stimulating hormone (TSH) from the pars tuberalis (PT) of the pituitary gland. PT-derived TSH locally activates thyroid hormone (TH) in the hypothalamus, which induces gonadotropin-releasing hormone (GnRH) and hence gonadotropin secretion. However, during winter, low temperatures increase serum TH for adaptive thermogenesis, which accelerates germ cell apoptosis by activating the genes involved in metamorphosis. Therefore, TH has a dual role in the regulation of seasonal reproduction. Studies using TSH receptor knockout mice confirmed the involvement of PT-derived TSH in mammalian seasonal reproduction. In addition, studies in mice revealed that the tissue-specific glycosylation of TSH diversifies its function in the circulation to avoid crosstalk. In contrast to birds and mammals, one of the molecular machineries necessary for the seasonal reproduction of fish are localized in the saccus vasculosus from the photoreceptor to the neuroendocrine output. Thus, comparative analysis is a powerful tool to uncover the universality and diversity of fundamental properties in various organisms. Copyright © 2015 Elsevier Inc. All rights reserved.

Revealing the cerebral regions and networks mediating vulnerability to depression: oxidative metabolism mapping of rat brain.

Science.gov (United States)

Harro, Jaanus; Kanarik, Margus; Kaart, Tanel; Matrov, Denis; Kõiv, Kadri; Mällo, Tanel; Del Río, Joaquin; Tordera, Rosa M; Ramirez, Maria J

2014-07-01

The large variety of available animal models has revealed much on the neurobiology of depression, but each model appears as specific to a significant extent, and distinction between stress response, pathogenesis of depression and underlying vulnerability is difficult to make. Evidence from epidemiological studies suggests that depression occurs in biologically predisposed subjects under impact of adverse life events. We applied the diathesis-stress concept to reveal brain regions and functional networks that mediate vulnerability to depression and response to chronic stress by collapsing data on cerebral long term neuronal activity as measured by cytochrome c oxidase histochemistry in distinct animal models. Rats were rendered vulnerable to depression either by partial serotonergic lesion or by maternal deprivation, or selected for a vulnerable phenotype (low positive affect, low novelty-related activity or high hedonic response). Environmental adversity was brought about by applying chronic variable stress or chronic social defeat. Several brain regions, most significantly median raphe, habenula, retrosplenial cortex and reticular thalamus, were universally implicated in long-term metabolic stress response, vulnerability to depression, or both. Vulnerability was associated with higher oxidative metabolism levels as compared to resilience to chronic stress. Chronic stress, in contrast, had three distinct patterns of effect on oxidative metabolism in vulnerable vs. resilient animals. In general, associations between regional activities in several brain circuits were strongest in vulnerable animals, and chronic stress disrupted this interrelatedness. These findings highlight networks that underlie resilience to stress, and the distinct response to stress that occurs in vulnerable subjects. Copyright © 2014 Elsevier B.V. All rights reserved.

Evaluation of biological activities and chemical constituent of storage medicinal plant materials used as a traditional medicine in Nepal

Directory of Open Access Journals (Sweden)

Bishnu Prasad Pandey

2017-12-01

Full Text Available Aim: The main aims of the study were to evaluate the phytochemicals, antioxidant, antibacterial and chemical constituents of storage medicinal plant materials used as a traditional medicine in Nepal. Methods: Phytochemical screening, total phenolic content, total flavonoid content, antibacterial activities, anti-oxidant assay of the crude extract (water, methanol, n-hexane and acetone were carried out to identify the biological activities and phytonutrients present in the different extract. The chemical constituents present in the crude extract were analyzed using the high performance liquid chromatography (HPLC equipped with UV detector. Results: Evaluated medicinal plant materials were found to have diverse phytonutrients. Results revealed that methanol extract of Pakhanved and Jethimadhu have highest total flavonoids and polyphenol content. Among the selected medicinal plant materials Jethimadhu extract revealed the highest antioxidant activities. Furthermore, evaluated medicinal plants extract were found to exert a range of in vitro growth inhibition activity against both gram positive and gram negative species. The highest antibacterial activities were observed in the case of methanol extract, whereas, least activity was observed with the hexane extract. HPLC analysis of the acetone extract of Jethimadhu reveals the presence of diosmetin. Conclusions: Our result revealed that among the five evaluated medicinal plant materials, Jethimadhu extract revealed biological activities and exhibits a higher amount of polyphenol and flavonoid content. [J Complement Med Res 2017; 6(4.000: 369-377

Transcriptomic variation in a coral reveals pathways of clonal organisation

DEFF Research Database (Denmark)

K Bay, Line; Nielsen, Henrik Bjørn; Jarmer, Hanne Østergaard

2009-01-01

A microarray study was undertaken to examine the potential for clonal gene expression variation in a branching reef building coral, Acropora millepora. The role of small-scale gradients in light and water flow was examined by comparing gene expression levels between branch elevation (tip and base......) and position (centre and edge) of replicate coral colonies (n=3). Analyses of variance revealed that almost 60% of variation in gene expression was present between colonies and 34 genes were considered differentially expressed between colonies (minimum P=6.5 x 10(-4)). These genes are associated with energy...... of corymbose-like branching coral colonies such as A. millepora. Four genes were differentially expressed between the tip and base of branches (P=3.239 x 10(-4)) and were associated with lysosome lipase activity and fluorescence, suggesting that branch tips may encounter higher pathogen loads or levels...

Abnormal Brain Activation During Theory of Mind Tasks in Schizophrenia: A Meta-Analysis.

Science.gov (United States)

Kronbichler, Lisa; Tschernegg, Melanie; Martin, Anna Isabel; Schurz, Matthias; Kronbichler, Martin

2017-10-21

Social cognition abilities are severely impaired in schizophrenia (SZ). The current meta-analysis used foci of 21 individual studies on functional abnormalities in the schizophrenic brain in order to identify regions that reveal convergent under- or over-activation during theory of mind (TOM) tasks. Studies were included in the analyses when contrasting tasks that require the processing of mental states with tasks which did not. Only studies that investigated patients with an ICD or DSM diagnosis were included. Quantitative voxel-based meta-analyses were done using Seed-based d Mapping software. Common TOM regions like medial-prefrontal cortex and temporo-parietal junction revealed abnormal activation in schizophrenic patients: Under-activation was identified in the medial prefrontal cortex, left orbito-frontal cortex, and in a small section of the left posterior temporo-parietal junction. Remarkably, robust over-activation was identified in a more dorsal, bilateral section of the temporo-parietal junction. Further abnormal activation was identified in medial occipito-parietal cortex, right premotor areas, left cingulate gyrus, and lingual gyrus. The findings of this study suggest that SZ patients simultaneously show over- and under-activation in TOM-related regions. Especially interesting, temporo-parietal junction reveals diverging activation patterns with an under-activating left posterior and an over-activating bilateral dorsal section. In conclusion, SZ patients show less specialized brain activation in regions linked to TOM and increased activation in attention-related networks suggesting compensatory effects. © The Author 2017. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center.

Crystal structure of the plexin A3 intracellular region reveals an autoinhibited conformation through active site sequestration

Energy Technology Data Exchange (ETDEWEB)

He, Huawei; Yang, Taehong; Terman, Jonathan R.; Zhang, Xuewu; (UTSMC)

2010-01-20

Plexin cell surface receptors bind to semaphorin ligands and transduce signals for regulating neuronal axon guidance. The intracellular region of plexins is essential for signaling and contains a R-Ras/M-Ras GTPase activating protein (GAP) domain that is divided into two segments by a Rho GTPase-binding domain (RBD). The regulation mechanisms for plexin remain elusive, although it is known that activation requires both binding of semaphorin to the extracellular region and a Rho-family GTPase (Rac1 or Rnd1) to the RBD. Here we report the crystal structure of the plexin A3 intracellular region. The structure shows that the N- and C-terminal portions of the GAP homologous regions together form a GAP domain with an overall fold similar to other Ras GAPs. However, the plexin GAP domain adopts a closed conformation and cannot accommodate R-Ras/M-Ras in its substrate-binding site, providing a structural basis for the autoinhibited state of plexins. A comparison with the plexin B1 RBD/Rnd1 complex structure suggests that Rnd1 binding alone does not induce a conformational change in plexin, explaining the requirement of both semaphorin and a Rho GTPase for activation. The structure also identifies an N-terminal segment that is important for regulation. Both the N-terminal segment and the RBD make extensive interactions with the GAP domain, suggesting the presence of an allosteric network connecting these three domains that integrates semaphorin and Rho GTPase signals to activate the GAP. The importance of these interactions in plexin signaling is shown by both cell-based and in vivo axon guidance assays.

Structure reveals regulatory mechanisms of a MaoC-like hydratase from Phytophthora capsici involved in biosynthesis of polyhydroxyalkanoates (PHAs).

Science.gov (United States)

Wang, Huizheng; Zhang, Kai; Zhu, Jie; Song, Weiwei; Zhao, Li; Zhang, Xiuguo

2013-01-01

Polyhydroxyalkanoates (PHAs) have attracted increasing attention as "green plastic" due to their biodegradable, biocompatible, thermoplastic, and mechanical properties, and considerable research has been undertaken to develop low cost/high efficiency processes for the production of PHAs. MaoC-like hydratase (MaoC), which belongs to (R)-hydratase involved in linking the β-oxidation and the PHA biosynthetic pathways, has been identified recently. Understanding the regulatory mechanisms of (R)-hydratase catalysis is critical for efficient production of PHAs that promise synthesis an environment-friendly plastic. We have determined the crystal structure of a new MaoC recognized from Phytophthora capsici. The crystal structure of the enzyme was solved at 2.00 Å resolution. The structure shows that MaoC has a canonical (R)-hydratase fold with an N-domain and a C-domain. Supporting its dimerization observed in structure, MaoC forms a stable homodimer in solution. Mutations that disrupt the dimeric MaoC result in a complete loss of activity toward crotonyl-CoA, indicating that dimerization is required for the enzymatic activity of MaoC. Importantly, structure comparison reveals that a loop unique to MaoC interacts with an α-helix that harbors the catalytic residues of MaoC. Deletion of the loop enhances the enzymatic activity of MaoC, suggesting its inhibitory role in regulating the activity of MaoC. The data in our study reveal the regulatory mechanism of an (R)-hydratase, providing information on enzyme engineering to produce low cost PHAs.

Molecular structures of viruses from Raman optical activity

DEFF Research Database (Denmark)

Blanch, Ewan W.; Hecht, Lutz; Syme, Christopher D.

2002-01-01

A vibrational Raman optical activity (ROA) study of a range of different structural types of virus exemplified by filamentous bacteriophage fd, tobacco mosaic virus, satellite tobacco mosaic virus, bacteriophage MS2 and cowpea mosaic virus has revealed that, on account of its sensitivity to chira......A vibrational Raman optical activity (ROA) study of a range of different structural types of virus exemplified by filamentous bacteriophage fd, tobacco mosaic virus, satellite tobacco mosaic virus, bacteriophage MS2 and cowpea mosaic virus has revealed that, on account of its sensitivity...... (top component) of cowpea mosaic virus from those of the intact middle and bottom-upper components separated by means of a caesium chloride density gradient, the ROA spectrum of the viral RNA was obtained, which revealed that the RNA takes up an A-type single-stranded helical conformation...... and that the RNA conformations in the middle and bottom-upper components are very similar. This information is not available from the X-ray crystal structure of cowpea mosaic virus since no nucleic acid is visible....

In silico activity profiling reveals the mechanism of action of antimalarials discovered in a high-throughput screen

Science.gov (United States)

Plouffe, David; Brinker, Achim; McNamara, Case; Henson, Kerstin; Kato, Nobutaka; Kuhen, Kelli; Nagle, Advait; Adrián, Francisco; Matzen, Jason T.; Anderson, Paul; Nam, Tae-gyu; Gray, Nathanael S.; Chatterjee, Arnab; Janes, Jeff; Yan, S. Frank; Trager, Richard; Caldwell, Jeremy S.; Schultz, Peter G.; Zhou, Yingyao; Winzeler, Elizabeth A.

2008-01-01

The growing resistance to current first-line antimalarial drugs represents a major health challenge. To facilitate the discovery of new antimalarials, we have implemented an efficient and robust high-throughput cell-based screen (1,536-well format) based on proliferation of Plasmodium falciparum (Pf) in erythrocytes. From a screen of ≈1.7 million compounds, we identified a diverse collection of ≈6,000 small molecules comprised of >530 distinct scaffolds, all of which show potent antimalarial activity (antimalarials were identified in this screen, thus validating our approach. In addition, we identified many novel chemical scaffolds, which likely act through both known and novel pathways. We further show that in some cases the mechanism of action of these antimalarials can be determined by in silico compound activity profiling. This method uses large datasets from unrelated cellular and biochemical screens and the guilt-by-association principle to predict which cellular pathway and/or protein target is being inhibited by select compounds. In addition, the screening method has the potential to provide the malaria community with many new starting points for the development of biological probes and drugs with novel antiparasitic activities. PMID:18579783

A Two-terminal Active Capacitor

DEFF Research Database (Denmark)

Wang, Haoran; Wang, Huai

2017-01-01

This letter proposes a concept of two-terminal active capacitor implemented by power semiconductor switches and passive elements. The active capacitor has the same level of convenience as a passive one with two power terminals only. It is application independent and can be specified by rated...... voltage, ripple current, equivalent series resistance, and operational frequency range. The concept, control method, self-power scheme, and impedance characteristics of the active capacitor are presented. A case study of the proposed active capacitor for a capacitive DC-link application is discussed....... The results reveal a significantly lower overall energy storage of passive elements and a reduced cost to fulfill a specific reliability target, compared to a passive capacitor solution. Proof-of-concept experimental results are given to verify the functionality of the proposed capacitor....

Life in Ice: Microbial Growth Dynamics and Greenhouse Gas Production During Winter in a Thermokarst Bog Revealed by Stable Isotope Probing Targeted Metagenomics

Science.gov (United States)

Blazewicz, S.; White, R. A., III; Tas, N.; Euskirchen, E. S.; Mcfarland, J. W.; Jansson, J.; Waldrop, M. P.

2016-12-01

Permafrost contains a reservoir of frozen C estimated to be twice the size of the current atmospheric C pool. In response to changing climate, permafrost is rapidly warming which could result in widespread seasonal thawing. When permafrost thaws, soils that are rich in ice and C often transform into thermokarst wetlands with anaerobic conditions and significant production of atmospheric CH4. While most C flux research in recently thawed permafrost concentrates on the few summer months when seasonal thaw has occurred, there is mounting evidence that sizeable portions of annual CO2 and CH4 efflux occurs over winter or during a rapid burst of emissions associated with seasonal thaw. A potential mechanism for such efflux patterns is microbial activity in frozen soils over winter where gasses produced are partially trapped within ice until spring thaw. In order to better understand microbial transformation of soil C to greenhouse gas over winter, we applied stable isotope probing (SIP) targeted metagenomics combined with process measurements and field flux data to reveal activities of microbial communities in `frozen' soil from an Alaskan thermokarst bog. Field studies revealed build-up of CO2 and CH4 in frozen soils suggesting that microbial activity persisted throughout the winter in soils poised just below the freezing point. Laboratory incubations designed to simulate in-situ winter conditions (-1.5 °C and anaerobic) revealed continuous CH4 and CO2 production. Strikingly, the quantity of CH4 produced in 6 months in frozen soil was equivalent to approximately 80% of CH4 emitted during the 3 month summer `active' season. Heavy water SIP targeted iTag sequencing revealed growing bacteria and archaea in the frozen anaerobic soil. Growth was primarily observed in two bacterial phyla, Firmicutes and Bacteroidetes, suggesting that fermentation was likely the major C mineralization pathway. SIP targeted metagenomics facilitated characterization of the primary metabolic

The influence of human physical activity and contaminated clothing type on particle resuspension

International Nuclear Information System (INIS)

McDonagh, A.; Byrne, M.A.

2014-01-01

A study was conducted to experimentally quantify the influence of three variables on the level of resuspension of hazardous aerosol particles from clothing. Variables investigated include physical activity level (two levels, low and high), surface type (four different clothing material types), and time i.e. the rate at which particles resuspend. A mixture of three monodisperse tracer-labelled powders, with median diameters of 3, 5, and 10 microns, was used to “contaminate” the samples, and the resuspended particles were analysed in real-time using an Aerodynamic Particle Sizer (APS), and also by Neutron Activation Analysis (NAA). The overall finding was that physical activity resulted in up to 67% of the contamination deposited on clothing being resuspended back into the air. A detailed examination of the influence of physical activity level on resuspension, from NAA, revealed that the average resuspended fraction (RF) of particles at low physical activity was 28 ± 8%, and at high physical activity was 30 ± 7%, while the APS data revealed a tenfold increase in the cumulative mass of airborne particles during high physical activity in comparison to that during low physical activity. The results also suggest that it is not the contaminated clothing's fibre type which influences particle resuspension, but the material's weave pattern (and hence the material's surface texture). Investigation of the time variation in resuspended particle concentrations indicated that the data were separable into two distinct regimes: the first (occurring within the first 1.5 min) having a high, positive rate of change of airborne particle concentration relative to the second regime. The second regime revealed a slower rate of change of particle concentration and remained relatively unchanged for the remainder of each resuspension event. -- Highlights: • Experimental investigation of the resuspension of hazardous particles from clothing. • Influence of human physical activity

Newly identified essential amino acid residues affecting ^8-sphingolipid desaturase activity revealed by site-directed mutagenesis

Science.gov (United States)

In order to identify amino acid residues crucial for the enzymatic activity of ^8-sphingolipid desaturases, a sequence comparison was performed among ^8-sphingolipid desaturases and ^6-fatty acid desaturase from various plants. In addition to the known conserved cytb5 (cytochrome b5) HPGG motif and...

Examining daily activity routines of older adults using workflow.

Science.gov (United States)

Chung, Jane; Ozkaynak, Mustafa; Demiris, George

2017-07-01

We evaluated the value of workflow analysis supported by a novel visualization technique to better understand the daily routines of older adults and highlight their patterns of daily activities and normal variability in physical functions. We used a self-reported activity diary to obtain data from six community-dwelling older adults for 14 consecutive days. Workflow for daily routine was analyzed using the EventFlow tool, which aggregates workflow information to highlight patterns and variabilities. A total of 1453 events were included in the data analysis. To demonstrate the patterns and variability of each individual's daily activities, participant activity workflows were visualized and compared. The workflow analysis revealed great variability in activity types, regularity, frequency, duration, and timing of performing certain activities across individuals. Also, when workflow approach was applied to spatial information of activities, the analysis revealed the ability to provide meaningful data on individuals' mobility in different levels of life spaces from home to community. Results suggest that using workflows to characterize the daily activities of older adults will be helpful for clinicians and researchers in understanding their daily routines and preparing education and prevention strategies tailored to each individual's activity level. This tool also has the potential to be integrated into consumer informatics technologies, such as patient portals or personal health records, so that consumers may be encouraged to become actively involved in monitoring and managing their health. Copyright © 2017 Elsevier Inc. All rights reserved.

High-speed image analysis reveals chaotic vibratory behaviors of pathological vocal folds

Energy Technology Data Exchange (ETDEWEB)

Zhang Yu, E-mail: yuzhang@xmu.edu.c [Key Laboratory of Underwater Acoustic Communication and Marine Information Technology of the Ministry of Education, Xiamen University, Xiamen Fujian 361005 (China); Shao Jun [Shanghai EENT Hospital of Fudan University, Shanghai (China); Krausert, Christopher R. [Department of Surgery, Division of Otolaryngology - Head and Neck Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI 53792-7375 (United States); Zhang Sai [Key Laboratory of Underwater Acoustic Communication and Marine Information Technology of the Ministry of Education, Xiamen University, Xiamen Fujian 361005 (China); Jiang, Jack J. [Shanghai EENT Hospital of Fudan University, Shanghai (China); Department of Surgery, Division of Otolaryngology - Head and Neck Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI 53792-7375 (United States)

2011-01-15

Research highlights: Low-dimensional human glottal area data. Evidence of chaos in human laryngeal activity from high-speed digital imaging. Traditional perturbation analysis should be cautiously applied to aperiodic high speed image signals. Nonlinear dynamic analysis may be helpful for understanding disordered behaviors in pathological laryngeal systems. - Abstract: Laryngeal pathology is usually associated with irregular dynamics of laryngeal activity. High-speed imaging facilitates direct observation and measurement of vocal fold vibrations. However, chaotic dynamic characteristics of aperiodic high-speed image data have not yet been investigated in previous studies. In this paper, we will apply nonlinear dynamic analysis and traditional perturbation methods to quantify high-speed image data from normal subjects and patients with various laryngeal pathologies including vocal fold nodules, polyps, bleeding, and polypoid degeneration. The results reveal the low-dimensional dynamic characteristics of human glottal area data. In comparison to periodic glottal area series from a normal subject, aperiodic glottal area series from pathological subjects show complex reconstructed phase space, fractal dimension, and positive Lyapunov exponents. The estimated positive Lyapunov exponents provide the direct evidence of chaos in pathological human vocal folds from high-speed digital imaging. Furthermore, significant differences between the normal and pathological groups are investigated for nonlinear dynamic and perturbation analyses. Jitter in the pathological group is significantly higher than in the normal group, but shimmer does not show such a difference. This finding suggests that the traditional perturbation analysis should be cautiously applied to high speed image signals. However, the correlation dimension and the maximal Lyapunov exponent reveal a statistically significant difference between normal and pathological groups. Nonlinear dynamic analysis is capable of

High-speed image analysis reveals chaotic vibratory behaviors of pathological vocal folds

International Nuclear Information System (INIS)