Mechano-adaptation of the stem cell nucleus.

Science.gov (United States)

Heo, Su-Jin; Cosgrove, Brian D; Dai, Eric N; Mauck, Robert L

2018-01-01

Exogenous mechanical forces are transmitted through the cell and to the nucleus, initiating mechanotransductive signaling cascades with profound effects on cellular function and stem cell fate. A growing body of evidence has shown that the force sensing and force-responsive elements of the nucleus adapt to these mechanotransductive events, tuning their response to future mechanical input. The mechanisms underlying this "mechano-adaptation" are only just beginning to be elucidated, and it remains poorly understood how these components act and adapt in tandem to drive stem cell differentiation. Here, we review the evidence on how the stem cell nucleus responds and adapts to physical forces, and provide a perspective on how this mechano-adaptation may function to drive and enforce stem cell differentiation.

K+ nucleus total cross sections

International Nuclear Information System (INIS)

Sawafta, R.

1990-01-01

The scattering of K + mesons from nuclei has attracted considerable interest in the last few years. The K + holds a very special position as the weakest of all strongly interaction probes. The average cross section is not larger than about 10 mb at lab momenta below 800 MeV/c, corresponding to a mean free path in the nucleus larger than 5 fm. Thus the K + is capable of probing the entire volume of the nucleus. Single scattering of the K + with a nucleon in the nucleus dominates the nuclear scattering, and only small and calculable higher order corrections are needed. The nucleon is a dynamical entity and its internal structure can, in principle, be altered by its surrounding nuclear environment. This work reports an experiment in which the K + is used to compare the nucleon in the nucleus with a free nucleon

Sexual differentiation of the brain: a model for drug-induced alterations of the reproductive system

International Nuclear Information System (INIS)

Gorski, R.A.

1986-01-01

The process of the sexual differentiation of the brain represents a valuable model system for the study of the chemical modification of the mammalian brain. Although there are numerous functional and structural sex differences in the adult brain, these are imposed on an essentially feminine or bipotential brain by testicular hormones during a critical phase of perinatal development in the rat. It is suggested that a relatively marked structural sex difference in the rat brain, the sexually dimorphic nucleus of the preoptic area (SDN-POA), is a morphological signature of the permanent or organizational action of estradiol derived from the aromatization of testicular testosterone. The SDN-POA of the male rat is severalfold larger in volume and is composed of more neurons than that of the female. The observation that the mitotic formation of the neurons of the SDN-POA is specifically prolonged has enabled us to identify the time course and pathway of neuronal migration into the nucleus. Study of the development of the SDN-POA suggests that estradiol in the male increases the number of neurons which survive a phase of neuronal death by exerting a neurite growth promoting action and/or a direct neuronotrophic action. Finally, although it is clear that gonadal hormones have dramatic permanent effects on the brain during perinatal development, even after puberty and in adulthood gonadal steroids can alter neuronal structure and, perhaps as a corollary to this, have permanent effects on reproductive function. Although the brain may be most sensitive to gonadal hormones or exogenous chemical factors during perinatal development, such as sensitivity does not appear limited to this period

Manifestation of jet quenching in differential distributions of the total transverse energy in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Savina, M.V.; Shmatov, S.V.; Slavin, N.V.; Zarubin, P.I.

1998-01-01

In the framework of the HIJING model, global characteristics of nucleus-nucleus collisions are studied for a Large Hadron Collider (LHC) energy scale. An interesting model prediction is the presence of a central bump over a pseudorapidity plateau of a total transverse energy distribution. The bump is induced by a jet quenching effect in a dense nuclear matter. It is shown that a wide acceptance calorimeter with a pseudorapidity coverage -5<η<5 allows one to obtain experimental confirmation of such an effect

Addiction and Reward-related Genes Show Altered Expression in the Postpartum Nucleus Accumbens

Directory of Open Access Journals (Sweden)

Changjiu eZhao

2014-11-01

Full Text Available Motherhood involves a switch in natural rewards, whereby offspring become highly rewarding. Nucleus accumbens (NAC is a key CNS region for natural rewards and addictions, but to date no study has evaluated on a large scale the events in NAC that underlie the maternal change in natural rewards. In this study we utilized microarray and bioinformatics approaches to evaluate postpartum NAC gene expression changes in mice. Modular Single-set Enrichment Test (MSET indicated that postpartum (relative to virgin NAC gene expression profile was significantly enriched for genes related to addiction and reward in 5 of 5 independently curated databases (e.g., Malacards, Phenopedia. Over 100 addiction/reward related genes were identified and these included: Per1, Per2, Arc, Homer2, Creb1, Grm3, Fosb, Gabrb3, Adra2a, Ntrk2, Cry1, Penk, Cartpt, Adcy1, Npy1r, Htr1a, Drd1a, Gria1, and Pdyn. ToppCluster analysis found maternal NAC expression profile to be significantly enriched for genes related to the drug action of nicotine, ketamine, and dronabinol. Pathway analysis indicated postpartum NAC as enriched for RNA processing, CNS development/differentiation, and transcriptional regulation. Weighted Gene Coexpression Network Analysis identified possible networks for transcription factors, including Nr1d1, Per2, Fosb, Egr1, and Nr4a1. The postpartum state involves increased risk for mental health disorders and MSET analysis indicated postpartum NAC to be enriched for genes related to depression, bipolar disorder, and schizophrenia. Mental health related genes included: Fabp7, Grm3, Penk, and Nr1d1. We confirmed via quantitative PCR Nr1d1, Per2, Grm3, Penk, Drd1a, and Pdyn. This study indicates for the first time that postpartum NAC involves large scale gene expression alterations linked to addiction and reward. Because the postpartum state also involves decreased response to drugs, the findings could provide insights into how to mitigate addictions.

Distinct roles of presynaptic dopamine receptors in the differential modulation of the intrinsic synapses of medium-spiny neurons in the nucleus accumbens

Directory of Open Access Journals (Sweden)

Schmauss Claudia

2007-01-01

Full Text Available Abstract Background In both schizophrenia and addiction, pathological changes in dopamine release appear to induce alterations in the circuitry of the nucleus accumbens that affect coordinated thought and motivation. Dopamine acts principally on medium-spiny GABA neurons, which comprise 95% of accumbens neurons and give rise to the majority of inhibitory synapses in the nucleus. To examine dopamine action at single medium-spiny neuron synapses, we imaged Ca2+ levels in their presynaptic varicosities in the acute brain slice using two-photon microscopy. Results Presynaptic Ca2+ rises were differentially modulated by dopamine. The D1/D5 selective agonist SKF81297 was exclusively facilitatory. The D2/D3 selective agonist quinpirole was predominantly inhibitory, but in some instances it was facilitatory. Studies using D2 and D3 receptor knockout mice revealed that quinpirole inhibition was either D2 or D3 receptor-mediated, while facilitation was mainly D3 receptor-mediated. Subsets of varicosities responded to both D1 and D2 agonists, showing that there was significant co-expression of these receptor families in single medium-spiny neurons. Neighboring presynaptic varicosities showed strikingly heterogeneous responses to DA agonists, suggesting that DA receptors may be differentially trafficked to individual varicosities on the same medium-spiny neuron axon. Conclusion Dopamine receptors are present on the presynaptic varicosities of medium-spiny neurons, where they potently control GABAergic synaptic transmission. While there is significant coexpression of D1 and D2 family dopamine receptors in individual neurons, at the subcellular level, these receptors appear to be heterogeneously distributed, potentially explaining the considerable controversy regarding dopamine action in the striatum, and in particular the degree of dopamine receptor segregation on these neurons. Assuming that post-receptor signaling is restricted to the microdomains of

Diabatic emission of neutrons: A probe for the energy dissipation mechanism in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Noerenberg, W.; Cassing, W.

1984-05-01

The precompound emission of neutrons in central nucleus-nucleus collisions is investigated within the framework of dissipative diabatic dynamics. For 92 Mo + 92 Mo at bombarding energies between 7.5 and 20 MeV/u the differential neutron multiplicities dMsub(n)/dEsub(n) are estimated from the decay of highly excited diabatic single-particle states. The energy spectra have an almost exponential high-energy tail with effective temperatures up to 10 MeV for 20 MeV/u bombarding energy. (orig.)

Particle correlations in proton-nucleus and nucleus-nucleus collisions

International Nuclear Information System (INIS)

Nagamiya, Sh.

1981-01-01

Particle correlations in proton-nucleus and nucleus-nucleus collisions at energies of 1-2 GeV/nucleon are investigated. The problems of measurement of the mean free path lambda of protons inside the nucleus and the interaction radius of nucleus-nucleus collisions is considered. The value of lambda has been determined in two-proton coincidence experiment in proton-nucleus interaction at 800 MeV. The observed value of lambda is slightly longer than the expected from free nucleon-nucleon collisions. Some preliminary results on proton emission beyond free nucleon-nucleon kinemaics are given

Ethanol Exposure History and Alcoholic Reward Differentially Alter Dopamine Release in the Nucleus Accumbens to a Reward-Predictive Cue.

Science.gov (United States)

Fiorenza, Amanda M; Shnitko, Tatiana A; Sullivan, Kaitlin M; Vemuru, Sudheer R; Gomez-A, Alexander; Esaki, Julie Y; Boettiger, Charlotte A; Da Cunha, Claudio; Robinson, Donita L

2018-06-01

Conditioned stimuli (CS) that predict reward delivery acquire the ability to induce phasic dopamine release in the nucleus accumbens (NAc). This dopamine release may facilitate conditioned approach behavior, which often manifests as approach to the site of reward delivery (called "goal-tracking") or to the CS itself (called "sign-tracking"). Previous research has linked sign-tracking in particular to impulsivity and drug self-administration, and addictive drugs may promote the expression of sign-tracking. Ethanol (EtOH) acutely promotes phasic release of dopamine in the accumbens, but it is unknown whether an alcoholic reward alters dopamine release to a CS. We hypothesized that Pavlovian conditioning with an alcoholic reward would increase dopamine release triggered by the CS and subsequent sign-tracking behavior. Moreover, we predicted that chronic intermittent EtOH (CIE) exposure would promote sign-tracking while acute administration of naltrexone (NTX) would reduce it. Rats received 14 doses of EtOH (3 to 5 g/kg, intragastric) or water followed by 6 days of Pavlovian conditioning training. Rewards were a chocolate solution with or without 10% (w/v) alcohol. We used fast-scan cyclic voltammetry to measure phasic dopamine release in the NAc core in response to the CS and the rewards. We also determined the effect of NTX (1 mg/kg, subcutaneous) on conditioned approach. Both CIE and alcoholic reward, individually but not together, associated with greater dopamine to the CS than control conditions. However, this increase in dopamine release was not linked to greater sign-tracking, as both CIE and alcoholic reward shifted conditioned approach from sign-tracking behavior to goal-tracking behavior. However, they both also increased sensitivity to NTX, which reduced goal-tracking behavior. While a history of EtOH exposure or alcoholic reward enhanced dopamine release to a CS, they did not promote sign-tracking under the current conditions. These findings are

THC alters alters morphology of neurons in medial prefrontal cortex, orbital prefrontal cortex, and nucleus accumbens and alters the ability of later experience to promote structural plasticity.

Science.gov (United States)

Kolb, Bryan; Li, Yilin; Robinson, Terry; Parker, Linda A

2018-03-01

Psychoactive drugs have the ability to alter the morphology of neuronal dendrites and spines and to influence later experience-dependent structural plasticity. If rats are given repeated injections of psychomotor stimulants (amphetamine, cocaine, nicotine) prior to being placed in complex environments, the drug experience interferes with the ability of the environment to increase dendritic arborization and spine density. Repeated exposure to Delta 9-Tetrahydrocannabinol (THC) changes the morphology of dendrites in medial prefrontal cortex (mPFC) and nucleus accumbens (NAcc). To determine if drugs other than psychomotor stimulants will also interfere with later experience-dependent structural plasticity we gave Long-Evans rats THC (0.5 mg/kg) or saline for 11 days before placing them in complex environments or standard laboratory caging for 90 days. Brains were subsequently processed for Golgi-Cox staining and analysis of dendritic morphology and spine density mPFC, orbital frontal cortex (OFC), and NAcc. THC altered both dendritic arborization and spine density in all three regions, and, like psychomotor stimulants, THC influenced the effect of later experience in complex environments to shape the structure of neurons in these three regions. We conclude that THC may therefore contribute to persistent behavioral and cognitive deficits associated with prolonged use of the drug. © 2017 Wiley Periodicals, Inc.

K sup + nucleus total cross sections

Energy Technology Data Exchange (ETDEWEB)

Sawafta, R.

1990-01-01

The scattering of K{sup +} mesons from nuclei has attracted considerable interest in the last few years. The K{sup +} holds a very special position as the weakest of all strongly interaction probes. The average cross section is not larger than about 10 mb at lab momenta below 800 MeV/c, corresponding to a mean free path in the nucleus larger than 5 fm. Thus the K{sup +} is capable of probing the entire volume of the nucleus. Single scattering of the K{sup +} with a nucleon in the nucleus dominates the nuclear scattering, and only small and calculable higher order corrections are needed. The nucleon is a dynamical entity and its internal structure can, in principle, be altered by its surrounding nuclear environment. This work reports an experiment in which the K{sup +} is used to compare the nucleon in the nucleus with a free nucleon.

Altered MENIN expression disrupts the MAFA differentiation pathway in insulinoma.

Science.gov (United States)

Hamze, Z; Vercherat, C; Bernigaud-Lacheretz, A; Bazzi, W; Bonnavion, R; Lu, J; Calender, A; Pouponnot, C; Bertolino, P; Roche, C; Stein, R; Scoazec, J Y; Zhang, C X; Cordier-Bussat, M

2013-12-01

The protein MENIN is the product of the multiple endocrine neoplasia type I (MEN1) gene. Altered MENIN expression is one of the few events that are clearly associated with foregut neuroendocrine tumours (NETs), classical oncogenes or tumour suppressors being not involved. One of the current challenges is to understand how alteration of MENIN expression contributes to the development of these tumours. We hypothesised that MENIN might regulate factors maintaining endocrine-differentiated functions. We chose the insulinoma model, a paradigmatic example of well-differentiated pancreatic NETs, to study whether MENIN interferes with the expression of v-MAF musculoaponeurotic fibrosarcoma oncogene homologue A (MAFA), a master glucose-dependent transcription factor in differentiated β-cells. Immunohistochemical analysis of a series of human insulinomas revealed a correlated decrease in both MENIN and MAFA. Decreased MAFA expression resulting from targeted Men1 ablation was also consistently observed in mouse insulinomas. In vitro analyses using insulinoma cell lines showed that MENIN regulated MAFA protein and mRNA levels, and bound to Mafa promoter sequences. MENIN knockdown concomitantly decreased mRNA expression of both Mafa and β-cell differentiation markers (Ins1/2, Gck, Slc2a2 and Pdx1) and, in parallel, increased the proliferation rate of tumours as measured by bromodeoxyuridine incorporation. Interestingly, MAFA knockdown alone also increased proliferation rate but did not affect the expression of candidate proliferation genes regulated by MENIN. Finally, MENIN variants with missense mutations detected in patients with MEN1 lost the WT MENIN properties to regulate MAFA. Together, our findings unveil a previously unsuspected MENIN/MAFA connection regarding control of the β-cell differentiation/proliferation balance, which could contribute to tumorigenesis.

Nucleus-nucleus potential with repulsive core and elastic scattering. Part 1. Nucleus-nucleus interaction potential

International Nuclear Information System (INIS)

Davidovs'ka, O.Yi.; Denisov, V.Yu.; Nesterov, V.O.

2010-01-01

Various approaches for nucleus-nucleus interaction potential evaluation are discussed in details. It is shown that the antisymmetrization of nucleons belonging to different nuclei and the Pauli principle give the essential contribution into the nucleus-nucleus potential at distances, when nuclei are strongly overlapping, and lead to appearance of the repulsive core of nucleus nucleus interaction at small distances between nuclei.

Statistical point of view on nucleus excited states and fluctuations of differential polarization of particles emitted during nuclear reactions

International Nuclear Information System (INIS)

Dumazet, Gerard

1965-01-01

As previous works notably performed by Ericson outlined the fact that the compound nucleus model resulted in variations of efficient cross sections about average values and that these variations were not negligible at all as it had been previously admitted, this research thesis aims at establishing theoretical predictions and at showing that Ericson's predictions can be extended to polarization. After having qualitatively and quantitatively recalled the underlying concepts used in the compound nucleus and direct interaction models, the author shows the relevance of a statistical point of view on nuclei which must not be confused with the statistical model itself. Then, after a recall of results obtained by Ericson, the author reports the study of the fluctuations of differential polarization, addresses the experimental aspect of fluctuations, and shows which are the main factors for this kind of study [fr

Momentum loss in proton-nucleus and nucleus-nucleus collisions

International Nuclear Information System (INIS)

Khan, F.; Townsend, L.W.

1993-12-01

An optical model description, based on multiple scattering theory, of longitudinal momentum loss in proton-nucleus and nucleus-nucleus collisions is presented. The crucial role of the imaginary component of the nucleon-nucleon transition matrix in accounting for longitudinal momentum transfer is demonstrated. Results obtained with this model are compared with Intranuclear Cascade (INC) calculations, as well as with predictions from Vlasov-Uehling-Uhlenbeck (VUU) and quantum molecular dynamics (QMD) simulations. Comparisons are also made with experimental data where available. These indicate that the present model is adequate to account for longitudinal momentum transfer in both proton-nucleus and nucleus-nucleus collisions over a wide range of energies

Cocaine alters Homer1 natural antisense transcript in the nucleus accumbens.

Science.gov (United States)

Sartor, Gregory C; Powell, Samuel K; Velmeshev, Dmitry; Lin, David Y; Magistri, Marco; Wiedner, Hannah J; Malvezzi, Andrea M; Andrade, Nadja S; Faghihi, Mohammad A; Wahlestedt, Claes

2017-12-01

Natural antisense transcripts (NATs) are an abundant class of long noncoding RNAs that have recently been shown to be key regulators of chromatin dynamics and gene expression in nervous system development and neurological disorders. However, it is currently unclear if NAT-based mechanisms also play a role in drug-induced neuroadaptations. Aberrant regulation of gene expression is one critical factor underlying the long-lasting behavioral abnormalities that characterize substance use disorder, and it is possible that some drug-induced transcriptional responses are mediated, in part, by perturbations in NAT activity. To test this hypothesis, we used an automated algorithm that mines the NCBI AceView transcriptomics database to identify NAT overlapping genes linked to addiction. We found that 22% of the genes examined contain NATs and that expression of Homer1 natural antisense transcript (Homer1-AS) was altered in the nucleus accumbens (NAc) of mice 2h and 10days following repeated cocaine administration. In in vitro studies, depletion of Homer1-AS lead to an increase in the corresponding sense gene expression, indicating a potential regulatory mechanisms of Homer1 expression by its corresponding antisense transcript. Future in vivo studies are needed to definitely determine a role for Homer1-AS in cocaine-induced behavioral and molecular adaptations. Copyright © 2017 Elsevier Inc. All rights reserved.

Mechanisms of High Energy Hadron-Nucleus and Nucleus-Nucleus Collision Processes

International Nuclear Information System (INIS)

Strugalski, Z.

1994-01-01

Mechanisms of high energy hadron-nucleus and nucleus-nucleus collision processes are depicted qualitatively, as prompted experimentally. In hadron-nucleus collisions the interaction of the incident hadron in intranuclear matter is localized in small cylindrical volume, with the radius as large as the strong interaction range is, centered on the hadron course in the nucleus. The nucleon emission is induced by the hadron in its passing through the nucleus; particles are produced via intermediate objects produced in 2 → 2 endoergic reactions of the hadron and its successors with downstream nucleons. In nucleus-nucleus collisions, the outcome of the reaction appears as the composition of statistically independent hadron-nucleus collision outcomes at various impact parameters. Observable effects supporting such mechanisms are discussed. 51 refs

Antiproton production in nucleon-nucleus and nucleus-nucleus collisions at the CERN-SPS

International Nuclear Information System (INIS)

Kadija, K.; Schmitz, N.; Seyboth, P.

1996-01-01

A model for antiproton production in nucleon-nucleus and nucleus-nucleus collisions at 200 GeV per nucleon, based on the wounded nucleon model is developed. The predictions are compared to published nucleon-nucleus and sulphur-nucleus data. The results suggest the presence of similar antiproton production processes in nucleon-nucleus and nucleus-nucleus collisions near midrapidity. (orig.)

Nucleus-nucleus total reaction cross sections

International Nuclear Information System (INIS)

DeVries, R.M.; Peng, J.C.

1980-01-01

We compare sigma/sub R/(E) for nucleus-nucleus systems (obtained from existing direct measurements and derived from elastic scattering data) with nucleon-nucleon and nucleon-nucleus data. The energy dependence of sigma/sub R/(E) for nucleus-nucleus systems is found to be quite rapid; there appears to be no evidence for an energy independent, geometric sigma/sub R/. Simple parameter free microscopic calculations are able to quantitatively reproduce the data and thus, emphasize the dominance of nucleon-nucleon interactions in medium energy nucleus-nucleus collisions

Nucleus-Nucleus Collision as Superposition of Nucleon-Nucleus Collisions

International Nuclear Information System (INIS)

Orlova, G.I.; Adamovich, M.I.; Aggarwal, M.M.; Alexandrov, Y.A.; Andreeva, N.P.; Badyal, S.K.; Basova, E.S.; Bhalla, K.B.; Bhasin, A.; Bhatia, V.S.; Bradnova, V.; Bubnov, V.I.; Cai, X.; Chasnikov, I.Y.; Chen, G.M.; Chernova, L.P.; Chernyavsky, M.M.; Dhamija, S.; Chenawi, K.El; Felea, D.; Feng, S.Q.; Gaitinov, A.S.; Ganssauge, E.R.; Garpman, S.; Gerassimov, S.G.; Gheata, A.; Gheata, M.; Grote, J.; Gulamov, K.G.; Gupta, S.K.; Gupta, V.K.; Henjes, U.; Jakobsson, B.; Kanygina, E.K.; Karabova, M.; Kharlamov, S.P.; Kovalenko, A.D.; Krasnov, S.A.; Kumar, V.; Larionova, V.G.; Li, Y.X.; Liu, L.S.; Lokanathan, S.; Lord, J.J.; Lukicheva, N.S.; Lu, Y.; Luo, S.B.; Mangotra, L.K.; Manhas, I.; Mittra, I.S.; Musaeva, A.K.; Nasyrov, S.Z.; Navotny, V.S.; Nystrand, J.; Otterlund, I.; Peresadko, N.G.; Qian, W.Y.; Qin, Y.M.; Raniwala, R.; Rao, N.K.; Roeper, M.; Rusakova, V.V.; Saidkhanov, N.; Salmanova, N.A.; Seitimbetov, A.M.; Sethi, R.; Singh, B.; Skelding, D.; Soderstrem, K.; Stenlund, E.; Svechnikova, L.N.; Svensson, T.; Tawfik, A.M.; Tothova, M.; Tretyakova, M.I.; Trofimova, T.P.; Tuleeva, U.I.; Vashisht, Vani; Vokal, S.; Vrlakova, J.; Wang, H.Q.; Wang, X.R.; Weng, Z.Q.; Wilkes, R.J.; Yang, C.B.; Yin, Z.B.; Yu, L.Z.; Zhang, D.H.; Zheng, P.Y.; Zhokhova, S.I.; Zhou, D.C.

1999-01-01

Angular distributions of charged particles produced in 16 O and 32 S collisions with nuclear track emulsion were studied at momenta 4.5 and 200 A GeV/c. Comparison with the angular distributions of charged particles produced in proton-nucleus collisions at the same momentum allows to draw the conclusion, that the angular distributions in nucleus-nucleus collisions can be seen as superposition of the angular distributions in nucleon-nucleus collisions taken at the same impact parameter b NA , that is mean impact parameter between the participating projectile nucleons and the center of the target nucleus

Nucleus-Nucleus Collision as Superposition of Nucleon-Nucleus Collisions

Energy Technology Data Exchange (ETDEWEB)

Orlova, G I; Adamovich, M I; Aggarwal, M M; Alexandrov, Y A; Andreeva, N P; Badyal, S K; Basova, E S; Bhalla, K B; Bhasin, A; Bhatia, V S; Bradnova, V; Bubnov, V I; Cai, X; Chasnikov, I Y; Chen, G M; Chernova, L P; Chernyavsky, M M; Dhamija, S; Chenawi, K El; Felea, D; Feng, S Q; Gaitinov, A S; Ganssauge, E R; Garpman, S; Gerassimov, S G; Gheata, A; Gheata, M; Grote, J; Gulamov, K G; Gupta, S K; Gupta, V K; Henjes, U; Jakobsson, B; Kanygina, E K; Karabova, M; Kharlamov, S P; Kovalenko, A D; Krasnov, S A; Kumar, V; Larionova, V G; Li, Y X; Liu, L S; Lokanathan, S; Lord, J J; Lukicheva, N S; Lu, Y; Luo, S B; Mangotra, L K; Manhas, I; Mittra, I S; Musaeva, A K; Nasyrov, S Z; Navotny, V S; Nystrand, J; Otterlund, I; Peresadko, N G; Qian, W Y; Qin, Y M; Raniwala, R; Rao, N K; Roeper, M; Rusakova, V V; Saidkhanov, N; Salmanova, N A; Seitimbetov, A M; Sethi, R; Singh, B; Skelding, D; Soderstrem, K; Stenlund, E; Svechnikova, L N; Svensson, T; Tawfik, A M; Tothova, M; Tretyakova, M I; Trofimova, T P; Tuleeva, U I; Vashisht, Vani; Vokal, S; Vrlakova, J; Wang, H Q; Wang, X R; Weng, Z Q; Wilkes, R J; Yang, C B; Yin, Z B; Yu, L Z; Zhang, D H; Zheng, P Y; Zhokhova, S I; Zhou, D C

1999-03-01

Angular distributions of charged particles produced in {sup 16}O and {sup 32}S collisions with nuclear track emulsion were studied at momenta 4.5 and 200 A GeV/c. Comparison with the angular distributions of charged particles produced in proton-nucleus collisions at the same momentum allows to draw the conclusion, that the angular distributions in nucleus-nucleus collisions can be seen as superposition of the angular distributions in nucleon-nucleus collisions taken at the same impact parameter b{sub NA}, that is mean impact parameter between the participating projectile nucleons and the center of the target nucleus.

Nucleus-nucleus collision as superposition of nucleon-nucleus collisions

International Nuclear Information System (INIS)

Orlova, G.I.; Adamovich, M.I.; Aggarwal, M.M.

1999-01-01

Angular distributions of charged particles produced in 16 O and 32 S collisions with nuclear track emulsion were studied at momenta 4.5 and 200 A GeV/c. Comparison with the angular distributions of charged particles produced in proton-nucleus collisions at the same momentum allows to draw the conclusion, that the angular distributions in nucleus-nucleus collisions can be seen as superposition of the angular distributions in nucleon-nucleus collisions taken at the same impact parameter b NA , that is mean impact parameter between the participating projectile nucleons and the center of the target nucleus. (orig.)

Transport theory applied to hadron and light fragment production in high energy nucleus-nucleus collisions

International Nuclear Information System (INIS)

Schuermann, B.; Malfliet, R.; Mies, S.; Zwermann, W.

1984-01-01

Foundations of the transport theory for studying K + , K - , π - and light fragment production in nucleus-nucleus interactions at high energies are given. Inclusive production of protons, K + and π - in the Ne+NaF reaction at 400 MeV and 21 GeV/nucleon is consdered, their differential cross sections are caculated. Differential cross sections of K - and π - production in Si+Si → K + +X and Ne+NaF → π - +X reactions at the energy of 2.1 GeV/nucleon, their energy dependence are estimated. Comparison of the calculated and experimental data is graphically presented. The model of the transport theory is shown to successfully reproduce inclusive spectra of different particles (p, d, π, K + , K - ) in a wide energy range of incident particles (from 400 MeV to 2 GeV/nucleon). This approach can be generalized for lower energies by generating a mean nuclear potentiasl field

Calculations of nucleus-nucleus microscopic optical potentials at intermediate energies

International Nuclear Information System (INIS)

Hanna, K.M.; Kuhtina, I.N.; Lukyanov, K.V.; Lukyanov, V.K.; Zemlyanaya, E.V.; Slowinski, B.

2006-01-01

Three types of microscopic nucleus-nucleus optical potentials are constructed using three patterns for their real and imaginary parts. Two of these patterns are the real V H and imaginary W H parts of the potential which reproduces the high-energy amplitude of scattering in the microscopic Glauber-Sitenko theory. Another template VDF is calculated within the standard double-folding model with the exchange term included. For either of the three tested potentials, the contribution of real and imaginary patterns is adjusted by introducing two fitted factors. Correspondingly, using numerical code ECIS, the elastic differential cross-sections were fitted to the experimental data on scattering of the 16,17 O heavy-ions at about hundred Mev/nucleon on various target-nuclei. The relativization effect is also included. The tables of the obtained factors which renormalize the strengths of the real and (or) imaginary parts of the calculated microscopic potentials are given

Some experimental results of the investigation of hadron-nucleus and nucleus-nucleus interactions

International Nuclear Information System (INIS)

Azimov, S.A.; Gulamov, K.G.; Chernov, G.M.

1978-01-01

Recent experimental data on the hadron-nucleus and nucleus-nucleus inelastic interactions are analyzed. A particular attention is paid to the description of the leading hadron spectra and of the spectra of nucleon recoils in hadron-nucleus interactions. Some of the results of the experimental studies of correlations between secondary particles are discussed. This discussion demonstrates that an analysis of the multiparticle phenomena is very promising regarding the discrimination between the different models for the hadron-nucleus and nucleus-nucleus interactions. It is pointed out that the actual mechanism of the hadron-nucleus and nucleus-nucleus interactions is a rather complex one and can be described comprehensively by none of the existing models

Elastic scattering of protons on 8Li nucleus in inverse kinematics

International Nuclear Information System (INIS)

Zhusupov, M.A.; Ibraeva, E.T.; Sanfirova, A.B.; Imambekov, O.

2002-01-01

In the present paper the proton elastic scattering on 8 Li in inverse kinematics is studies. The inverse kinematics means that a beam of radioactive nuclei is scattered on a stable hydrogen target. Proton as a target has an advantage during the interaction since it is stable and mechanism of proton-nucleus scattering is quite simple. 8 Li nucleus is considered in the three-body αtn-model with realistic potential of inter-cluster interactions. The wave function of this nucleus is calculated in the work where it was shown that such model well describes the main spectroscopic characteristics of the nucleus, root-mean square radius, binding energy, location of low laying energy levels, magnetic momentum and also total cross section and 7 Li(n, γ) 8 Li reaction rate at a wide energy region. Within Glauber-Sitenko multiply scattering theory, the differential cross section of elastic p 8 Li-scattering has been calculated. The first and the second multiplicities of scattering on nucleons and clusters of the nucleus were taken into account in Ω multiply scattering operator. There were considered several cases when as the initial parameters both amplitudes of nucleon-nucleon and nucleon-cluster scattering were taken. Sensitivity of the differential cross section both to the different wave functions of the target-nucleus and to the parameters of the elementary amplitudes and sensitivity to the scattering multiplicities at several beam energies has been investigated. Comparison with differential cross sections of elastic p 6 Li- and p 7 Li scattering has been carried out

TCDD alters medial epithelial cell differentiation during palatogenesis

International Nuclear Information System (INIS)

Abbott, B.D.; Birnbaum, L.S.

1989-01-01

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a widely distributed, persistent environmental contaminant that is teratogenic in mice, where it induces hydronephrosis and cleft palate. The incidence of clefting has been shown to be dose dependent after exposure on either gestation Day (GD) 10 or 12, although the embryo is more susceptible on GD 12. TCDD-exposed palatal shelves meet but do not fuse, and programmed cell death of the medial epithelial cells is inhibited. The mechanism of action through which TCDD alters the program of medial cell development has not been examined in earlier studies, and it is not known whether the mechanism is the same regardless of the dose or developmental stage of exposure. In this study, C57BL/6N mice, a strain sensitive to TCDD, were dosed orally on GD 10 or 12 with 0, 6, 12, 24, or 30 micrograms/kg body wt, in 10 ml corn oil/kg. Embryonic palatal shelves were examined on GD 14, 15, or 16. The degree of palatal closure, epithelial surface morphology, and cellular ultrastructure, the incorporation of [3H]TdR, the expression of EGF receptors, and the binding of 125I-EGF were assessed. After exposure on GD 10 or 12, TCDD altered the differentiation pathway of the medial epithelial cells. The palatal shelves were of normal size and overall morphology, but fusion of the medial epithelia of the opposing shelves did not occur. TCDD prevented programmed cell death of the medial peridermal cells. The expression of EGF receptors by medial cells continued through Day 16 and the receptors were able to bind ligand. The medial cells differentiated into a stratified, squamous, keratinizing epithelium. The shift in phenotype to an oral-like epithelium occurred after exposure on either GD 10 or 12. At the lower dose (6 micrograms/kg), fewer cleft palates were produced, but those shelves which did respond had a fully expressed shift in differentiation

Nucleus and nucleus-cytoskeleton connections in 3D cell migration

Energy Technology Data Exchange (ETDEWEB)

Liu, Lingling, E-mail: liulingling2012@163.com; Luo, Qing, E-mail: qing.luo@cqu.edu.cn; Sun, Jinghui, E-mail: sunjhemail@163.com; Song, Guanbin, E-mail: song@cqu.edu.cn

2016-10-15

Cell migration plays an important role in many physiological and pathological settings, ranging from embryonic development to cancer metastasis. Currently, accumulating data suggest that cells migrating in three-dimensional (3D) environments show well-defined differences compared to their well-established two-dimensional (2D) counterparts. During 3D migration, the cell body and nucleus must deform to allow cellular passage through the available spaces, and the deformability of the relatively rigid nucleus may constitute a limiting step. Here, we highlight the key evidence regarding the role of the nuclear mechanics in 3D migration, including the molecular components that govern the stiffness of the nucleus and review how the nuclear dynamics are connected to and controlled by cytoskeleton-based migration machinery. Intriguingly, nuclear movement must be coordinated with the cytoskeletal dynamics at the leading and trailing edges, which in turn impact the cytoplasmic dynamics that affect the migration efficiency. Thus, we suggest that alterations in the nuclear structure may facilitate cellular reorganizations that are necessary for efficient migration. - Graphical abstract: Schematic representations of a cell migrating on a 2D substrate and a cell migrating in a 3D extracellular matrix environment. (A) Nucleus-cytoskeleton connections are essential to 3D migration. Mechanical signals are transduced by integrins at the cell surface and channeled to cytoskeletal proteins, which generates prestress. The nucleus-cytoskeleton connections can either act as a stable skeleton to anchor the nuclei or provide active force to move the nuclei. The LINC complex is responsible for the nucleo-cytoskeletal coupling. Nesprins connect the cytoskeletal proteins to the inner nuclear membrane proteins SUN1 and SUN2. The SUN proteins connect to the lamins that form the lamina, which attaches to the chromatin. This physical connectivity transmits the mechanical signals from receptors at

Nucleus and nucleus-cytoskeleton connections in 3D cell migration

International Nuclear Information System (INIS)

Liu, Lingling; Luo, Qing; Sun, Jinghui; Song, Guanbin

2016-01-01

Cell migration plays an important role in many physiological and pathological settings, ranging from embryonic development to cancer metastasis. Currently, accumulating data suggest that cells migrating in three-dimensional (3D) environments show well-defined differences compared to their well-established two-dimensional (2D) counterparts. During 3D migration, the cell body and nucleus must deform to allow cellular passage through the available spaces, and the deformability of the relatively rigid nucleus may constitute a limiting step. Here, we highlight the key evidence regarding the role of the nuclear mechanics in 3D migration, including the molecular components that govern the stiffness of the nucleus and review how the nuclear dynamics are connected to and controlled by cytoskeleton-based migration machinery. Intriguingly, nuclear movement must be coordinated with the cytoskeletal dynamics at the leading and trailing edges, which in turn impact the cytoplasmic dynamics that affect the migration efficiency. Thus, we suggest that alterations in the nuclear structure may facilitate cellular reorganizations that are necessary for efficient migration. - Graphical abstract: Schematic representations of a cell migrating on a 2D substrate and a cell migrating in a 3D extracellular matrix environment. (A) Nucleus-cytoskeleton connections are essential to 3D migration. Mechanical signals are transduced by integrins at the cell surface and channeled to cytoskeletal proteins, which generates prestress. The nucleus-cytoskeleton connections can either act as a stable skeleton to anchor the nuclei or provide active force to move the nuclei. The LINC complex is responsible for the nucleo-cytoskeletal coupling. Nesprins connect the cytoskeletal proteins to the inner nuclear membrane proteins SUN1 and SUN2. The SUN proteins connect to the lamins that form the lamina, which attaches to the chromatin. This physical connectivity transmits the mechanical signals from receptors at

Differential response of nucleus pulposus intervertebral disc cells to high salt, sorbitol, and urea.

Science.gov (United States)

Mavrogonatou, Eleni; Kletsas, Dimitris

2012-03-01

Nucleus pulposus intervertebral disc cells are routinely confronted with high osmolality in their microenvironment and respond to this stress in vitro by regulating cell cycle progression and by activating a DNA repair machinery in order to counteract its genotoxic effect. In the present study, we attempted to identify the origin of this osmo-regulatory response, by using an ionic NaCl/KCl solution, the compatible osmolyte sorbitol, and the readily permeant urea. High salt and sorbitol were found to activate similar molecular pathways, including the p38 MAPK and the p53-p21(WAF1)-pRb axis, that were not stimulated by high urea. On the other hand, only high urea led to the phosphorylation of ERKs and JNKs. Furthermore, salt- and sorbitol-treated cells were able to phosphorylate histone H2A.X on Ser139, in contrast to cells exposed to urea, indicating a common mechanism for DNA repair, which was achieved by a p53-dependent activation of the G1 checkpoint by both solutes. DNA repair, as directly measured by a host cell reactivation assay, occurred under conditions of hyperosmolar salt and sorbitol, although to a lesser extent in sorbitol-treated cells than in cells exposed to high salinity. Taken as a whole, our findings suggest that the hyperosmolality-provoked DNA damage and the responses of nucleus pulposus cells induced by this genotoxic stress most probably originate from cell volume alterations mediated by hypertonicity and not from increased intracellular ionic concentration. Copyright © 2011 Wiley Periodicals, Inc.

High energy nucleus-nucleus scattering and matter radius of unstable nucleus

International Nuclear Information System (INIS)

Sato, H.; Okuhara, Y.

1985-07-01

The interaction cross sections of high energy nucleus-nucleus scattering have been studied with the Glauber Model and Hartree-Fock like variational calculation for the nuclear structure. It is found that the experimental interaction cross sections of the light unstable nucleus-stable nucleus scatterings measured by INS-LBL collaboration are well reproduceable. (author)

High energy nucleus-nucleus collisions

International Nuclear Information System (INIS)

Bhalla, K.B.

1980-01-01

An attempt is made to explain nucleus-nucleus collisions based on nuclear emulsion experiments. Peripheral and central collisions are described in detail. Assuming the fireball model, the concepts of geometry, kinematics and thermodynamics in this model are discussed. Projectile and target fragmentations are studied. The advantages of using nuclear emulsions as detectors, are mentioned. Proton-nucleus collisions and nucleus-nucleus collisions are compared. Interactions, of projectiles such as Ca, B and C on targets such as Pb, Ag, Br etc. at very high energies (approximately 300 to 1700 Gev) are listed. A comparison of the near multiplicities in these interactions is given. A generalized explanation is given on the processes involved in these interactions. (A.K.)

Interacting gluon model for hadron-nucleus and nucleus-nucleus collisions in the central rapidity region

International Nuclear Information System (INIS)

Fowler, G.N.; Navarra, F.S.; Plumer, M.; Lawrence Berkeley Laboratory, Nuclear Science Division, Berkeley, California 94720); Vourdas, A.; Weiner, R.M.

1989-01-01

The interacting gluon model developed to describe the inelasticity distribution in hadron-nucleon collisions has been generalized and applied to hadron-nucleus and nucleus-nucleus interactions. Leading particle spectra and energy distributions in hadron-nucleus and nucleus-nucleus collisions are calculated

What can we learn from high-energy hadron-nucleus interactions

International Nuclear Information System (INIS)

Tow, D.M.

1979-12-01

High-energy hadron-nucleus (hA) collisions provide the exciting possibility of giving information about the spacetime development of hadron-hadron interactions and therefore differentiating various multiparticle production models. Some of the major developments in this field during the past decade, both experimentally and theoretically are reviewed. Several general features of the data are pointed out, and several classes of models are discussed. A recently proposed simple spacetime model for high-energy hA collisions is elaborated. Comments are made on the extension to nucleus-nucleus interactions and the future outlook

Nucleus accumbens opioid, GABaergic, and dopaminergic modulation of palatable food motivation: contrasting effects revealed by a progressive ratio study in the rat.

Science.gov (United States)

Zhang, Min; Balmadrid, Christian; Kelley, Ann E

2003-04-01

The current studies were designed to evaluate whether incentive motivation for palatable food is altered after manipulations of opioid, GABAergic, and dopaminergic transmission within the nucleus accumbens. A progressive ratio schedule was used to measure lever-pressing for sugar pellets after microinfusion of drugs into the nucleus accumbens in non-food-deprived rats. The mu opioid agonist D-Ala2, NMe-Phe4, Glyo15-enkephalin and the indirect dopamine agonist amphetamine induced a marked increase in break point and correct lever-presses; the GABA(A) agonist muscimol did not affect breakpoint or lever-presses. The data suggest that opioid, dopaminergic, and GABAergic systems within the accumbens differentially modulate food-seeking behavior through mechanisms related to hedonic evaluation of food, incentive salience, and control of motor feeding circuits, respectively.

Alterations in Factors Involved in Differentiation and Barrier Function in the Epithelium in Oral and Genital Lichen Planus.

Science.gov (United States)

Danielsson, Karin; Ebrahimi, Majid; Nylander, Elisabet; Wahlin, Ylva Britt; Nylander, Karin

2017-02-08

Lichen planus is a chronic recurrent inflammatory disease affecting both skin and mucosa, mainly in oral and/or genital regions. Keratinocytes go through a well-regulated process of proliferation and differentiation, alterations in which may result in defects in the protective epithelial barrier. Long-term barrier impairment might lead to chronic inflammation. In order to broaden our understanding of the differentiation process in mucosal lichen planus, we mapped the expression of 4 factors known to be involved in differentiation. Biopsies were collected from oral and genital lichen planus lesions and normal controls. Altered expression of all 4 factors in epithelium from lichen planus lesions was found, clearly indicating disturbed epithelial differentiation in lichen planus lesions.

The calculation of nucleus-nucleus interaction cross sections at high energy in the Glauber approach

International Nuclear Information System (INIS)

Gal'perin, A.G.; Uzhinskij, V.V.

1994-01-01

Total, inelastic and elastic cross sections of nucleus-nucleus (AA)-interactions at high energy (HE) are calculated on the base of Glauber approach. The calculation scheme is realized as a set of routines. The statistical average method is used in calculations. Program runs in an interactive regime. User is prompted about charge and mass numbers of nuclei and NN-interaction characters at the energy he is interested in: total cross section, the slope parameter of differential cross section of elastic scattering and ratio of real part to imaginary part of elastic scattering amplitude at zero momentum transfer. These data can be extracted from proper compilations. Results of calculations are displayed and are written on user defined output file. The program runs on PC. 21 refs., 1 tab

Diffractive ''semioptical'' model for nucleus-nucleus collisions

International Nuclear Information System (INIS)

Barashenkov, V.S.; Musulmanbekov, Zh.Zh.

1979-01-01

Diffraction Glauber theory for nucleus-nucleus collisions is considered in approximation when the initial nucleus interacts as a whole with nucleons of the target nucleus. Such an approach, being intermediate between precise Glauber theory and its optical limit, essentially simplifies numerical calculations and gives a good agreement with experiments as well. (author)

Transient alterations in neurotransmitter activity in the caudate nucleus of rat brain after a high dose of ionizing radiation

International Nuclear Information System (INIS)

Hunt, W.A.; Dalton, T.K.; Darden, J.H.

1979-01-01

A single 10,000-rad dose of high-energy electrons induced an increase in dopaminergic and cholinergic activity in the caudate nucleus of the rat brain as assessed by K + -stimulated dopamine release in vitro and high-affinity choline uptake. These alterations occur during early transient incapacitation (ETI) and dissipate as the animal recovers behaviorally, in about 30 min after irradiation. Although the responses observed resemble those that result from blockade of dopamine receptors, no radiation-induced changes were found in dopamine-sensitive adenylate cyclase activity and [ 3 H]haloperidol binding, two indices of dopaminergic receptor function. The data suggest that changes in dopaminergic and cholinergic activity are associated with the development of ETI and may play a role in the behavioral decrement observed under this condition

Protein expression in the nucleus accumbens of rats exposed to developmental vitamin D deficiency.

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John McGrath

Full Text Available INTRODUCTION: Developmental vitamin D (DVD deficiency is a candidate risk factor for schizophrenia. Animal models have confirmed that DVD deficiency is associated with a range of altered genomic, proteomic, structural and behavioural outcomes in the rat. Because the nucleus accumbens has been implicated in neuropsychiatric disorders, in the current study we examined protein expression in this region in adult rats exposed to DVD deficiency METHODS: Female Sprague Dawley rats were maintained on a vitamin D deficient diet for 6 weeks, mated and allowed to give birth, after which a diet containing vitamin D was reintroduced. Male adult offspring (n = 8 were compared to control male (n = 8. 2-D gel electrophoresis-based proteomics and mass spectroscopy were used to investigate differential protein expression. RESULTS: There were 35 spots, mapped to 33 unique proteins, which were significantly different between the two groups. Of these, 22 were down-regulated and 13 up-regulated. The fold changes were uniformly small, with the largest FC being -1.67. Within the significantly different spots, three calcium binding proteins (calbindin1, calbindin2 and hippocalcin were altered. Other proteins associated with DVD deficiency related to mitochondrial function, and the dynamin-like proteins. CONCLUSIONS: Developmental vitamin D deficiency was associated with subtle changes in protein expression in the nucleus accumbens. Disruptions in pathways related to calcium-binding proteins and mitochondrial function may underlie some of the behavioural features associated with animal models of developmental vitamin D deficiency.

Differential Gene Expression Profile in the Rat Caudal Vestibular Nucleus is Associated with Individual Differences in Motion Sickness Susceptibility.

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Jun-Qin Wang

Full Text Available To identify differentially expressed genes associated with motion sickness (MS susceptibility in the rat caudal vestibular nucleus.We identified MS susceptible (MSS and insusceptible (inMSS rats by quantifying rotation-induced MS symptoms: defecation and spontaneous locomotion activity. Microarray analysis was used to screen differentially expressed genes in the caudal vestibular nucleus (CVN after rotation. Plasma stress hormones were identified by radioimmunoassay. Candidate genes were selected by bioinformatics analysis and the microarray results were verified by real-time quantitative-PCR (RT-qPCR methods. By using Elvax implantation, receptor antagonists or recombinant adenovirus targeting the candidate genes were applied to the CVN to evaluate their contribution to MS susceptibility variability. Validity of gene expression manipulation was verified by RT-qPCR and western blot analysis.A total of 304 transcripts were differentially expressed in the MSS group compared with the inMSS group. RT-qPCR analysis verified the expression pattern of candidate genes, including nicotinic cholinergic receptor (nAchR α3 subunit, 5-hydroxytryptamine receptor 4 (5-HT4R, tachykinin neurokinin-1 (NK1R, γ-aminobutyric acid A receptor (GABAAR α6 subunit, olfactory receptor 81 (Olr81 and homology 2 domain-containing transforming protein 1 (Shc1. In MSS animals, the nAchR antagonist mecamylamine significantly alleviated rotation-induced MS symptoms and the plasma β-endorphin response. The NK1R antagonist CP99994 and Olr81 knock-down were effective for the defecation response, while the 5-HT4R antagonist RS39604 and Shc1 over-expression showed no therapeutic effect. In inMSS animals, rotation-induced changes in spontaneous locomotion activity and the plasma β-endorphin level occurred in the presence of the GABAAR antagonist gabazine.Our findings suggested that the variability of the CVN gene expression profile after motion stimulation might be a putative

Photoproduction of lepton pairs in proton-nucleus and nucleus-nucleus collisions at RHIC and LHC energies

Energy Technology Data Exchange (ETDEWEB)

Moreira, B. D.; Goncalves, V. P.; De Santana Amaral, J. T. [Universidade Federal de Pelotas, Instituto de Fisica e Matematica (Brazil)

2013-03-25

In this contribution we study coherent interactions as a probe of the nonlinear effects in the Quantum Electrodynamics (QED). In particular, we study the multiphoton effects in the production of leptons pairs for proton-nucleus and nucleus-nucleus collisions for heavy nuclei. In the proton-nucleus we assume the ultrarelativistic proton as a source of photons and estimate the photoproduction of lepton pairs on nuclei at RHIC and LHC energies considering the multiphoton effects associated to multiple rescattering of the projectile photon on the proton of the nucleus. In nucleus - nucleus colllisions we consider the two nuclei as a source of photons. As each scattering contributes with a factor {alpha}Z to the cross section, this contribution must be taken into account for heavy nuclei. We consider the Coulomb corrections to calculate themultiple scatterings and estimate the total cross section for muon and tau pair production in proton-nucleus and nucleus-nucleus collisions at RHIC and LHC energies.

Model for nucleus-nucleus, hadron-nucleus and hadron-proton multiplicity distributions

International Nuclear Information System (INIS)

Singh, C.P.; Shyam, M.; Tuli, S.K.

1986-07-01

A model relating hadron-proton, hadron-nucleus and nucleus-nucleus multiplicity distributions is proposed and some interesting consequences are derived. The values of the parameters are the same for all the processes and are given by the QCD hypothesis of ''universal'' hadronic multiplicities which are found to be asymptotically independent of target and beam in hadronic and current induced reactions in particle physics. (author)

Higgs-boson production in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Anon.

1992-01-01

Cross section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider

Higgs-Boson Production in Nucleus-Nucleus Collisions

Science.gov (United States)

Norbury, John W.

1992-01-01

Cross section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider.

In vivo and in vitro studies of cartilage differentiation in altered gravities

Science.gov (United States)

Montufar-Solis, D.; Duke, P. J.; D'Aunno, D.

The in vivo model our laboratory uses for studies of cartilage differentiation in space is the rat growth plate. Differences between missions, and in rat age and recovery times, provided differing results from each mission. However, in all missions, proliferation and differentiation of chondrocytes in the epiphyseal plate of spaceflown rats was altered as was matrix organization. In vitro systems, necessary complements to in vivo work, provide some advantages over the in vivo situation. In vitro, centrifugation of embryonic limb buds suppressed morphogenesis due to precocious differentiation, and changes in the developmental pattern suggest the involvement of Hox genes. In space, embryonic mouse limb mesenchyme cells differentiating in vitro on IML-1 had smoother membranes and lacked matrix seen in controls. Unusual formations, possibly highly ruffled membranes, were found in flight cultures. These results, coupled with in vivo centrifugation studies, show that in vivo or in vitro, the response of chondrocytes to gravitational changes follows Hert's curve as modified by Simon, i.e. decreased loading decreases differentiation, and increased loading speeds it up, but only to a point. After that, additional increases again slow down chondrogenesis.

Cannabis use is quantitatively associated with nucleus accumbens and amygdala abnormalities in young adult recreational users.

Science.gov (United States)

Gilman, Jodi M; Kuster, John K; Lee, Sang; Lee, Myung Joo; Kim, Byoung Woo; Makris, Nikos; van der Kouwe, Andre; Blood, Anne J; Breiter, Hans C

2014-04-16

Marijuana is the most commonly used illicit drug in the United States, but little is known about its effects on the human brain, particularly on reward/aversion regions implicated in addiction, such as the nucleus accumbens and amygdala. Animal studies show structural changes in brain regions such as the nucleus accumbens after exposure to Δ9-tetrahydrocannabinol, but less is known about cannabis use and brain morphometry in these regions in humans. We collected high-resolution MRI scans on young adult recreational marijuana users and nonusing controls and conducted three independent analyses of morphometry in these structures: (1) gray matter density using voxel-based morphometry, (2) volume (total brain and regional volumes), and (3) shape (surface morphometry). Gray matter density analyses revealed greater gray matter density in marijuana users than in control participants in the left nucleus accumbens extending to subcallosal cortex, hypothalamus, sublenticular extended amygdala, and left amygdala, even after controlling for age, sex, alcohol use, and cigarette smoking. Trend-level effects were observed for a volume increase in the left nucleus accumbens only. Significant shape differences were detected in the left nucleus accumbens and right amygdala. The left nucleus accumbens showed salient exposure-dependent alterations across all three measures and an altered multimodal relationship across measures in the marijuana group. These data suggest that marijuana exposure, even in young recreational users, is associated with exposure-dependent alterations of the neural matrix of core reward structures and is consistent with animal studies of changes in dendritic arborization.

Chronic tinnitus and unipolar brush cell alterations in the cerebellum and dorsal cochlear nucleus.

Science.gov (United States)

Brozoski, Thomas; Brozoski, Daniel; Wisner, Kurt; Bauer, Carol

2017-07-01

Animal model research has shown that the central features of tinnitus, the perception of sound without an acoustic correlate, include elevated spontaneous and stimulus-driven activity, enhanced burst-mode firing, decreased variance of inter-spike intervals, and distortion of tonotopic frequency representation. Less well documented are cell-specific correlates of tinnitus. Unipolar brush cell (UBC) alterations in animals with psychophysical evidence of tinnitus has recently been reported. UBCs are glutamatergic interneurons that appear to function as local-circuit signal amplifiers. UBCs are abundant in the dorsal cochlear nucleus (DCN) and very abundant in the flocculus (FL) and paraflocculus (PFL) of the cerebellum. In the present research, two indicators of UBC structure and function were examined: Doublecortin (DCX) and epidermal growth factor receptor substrate 8 (Eps8). DCX is a protein that binds to microtubules where it can modify their assembly and growth. Eps8 is a cell-surface tyrosine kinase receptor mediating the response to epidermal growth factor; it appears to have a role in actin polymerization as well as cytoskeletal protein interactions. Both functions could contribute to synaptic remodeling. In the present research UBC Eps8 and DCX immunoreactivity (IR) were determined in 4 groups of rats distinguished by their exposure to high-level sound and psychophysical performance: Unexposed, exposed to high-level sound with behavioral evidence of tinnitus, and two exposed groups without behavioral evidence of tinnitus. Compared to unexposed controls, exposed animals with tinnitus had Eps8 IR elevated in their PFL; other structures were not affected, nor was DCX IR affected. This was interpreted as UBC upregulation in animals with tinnitus. Exposure that failed to produce tinnitus did not increase either Eps8 or DCX IR. Rather Eps8 IR was decreased in the FL and DCN of one subgroup (Least-Tinnitus), while DCX IR decreased in the FL of the other subgroup (No

Formation of proton-fragments in hadron-nucleus and nucleus-nucleus collisions at high energies

International Nuclear Information System (INIS)

Bazarov, E.Kh.; Olimov, K.; Petrov, V.I.; Lutpullaev, S.L.

2006-01-01

Full text: The investigation of production of protons in hadron- and nucleus-nucleus interactions is a key problem allowing one to establish the singularities of dynamics of nuclear interactions. The formation of proton-fragments at high energies of colliding particles proceeds within both the interaction of hadrons with nuclei and in the process of decay of the nucleus or its de-excitation at peripheral interactions. At different stages of interaction of impinging particle with target nucleus, the different mechanisms of formation of proton-fragments: the direct knock-out of intranuclear nucleons in the process of high energy cascade of an initial hadron, intranuclear cascade of produced particles, decay of the excited multi-nucleon fragments and of the thermalized remnant nucleus, and the coalescence of nuclear fragments to the new clusters are realized with the certain probability, connected to the interaction parameters (the interaction energy, the parameter of collision, the intranuclear density, the configuration of Fermi momentum of nucleons and clusters of target nucleus et al.). In its turn, the mechanisms of formation of the final nuclear fragments are closely related to the type of excitation of an initial nucleus. The peripheral interactions proceed at small transfers of the momentum of an impinging particle and represent the wide class of reactions covering the processes from diffractive or coulomb collective excitations of the whole nucleus to the direct quasi-elastic knock-out of the separate nucleons. Non-peripheral interactions are caused by comparatively high local transfers of momentum to the intranuclear clusters allowing the development of intranuclear cascade and the asymmetric redistribution of energy of an impinging particle. The central collisions causing the full decay of nucleus on nucleons or few-nucleon fragments, are the limiting case of the maximal development of the intranuclear cascade. The interaction of the initial particles with

Angular momentum and incident-energy dependence of nucleus-nucleus interaction

International Nuclear Information System (INIS)

Yamaguchi, S.

1991-01-01

The purpose of this paper is to understand intuitively the origin of the angular momentum and incident-energy dependence of the nucleus-nucleus interaction on the basis of the totally- antisymmetrized many-body theory. With the aim of understanding the structure of the nucleus-nucleus interaction, we show first that the nucleus-nucleus interaction can be written by the use of the density-distribution function and the phase-space distribution function instead of using the many-body wave function itself. And we show that the structure change of the density-distribution function with the increase of the angular momentum causes the angular momentum dependence of the nucleus-nucleus interaction and that the incident-energy dependence of the nucleus-nucleus interaction originates from the structure change of the phase-space distribution function

Semiclassical model for single-particle transitions in nucleus-nucleus interactions

International Nuclear Information System (INIS)

Milek, B.; Joint Inst. for Nuclear Research, Dubna; Technische Univ., Dresden; Reif, R.; Pham Khan Van; Revai, J.

1990-04-01

A previously elaborated semiclassical one-body model for the dynamics of a single particle, moving in two potentials, in heavy-ion reactions or in fissioning systems has been extended with respect to the inclusion of angular momenta and more realistic separable potentials. The collective relative motion is assumed to proceed along a trajectory which is calculated from classical equations of motion including conservative and phenomenological friction forces. The formalism has been derived involving three-dimensional trajectories for symmetric as well as for asymmetric nucleus-nucleus systems. The model allows for the calculation of correct quantum mechanical transition amplitudes to final bound and continuum states. It has been applied for the investigation of the excitation of a neutron during a fission process, covering also non-statistical differential emission probabilities. From the numerical calculations, using parameters adapted to 252 Cf(sf), one can conclude that in the underlying model without 'sudden' processes the energy spectrum consists of two parts. The low lying component is created in the neck region while a high lying part seems to be governed mainly by the dynamics of the underlying collective motion rather than by the specific initial conditions. (orig.)

New results on nuclear multifragmentation in nucleon-nucleus and nucleus-nucleus collisions at relativistic energies

International Nuclear Information System (INIS)

Besliu, Calin; Jipa, Alexandru; Iliescu, Bogdan; Felea, Daniel

2002-01-01

Some new aspects on the multifragmentation processes in nucleus-nucleus and nucleon-nucleus collisions at high energies are discussed in this work. Experimental data obtained in international collaborations (for example, MULTI Collaboration with KEK Tsukuba (Japan) and SKM 200 Collaboration with JINR Dubna (Russia)) are used to discuss new mechanisms in the target nucleus fragmentation. Correlations with stopping power, participant region size and energy density are included. Comparisons of the experimental results with the predictions of a phenomenological geometric model of intermediate mass fragment multiplicity, caloric curves and angular distributions are also presented. These results are used for global description of the multifragmentation processes in nucleon-nucleus and nucleus-nucleus collisions at relativistic energies. The size of the participant region and the average intermediate mass fragments multiplicity are taken into consideration using the free space probability. A few correlations between the deposited energy in the participant region and stability state of the intermediate mass fragments are presented in this work. The importance of the collision geometry in the multifragmentation processes is stressed. The results suggest different time moments for the incident nucleus fragmentation and for the target nucleus fragmentation. The associated entropies are distinct. (authors)

Optogenetic inhibition of D1R containing nucleus accumbens neurons alters cocaine- mediated regulation of Tiam1

Directory of Open Access Journals (Sweden)

Ramesh eChandra

2013-05-01

Full Text Available Exposure to psychostimulants results in structural and synaptic plasticity in striatal medium spiny neurons (MSNs. These cellular adaptations arise from alterations in genes that are highly implicated in the rearrangement of the actin cytoskeleton, such as Tiam1. Previous studies have demonstrated a crucial role for dopamine receptor 1 (D1-containing striatal MSNs in mediating psychostimulant induced plasticity changes. These D1-MSNs in the nucleus accumbens (NAc positively regulate drug seeking, reward, and locomotor behavioral effects as well as the morphological adaptations of psychostimulant drugs. Here, we demonstrate that rats that actively self-administer cocaine display reduced levels of Tiam1 in the NAc. To further examine the cell type specific contribution to these changes in Tiam1 we used optogenetics to selectively manipulate NAc D1-MSNs or dopamine receptor 2 (D2 expressing MSNs. We find that repeated ChR2 activation of D1-MSNs but not D2-MSNs caused a down-regulation of Tiam1 levels similar to the effects of cocaine. Further, activation of D2-MSNs, which caused a late blunted cocaine-mediated locomotor behavioral response, did not alter Tiam1 levels. We then examined the contribution of D1-MSNs to the cocaine-mediated decrease of Tiam1. Using the light activated chloride pump, eNpHR3.0, we selectively inhibited D1-MSNs during cocaine exposure, which resulted in a behavioral blockade of cocaine-induced locomotor sensitization. Moreover, inhibiting these NAc D1-MSNs during cocaine exposure reversed the down-regulation of Tiam1 gene expression and protein levels. These data demonstrate that altering activity in specific neural circuits with optogenetics can impact the underlying molecular substrates of psychostimulant mediated behavior and function.

Cytoskeleton, endoplasmic reticulum and nucleus alterations in CHO-K1 cell line after Crotalus durissus terrificus (South American rattlesnake venom treatment

Directory of Open Access Journals (Sweden)

B. P. Tamieti

2007-01-01

Full Text Available Snake venoms are toxic to a variety of cell types. However, the intracellular damages and the cell death fate induced by venom are unclear. In the present work, the action of the South American rattlesnake Crotalus durissus terrificus venom on CHO-K1 cell line was analyzed. The cells CHO-K1 were incubated with C. d. terrificus venom (10, 50 and 100g/ml for 1 and 24 hours, and structural alterations of actin filaments, endoplasmic reticulum and nucleus were assessed using specific fluorescent probes and agarose gel electrophoresis for DNA fragmentation. Significant structural changes were observed in all analyzed structures. DNA fragmentation was detected suggesting that, at the concentrations used, the venom induced apoptosis.

Chromatin plasticity as a differentiation index during muscle differentiation of C2C12 myoblasts

International Nuclear Information System (INIS)

Watanabe, Tomonobu M.; Higuchi, Sayaka; Kawauchi, Keiko; Tsukasaki, Yoshikazu; Ichimura, Taro; Fujita, Hideaki

2012-01-01

Highlights: ► Change in the epigenetic landscape during myogenesis was optically investigated. ► Mobility of nuclear proteins was used to state the epigenetic status of the cell. ► Mobility of nuclear proteins decreased as myogenesis progressed in C2C12. ► Differentiation state diagram was developed using parameters obtained. -- Abstract: Skeletal muscle undergoes complicated differentiation steps that include cell-cycle arrest, cell fusion, and maturation, which are controlled through sequential expression of transcription factors. During muscle differentiation, remodeling of the epigenetic landscape is also known to take place on a large scale, determining cell fate. In an attempt to determine the extent of epigenetic remodeling during muscle differentiation, we characterized the plasticity of the chromatin structure using C2C12 myoblasts. Differentiation of C2C12 cells was induced by lowering the serum concentration after they had reached full confluence, resulting in the formation of multi-nucleated myotubes. Upon induction of differentiation, the nucleus size decreased whereas the aspect ratio increased, indicating the presence of force on the nucleus during differentiation. Movement of the nucleus was also suppressed when differentiation was induced, indicating that the plasticity of chromatin changed upon differentiation. To evaluate the histone dynamics during differentiation, FRAP experiment was performed, which showed an increase in the immobile fraction of histone proteins when differentiation was induced. To further evaluate the change in the histone dynamics during differentiation, FCS was performed, which showed a decrease in histone mobility on differentiation. We here show that the plasticity of chromatin decreases upon differentiation, which takes place in a stepwise manner, and that it can be used as an index for the differentiation stage during myogenesis using the state diagram developed with the parameters obtained in this study.

Nuclear surface diffuseness revealed in nucleon-nucleus diffraction

Science.gov (United States)

Hatakeyama, S.; Horiuchi, W.; Kohama, A.

2018-05-01

The nuclear surface provides useful information on nuclear radius, nuclear structure, as well as properties of nuclear matter. We discuss the relationship between the nuclear surface diffuseness and elastic scattering differential cross section at the first diffraction peak of high-energy nucleon-nucleus scattering as an efficient tool in order to extract the nuclear surface information from limited experimental data involving short-lived unstable nuclei. The high-energy reaction is described by a reliable microscopic reaction theory, the Glauber model. Extending the idea of the black sphere model, we find one-to-one correspondence between the nuclear bulk structure information and proton-nucleus elastic scattering diffraction peak. This implies that we can extract both the nuclear radius and diffuseness simultaneously, using the position of the first diffraction peak and its magnitude of the elastic scattering differential cross section. We confirm the reliability of this approach by using realistic density distributions obtained by a mean-field model.

Alteration of keratinocyte differentiation and senescence by the tumor promoter dioxin

International Nuclear Information System (INIS)

Ray, Soma S.; Swanson, Hollie I.

2003-01-01

Exposure to the environmental contaminant dioxin, elicits a variety of responses, which includes tumor promotion, embryotoxicity/teratogenesis, and carcinogenesis in both animals and humans. Many of the effects of dioxin are mediated by the aryl hydrocarbon receptor (AHR), a ligand-activated bHLH (basic helix-loop-helix)/PAS transcription factor. We initiated this study to determine whether dioxin's tumor-promoting activities may lie in its ability to alter proliferation, differentiation, and/or senescence using normal human epidermal keratinocytes (HEKs). Here, we report that dioxin appears to accelerate differentiation as measured by flow cytometry and by increased expression of the differentiation markers involucrin and filaggrin. In addition, dioxin appears to increase proliferation as indicated by an increase in NADH/NADPH production and changes in cell cycle. Finally, dioxin decreases SA (senescence associated) β-galactosidase staining, an indicator of senescence, in the differentiating keratinocytes. These changes were accompanied by decreases in the expression levels of key cell cycle regulatory proteins p53, p16 INK4a , and p14 ARF . Our findings support the idea that dioxin may exert its tumor-promoting actions, in part, by downregulating the expression levels of key tumor suppressor proteins, which may impair the cell's ability to maintain its appropriate cellular status

On the deep inelastic lepton-nucleus scattering

International Nuclear Information System (INIS)

Darbaidze, Ya.Z.; Garsevanishvili, V.R.; Menteshashvili, Z.R.

1979-01-01

Deep inelastic scattering of charged leptons on nuclei is considered in the lowest order in electromagnetic interaction. Expressions for the corresponding differential cross sections are obtained provided the scattered lepton and the fragment of the initial nucleus are detected in coincidence. Structure functions are analyzed by means of the automodelity principle. These functions are considered in the framework of the ''light front'' formalism for many-body systems. A hypothesis is put forward on the scale invariance of structure functions with respect to the xi-variable, which is some complicated dimensionless combination of kinematic invariants. A simple relation of this variable to the momenta of the nucleons inside the initial nucleus is pointed out

Prenatal exposure to urban air nanoparticles in mice causes altered neuronal differentiation and depression-like responses.

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David A Davis

Full Text Available Emerging evidence suggests that excessive exposure to traffic-derived air pollution during pregnancy may increase the vulnerability to neurodevelopmental alterations that underlie a broad array of neuropsychiatric disorders. We present a mouse model for prenatal exposure to urban freeway nanoparticulate matter (nPM. In prior studies, we developed a model for adult rodent exposure to re-aerosolized urban nPM which caused inflammatory brain responses with altered neuronal glutamatergic functions. nPMs are collected continuously for one month from a local freeway and stored as an aqueous suspension, prior to re-aerosolization for exposure of mice under controlled dose and duration. This paradigm was used for a pilot study of prenatal nPM impact on neonatal neurons and adult behaviors. Adult C57BL/6J female mice were exposed to re-aerosolized nPM (350 µg/m(3 or control filtered ambient air for 10 weeks (3×5 hour exposures per week, encompassing gestation and oocyte maturation prior to mating. Prenatal nPM did not alter litter size, pup weight, or postnatal growth. Neonatal cerebral cortex neurons at 24 hours in vitro showed impaired differentiation, with 50% reduction of stage 3 neurons with long neurites and correspondingly more undifferentiated neurons at Stages 0 and 1. Neuron number after 24 hours of culture was not altered by prenatal nPM exposure. Addition of exogenous nPM (2 µg/ml to the cultures impaired pyramidal neuron Stage 3 differentiation by 60%. Adult males showed increased depression-like responses in the tail-suspension test, but not anxiety-related behaviors. These pilot data suggest that prenatal exposure to nPM can alter neuronal differentiation with gender-specific behavioral sequelae that may be relevant to human prenatal exposure to urban vehicular aerosols.

η production in proton-nucleus reactions

International Nuclear Information System (INIS)

Cassing, W.; Batko, G.; Vetter, T.; Wolf, G.

1991-01-01

The production of η-mesons in proton-nucleus reactions is analysed with respect to primary nucleon-nucleon (NN→NN η ) and secondary pion-nucleon (πN→ηN) production processes on the basis of Hartree-Fock groundstate momentum distributions and free on-shell production processes. The folding model adopted compares well for meson production with more involved simulations based on VUU transport equations. Similar to K + production in proton-nucleus reactions the η-mesons are primarily produced by the πN→ηN channel. However, η-mesons are absorbed in nuclei via excitation of the N * (1535) resonance which leads to strong distortions of the primordial spectra. On the other hand, the experimental mass dependence of the differential cross sections might yield information about the in-medium properties of this resonance. (orig.)

Deep brain stimulation of the subthalamic nucleus alters frontal activity during spatial working memory maintenance of patients with Parkinson's disease.

Science.gov (United States)

Mayer, Jutta S; Neimat, Joseph; Folley, Bradley S; Bourne, Sarah K; Konrad, Peter E; Charles, David; Park, Sohee

2016-08-01

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) improves the motor symptoms of Parkinson's disease (PD). The STN may represent an important relay station not only in the motor but also the associative cortico-striato-thalamocortical pathway. Therefore, STN stimulation may alter cognitive functions, such as working memory (WM). We examined cortical effects of STN-DBS on WM in early PD patients using functional near-infrared spectroscopy. The effects of dopaminergic medication on WM were also examined. Lateral frontal activity during WM maintenance was greater when patients were taking dopaminergic medication. STN-DBS led to a trend-level worsening of WM performance, accompanied by increased lateral frontal activity during WM maintenance. These findings suggest that STN-DBS in PD might lead to functional modifications of the basal ganglia-thalamocortical pathway during WM maintenance.

DNA methylation program in developing hippocampus and its alteration by alcohol.

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Yuanyuan Chen

Full Text Available During hippocampal development, the Cornus Ammonis (CA and the dentate gyrus (DG undergo waves of neurogenesis and neuronal migration and maturation independently. This stage is widely known to be vulnerable to environmental stresses, but its underlying mechanism is unclear. Alcohol exposure has been shown to alter the expression of genes that regulate the fate, survival, migration and differentiation of pyramidal and granule cells. Undermining this process might compromise hippocampal development underlying the learning and memory deficits known in Fetal Alcohol Spectrum Disorders (FASD. We have previously demonstrated that DNA methylation was programmed along with neural tube development. Here, we demonstrated that DNA methylation program (DMP proceeded along with hippocampal neuronal differentiation and maturation, and how this DMP was affected by fetal alcohol exposure. C57BL/6 mice were treated with 4% v/v ethanol through a liquid diet along with pair-fed and chow-fed controls from gestation day (E 7 to E16. We found that a characteristic DMP, including 5-methylcytidine (5mC, 5-hydroxylmethylcytidine (5hmC and their binding proteins, led the hippocampal neuronal differentiation and maturation spatiotemporally as indicated by their phenotypic marks in the CA and DG pre- and post-natally. Alcohol hindered the acquisition and progression of methylation marks, and altered the chromatin translocation of these marks in the nucleus, which was correlated with developmental retardation.

Deconfinement of quarks and gluons in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Gorenstein, M.I.

2011-01-01

The energy dependence of hadron production in relativistic nucleus-nucleus collisions reveals the anomalies. They were predicted as the signals of the deconfinement phase transition and observed by NA49 collaboration in Pb+Pb collisions at the CERN SPS. This indicates the onset of the deconfinement in central nucleus-nucleus collisions at about 30 AGeV.

Host cell subversion by Toxoplasma GRA16, an exported dense granule protein that targets the host cell nucleus and alters gene expression.

Science.gov (United States)

Bougdour, Alexandre; Durandau, Eric; Brenier-Pinchart, Marie-Pierre; Ortet, Philippe; Barakat, Mohamed; Kieffer, Sylvie; Curt-Varesano, Aurélie; Curt-Bertini, Rose-Laurence; Bastien, Olivier; Coute, Yohann; Pelloux, Hervé; Hakimi, Mohamed-Ali

2013-04-17

After invading host cells, Toxoplasma gondii multiplies within a parasitophorous vacuole (PV) that is maintained by parasite proteins secreted from organelles called dense granules. Most dense granule proteins remain within the PV, and few are known to access the host cell cytosol. We identify GRA16 as a dense granule protein that is exported through the PV membrane and reaches the host cell nucleus, where it positively modulates genes involved in cell-cycle progression and the p53 tumor suppressor pathway. GRA16 binds two host enzymes, the deubiquitinase HAUSP and PP2A phosphatase, which exert several functions, including regulation of p53 and the cell cycle. GRA16 alters p53 levels in a HAUSP-dependent manner and induces nuclear translocation of the PP2A holoenzyme. Additionally, certain GRA16-deficient strains exhibit attenuated virulence, indicating the importance of these host alterations in pathogenesis. Therefore, GRA16 represents a potentially emerging subfamily of exported dense granule proteins that modulate host function. Copyright © 2013 Elsevier Inc. All rights reserved.

Concentration Sensing by the Moving Nucleus in Cell Fate Determination: A Computational Analysis.

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Varun Aggarwal

Full Text Available During development of the vertebrate neuroepithelium, the nucleus in neural progenitor cells (NPCs moves from the apex toward the base and returns to the apex (called interkinetic nuclear migration at which point the cell divides. The fate of the resulting daughter cells is thought to depend on the sampling by the moving nucleus of a spatial concentration profile of the cytoplasmic Notch intracellular domain (NICD. However, the nucleus executes complex stochastic motions including random waiting and back and forth motions, which can expose the nucleus to randomly varying levels of cytoplasmic NICD. How nuclear position can determine daughter cell fate despite the stochastic nature of nuclear migration is not clear. Here we derived a mathematical model for reaction, diffusion, and nuclear accumulation of NICD in NPCs during interkinetic nuclear migration (INM. Using experimentally measured trajectory-dependent probabilities of nuclear turning, nuclear waiting times and average nuclear speeds in NPCs in the developing zebrafish retina, we performed stochastic simulations to compute the nuclear trajectory-dependent probabilities of NPC differentiation. Comparison with experimentally measured nuclear NICD concentrations and trajectory-dependent probabilities of differentiation allowed estimation of the NICD cytoplasmic gradient. Spatially polarized production of NICD, rapid NICD cytoplasmic consumption and the time-averaging effect of nuclear import/export kinetics are sufficient to explain the experimentally observed differentiation probabilities. Our computational studies lend quantitative support to the feasibility of the nuclear concentration-sensing mechanism for NPC fate determination in zebrafish retina.

Dissection of regulatory networks that are altered in disease via differential co-expression.

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David Amar

Full Text Available Comparing the gene-expression profiles of sick and healthy individuals can help in understanding disease. Such differential expression analysis is a well-established way to find gene sets whose expression is altered in the disease. Recent approaches to gene-expression analysis go a step further and seek differential co-expression patterns, wherein the level of co-expression of a set of genes differs markedly between disease and control samples. Such patterns can arise from a disease-related change in the regulatory mechanism governing that set of genes, and pinpoint dysfunctional regulatory networks. Here we present DICER, a new method for detecting differentially co-expressed gene sets using a novel probabilistic score for differential correlation. DICER goes beyond standard differential co-expression and detects pairs of modules showing differential co-expression. The expression profiles of genes within each module of the pair are correlated across all samples. The correlation between the two modules, however, differs markedly between the disease and normal samples. We show that DICER outperforms the state of the art in terms of significance and interpretability of the detected gene sets. Moreover, the gene sets discovered by DICER manifest regulation by disease-specific microRNA families. In a case study on Alzheimer's disease, DICER dissected biological processes and protein complexes into functional subunits that are differentially co-expressed, thereby revealing inner structures in disease regulatory networks.

Development of global medium-energy nucleon-nucleus optical model potentials

International Nuclear Information System (INIS)

Madland, D.G.; Sierk, A.J.

1997-01-01

The authors report on the development of new global optical model potentials for nucleon-nucleus scattering at medium energies. Using both Schroedinger and Dirac scattering formalisms, the goal is to construct a physically realistic optical potential describing nucleon-nucleus elastic scattering observables for a projectile energy range of (perhaps) 20 meV to (perhaps) 2 GeV and a target mass range of 16 to 209, excluding regions of strong nuclear deformation. They use a phenomenological approach guided by conclusions from recent microscopic studies. The experimental database consists largely of proton-nucleus elastic differential cross sections, analyzing powers, spin-rotation functions, and total reaction cross sections, and neutron-nucleus total cross sections. They will use this database in a nonlinear least-squares adjustment of optical model parameters in both relativistic equivalent Schroedinger (including relativistic kinematics) and Dirac (second-order reduction) formalisms. Isospin will be introduced through the standard Lane model and a relativistic generalization of that model

Activity alterations in the bed nucleus of the stria terminalis and amygdala during threat anticipation in generalized anxiety disorder.

Science.gov (United States)

Buff, Christine; Brinkmann, Leonie; Bruchmann, Maximilian; Becker, Michael P I; Tupak, Sara; Herrmann, Martin J; Straube, Thomas

2017-11-01

Sustained anticipatory anxiety is central to Generalized Anxiety Disorder (GAD). During anticipatory anxiety, phasic threat responding appears to be mediated by the amygdala, while sustained threat responding seems related to the bed nucleus of the stria terminalis (BNST). Although sustained anticipatory anxiety in GAD patients was proposed to be associated with BNST activity alterations, firm evidence is lacking. We aimed to explore temporal characteristics of BNST and amygdala activity during threat anticipation in GAD patients. Nineteen GAD patients and nineteen healthy controls (HC) underwent functional magnetic resonance imaging (fMRI) during a temporally unpredictable threat anticipation paradigm. We defined phasic and a systematic variation of sustained response models for blood oxygen level-dependent responses during threat anticipation, to disentangle temporally dissociable involvement of the BNST and the amygdala. GAD patients relative to HC responded with increased phasic amygdala activity to onset of threat anticipation and with elevated sustained BNST activity that was delayed relative to the onset of threat anticipation. Both the amygdala and the BNST displayed altered responses during threat anticipation in GAD patients, albeit with different time courses. The results for the BNST activation hint towards its role in sustained threat responding, and contribute to a deeper understanding of pathological sustained anticipatory anxiety in GAD. © The Author (2017). Published by Oxford University Press.

Alterations of proliferation and differentiation of hippocampal cells in prenatally stressed rats.

Science.gov (United States)

Sun, Hongli; Su, Qian; Zhang, Huifang; Liu, Weimin; Zhang, Huiping; Ding, Ding; Zhu, Zhongliang; Li, Hui

2015-06-01

To clarify the alterations of proliferation and differentiation of hippocampal cells in prenatally stressed rats. We investigated the impact of prenatal restraint stress on the hipocampal cell proliferation in the progeny with 5-bromo-2'-deoxyuridine (BrdU), which is a marker of proliferating cells and their progeny. In addition, we observed the differentiation of neural stem cells (NSCs) with double labeling of BrdU/neurofilament (NF), BrdU/glial fibrillary acidic protein (GFAP) in the hipocampus. Prenatal stress (PS) increased cell proliferation in the dentate gyrus (DG) only in female and neuron differentiation of newly divided cells in the DG and CA4 in both male and female. Moreover, the NF and GFAP-positive cells, but not the BrdU-positive cells, BrdU/NF and BrdU/GFAP-positive cells, were found frequently in the CA3 and CA1 in the offspring of each group. These results possibly suggest a compensatory adaptive response to neuronal damage or loss in hippocampus induced by PS. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Differential regulation of serotonin-1A receptor stimulated [35S]GTPγS binding in the dorsal raphe nucleus by citalopram and escitalopram

Science.gov (United States)

Rossi, Dania V.; Burke, Teresa F.; Hensler, Julie G.

2008-01-01

The effect of chronic citalopram or escitalopram administration on 5-HT1A receptor function in the dorsal raphe nucleus was determined by measuring [35S]GTPγS binding stimulated by the 5-HT1A receptor agonist (R)-(+)-8-OH-DPAT (1nM-10μM). Although chronic administration of citalopram or escitalopram has been shown to desensitize somatodendritic 5-HT1A autoreceptors, we found that escitalopram treatment decreased the efficacy of 5-HT1A receptors to activate G-proteins, whereas citalopram treatment did not. The binding of [3H]8-OH-DPAT to the coupled, high affinity agonist state of the receptor was not altered by either treatment. Interestingly, escitalopram administration resulted in greater occupancy of serotonin transporter sites as measured by the inhibition of [3H]cyanoimipramine binding. As the binding and action of escitalopram is limited by the inactive enantiomer R-citalopram present in racemic citalopram, we propose that the regulation of 5-HT1A receptor function in the dorsal raphe nucleus at the level of receptor-G protein interaction may be a result of greater inhibition of the serotonin transporter by escitalopram. PMID:18289523

Study of Hadron Production in Hadron-Nucleus and Nucleus-Nucleus Collisions at the CERN SPS

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Klochkov, V; Herve, A E; Kowalski, S; Kaptur, E A; Kowalik, K L; Dominik, W M; Matulewicz, T N; Krasnoperov, A; Feofilov, G; Vinogradov, L; Kovalenko, V; Johnson, S R; Planeta, R J; Rubbia, A; Marton, K; Messerly, B A; Puzovic, J; Bogomilov, M V; Bravar, A; Renfordt, R A E; Deveaux, M; Engel, R R; Grzeszczuk, A; Davis, N; Kuich, M; Lyubushkin, V; Kondratev, V; Kadija, K; Diakonos, F; Slodkowski, M A; Rauch, W H; Pistillo, C; Laszlo, A; Nakadaira, T; Hasegawa, T; Sadovskiy, A; Morozov, S; Petukhov, O; Mathes, H; Roehrich, D; Marcinek, A J; Marino, A D; Grebieszkow, K; Di luise, S; Wlodarczyk, Z; Rybczynski, M A; Wojtaszek-szwarc, A; Nirkko, M C; Sakashita, K; Golubeva, M; Kurepin, A; Manic, D; Kolev, D I; Kisiel, J E; Koziel, M E; Rondio, E; Larsen, D T; Czopowicz, T R; Seyboth, P; Turko, L; Guber, F; Marin, V; Busygina, O; Strikhanov, M; Taranenko, A; Cirkovic, M; Roth, M A; Pulawski, S M; Aduszkiewicz, A M; Bunyatov, S; Vechernin, V; Nagai, Y; Anticic, T; Dynowski, K M; Mackowiak-pawlowska, M K; Stefanek, G; Pavin, M; Fodor, Z P; Nishikawa, K; Tada, M; Blondel, A P P; Stroebele, H W; Posiadala, M Z; Kolesnikov, V; Andronov, E; Zimmerman, E D; Antoniou, N; Majka, Z; Dumarchez, J; Naskret, M; Ivashkin, A; Tsenov, R V; Koziel, M G; Schmidt, K J; Melkumov, G; Popov, B; Panagiotou, A; Richter-was, E M; Morgala, S J; Paolone, V; Damyanova, A; Gazdzicki, M; Unger, M T; Wilczek, A G; Stepaniak, J M; Seryakov, A; Susa, T; Staszel, P P; Brzychczyk, J; Maksiak, B; Tefelski, D B

2007-01-01

The NA61/SHINE (SHINE = SPS Heavy Ion and Neutrino Experiment) experiment is a large acceptance hadron spectrometer at the CERN SPS for the study of the hadronic final states produced in interactions of various beam particles (pions, protons, C, S and In) with a variety of fixed targets at the SPS energies. The main components of the current detector were constructed and used by the NA49 experiment. The physics program of NA61/SHINE consists of three main subjects. In the first stage of data taking (2007-2009) measurements of hadron production in hadron-nucleus interactions needed for neutrino (T2K) and cosmic-ray (Pierre Auger and KASCADE) experiments will be performed. In the second stage (2009-2011) hadron production in proton-proton and proton-nucleus interactions needed as reference data for a better understanding of nucleus-nucleus reactions will be studied. In the third stage (2009-2013) energy dependence of hadron production properties will be measured in nucleus-nucleus collisions as well as in p+p a...

Cell-type specific increases in female hamster nucleus accumbens spine density following female sexual experience.

Science.gov (United States)

Staffend, Nancy A; Hedges, Valerie L; Chemel, Benjamin R; Watts, Val J; Meisel, Robert L

2014-11-01

Female sexual behavior is an established model of a naturally motivated behavior which is regulated by activity within the mesolimbic dopamine system. Repeated activation of the mesolimbic circuit by female sexual behavior elevates dopamine release and produces persistent postsynaptic alterations to dopamine D1 receptor signaling within the nucleus accumbens. Here we demonstrate that sexual experience in female Syrian hamsters significantly increases spine density and alters morphology selectively in D1 receptor-expressing medium spiny neurons within the nucleus accumbens core, with no corresponding change in dopamine receptor binding or protein expression. Our findings demonstrate that previous life experience with a naturally motivated behavior has the capacity to induce persistent structural alterations to the mesolimbic circuit that can increase reproductive success and are analogous to the persistent structural changes following repeated exposure to many drugs of abuse.

Pion production in nucleus--nucleus collisions

International Nuclear Information System (INIS)

Schroeder, L.S.

1975-06-01

Current work on pion production in high-energy nucleus-nucleus collisions is reviewed. The majority of existing data are of the inclusive variety in which a single final state pion is detected. Experimental data are compared and their possible contributions to obtaining new information on nuclear structure is discussed. Various models which attempt to explain the observed single-inclusive-pion spectra either on the basis of a nucleon-nucleus interaction in which Fermi motion is included or on some type of cooperative model are examined. Other areas of interest involving pion production include tests of charge symmetry and pion multiplicities. (9 figures, 1 table) (U.S.)

Presenilin expression during induced differentiation of the human neuroblastoma SH-SY5Y cell line.

Science.gov (United States)

Flood, Fiona; Sundström, Erik; Samuelsson, Eva-Britt; Wiehager, Birgitta; Seiger, Ake; Johnston, Janet A; Cowburn, Richard F

2004-06-01

Human neuroblastoma SH-SY5Y cells stably transfected with both wild-type and exon-9 deleted (deltaE9) presenilin constructs were used to study the role of the presenilin proteins during differentiation. Cells transfected with either wild-type or deltaE9 PS1, of which the latter abolishes normal endoproteolytic cleavage of the protein, showed no obvious differences in their ability to differentiate to a neuronal-like phenotype upon treatment with retinoic acid (RA). A defined pattern of PS1 expression was observed during differentiation with both RA and the phorbol ester TPA. Full-length PS1 was shown to increase dramatically within 5-24 h of RA treatment. TPA gave an earlier and longer lasting increase in full-length PS1 levels. The intracellular distribution pattern of PS1 was markedly altered following RA treatment. Within 24h PS1 was highly up-regulated throughout the cell body around the nucleus. Between 2 and 4 weeks PS1 staining appeared punctate and also localised to the nucleus. Increases in PS1 expression upon treatment with RA and TPA were blocked by treatment with cycloheximide, indicating a role of de-novo protein synthesis in this effect. PS2 expression remained unchanged during differentiation. Levels of full-length PS1 were also seen to increase during neurogenesis and neuronal differentiation in the forebrain of first trimester human foetuses between 6.5 and 11 weeks. These combined observations support the idea that PS1 is involved in neuronal differentiation by a mechanism likely independent of endoproteolysis of the protein.

Stromal-epithelial interactions in aging and cancer: Senescent fibroblasts alter epithelial cell differentiation

Energy Technology Data Exchange (ETDEWEB)

Parrinello, Simona; Coppe, Jean-Philippe; Krtolica, Ana; Campisi, Judith

2004-07-14

Cellular senescence suppresses cancer by arresting cells at risk for malignant tumorigenesis. However, senescent cells also secrete molecules that can stimulate premalignant cells to proliferate and form tumors, suggesting the senescence response is antagonistically pleiotropic. We show that premalignant mammary epithelial cells exposed to senescent human fibroblasts in mice irreversibly lose differentiated properties, become invasive and undergo full malignant transformation. Moreover, using cultured mouse or human fibroblasts and non-malignant breast epithelial cells, we show that senescent fibroblasts disrupt epithelial alveolar morphogenesis, functional differentiation, and branching morphogenesis. Further, we identify MMP-3 as the major factor responsible for the effects of senescent fibroblasts on branching morphogenesis. Our findings support the idea that senescent cells contribute to age-related pathology, including cancer, and describe a new property of senescent fibroblasts--the ability to alter epithelial differentiation--that might also explain the loss of tissue function and organization that is a hallmark of aging.

Perspective of ultrarelativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Specht, H.J.

1985-01-01

The paper concerns the lectures given at the International School of nuclear physics, Erice, 1985, which survey the expectations for the field of ultrarelativistic nucleus-nucleus collisions. The primary motivation for the field, the organization of the lectures, and a description of the NA 34 experiment, are all briefly given. (U.K.)

Formation of light particles in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Zagrebaev, V.; Penionzhkevich, Yu.

1993-01-01

The principal experimental results on the yield of the light charged particles in nucleus-nucleus collisions at the low and intermediate energies are reviewed. Inclusive spectra of light particles and their coincidences with the characteristic KX-rays, γ-rays, neutrons, projectile-like fragments, other light particles, fission fragments, and evaporation residues are analyzed. The main theoretical models used for the description of the light particle formation are briefly outlined together with their merits and shortcomings. The unsolved problems of fast light particle formation, in particular, and of nucleus-nucleus interaction dynamics, on the whole, are discussed with the outlooks of new experiments able to clear up some of these problems. (author) 144 refs., 40 figs., 2 tabs

Global features of nucleus-nucleus collisions in ultrarelativistic domain

International Nuclear Information System (INIS)

Savina, M.V.; Shmatov, S.V.; Slavin, N.V.; Zarubin, P.I.

1998-01-01

HIJING generator simulation of nucleus-nucleus collisions at ultrarelativistic energies is presented. It is shown that the global characteristics of nucleus-nucleus collisions, such as distribution of a charged multiplicity, total and electromagnetic transverse energy over pseudorapidity are rather sensitive to some predictions of models of high-exited nuclear medium formation, namely parton energy losses in dense nuclear matter. These losses result in appearance of a broad maximum in global variable distributions over pseudorapidity. The most profound of this effect occurs at central heavy ion collisions at LHC energy

Scaling phenomenon in relativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Wong, C.Y.; Blankenbecler, R.

1980-01-01

New scaling variables for proton and pion production in relativistic nucleus-nucleus collisions are introduced which are the generalizations of the Feynmann scaling variable. They allow a simple description of the cross sections at forward and backward angles. 2 figures

Nucleus--nucleus potential

International Nuclear Information System (INIS)

Jaqaman, H.R.

1977-01-01

The nucleus--nucleus interaction is studied within the framework of the generator coordinate method that permits an easy incorporation of the full effects of antisymmetrization. It is found that the interaction, as far as the elastic scattering problem is concerned, can be described by a simple effective potential that is equivalent to the original many-body (and hence non-local) problem. The potential is obtained by dividing the wavefunction into a long-range part and a short-range part and requiring the former to satisfy a Schroedinger equation. This enables avoiding dealing with the troublesome short-range part of the wavefunction and provides a direct link with the optical model so that the potential obtained here is equivalent to the real part of the optical potential (the imaginary part is not investigated). The effective potential is found to consist of three parts: an interaction term between the nucleons belonging to different nuclei, a kinetic energy term due to the change in the intrinsic kinetic energy of the system as a result of the antisymmetrization, and finally an l-dependent part. The kinetic energy term is found to be very repulsive and effectively gives a hard core, and is calculated for the α--α and 16 O-- 16 O cases. The full potential is calculated for the α--α case for the S, D, and G partial waves and then used to calculate the corresponding phase shifts that are then compared with experimental results and other microscopic calculations. Finally, some recent results and analyses of fusion and deep inelastic reactions are reviewed that seem to indicate the presence of a hard core in the nucleus--nucleus potential. Such a hard core is present in the potential obtained in the sudden approximation

Hadron-nucleus collisions

International Nuclear Information System (INIS)

Strugalski, Z.

1981-01-01

Qualitative picture of high energy hadron-nucleus collision process, emerging from the analysis of experimental data, is presented. Appropriate description procedure giving a possibility of reproducing various characteristics of this process in terms of the data on elementary hadron-nucleon interaction is proposed. Formula reproducing hadron-nucleus collision cross sections is derived. Inelastic collision cross sections for pion-nucleus and proton-nucleus reactions at wide energy interval are calculated for Pb, Ag, and Al targets. A-dependence of cross sections for pion-nucleus and proton-nucleus collisions at nearly 50 GeV/c momentum were calculated and compared with existing experimental data. Energy dependence of cross sections for hadron-nucleus collisions is determined simply by energy dependence of corresponding cross sections for hadron-nucleon collisions; A-dependence is determined simply by nuclear sizes and nucleon density distributions in nuclei

Altered Functional Connectivity of the Basal Nucleus of Meynert in Mild Cognitive Impairment: A Resting-State fMRI Study

Directory of Open Access Journals (Sweden)

Hui Li

2017-05-01

Full Text Available Background: Cholinergic dysfunction plays an important role in mild cognitive impairment (MCI. The basal nucleus of Meynert (BNM provides the main source of cortical cholinergic innervation. Previous studies have characterized structural changes of the cholinergic basal forebrain in individuals at risk of developing Alzheimer’s disease (AD. However, whether and how functional connectivity of the BNM (BNM-FC is altered in MCI remains unknown.Objective: The aim of this study was to identify alterations in BNM-FC in individuals with MCI as compared to healthy controls (HCs, and to examine the relationship between these alterations with neuropsychological measures in individuals with MCI.Method: One-hundred-and-one MCI patients and 103 HCs underwent resting-state functional magnetic resonance imaging (rs-fMRI. Imaging data were processed with SPM8 and CONN software. BNM-FC was examined via correlation in low frequency fMRI signal fluctuations between the BNM and all other brain voxels. Group differences were examined with a covariance analysis with age, gender, education level, mean framewise displacement (FD and global correlation (GCOR as nuisance covariates. Pearson’s correlation was conducted to evaluate the relationship between the BNM-FC and clinical assessments.Result: Compared with HCs, individuals with MCI showed significantly decreased BNM-FC in the left insula extending into claustrum (insula/claustrum. Furthermore, greater decrease in BNM-FC with insula/claustrum was associated with more severe impairment in immediate recall during Auditory Verbal Learning Test (AVLT in MCI patients.Conclusion: MCI is associated with changes in BNM-FC to the insula/claustrum in relation to cognitive impairments. These new findings may advance research of the cholinergic bases of cognitive dysfunction during healthy aging and in individuals at risk of developing AD.

Nuclear collective flow from gaussian fits to triple differential distributions

International Nuclear Information System (INIS)

Gosset, J.; Babinet, R.; Cavata, C.; Marco, M. de; Demoulins, M.; Fanet, H.; Fodor, Z.; L'Hote, D.; Lucas, B.

1990-01-01

A simple characterization of triple differential cross sections is needed for a systematic study of the nuclear matter collective flow in relativistic nucleus-nucleus collisions. Our analysis is based upon a fitting procedure, so that the triple differential distributions need not be measured in the whole momentum space. If the detector acceptance eliminates most spectator particles or if it is artificially restricted for doing so, this method leads to a flow characterization of the participant nuclear matter. The center-of-mass triple-differential momentum distributions are fitted to a simple analytical shape, namely an anisotropic Gaussian distribution. The adjusted parameters (flow angle and aspect ratios) are corrected for uncertainty in the event-by-event determination of the reaction plane azimuth (finite-number effects). Results are presented for neon-nucleus and argon-nucleus collisions at incident energy between 400 and 800 MeV per nucleon. Flow is already significant for light systems, and depends clearly upon the impact parameter

The Nucleus Accumbens: Mechanisms of Addiction across Drug Classes Reflect the Importance of Glutamate Homeostasis

Science.gov (United States)

Heinsbroek, J. A.; Gipson, C. D.; Kupchik, Y. M.; Spencer, S.; Smith, A. C. W.; Roberts-Wolfe, D.; Kalivas, P. W.

2016-01-01

The nucleus accumbens is a major input structure of the basal ganglia and integrates information from cortical and limbic structures to mediate goal-directed behaviors. Chronic exposure to several classes of drugs of abuse disrupts plasticity in this region, allowing drug-associated cues to engender a pathologic motivation for drug seeking. A number of alterations in glutamatergic transmission occur within the nucleus accumbens after withdrawal from chronic drug exposure. These drug-induced neuroadaptations serve as the molecular basis for relapse vulnerability. In this review, we focus on the role that glutamate signal transduction in the nucleus accumbens plays in addiction-related behaviors. First, we explore the nucleus accumbens, including the cell types and neuronal populations present as well as afferent and efferent connections. Next we discuss rodent models of addiction and assess the viability of these models for testing candidate pharmacotherapies for the prevention of relapse. Then we provide a review of the literature describing how synaptic plasticity in the accumbens is altered after exposure to drugs of abuse and withdrawal and also how pharmacological manipulation of glutamate systems in the accumbens can inhibit drug seeking in the laboratory setting. Finally, we examine results from clinical trials in which pharmacotherapies designed to manipulate glutamate systems have been effective in treating relapse in human patients. Further elucidation of how drugs of abuse alter glutamatergic plasticity within the accumbens will be necessary for the development of new therapeutics for the treatment of addiction across all classes of addictive substances. PMID:27363441

The Nucleus Accumbens: Mechanisms of Addiction across Drug Classes Reflect the Importance of Glutamate Homeostasis.

Science.gov (United States)

Scofield, M D; Heinsbroek, J A; Gipson, C D; Kupchik, Y M; Spencer, S; Smith, A C W; Roberts-Wolfe, D; Kalivas, P W

2016-07-01

The nucleus accumbens is a major input structure of the basal ganglia and integrates information from cortical and limbic structures to mediate goal-directed behaviors. Chronic exposure to several classes of drugs of abuse disrupts plasticity in this region, allowing drug-associated cues to engender a pathologic motivation for drug seeking. A number of alterations in glutamatergic transmission occur within the nucleus accumbens after withdrawal from chronic drug exposure. These drug-induced neuroadaptations serve as the molecular basis for relapse vulnerability. In this review, we focus on the role that glutamate signal transduction in the nucleus accumbens plays in addiction-related behaviors. First, we explore the nucleus accumbens, including the cell types and neuronal populations present as well as afferent and efferent connections. Next we discuss rodent models of addiction and assess the viability of these models for testing candidate pharmacotherapies for the prevention of relapse. Then we provide a review of the literature describing how synaptic plasticity in the accumbens is altered after exposure to drugs of abuse and withdrawal and also how pharmacological manipulation of glutamate systems in the accumbens can inhibit drug seeking in the laboratory setting. Finally, we examine results from clinical trials in which pharmacotherapies designed to manipulate glutamate systems have been effective in treating relapse in human patients. Further elucidation of how drugs of abuse alter glutamatergic plasticity within the accumbens will be necessary for the development of new therapeutics for the treatment of addiction across all classes of addictive substances. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

Differential Dopamine Regulation of Ca2+ Signaling and Its Timing Dependence in the Nucleus Accumbens

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Immani Swapna

2016-04-01

Full Text Available Dopamine action in the nucleus accumbens (NAc is thought to drive appetitive behavior and Pavlovian reward learning. However, it remains controversial how dopamine achieves these behavioral effects by regulating medium spiny projection neurons (MSNs of the NAc, especially on a behaviorally relevant timescale. Metabotropic glutamate receptor (mGluR-induced Ca2+ signaling dependent on the Ca2+- releasing messenger inositol 1,4,5-triphosphate (IP3 plays a critical role in controlling neuronal excitability and synaptic plasticity. Here, we show that transient dopamine application facilitates mGluR/IP3-induced Ca2+ signals within a time window of ∼2–10 s in a subpopulation of MSNs in the NAc core. Dopamine facilitation of IP3-induced Ca2+ signaling is mediated by D1 dopamine receptors. In dopamine-insensitive MSNs, activation of A2A adenosine receptors causes enhancement of IP3-evoked Ca2+ signals, which is reversed by D2 dopamine receptor activation. These results show that dopamine differentially regulates Ca2+ signaling on the order of seconds in two distinct MSN subpopulations.

Differential regulation of serotonin-1A receptor-stimulated [35S]GTP gamma S binding in the dorsal raphe nucleus by citalopram and escitalopram.

Science.gov (United States)

Rossi, Dania V; Burke, Teresa F; Hensler, Julie G

2008-03-31

The effect of chronic citalopram or escitalopram administration on 5-HT1A receptor function in the dorsal raphe nucleus was determined by measuring [35S]GTP gamma S binding stimulated by the 5-HT1A receptor agonist (R)-(+)-8-OH-DPAT (1nM-10 microM). Although chronic administration of citalopram or escitalopram has been shown to desensitize somatodendritic 5-HT1A autoreceptors, we found that escitalopram treatment decreased the efficacy of 5-HT1A receptors to activate G proteins, whereas citalopram treatment did not. The binding of [3H]8-OH-DPAT to the coupled, high affinity agonist state of the receptor was not altered by either treatment. Interestingly, escitalopram administration resulted in greater occupancy of serotonin transporter sites as measured by the inhibition of [3H]cyanoimipramine binding. As the binding and action of escitalopram is limited by the inactive enantiomer R-citalopram present in racemic citalopram, we propose that the regulation of 5-HT1A receptor function in the dorsal raphe nucleus at the level of receptor-G protein interaction may be a result of greater inhibition of the serotonin transporter by escitalopram.

The imaginary part of the nucleus - nucleus optical potential

International Nuclear Information System (INIS)

Phatak, S.C.; Sinha, B.

1978-01-01

The contribution to the imaginary nucleus - nucleus optical potential has been estimated by evaluating the energy - conserving seocond-order term in the perturbation series. The incoming nuclear field is supposed to excite nucleons in a nucleus in this calculation and the nuclear excitations are approximated by particle-hole excitations in a Fermi gas. The resulting imaginary potential compares favourably with phenomenological potentials. (author)

REST/NRSF Knockdown Alters Survival, Lineage Differentiation and Signaling in Human Embryonic Stem Cells.

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Kaushali Thakore-Shah

Full Text Available REST (RE1 silencing transcription factor, also known as NRSF (neuron-restrictive silencer factor, is a well-known transcriptional repressor of neural genes in non-neural tissues and stem cells. Dysregulation of REST activity is thought to play a role in diverse diseases including epilepsy, cancer, Down's syndrome and Huntington's disease. The role of REST/NRSF in control of human embryonic stem cell (hESC fate has never been examined. To evaluate the role of REST in hESCs we developed an inducible REST knockdown system and examined both growth and differentiation over short and long term culture. Interestingly, we have found that altering REST levels in multiple hESC lines does not result in loss of self-renewal but instead leads to increased survival. During differentiation, REST knockdown resulted in increased MAPK/ERK and WNT signaling and increased expression of mesendoderm differentiation markers. Therefore we have uncovered a new role for REST in regulation of growth and early differentiation decisions in human embryonic stem cells.

Legumain Regulates Differentiation Fate of Human Bone Marrow Stromal Cells and Is Altered in Postmenopausal Osteoporosis

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Abbas Jafari

2017-02-01

Full Text Available Secreted factors are a key component of stem cell niche and their dysregulation compromises stem cell function. Legumain is a secreted cysteine protease involved in diverse biological processes. Here, we demonstrate that legumain regulates lineage commitment of human bone marrow stromal cells and that its expression level and cellular localization are altered in postmenopausal osteoporotic patients. As shown by genetic and pharmacological manipulation, legumain inhibited osteoblast (OB differentiation and in vivo bone formation through degradation of the bone matrix protein fibronectin. In addition, genetic ablation or pharmacological inhibition of legumain activity led to precocious OB differentiation and increased vertebral mineralization in zebrafish. Finally, we show that localized increased expression of legumain in bone marrow adipocytes was inversely correlated with adjacent trabecular bone mass in a cohort of patients with postmenopausal osteoporosis. Our data suggest that altered proteolytic activity of legumain in the bone microenvironment contributes to decreased bone mass in postmenopausal osteoporosis.

Proton-nucleus dynamics at ultra-relativistic energies

International Nuclear Information System (INIS)

McCubbin, N.A.

1988-01-01

Some of the basic properties of proton-nucleus (pA) collisions at ultrarelativistic energies are reviewed. These include total and 'partonic' cross-sections, and the differential cross-sections as functions of rapidity, transverse energy, and particle p T , with particular emphasis in all cases on the A dependence. The aim is to introduce a nuclear physics audience to the main trends and ideas; experts in the field will find nothing very new here. (orig.)

Hepatocellular differentiation status is characterized by distinct subnuclear localization and form of the chanzyme TRPM7.

Science.gov (United States)

Ogunrinde, Adenike; Pereira, Robyn D; Beaton, Natalie; Lam, D Hung; Whetstone, Christiane; Hill, Ceredwyn E

The channel-kinase TRPM7 is important for the survival, proliferation, and differentiation, of many cell types. Both plasma membrane channel activity and kinase function are implicated in these roles. Channel activity is greater in less differentiated hepatoma cells compared with non-dividing, terminally differentiated adult hepatocytes, suggesting differences in protein expression and/or localization. We used electrophysiological and immunofluorescence approaches to establish whether hepatocellular differentiation is associated with altered TRPM7 expression. Mean outward current decreased by 44% in WIF-B hepatoma cells incubated with the established hepatic differentiating factors oncostatin M/dexamethasone for 1-8 days. Pre-incubation with pyridone 6, a pan-JAK inhibitor, blocked the current reduction. An antibody targeted to the C-terminus of TRPM7 labelled the cytoplasm in WIF-B cells and intact rat liver. Significant label also localized to the nuclear envelope (NE), with relatively more detected in adult hepatocytes compared with WIF-B cells. Hepatoma cells also exhibited nucleoplasmic labelling with intense signal in the nucleolus. The endogenous labelling pattern closely resembles that of HEK293T cells heterologously expressing a TRPM7 kinase construct containing a putative nucleolar localization sequence. These results suggest that TRPM7 form and distribution between the plasma membrane and nucleus, rather than expression, is altered in parallel with differentiation status in rat hepatic cells. Copyright © 2017 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

Quasi-elastic shadowing in nucleus-nucleus elastic scattering

Energy Technology Data Exchange (ETDEWEB)

Dymarz, R; Malecki, A [Institute of Nuclear Physics, Krakow (Poland); Gluski, K [Institute of Nuclear Research, Warsaw (Poland); Picchi, P [Turin Univ. (Italy). Ist. di Fisica; Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica)

1979-01-06

The complete evaluation of the Glauber multiple-scattering series for nucleus-nucleus collisions is a very difficult task and that is why various approximate formulae were proposed. In this work some of these approximations are discussed.

Plastid-to-Nucleus Retrograde Signals Are Essential for the Expression of Nuclear Starch Biosynthesis Genes during Amyloplast Differentiation in Tobacco BY-2 Cultured Cells1[W][OA

Science.gov (United States)

Enami, Kazuhiko; Ozawa, Tomoki; Motohashi, Noriko; Nakamura, Masayuki; Tanaka, Kan; Hanaoka, Mitsumasa

2011-01-01

Amyloplasts, a subtype of plastid, are found in nonphotosynthetic tissues responsible for starch synthesis and storage. When tobacco (Nicotiana tabacum) Bright Yellow-2 cells are cultured in the presence of cytokinin instead of auxin, their plastids differentiate from proplastids to amyloplasts. In this program, it is well known that the expression of nucleus-encoded starch biosynthesis genes, such as ADP-Glucose Pyrophosphorylase (AgpS) and Granule-Bound Starch Synthase (GBSS), is specifically induced. In this study, we investigated the roles of plastid gene expression in amyloplast differentiation. Microarray analysis of plastid genes revealed that no specific transcripts were induced in amyloplasts. Nevertheless, amyloplast development accompanied with starch biosynthesis was drastically inhibited in the presence of plastid transcription/translation inhibitors. Surprisingly, the expression of nuclear AgpS and GBSS was significantly repressed by the addition of these inhibitors, suggesting that a plastid-derived signal(s) that reflects normal plastid gene expression was essential for nuclear gene expression. A series of experiments was performed to examine the effects of intermediates and inhibitors of tetrapyrrole biosynthesis, since some of the intermediates have been characterized as candidates for plastid-to-nucleus retrograde signals. Addition of levulinic acid, an inhibitor of tetrapyrrole biosynthesis, resulted in the up-regulation of nuclear AgpS and GBSS gene expression as well as starch accumulation, while the addition of heme showed opposite effects. Thus, these results indicate that plastid transcription and/or translation are required for normal amyloplast differentiation, regulating the expression of specific nuclear genes by unknown signaling mechanisms that can be partly mediated by tetrapyrrole intermediates. PMID:21771917

High density QCD and nucleus-nucleus scattering deeply in the saturation region

International Nuclear Information System (INIS)

Kormilitzin, Andrey; Levin, Eugene; Miller, Jeremy S.

2011-01-01

In this paper we solve the equations that describe nucleus-nucleus scattering, in high density QCD, in the framework of the BFKL Pomeron Calculus. We found that (i) the contribution of short distances to the opacity for nucleus-nucleus scattering dies at high energies, (ii) the opacity tends to unity at high energy, and (iii) the main contribution that survives comes from soft (long distance) processes for large values of the impact parameter. The corrections to the opacity Ω(Y,b)=1 were calculated and it turns out that they have a completely different form, namely (1-Ω→exp(-Const√(Y))) than the opacity that stems from the Balitsky-Kovchegov equation, which is (1-Ω→exp(-ConstY 2 )). We reproduce the formula for the nucleus-nucleus cross section that is commonly used in the description of nucleus-nucleus scattering, and there is no reason why it should be correct in the Glauber-Gribov approach.

Control of cell nucleus shapes via micropillar patterns.

Science.gov (United States)

Pan, Zhen; Yan, Ce; Peng, Rong; Zhao, Yingchun; He, Yao; Ding, Jiandong

2012-02-01

We herein report a material technique to control the shapes of cell nuclei by the design of the microtopography of substrates to which the cells adhere. Poly(D,L-lactide-co-glycolide) (PLGA) micropillars or micropits of a series of height or depth were fabricated, and some surprising self deformation of the nuclei of bone marrow stromal cells (BMSCs) was found in the case of micropillars with a sufficient height. Despite severe nucleus deformation, BMSCs kept the ability of proliferation and differentiation. We further demonstrated that the shapes of cell nuclei could be regulated by the appropriate micropillar patterns. Besides circular and elliptoid shapes, some unusual nucleus shapes of BMSCs have been achieved, such as square, cross, dumbbell, and asymmetric sphere-protrusion. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

GENETIC DIFFERENTIATION AMONG POPULATIONS OF Chromobotia macracanthus BLEEKER FROM SUMATRA AND KALIMANTAN BASED ON SEQUENCING GENE OF MTDNA CYTOCHROME B AND NUCLEUS DNA RAG2

Directory of Open Access Journals (Sweden)

Sudarto Sudarto

2008-12-01

Full Text Available Research on genetic differentiation among populations of Chromobotia macracanthus Bleeker from Sumatra, based on sequencing gene of mtDNA Cytochrome b and nucleus DNA RAG2 has been done. The objectives of the study were to obtain the representation of genetic differentiation among population of clown loach fishes or botia (Chromobotia macracanthus from Sumatra and Kalimantan and to estimate the time divergence of both population group of botia. Samples of botia population were taken from 3 rivers in Sumatra namely Batanghari, Musi, and Tulang Bawang and one river from Kalimantan namely Kapuas. The genetic analysis was based on the sequencing of mtDNA Cytochrome b and nucleus DNA RAG2. The statistical analysis was done by using APE package on R language. The parameters observed were: nucleotide diversity, genetic distance, and neighbor-joining tree. The result showed that the highest nucleotide diversity was fish population of Musi, while the other two populations, Tulang Bawang (Sumatra and Kapuas (Kalimantan, were considered as the lowest genetic diversity especially based on nucleus DNA RAG2 sequencing. Based on mtDNA Cytochrome-b sequencing, the most distinct population among those populations based on genetic distance were fish populations of Musi and Kapuas. According to the result of neighbor-joining tree analysis, the populations of botia were classified into two groups namely group of Sumatra and group of Kalimantan. The estimation of time divergence among group of population of Sumatra and Kalimantan based on mtDNA Cytochrome b was about 9.25—9.46 million years (Miocene era. The high genetic differences between groups of Sumatra and Kalimantan suggested that the effort of restocking botia from Sumatra into Kalimantan has to be done carefully, because it may disturb the gene originality of both botia populations.

Extracellular Protease Inhibition Alters the Phenotype of Chondrogenically Differentiating Human Mesenchymal Stem Cells (MSCs) in 3D Collagen Microspheres.

Science.gov (United States)

Han, Sejin; Li, Yuk Yin; Chan, Barbara Pui

2016-01-01

Matrix remodeling of cells is highly regulated by proteases and their inhibitors. Nevertheless, how would the chondrogenesis of mesenchymal stem cells (MSCs) be affected, when the balance of the matrix remodeling is disturbed by inhibiting matrix proteases, is incompletely known. Using a previously developed collagen microencapsulation platform, we investigated whether exposing chondrogenically differentiating MSCs to intracellular and extracellular protease inhibitors will affect the extracellular matrix remodeling and hence the outcomes of chondrogenesis. Results showed that inhibition of matrix proteases particularly the extracellular ones favors the phenotype of fibrocartilage rather than hyaline cartilage in chondrogenically differentiating hMSCs by upregulating type I collagen protein deposition and type II collagen gene expression without significantly altering the hypertrophic markers at gene level. This study suggests the potential of manipulating extracellular proteases to alter the outcomes of hMSC chondrogenesis, contributing to future development of differentiation protocols for fibrocartilage tissues for intervertebral disc and meniscus tissue engineering.

Extracellular Protease Inhibition Alters the Phenotype of Chondrogenically Differentiating Human Mesenchymal Stem Cells (MSCs in 3D Collagen Microspheres.

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Sejin Han

Full Text Available Matrix remodeling of cells is highly regulated by proteases and their inhibitors. Nevertheless, how would the chondrogenesis of mesenchymal stem cells (MSCs be affected, when the balance of the matrix remodeling is disturbed by inhibiting matrix proteases, is incompletely known. Using a previously developed collagen microencapsulation platform, we investigated whether exposing chondrogenically differentiating MSCs to intracellular and extracellular protease inhibitors will affect the extracellular matrix remodeling and hence the outcomes of chondrogenesis. Results showed that inhibition of matrix proteases particularly the extracellular ones favors the phenotype of fibrocartilage rather than hyaline cartilage in chondrogenically differentiating hMSCs by upregulating type I collagen protein deposition and type II collagen gene expression without significantly altering the hypertrophic markers at gene level. This study suggests the potential of manipulating extracellular proteases to alter the outcomes of hMSC chondrogenesis, contributing to future development of differentiation protocols for fibrocartilage tissues for intervertebral disc and meniscus tissue engineering.

Development of a Mobile Ice Nucleus Counter

Energy Technology Data Exchange (ETDEWEB)

Kok, Gregory [Droplet Measurement Technologies, Boulder, CO (United States); Kulkarni, Gourihar [Droplet Measurement Technologies, Boulder, CO (United States)

2014-07-10

An ice nucleus counter has been constructed. The instrument uses built-in refrigeration systems for wall cooling. A cascade refrigeration system will allow the cold wall to operate as low as -70°C, and a single stage system can operate the warm wall at -45C. A unique optical particle counter has been constructed using polarization detection of the scattered light. This allows differentiation of the particles exiting the chamber to determine if they are ice or liquid.

Optical model calculation of neutron-nucleus scattering cross sections

International Nuclear Information System (INIS)

Smith, M.E.; Camarda, H.S.

1980-01-01

A program to calculate the total, elastic, reaction, and differential cross section of a neutron interacting with a nucleus is described. The interaction between the neutron and the nucleus is represented by a spherically symmetric complex potential that includes spin-orbit coupling. This optical model problem is solved numerically, and is treated with the partial-wave formalism of scattering theory. The necessary scattering theory required to solve this problem is briefly stated. Then, the numerical methods used to integrate the Schroedinger equation, calculate derivatives, etc., are described, and the results of various programming tests performed are presented. Finally, the program is discussed from a user's point of view, and it is pointed out how and where the program (OPTICAL) can be changed to satisfy particular needs

Onuf's nucleus X

DEFF Research Database (Denmark)

Schrøder, H D

1981-01-01

in the length of the nucleus was observed. Based on the cytoarchitecture the nucleus could be divided in three parts, a cranial, a dorsomedial and a ventrolateral. All parts of the nucleus consisted of chromatin-rich medium-sized neurons, and apparent direct appositions between different cells bodies as well...

Classifiers for centrality determination in proton-nucleus and nucleus-nucleus collisions

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Altsybeev Igor

2017-01-01

Full Text Available Centrality, as a geometrical property of the collision, is crucial for the physical interpretation of nucleus-nucleus and proton-nucleus experimental data. However, it cannot be directly accessed in event-by-event data analysis. Common methods for centrality estimation in A-A and p-A collisions usually rely on a single detector (either on the signal in zero-degree calorimeters or on the multiplicity in some semi-central rapidity range. In the present work, we made an attempt to develop an approach for centrality determination that is based on machine-learning techniques and utilizes information from several detector subsystems simultaneously. Different event classifiers are suggested and evaluated for their selectivity power in terms of the number of nucleons-participants and the impact parameter of the collision. Finer centrality resolution may allow to reduce impact from so-called volume fluctuations on physical observables being studied in heavy-ion experiments like ALICE at the LHC and fixed target experiment NA61/SHINE on SPS.

Partial inelasticity coefficients of negative pions produced in hadron-nucleus and nucleus-nucleus collisions at high energies

International Nuclear Information System (INIS)

OLIMOV, K.; LUTPULLAEV, S.L.; PETROV, V.I.; OLIMOV, A.K.

2015-01-01

New experimental data on the partial inelasticity coefficients of negative pions produced in "1"6Op-collisions at 3.25 A GeV/s, pC-interactions at 4.2 and 9.9 GeV/s, and d,α,C(C)-collisions at 4.2 A GeV/s are presented. It is established that the behavior of partial inelasticity coefficients of pions at intermediate energies (<10 GeV) in hadron-nucleus collisions has a transitional character, reaching the limiting value at ultrahigh energies. It is shown that the mean values of partial inelasticity coefficients of pions produced in nucleus-nucleus collisions decrease with an increase in mass number of the projectile nucleus. (authors)

Diabatic interaction potential for nucleus-nucleus collisions

International Nuclear Information System (INIS)

Noerenberg, W.; Lukasiak, A.

1984-01-01

Within a refined method for the construction of diabatic states allowing for the treatment of the full spin-orbit coupling, characteristic features of the diabatic potential for nucleus-nucleus collisions are investigated. Approximately 90% of the strong repulsion results from diabatic particle-hole excitations, while only 10% is due to compression. The diabatic interaction potential describes a physical situation intermediate between adiabatic and sudden approximations. (orig.)

S36. DIFFERENTIAL ENCODING OF SENSITIZATION AND CROSS SENSITIZATION TO PSYCHOSTIMULANTS AND ANTIPSYCHOTICS IN NUCLEUS ACCUMBENS D1- AND D2- RECEPTOR EXPRESSING MEDIUM SPINY NEURONS

Science.gov (United States)

Amato, Davide; Heinsbroek, Jasper; Kalivas, Peter W

2018-01-01

Abstract Background Nearly half of all individuals diagnosed with schizophrenia abuse addictive substances such as cocaine. Currently, the neurobiological mechanisms in patients with schizophrenia that lead to cocaine abuse are unknown. A possible explanation for the co-morbidity between schizophrenia and addiction is that the rewarding properties of cocaine reverse the diminished motivational drive caused by chronic antipsychotic regimen. Moreover, chronic antipsychotic treatment can sensitize and amplify cocaine rewarding effects and exacerbate psychoses. Methods The rewarding properties of cocaine are attributed to the differential effects of dopamine on D1 and D2 receptor-expressing medium spiny neurons (MSNs) in the nucleus accumbens (NAc). Using in vivo Ca2+ miniature microscopic imaging, we characterize the role of D1 and D2 MSN in mono- and a cross- sensitization paradigms. D1- and D2-Cre mice were injected with a Cre dependent calcium indicator (gCaMP6f) and implanted with a gradient index (GRIN) lens above the nucleus accumbens and calcium activity was recorded using a head mounted miniature microscope. Cocaine sensitization was measured after a classic repeated cocaine regiment and antipsychotic and psychostimulant cross-sensitization was measured by a single cocaine injection after chronic pre-treatment with haloperidol. Results We found that both D1-MSN and D2-MSN populations are modulated by initial cocaine experience and further modulated during the expression of cocaine sensitization. A subpopulation of D1-MSN displayed initial activation, but reduced activity during the expression of sensitization. By contrast, the majority of D2-MSNs were suppressed by initial cocaine experience, but became active during the expression of sensitization. Furthermore, activity of D1- and D2-MSNs bidirectionally related with the observed behavioral responses to cocaine. Cross-sensitization following haloperidol treatment led to increased behavioral responses to

Classical gluon production amplitude for nucleus-nucleus collisions:First saturation correction in the projectile

International Nuclear Information System (INIS)

Chirilli, Giovanni A.; Kovchegov, Yuri V.; Wertepny, Douglas E.

2015-01-01

We calculate the classical single-gluon production amplitude in nucleus-nucleus collisions including the first saturation correction in one of the nuclei (the projectile) while keeping multiple-rescattering (saturation) corrections to all orders in the other nucleus (the target). In our approximation only two nucleons interact in the projectile nucleus: the single-gluon production amplitude we calculate is order-g"3 and is leading-order in the atomic number of the projectile, while resumming all order-one saturation corrections in the target nucleus. Our result is the first step towards obtaining an analytic expression for the first projectile saturation correction to the gluon production cross section in nucleus-nucleus collisions.

Altered neuronal firing pattern of the basal ganglia nucleus plays a role in levodopa-induced dyskinesia in patients with Parkinson's disease

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Xiaoyu eLi

2015-11-01

Full Text Available Background: Levodopa therapy alleviates the symptoms of Parkinson's disease (PD, but long-term treatment often leads to motor complications such as levodopa-induced dyskinesia (LID. Aim: To explore the neuronal activity in the basal ganglia nuclei in patients with PD and LID. Methods: Thirty patients with idiopathic PD (age, 55.1±11.0 years; disease duration, 8.7±5.6 years were enrolled between August 2006 and August 2013 at the Xuanwu Hospital, Capital Medical University, China. Their Hoehn and Yahr scores ranged from 2 to 4 and their UPDRS III scores were 28.5±5.2. Fifteen of them had severe LID (UPDRS IV scores of 6.7±1.6. Microelectrode recording was performed in the globus pallidus internus (GPi and subthalamic nucleus (STN during pallidotomy (n=12 or STN deep brain stimulation (DBS; bilateral, n=12; unilateral, n=6. The firing patterns and frequencies of various cell types were analyzed by assessing single cell interspike intervals (ISIs and the corresponding coefficient of variation (CV. Results: A total of 295 neurons were identified from the GPi (n=12 and STN (n=18. These included 26 (8.8% highly grouped discharge, 30 (10.2% low frequency firing, 78 (26.4% rapid tonic discharge, 103 (34.9% irregular activity, and 58 (19.7% tremor-related activity. There were significant differences between the two groups (P<0.05 for neurons with irregular firing, highly irregular cluster-like firing, and low-frequency firing. Conclusion: Altered neuronal activity was observed in the basal ganglia nucleus of GPi and STN, and may play important roles in the pathophysiology of PD and LID.

Differential Contributions of Nucleus Accumbens Subregions to Cue-Guided Risk/Reward Decision Making and Implementation of Conditional Rules.

Science.gov (United States)

Floresco, Stan B; Montes, David R; Tse, Maric M T; van Holstein, Mieke

2018-02-21

associated with neuropsychiatric disorders, such as attention deficit hyperactivity disorder and schizophrenia, which in turn has been linked to aberrant processing in the nucleus accumbens. However, many preclinical studies have often assessed risk/reward decision making in the absence of explicit cues. The current study fills that gap by using a novel task that allows for the assessment of cue-guided risk/reward decision making in rodents. Our findings identified distinct yet complementary roles for the medial versus lateral portions of this nucleus that provide a broader understanding of the differential contributions it makes to decision making and reward seeking guided by discriminative stimuli. Copyright © 2018 the authors 0270-6474/18/381901-14$15.00/0.

K+-nucleus interaction

International Nuclear Information System (INIS)

Gibbs, W.R.

1984-01-01

The K + -nucleus system is reviewed and comparison with data is made. The principal conclusions are that the theoretical uncertainties in relating the K + -nucleus interaction to the K + -nucleon interaction are very small and hence the positive kaon makes an excellent probe of the nucleus. It is suggested that this particle may be more sensitive to non-nucleonic degrees of freedom (especially quarks) than classical probes

TWO-PHOTON PHYSICS IN NUCLEUS-NUCLEUS COLLISIONS AT RHIC

International Nuclear Information System (INIS)

Nystrand, J.; Klein, S.

1998-01-01

Ultra-relativistic heavy-ions carry strong electromagnetic and nuclear fields. Interactions between these fields in peripheral nucleus-nucleus collisions can probe many interesting physics topics. This presentation will focus on coherent two-photon and photonuclear processes at RHIC. The rates for these interactions will be high. The coherent coupling of all the protons in the nucleus enhances the equivalent photon flux by a factor Z 2 up to an energy of ∼ 3 GeV. The plans for studying coherent interactions with the STAR experiment will be discussed. Experimental techniques for separating signal from background will be presented

Two-photon physics in nucleus-nucleus collisions at RHIC

International Nuclear Information System (INIS)

Nystrand, J.; Klein, S.

1998-01-01

Ultra-relativistic heavy-ions carry strong electromagnetic and nuclear fields. Interactions between these fields in peripheral nucleus-nucleus collisions can probe many interesting physics topics. This presentation will focus on coherent two-photon and photonuclear processes at RHIC. The rates for these interactions will be high. The coherent coupling of all the protons in the nucleus enhances the equivalent photon flux by a factor Z 2 up to an energy of ∼ 3 GeV. The plans for studying coherent interactions with the STAR experiment will be discussed. Experimental techniques for separating signal from background will be presented

Functionalized active-nucleus complex sensor

Science.gov (United States)

Pines, Alexander; Wemmer, David E.; Spence, Megan; Rubin, Seth

2003-11-25

A functionalized active-nucleus complex sensor that selectively associates with one or more target species, and a method for assaying and screening for one or a plurality of target species utilizing one or a plurality of functionalized active-nucleus complexes with at least two of the functionalized active-nucleus complexes having an attraction affinity to different corresponding target species. The functionalized active-nucleus complex has an active-nucleus and a targeting carrier. The method involves functionalizing an active-nucleus, for each functionalized active-nucleus complex, by incorporating the active-nucleus into a macromolucular or molecular complex that is capable of binding one of the target species and then bringing the macromolecular or molecular complexes into contact with the target species and detecting the occurrence of or change in a nuclear magnetic resonance signal from each of the active-nuclei in each of the functionalized active-nucleus complexes.

The nucleon-nucleus scattering at intermediate energies

International Nuclear Information System (INIS)

Auger, J.-P.

1976-01-01

The Glauber model has the merit to connect directly the nucleon-nucleus elastic differential cross section with the nucleon-nucleon amplitude and nuclear densities. The general agreement between the 1 GeV proton elastic scattering differential cross sections calculated without adjustable parameter and the experimental data (from He 4 to Pb 208 ) is rather satisfactory up to 2. - 2.5 fm -1 momentum transfer. Although the 1 GeV proton elastic scattering experiments constitute at present one of the best method in determining neutron densities, it seems that self-consistent calculations bring the best knowledge of these densities. The model independent analysis performed with electron and proton scattering experiments show that the difference between neutron and proton r.m.s. radius cannot be determined better than 25-30% for Pb 208 [fr

Strangeness production in hadron-hadron, hadron-nucleus, and nucleus-nucleus collisions in the dual parton model

International Nuclear Information System (INIS)

Moehring, H.; Ranft, J.; Capella, A.; Tran Thanh Van, J.

1993-01-01

Λ, bar Λ, and K S 0 production is studied in a Monte Carlo dual parton model for hadron-hadron, hadron-nucleus, and nucleus-nucleus collisions with an SU(3) symmetric sea for chain formation (chain ends) but strangeness suppression in the chain fragmentation process. Additionally, (qq)-(bar q bar q) production from the sea was introduced into the chain formation process with the same probability as for the q→qq branching within the chain decay process. With these assumptions, multiplicity ratios and Feynman-x distributions for strange particles in h-h and multiplicity ratios in heavy ion collisions are reasonably well reproduced

The nuclear response and the imaginary potential for nucleus-nucleus collisions

International Nuclear Information System (INIS)

Phatak, S.C.; Sinha, B.

1983-01-01

The Fermi-gas model is used in this paper to study the nucleus-nucleus collision. The field produced by one of the nuclei is considered to act on nucleons in the other nucleus, which is treated as a Fermi gas of radius R. The imaginary part of the (non-local) nucleus-nucleus potential is then computed by evaluating the energy-conserving second-order term in which the intermediate states are particle-hole excitations produced in the Fermi gas. The equivalent local potential, obtained by using the Perey-Saxon method, is compared with phenomenological imaginary potentials. Later it is shown that, in the limit of small range of non-locality, the imaginary potential can be related to the nuclear response function. With this, one can write the nuclear friction coefficient that is used in phenomenological analyses of heavy-ion collisions in terms of the imaginary potential. (orig.)

Secondhand tobacco smoke exposure differentially alters nucleus tractus solitarius neurons at two different ages in developing non-human primates

International Nuclear Information System (INIS)

Sekizawa, Shin-ichi; Joad, Jesse P.; Pinkerton, Kent E.; Bonham, Ann C.

2010-01-01

Exposing children to secondhand tobacco smoke (SHS) is associated with increased risk for asthma, bronchiolitis and SIDS. The role for changes in the developing CNS contributing to these problems has not been fully explored. We used rhesus macaques to test the hypothesis that SHS exposure during development triggers neuroplastic changes in the nucleus tractus solitarius (NTS), where lung sensory information related to changes in airway and lung function is first integrated. Pregnant monkeys were exposed to filtered air (FA) or SHS for 6 h/day, 5 days/week starting at 50-day gestational age. Mother/infant pairs continued the exposures postnatally to age 3 or 13 months, which may be equivalent to approximately 1 or 4 years of human age, respectively. Whole-cell recordings were made of second-order NTS neurons in transverse brainstem slices. To target the consequences of SHS exposure based on neuronal subgroups, we classified NTS neurons into two phenotypes, rapid-onset spiking (RS) and delayed-onset spiking (DS), and then evaluated intrinsic and synaptic excitabilities in FA-exposed animals. RS neurons showed greater cell excitability especially at age of 3 months while DS neurons received greater amplitudes of excitatory postsynaptic currents (EPSCs). Developmental neuroplasticity such as increases in intrinsic and synaptic excitabilities were detected especially in DS neurons. In 3 month olds, SHS exposure effects were limited to excitatory changes in RS neurons, specifically increases in evoked EPSC amplitudes and increased spiking responses accompanied by shortened action potential width. By 13 months, the continued SHS exposure inhibited DS neuronal activity; decreases in evoked EPSC amplitudes and blunted spiking responses accompanied by prolonged action potential width. The influence of SHS exposure on age-related and phenotype specific changes may be associated with age-specific respiratory problems, for which SHS exposure can increase the risk, such as SIDS

Dihydroartemisinin inhibits the human erythroid cell differentiation by altering the cell cycle

International Nuclear Information System (INIS)

Finaurini, Sara; Basilico, Nicoletta; Corbett, Yolanda; D’Alessandro, Sarah; Parapini, Silvia; Olliaro, Piero; Haynes, Richard K.; Taramelli, Donatella

2012-01-01

Artemisinin derivatives such as dihydroartemisinin (DHA) induce significant depletion of early embryonic erythroblasts in animal models. We have reported previously that DHA specifically targets pro-erythroblasts and basophilic erythroblasts, when human CD34+ stem cells are differentiated toward the erythroid lineage, indicating that a window of susceptibility to artemisinins may exist also in human developmental erythropoiesis during pregnancy. To better investigate the toxicity of artemisinin derivatives, the structure–activity relationship was evaluated against the K562 leukaemia cell line, used as a model for differentiating early human erythroblasts. All artemisinins derivatives, except deoxyartemisinin, inhibited both spontaneous and induced erythroid differentiation, confirming that the peroxide bridge is responsible for the erythro-toxicity. On the contrary, cell growth was markedly reduced by DHA, artemisone and artesunate but not by artemisinin, 10-deoxoartemisinin or deoxy-artemisinin. The substituent at position C-10 is responsible only for the anti-proliferative effect, since 10-deoxoartemisinin did not reduce cell growth but arrested the differentiation of K562 cells. In particular, the results showed that DHA resulted the most potent and rapidly acting compound of the drug family, causing (i) the decreased expression of GpA surface receptors and the down regulation the γ-globin gene; (ii) the alteration of S phase of cell cycle and (iii) the induction of programmed cell death of early erythroblasts in a dose dependent manner within 24 h. In conclusion, these findings confirm that the active metabolite DHA is responsible for the erythro-toxicity of most of artemisinins used in therapy. Thus, as long as no further clinical data are available, current WHO recommendations of avoiding malaria treatment with artemisinins during the first trimester of pregnancy remain valid.

Field theoretical approach to proton-nucleus reactions. I - One step inelastic scattering

International Nuclear Information System (INIS)

Eiras, A.; Kodama, T.; Nemes, M.C.

1988-01-01

In this work we obtain a closed form expression to the double differential cross section for one step proton-nucleus reaction within a field theoretical framework. Energy and momentum conservation as well as nuclear structure effects are consistently taken into account within the field theoretical eikonal approximation. In our formulation the kinematics of such reaction is not dominated by the free nucleon-nucleon cross section but a new factor which we call relativistic differential cross section in a Born Approximation. (author) [pt

Differential Involvement of the Suprachiasmatic Nucleus in Lipopolysaccharide-Induced Plasma Glucose and Corticosterone Responses

NARCIS (Netherlands)

Kalsbeek, Andries; Liu, Ji; Lei, Jun; Timmermans, Loes; Foppen, Ewout; Cailotto, Cathy; Fliers, Eric

2012-01-01

The hypothalamic suprachiasmatic nucleus (SCN) is an essential component of the circadian timing system, and an important determinant of neuroendocrine and metabolic regulation. Recent data indicate a modulatory role for the immune system on the circadian timing system. The authors investigated how

Methionine restriction alters bone morphology and affects osteoblast differentiation

Directory of Open Access Journals (Sweden)

Amadou Ouattara

2016-12-01

Full Text Available Methionine restriction (MR extends the lifespan of a wide variety of species, including rodents, drosophila, nematodes, and yeasts. MR has also been demonstrated to affect the overall growth of mice and rats. The objective of this study was to evaluate the effect of MR on bone structure in young and aged male and female C57BL/6J mice. This study indicated that MR affected the growth rates of males and young females, but not aged females. MR reduced volumetric bone mass density (vBMD and bone mineral content (BMC, while bone microarchitecture parameters were decreased in males and young females, but not in aged females compared to control-fed (CF mice. However, when adjusted for bodyweight, the effect of MR in reducing vBMD, BMC and microarchitecture measurements was either attenuated or reversed suggesting that the smaller bones in MR mice is appropriate for its body size. In addition, CF and MR mice had similar intrinsic strength properties as measured by nanoindentation. Plasma biomarkers suggested that the low bone mass in MR mice could be due to increased collagen degradation, which may be influenced by leptin, IGF-1, adiponectin and FGF21 hormone levels. Mouse preosteoblast cell line cultured under low sulfur amino acid growth media attenuated gene expression levels of Col1al, Runx2, Bglap, Alpl and Spp1 suggesting delayed collagen formation and bone differentiation. Collectively, our studies revealed that MR altered bone morphology which could be mediated by delays in osteoblast differentiation. Keywords: Methionine restriction, Aged mice, Micro-computed tomography, Nanoindentation, MC3T3-E1 subclone 4

Nucleus-nucleus interaction constants at energies of 0.1-1.0 GeV/nucleon

International Nuclear Information System (INIS)

Dudkin, V.E.; P'yanov, I.I.; Stepnov, V.D.

1979-01-01

A method for calculating nucleus-nuclear reactions being a further development of the cascade model is proposed. The nucleus-nucleus interaction is represented as a superposition of a series of synchronous cascades initiated by nucleous and α-clusters getting into the nuclei overlapping region. Determination of an interaction partner and calculation of an elementary nucleon and α-cluster collision act are carried out using the same method as for calculation of the nucleon-nuclear cascade. Inelastic channels are not considered. The cross section values of cascade particle interaction, as well as of free particle interaction are given from the published literature. The experiment for verification of the calculation method is carried out. An emulsion chamber of the 0.3 l volume has been exposed at the 35 km height in the vicinity of the 64 deg nothern latitude during 8.5 hr. 223 disintegrations of nuclear emulsion by cosmic radiation nuclei at the 0.1-1.0 GeV/nucleon energy and the >2 charge are investigated. 147 interactions on photoemulsion light nuclei are singled out from these disintegrations. The average multiplicity of all the charged pions is 0.22+-0.05 for light and 0.44+-0.09 for heavy photoemulsion nuclei. The calculation is carried out for nitrogen nuclei interaction at the 0.35 GeV/nucleon energy. Parametric analysis of the calculation method has shown that the clusterization coefficients and the nuclear parameter effect secondary particle multiplicity (SPM) and weakly influence on their energy and angular distributions. The nuclear parameter change from 1.1 to 1.6 F decreases average SPM in different energy ranges down to 25-40%. The comparison of the calculation data with the experimental one obtained in the given paper and other ones, shows satisfactory agreement both for differential and average characteristics of secondary charged particles

Changes in Appetitive Associative Strength Modulates Nucleus Accumbens, But Not Orbitofrontal Cortex Neuronal Ensemble Excitability.

Science.gov (United States)

Ziminski, Joseph J; Hessler, Sabine; Margetts-Smith, Gabriella; Sieburg, Meike C; Crombag, Hans S; Koya, Eisuke

2017-03-22

Cues that predict the availability of food rewards influence motivational states and elicit food-seeking behaviors. If a cue no longer predicts food availability, then animals may adapt accordingly by inhibiting food-seeking responses. Sparsely activated sets of neurons, coined "neuronal ensembles," have been shown to encode the strength of reward-cue associations. Although alterations in intrinsic excitability have been shown to underlie many learning and memory processes, little is known about these properties specifically on cue-activated neuronal ensembles. We examined the activation patterns of cue-activated orbitofrontal cortex (OFC) and nucleus accumbens (NAc) shell ensembles using wild-type and Fos-GFP mice, which express green fluorescent protein (GFP) in activated neurons, after appetitive conditioning with sucrose and extinction learning. We also investigated the neuronal excitability of recently activated, GFP+ neurons in these brain areas using whole-cell electrophysiology in brain slices. Exposure to a sucrose cue elicited activation of neurons in both the NAc shell and OFC. In the NAc shell, but not the OFC, these activated GFP+ neurons were more excitable than surrounding GFP- neurons. After extinction, the number of neurons activated in both areas was reduced and activated ensembles in neither area exhibited altered excitability. These data suggest that learning-induced alterations in the intrinsic excitability of neuronal ensembles is regulated dynamically across different brain areas. Furthermore, we show that changes in associative strength modulate the excitability profile of activated ensembles in the NAc shell. SIGNIFICANCE STATEMENT Sparsely distributed sets of neurons called "neuronal ensembles" encode learned associations about food and cues predictive of its availability. Widespread changes in neuronal excitability have been observed in limbic brain areas after associative learning, but little is known about the excitability changes that

Emergence of nuclear heparanase induces differentiation of human mammary cancer cells

International Nuclear Information System (INIS)

Nobuhisa, Tetsuji; Naomoto, Yoshio; Takaoka, Munenori; Tabuchi, Yoko; Ookawa, Keizou; Kitamoto, Dai; Gunduz, Esra; Gunduz, Mehmet; Nagatsuka, Hitoshi; Haisa, Minoru; Matsuoka, Junji; Nakajima, Motowo; Tanaka, Noriaki

2005-01-01

The study of epithelial differentiation touches upon many modern aspects of biology. The epithelium is in constant dialogue with the underlying mesenchyme to control stem cell activity, proliferation in transit-amplifying compartments, lineage commitment, terminal differentiation and, ultimately, cell death. There are spatially distinct compartments dedicated to each of these events. Recently we reported that heparanase is expressed in nucleus as well as in the cytoplasm and that nuclear heparanase seems to be related to cell differentiation. In this study, we investigated the role of nuclear heparanase in differentiation by transducing human mammary epithelial cancer cells with heparanase which was delivered specifically into nucleus. We observed that expression of nuclear heparanase allowed the cells to differentiate with the appearance of lipid droplets. This finding supports the idea that heparanase plays a novel role in epithelial cell differentiation apart from its known enzymatic function

Effective nucleus-nucleus potentials derived from the generator coordinate method

Energy Technology Data Exchange (ETDEWEB)

Friedrich, H; Canto, L F [Oxford Univ. (UK). Dept. of Theoretical Physics

1977-11-07

The equivalence of the generator coordinate method (GCM) and the resonating group method (RGM) and the formal equivalence of the RGM and the orthogonality condition model (OCM) lead to a relation connecting the effective nucleus-nucleus potentials of the OCM with matrix elements of the GCM. This relation may be used to derive effective nucleus-nucleus potentials directly from GCM matrix elements without explicit reference to the potentials of the RGM. In a first application local and l-independent effective potentials are derived from diagonal GCM matrix elements which represent the energy surfaces of a two-centre shell model. Using these potentials the OCM can reproduce the results of a full RGM calculation very well for the elastic scattering of two ..cap alpha..-particles and fairly well for elastic /sup 16/O-/sup 16/O scattering.

Experimental search for compression phenomena in fast nucleus--nucleus collisions

International Nuclear Information System (INIS)

Schopper, E.; Baumgardt, H.G.; Obst, E.

1977-01-01

The occurrence of compression phenomena and shock waves, connected with the increase of the density of the nuclear matter during the interpenetration of two fast nuclei, are discussed. Current experiments dealing with this problem are reviewed. Before considering the mechanism of the interpenetration of two fast nuclei it may be useful to look at more simple situations, i.e., proton-proton interactions, then to envelop them with nuclear matter, considering proton-nucleus interactions. Only very general features are described, which may give suggestions for the understanding of the nucleus-nucleus impact

The mechanism of nuclear energy release in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Strugalski, Z.; Strugalska-Gola, E.

1998-01-01

The mechanism of intranuclear energy release in reactions induced by nucleus-nucleus collisions at energies higher than ∼ 0.5 GeV/nucl. is presented - as prompted experimentally. The intranuclear energy release goes through local damages of the colliding nuclei

Robust Nucleus/Cell Detection and Segmentation in Digital Pathology and Microscopy Images: A Comprehensive Review.

Science.gov (United States)

Xing, Fuyong; Yang, Lin

2016-01-01

Digital pathology and microscopy image analysis is widely used for comprehensive studies of cell morphology or tissue structure. Manual assessment is labor intensive and prone to interobserver variations. Computer-aided methods, which can significantly improve the objectivity and reproducibility, have attracted a great deal of interest in recent literature. Among the pipeline of building a computer-aided diagnosis system, nucleus or cell detection and segmentation play a very important role to describe the molecular morphological information. In the past few decades, many efforts have been devoted to automated nucleus/cell detection and segmentation. In this review, we provide a comprehensive summary of the recent state-of-the-art nucleus/cell segmentation approaches on different types of microscopy images including bright-field, phase-contrast, differential interference contrast, fluorescence, and electron microscopies. In addition, we discuss the challenges for the current methods and the potential future work of nucleus/cell detection and segmentation.

The correlation between the transverse polarization and transverse momentum of lambda produced in relativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Ye Yunxiu; Zhou Xin; Ji Gang; Su Shufang; Zhu Guohuai

1996-01-01

The transverse polarization of lambda produced in relativistic nucleus-nucleus collisions is determined. The effect from the interaction between spin moment and magnetic field is corrected. The near zero transverse polarization and non-correlation between transverse polarization and transverse momentum are obtained and compared to ones obtained from the nucleus-nucleus interactions at lower energies. This comparison shows that the production mechanism of lambdas in the relativistic nucleus-nucleus collisions is different from one in the nucleus-nucleus reactions at lower energies

Nucleus-nucleus interactions in the transition energy regime

International Nuclear Information System (INIS)

Volant, C.

1985-02-01

There are at least two ways for studying large interactions in nucleus-nucleus collisions. One way is to use the method of angular correlations between fission fragments. The aim of the experiments presented here was to make a survey on the role of the various experimental parameters. In that respect three targets have been studied and different projectiles and bombarding energies have been used. Results are presented and discussed

Chromatin and lamin A determine two different mechanical response regimes of the cell nucleus.

Science.gov (United States)

Stephens, Andrew D; Banigan, Edward J; Adam, Stephen A; Goldman, Robert D; Marko, John F

2017-07-07

The cell nucleus must continually resist and respond to intercellular and intracellular mechanical forces to transduce mechanical signals and maintain proper genome organization and expression. Altered nuclear mechanics is associated with many human diseases, including heart disease, progeria, and cancer. Chromatin and nuclear envelope A-type lamin proteins are known to be key nuclear mechanical components perturbed in these diseases, but their distinct mechanical contributions are not known. Here we directly establish the separate roles of chromatin and lamin A/C and show that they determine two distinct mechanical regimes via micromanipulation of single isolated nuclei. Chromatin governs response to small extensions (<3 μm), and euchromatin/heterochromatin levels modulate the stiffness. In contrast, lamin A/C levels control nuclear strain stiffening at large extensions. These results can be understood through simulations of a polymeric shell and cross-linked polymer interior. Our results provide a framework for understanding the differential effects of chromatin and lamin A/C in cell nuclear mechanics and their alterations in disease. © 2017 Stephens et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication 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).

Alteration of circadian rhythm during epileptogenesis: implications for the suprachiasmatic nucleus circuits.

Science.gov (United States)

Xiang, Yan; Li, Zhi-Xiao; Zhang, Ding-Yu; He, Zhi-Gang; Hu, Ji; Xiang, Hong-Bing

2017-01-01

It is important to realize that characterization of the circadian rhythm patterns of seizure occurrence can implicate in diagnosis and treatment of selected types of epilepsy. Evidence suggests a role for the suprachiasmatic nucleus (SCN) circuits in overall circadian rhythm and seizure susceptibility both in animals and humans. Thus, we conclude that SCN circuits may exert modifying effects on circadian rhythmicity and neuronal excitability during epileptogenesis. SCN circuits will be studied in our brain centre and collaborating centres to explore further the interaction between the circadian rhythm and epileptic seizures. More and thorough research is warranted to provide insight into epileptic seizures with circadian disruption comorbidities such as disorders of cardiovascular parameters and core body temperature circadian rhythms.

The application of a phenomenological model to inelastic nucleus-nucleus interactions for laboratory momenta below 5 GeV/c per nucleon of the incident nucleus

International Nuclear Information System (INIS)

Grishin, V.G.; Kladnitskaya, E.N.

1985-01-01

A phenomenological model for inelastic nucleus-nucleus interactions at momenta below 5 GeV/c per nucleon is described. Particle interactions inside the interacting nuclei are described by phenomenological models of hadron-nucleus and hadron-nucleon interactions. The Monte-Carlo model provides the kinematic variables for a set of events under study. The comparison of the model inclusive distri-- butions for different particles and nucleus-nucleus interactions agrees well with the experimental data

Nucleus Ruber of Actinopterygians.

Science.gov (United States)

Nakayama, Tomoya; Miyajima, Satoshi; Nishino, Hirotaka; Narita, Junya; Abe, Hideki; Yamamoto, Naoyuki

2016-01-01

Nucleus ruber is known as an important supraspinal center that controls forelimb movements in tetrapods, and the rubral homologue may serve similar functions in fishes (motor control of pectoral fin). However, two apparently different structures have been identified as 'nucleus ruber' in actinopterygians. One is nucleus ruber of Goldstein (1905) (NRg), and the other nucleus ruber of Nieuwenhuys and Pouwels (1983) (NRnp). It remains unclear whether one of these nuclei (or perhaps both) is homologous to tetrapod nucleus ruber. To resolve this issue from a phylogenetic point of view, we have investigated the distribution of tegmental neurons retrogradely labeled from the spinal cord in eight actinopterygian species. We also investigated the presence/absence of the two nuclei with Nissl- or Bodian-stained brain section series of an additional 28 actinopterygian species by comparing the morphological features of candidate rubral neurons with those of neurons revealed by the tracer studies. Based on these analyses, the NRg was identified in all actinopterygians investigated in the present study, while the NRnp appears to be absent in basal actinopterygians. The phylogenetic distribution pattern indicates that the NRg is the more likely homologue of nucleus ruber, and the NRnp may be a derived nucleus that emerged during the course of actinopterygian evolution. © 2016 S. Karger AG, Basel.

Raclopride or high-frequency stimulation of the subthalamic nucleus stops cocaine-induced motor stereotypy and restores related alterations in prefrontal basal ganglia circuits.

Science.gov (United States)

Aliane, Verena; Pérez, Sylvie; Deniau, Jean-Michel; Kemel, Marie-Louise

2012-11-01

Motor stereotypy is a key symptom of various neurological or neuropsychiatric disorders. Neuroleptics or the promising treatment using deep brain stimulation stops stereotypies but the mechanisms underlying their actions are unclear. In rat, motor stereotypies are linked to an imbalance between prefrontal and sensorimotor cortico-basal ganglia circuits. Indeed, cortico-nigral transmission was reduced in the prefrontal but not sensorimotor basal ganglia circuits and dopamine and acetylcholine release was altered in the prefrontal but not sensorimotor territory of the dorsal striatum. Furthermore, cholinergic transmission in the prefrontal territory of the dorsal striatum plays a crucial role in the arrest of motor stereotypy. Here we found that, as previously observed for raclopride, high-frequency stimulation of the subthalamic nucleus (HFS STN) rapidly stopped cocaine-induced motor stereotypies in rat. Importantly, raclopride and HFS STN exerted a strong effect on cocaine-induced alterations in prefrontal basal ganglia circuits. Raclopride restored the cholinergic transmission in the prefrontal territory of the dorsal striatum and the cortico-nigral information transmissions in the prefrontal basal ganglia circuits. HFS STN also restored the N-methyl-d-aspartic-acid-evoked release of acetylcholine and dopamine in the prefrontal territory of the dorsal striatum. However, in contrast to raclopride, HFS STN did not restore the cortico-substantia nigra pars reticulata transmissions but exerted strong inhibitory and excitatory effects on neuronal activity in the prefrontal subdivision of the substantia nigra pars reticulata. Thus, both raclopride and HFS STN stop cocaine-induced motor stereotypy, but exert different effects on the related alterations in the prefrontal basal ganglia circuits. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

Description of inelastic nucleus-nucleus interactions at medium energy using dual parton model

International Nuclear Information System (INIS)

Polanski, A.; Shmakov, S.Yu.; Uzhinskij, V.V.

1989-01-01

It is shown that the dual parton model taking into account the processes of diffraction dissociation to the low mass states and finite energy corrections to the asymptotic Abramovski-Gribov-Kancheli cutting rules allows satisfactory description of existing experimental data on hadron-nucleus and nucleus-nucleus interactions at medium energy. (orig.)

Beyond cytoarchitectonics: the internal and external connectivity structure of the caudate nucleus.

Directory of Open Access Journals (Sweden)

Sonja A Kotz

Full Text Available While there is ample evidence on the functional and connectional differentiation of the caudate nucleus (CN, less is known about its potential microstructural subdivisions. However, this latter aspect is critical to the local information processing capabilities of the tissue. We applied diffusion MRI, a non-invasive in vivo method that has great potential for the exploration of the brain structure-behavior relationship, in order to characterize the local fiber structure in gray matter of the CN. We report novel evidence of a functionally meaningful structural tri-partition along the anterior-posterior axis of this region. The connectivity of the CN subregions is in line with connectivity evidence from earlier invasive studies in animal models. In addition, histological validation using polarized light imaging (PLI confirms these results, corroborating the notion that cortico-subcortico-cortical loops involve microstructurally differentiated regions in the caudate nucleus. Methodologically speaking, the comparison with advanced analysis of diffusion MRI shows that diffusion tensor imaging (DTI yields a simplified view of the CN fiber architecture which is refined by advanced high angular resolution imaging methods.

Robust Nucleus/Cell Detection and Segmentation in Digital Pathology and Microscopy Images: A Comprehensive Review

Science.gov (United States)

Xing, Fuyong; Yang, Lin

2016-01-01

Digital pathology and microscopy image analysis is widely used for comprehensive studies of cell morphology or tissue structure. Manual assessment is labor intensive and prone to inter-observer variations. Computer-aided methods, which can significantly improve the objectivity and reproducibility, have attracted a great deal of interest in recent literatures. Among the pipeline of building a computer-aided diagnosis system, nucleus or cell detection and segmentation play a very important role to describe the molecular morphological information. In the past few decades, many efforts have been devoted to automated nucleus/cell detection and segmentation. In this review, we provide a comprehensive summary of the recent state-of-the-art nucleus/cell segmentation approaches on different types of microscopy images including bright-field, phase-contrast, differential interference contrast (DIC), fluorescence, and electron microscopies. In addition, we discuss the challenges for the current methods and the potential future work of nucleus/cell detection and segmentation. PMID:26742143

Signaling from the secretory granule to the nucleus: Uhmk1 and PAM.

Science.gov (United States)

Francone, Victor P; Ifrim, Marius F; Rajagopal, Chitra; Leddy, Christopher J; Wang, Yanping; Carson, John H; Mains, Richard E; Eipper, Betty A

2010-08-01

Neurons and endocrine cells package peptides in secretory granules (large dense-core vesicles) for storage and stimulated release. Studies of peptidylglycine alpha-amidating monooxygenase (PAM), an essential secretory granule membrane enzyme, revealed a pathway that can relay information from secretory granules to the nucleus, resulting in alterations in gene expression. The cytosolic domain (CD) of PAM, a type 1 membrane enzyme essential for the production of amidated peptides, is basally phosphorylated by U2AF homology motif kinase 1 (Uhmk1) and other Ser/Thr kinases. Proopiomelanocortin processing in AtT-20 corticotrope tumor cells was increased when Uhmk1 expression was reduced. Uhmk1 was concentrated in the nucleus, but cycled rapidly between nucleus and cytosol. Endoproteolytic cleavage of PAM releases a soluble CD fragment that localizes to the nucleus. Localization of PAM-CD to the nucleus was decreased when PAM-CD with phosphomimetic mutations was examined and when active Uhmk1 was simultaneously overexpressed. Membrane-tethering Uhmk1 did not eliminate its ability to exclude PAM-CD from the nucleus, suggesting that cytosolic Uhmk1 could cause this response. Microarray analysis demonstrated the ability of PAM to increase expression of a small subset of genes, including aquaporin 1 (Aqp1) in AtT-20 cells. Aqp1 mRNA levels were higher in wild-type mice than in mice heterozygous for PAM, indicating that a similar relationship occurs in vivo. Expression of PAM-CD also increased Aqp1 levels whereas expression of Uhmk1 diminished Aqp1 expression. The outlines of a pathway that ties secretory granule metabolism to the transcriptome are thus apparent.

Dimuon enhancement in nucleus-nucleus ultrarelativistic interactions

International Nuclear Information System (INIS)

Bordalo, Paula; Abreu, M.C.; Alessandro, B.; Alexa, C.; Arnaldi, R.; Astruc, J.; Atayan, M.; Baglin, C.; Baldit, A.; Bedjidian, M.; Bellaiche, F.; Beole, S.; Bohrani, A.; Boldea, V.; Bussiere, A.; Capelli, L.; Caponi, V.; Casagrande, L.; Castor, J.; Chambon, T.; Chaurand, B.; Chevrot, I.; Cheynis, B.; Chiavassa, E.; Cicalo, C.; Comets, M.P.; Constans, N.; Constantinescu, S.; Contardo, D.; Cruz, J.; De Falco, A.; De Marco, N.; Dellacasa, G.; Devaux, A.; Dita, S.; Drapier, O.; Ducroux, L.; Espagnon, B.; Fargeix, J.; Ferreira, R.; Filippov, S.N.; Fleuret, F.; Force, P.; Gallio, M.; Gavrilov, Y.K.; Gerschel, C.; Giubellino, P.; Golubeva, M.B.; Gonin, M.; Gorodetzky, P.; Grigorian, A.A.; Grossiord, J.Y.; Guber, F.F.; Guichard, A.; Gulkanyan, H.; Hakobyan, R.; Haroutunian, R.; Idzik, M.; Jouan, D.; Karavitcheva, T.L.; Kluberg, L.; Kossakowski, R.; Kurepin, A.B.; Landau, G.; Le Bornec, Y.; Lourenco, C.; Luquin, L.; Macciotta, P.; Mac Cormick, M.; Mandry, R.; Marzari-Chiesa, A.; Masera, M.; Masoni, A.; Mehrabyan, S.; Monteno, M.; Mourgues, S.; Musso, A.; Ohlsson-Malek, F.; Petiau, P.; Piccotti, A.; Pizzi, J.R.; Prado da Silva, W.L.; Puddu, G.; Quintans, C.; Racca, C.; Ramello, L.; Ramos, S.; Rato-Mendes, P.; Riccati, L.; Romana, A.; Ropotar, I.; Saturnini, P.; Scomparin, E.; Serci, S.; Shahoyan, R.; Silva, S.; Sitta, M.; Soave, C.; Sonderegger, P.; Tarrago, X.; Topilskaya, N.S.; Usai, G.L.; Varela, J.; Vercellin, E.; Villatte, L.

1999-01-01

The study of muon pairs in the mass region 1.5 μμ 2 in 450 GeV/c p-A, 200 GeV/nucleon S-U and 158 GeV/nucleon Pb-Pb collisions is presented. In p-A interactions, the dimuon signal mass spectra are well described by a superposition of Drell-Yan and charmed meson semi-leptonic decay contributions, in agreement with previous experiments when considering a linear A dependence. In nucleus-nucleus reactions, taking only into account these two physical ingredients, a dimuon enhancement both with increasing A·B and centrality is observed

Physical meaning of the yields from hadron-nucleon, hadron-nucleus, and nucleus-nucleus collisions observed in experiments

International Nuclear Information System (INIS)

Strugalski, Z.

1995-01-01

A physical meaning of the outcomes from hadronic and nuclear collision processes at high energies is presented, as prompted experimentally. The fast and slow stages in hadron-nucleus collisions are distinguished. Hadrons are produced via intermediate objects observed in hadron-nucleus collisions. The intermediate objects may be treated as the groups of quarks or the quark bags. 37 refs

Influence of Porcine Intervertebral Disc Matrix on Stem Cell Differentiation

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Hans-Lothar Fuchsbauer

2011-08-01

Full Text Available For back disorders, cell therapy is one approach for a real regeneration of a degenerated nucleus pulposus. Human mesenchymal stem cells (hMSC could be differentiated into nucleus pulposus (NP-like cells and used for cell therapy. Therefore it is necessary to find a suitable biocompatible matrix, which supports differentiation. It could be shown that a differentiation of hMSC in a microbial transglutaminase cross-linked gelatin matrix is possible, but resulted in a more chondrocyte-like cell type. The addition of porcine NP extract to the gelatin matrix caused a differentiation closer to the desired NP cell phenotype. This concludes that a hydrogel containing NP extract without any other supplements could be suitable for differentiation of hMSCs into NP cells. The NP extract itself can be cross-linked by transglutaminase to build a hydrogel free of NP atypical substrates. As shown by side-specific biotinylation, the NP extract contains molecules with free glutamine and lysine residues available for the transglutaminase.

Meson-nucleus potentials and the search for meson-nucleus bound states

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Metag, V.; Nanova, M.; Paryev, E. Ya.

2017-11-01

Recent experiments studying the meson-nucleus interaction to extract meson-nucleus potentials are reviewed. The real part of the potentials quantifies whether the interaction is attractive or repulsive while the imaginary part describes the meson absorption in nuclei. The review is focused on mesons which are sufficiently long-lived to potentially form meson-nucleus quasi-bound states. The presentation is confined to meson production off nuclei in photon-, pion-, proton-, and light-ion induced reactions and heavy-ion collisions at energies near the production threshold. Tools to extract the potential parameters are presented. In most cases, the real part of the potential is determined by comparing measured meson momentum distributions or excitation functions with collision model or transport model calculations. The imaginary part is extracted from transparency ratio measurements. Results on K+ ,K0 ,K- , η ,η‧ , ω, and ϕ mesons are presented and compared with theoretical predictions. The interaction of K+ and K0 mesons with nuclei is found to be weakly repulsive, while the K- , η ,η‧ , ω and ϕ meson-nucleus potentials are attractive, however, with widely different strengths. Because of meson absorption in the nuclear medium the imaginary parts of the meson-nucleus potentials are all negative, again with a large spread. An outlook on planned experiments in the charm sector is given. In view of the determined potential parameters, the criteria and chances for experimentally observing meson-nucleus quasi-bound states are discussed. The most promising candidates appear to be the η and η‧ mesons.

Age-related changes in functional postsynaptic nicotinic acetylcholine receptor subunits in neurons of the laterodorsal tegmental nucleus, a nucleus important in drug addiction.

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Christensen, Mark H; Kohlmeier, Kristi A

2016-03-01

The earlier an individual initiates cigarette smoking, the higher the likelihood of development of dependency to nicotine, the addictive ingredient in cigarettes. One possible mechanism underlying this higher addiction liability is an ontogenetically differential cellular response induced by nicotine in neurons mediating the reinforcing or euphoric effects of this drug, which could arise from age-related differences in the composition of nicotinic acetylcholine receptor (nAChR) subunits. In the current study, we examined whether the subunit composition of nAChRs differed between neurons within the laterodorsal tegmentum (LDT), a nucleus importantly involved in drug addiction associated behaviours, across two periods of ontogeny in which nicotine-mediated excitatory responses were shown to depend on age. To this end, whole-cell patch-clamp recordings in mouse brain slices from identified LDT neurons, in combination with nAChR subunit-specific receptor antagonists, were conducted. Comparison of the contribution of different nAChR subunits to acetylcholine (ACh)-induced inward currents indicated that the contributions of the β2 and/or β4 and α7 nAChR subunits alter across age. Taken together, we conclude that across a limited ontogenetic period, there is plasticity in the subunit composition of nAChRs in LDT neurons. In addition, our data indicate, for the first time, functional presence of α6 nAChR subunits in LDT neurons within the age ranges studied. Changes in subunit composition of nAChRs across ontogeny could contribute to the age-related differential excitability induced by nicotine. Differences in the subunit composition of nAChRs within the LDT would be expected to contribute to ontogenetic-dependent outflow from the LDT to target regions, which include reward-related circuitry. © 2014 Society for the Study of Addiction.

Differential Rearing Alters Forced Swim Test Behavior, Fluoxetine Efficacy, and Post-Test Weight Gain in Male Rats

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Arndt, David L.; Peterson, Christy J.; Cain, Mary E.

2015-01-01

Environmental factors play a key role in the etiology of depression. The rodent forced swim test (FST) is commonly used as a preclinical model of depression, with increases in escape-directed behavior reflecting antidepressant effects, and increases in immobility reflecting behavioral despair. Environmental enrichment leads to serotonergic alterations in rats, but it is unknown whether these alterations may influence the efficacy of common antidepressants. Male Sprague-Dawley rats were reared in enriched (EC), standard (SC), or isolated (IC) conditions. Following the rearing period, fluoxetine (10 or 20 mg/kg, i.p.) was administered 23.5 hrs, 5 hrs, and 1 hr before locomotor and FST measures. Following locomotor testing and FST exposure, rats were weighed to assess fluoxetine-, FST-, and environmental condition-induced moderations in weight gain. Results revealed an antidepressant effect of environmental enrichment and a depressant effect of isolation. Regardless of significant fluoxetine effects on locomotor activity, fluoxetine generally decreased swimming and increased immobility in all three environmental conditions, with IC-fluoxetine (10 mg/kg) rats and EC-fluoxetine (20 mg/kg) rats swimming less than vehicle counterparts. Subchronic 20 mg/kg fluoxetine also induced significant weight loss, and differential rearing appeared to moderate weight gain following FST stress. These results suggest that differential rearing has the ability to alter FST behaviors, fluoxetine efficacy, and post-stressor well-being. Moreover, 20 mg/kg fluoxetine, administered subchronically, may lead to atypical effects of those commonly observed in the FST, highlighting the importance and impact of both environmental condition and dosing regimen in common animal models of depression. PMID:26154768

Differential Rearing Alters Forced Swim Test Behavior, Fluoxetine Efficacy, and Post-Test Weight Gain in Male Rats.

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David L Arndt

Full Text Available Environmental factors play a key role in the etiology of depression. The rodent forced swim test (FST is commonly used as a preclinical model of depression, with increases in escape-directed behavior reflecting antidepressant effects, and increases in immobility reflecting behavioral despair. Environmental enrichment leads to serotonergic alterations in rats, but it is unknown whether these alterations may influence the efficacy of common antidepressants. Male Sprague-Dawley rats were reared in enriched (EC, standard (SC, or isolated (IC conditions. Following the rearing period, fluoxetine (10 or 20 mg/kg, i.p. was administered 23.5 hrs, 5 hrs, and 1 hr before locomotor and FST measures. Following locomotor testing and FST exposure, rats were weighed to assess fluoxetine-, FST-, and environmental condition-induced moderations in weight gain. Results revealed an antidepressant effect of environmental enrichment and a depressant effect of isolation. Regardless of significant fluoxetine effects on locomotor activity, fluoxetine generally decreased swimming and increased immobility in all three environmental conditions, with IC-fluoxetine (10 mg/kg rats and EC-fluoxetine (20 mg/kg rats swimming less than vehicle counterparts. Subchronic 20 mg/kg fluoxetine also induced significant weight loss, and differential rearing appeared to moderate weight gain following FST stress. These results suggest that differential rearing has the ability to alter FST behaviors, fluoxetine efficacy, and post-stressor well-being. Moreover, 20 mg/kg fluoxetine, administered subchronically, may lead to atypical effects of those commonly observed in the FST, highlighting the importance and impact of both environmental condition and dosing regimen in common animal models of depression.

Differential Rearing Alters Forced Swim Test Behavior, Fluoxetine Efficacy, and Post-Test Weight Gain in Male Rats.

Science.gov (United States)

Arndt, David L; Peterson, Christy J; Cain, Mary E

2015-01-01

Environmental factors play a key role in the etiology of depression. The rodent forced swim test (FST) is commonly used as a preclinical model of depression, with increases in escape-directed behavior reflecting antidepressant effects, and increases in immobility reflecting behavioral despair. Environmental enrichment leads to serotonergic alterations in rats, but it is unknown whether these alterations may influence the efficacy of common antidepressants. Male Sprague-Dawley rats were reared in enriched (EC), standard (SC), or isolated (IC) conditions. Following the rearing period, fluoxetine (10 or 20 mg/kg, i.p.) was administered 23.5 hrs, 5 hrs, and 1 hr before locomotor and FST measures. Following locomotor testing and FST exposure, rats were weighed to assess fluoxetine-, FST-, and environmental condition-induced moderations in weight gain. Results revealed an antidepressant effect of environmental enrichment and a depressant effect of isolation. Regardless of significant fluoxetine effects on locomotor activity, fluoxetine generally decreased swimming and increased immobility in all three environmental conditions, with IC-fluoxetine (10 mg/kg) rats and EC-fluoxetine (20 mg/kg) rats swimming less than vehicle counterparts. Subchronic 20 mg/kg fluoxetine also induced significant weight loss, and differential rearing appeared to moderate weight gain following FST stress. These results suggest that differential rearing has the ability to alter FST behaviors, fluoxetine efficacy, and post-stressor well-being. Moreover, 20 mg/kg fluoxetine, administered subchronically, may lead to atypical effects of those commonly observed in the FST, highlighting the importance and impact of both environmental condition and dosing regimen in common animal models of depression.

Perfluorooctane sulfonate induces neuronal and oligodendrocytic differentiation in neural stem cells and alters the expression of PPARγ in vitro and in vivo

International Nuclear Information System (INIS)

Wan Ibrahim, Wan Norhamidah; Tofighi, Roshan; Onishchenko, Natalia; Rebellato, Paola; Bose, Raj; Uhlén, Per; Ceccatelli, Sandra

2013-01-01

Perfluorinated compounds are ubiquitous chemicals of major concern for their potential adverse effects on the human population. We have used primary rat embryonic neural stem cells (NSCs) to study the effects of perfluorooctane sulfonate (PFOS) on the process of NSC spontaneous differentiation. Upon removal of basic fibroblast growth factor, NSCs were exposed to nanomolar concentrations of PFOS for 48 h, and then allowed to differentiate for additional 5 days. Exposure to 25 or 50 nM concentration resulted in a lower number of proliferating cells and a higher number of neurite-bearing TuJ1-positive cells, indicating an increase in neuronal differentiation. Exposure to 50 nM also significantly increased the number of CNPase-positive cells, pointing to facilitation of oligodendrocytic differentiation. PPAR genes have been shown to be involved in PFOS toxicity. By q-PCR we detected an upregulation of PPARγ with no changes in PPARα or PPARδ genes. One of the downstream targets of PPARs, the mitochondrial uncoupling protein 2 (UCP2) was also upregulated. The number of TuJ1- and CNPase-positive cells increased after exposure to PPARγ agonist rosiglitazone (RGZ, 3 μM) and decreased after pre-incubation with the PPARγ antagonist GW9662 (5 μM). RGZ also upregulated the expression of PPARγ and UCP2 genes. Meanwhile GW9662 abolished the UCP2 upregulation and decreased Ca 2+ activity induced by PFOS. Interestingly, a significantly higher expression of PPARγ and UCP3 genes was also detected in mouse neonatal brain after prenatal exposure to PFOS. These data suggest that PPARγ plays a role in the alteration of spontaneous differentiation of NSCs induced by nanomolar concentrations of PFOS. - Highlights: • PFOS decreases proliferation of neural stem cells (NSCs). • PFOS induces neuronal and oligodendrocytic differentiation in NSCs. • PFOS alters expression of PPARγ and UCP2 in vitro. • PFOS alters expression of PPARγ and UCP3 in vivo. • Block of PPARγ by

Perfluorooctane sulfonate induces neuronal and oligodendrocytic differentiation in neural stem cells and alters the expression of PPARγ in vitro and in vivo

Energy Technology Data Exchange (ETDEWEB)

Wan Ibrahim, Wan Norhamidah, E-mail: hamidah@science.upm.edu.my [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden); Tofighi, Roshan, E-mail: Roshan.Tofighi@ki.se [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden); Onishchenko, Natalia, E-mail: Natalia.Onishchenko@ki.se [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden); Rebellato, Paola, E-mail: Paola.Rebellato@ki.se [Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-17177 Stockholm (Sweden); Bose, Raj, E-mail: Raj.Bose@ki.se [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden); Uhlén, Per, E-mail: Per.Uhlen@ki.se [Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-17177 Stockholm (Sweden); Ceccatelli, Sandra, E-mail: Sandra.Ceccatelli@ki.se [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden)

2013-05-15

Perfluorinated compounds are ubiquitous chemicals of major concern for their potential adverse effects on the human population. We have used primary rat embryonic neural stem cells (NSCs) to study the effects of perfluorooctane sulfonate (PFOS) on the process of NSC spontaneous differentiation. Upon removal of basic fibroblast growth factor, NSCs were exposed to nanomolar concentrations of PFOS for 48 h, and then allowed to differentiate for additional 5 days. Exposure to 25 or 50 nM concentration resulted in a lower number of proliferating cells and a higher number of neurite-bearing TuJ1-positive cells, indicating an increase in neuronal differentiation. Exposure to 50 nM also significantly increased the number of CNPase-positive cells, pointing to facilitation of oligodendrocytic differentiation. PPAR genes have been shown to be involved in PFOS toxicity. By q-PCR we detected an upregulation of PPARγ with no changes in PPARα or PPARδ genes. One of the downstream targets of PPARs, the mitochondrial uncoupling protein 2 (UCP2) was also upregulated. The number of TuJ1- and CNPase-positive cells increased after exposure to PPARγ agonist rosiglitazone (RGZ, 3 μM) and decreased after pre-incubation with the PPARγ antagonist GW9662 (5 μM). RGZ also upregulated the expression of PPARγ and UCP2 genes. Meanwhile GW9662 abolished the UCP2 upregulation and decreased Ca{sup 2+} activity induced by PFOS. Interestingly, a significantly higher expression of PPARγ and UCP3 genes was also detected in mouse neonatal brain after prenatal exposure to PFOS. These data suggest that PPARγ plays a role in the alteration of spontaneous differentiation of NSCs induced by nanomolar concentrations of PFOS. - Highlights: • PFOS decreases proliferation of neural stem cells (NSCs). • PFOS induces neuronal and oligodendrocytic differentiation in NSCs. • PFOS alters expression of PPARγ and UCP2 in vitro. • PFOS alters expression of PPARγ and UCP3 in vivo. • Block of PPAR�

Osmotic stress alters chromatin condensation and nucleocytoplasmic transport

Energy Technology Data Exchange (ETDEWEB)

Finan, John D.; Leddy, Holly A. [Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC (United States); Department of Biomedical Engineering, Duke University, Durham, NC (United States); Guilak, Farshid, E-mail: guilak@duke.edu [Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC (United States); Department of Biomedical Engineering, Duke University, Durham, NC (United States)

2011-05-06

Highlights: {yields} The rate of nucleocytoplasmic transport increases under hyper-osmotic stress. {yields} The mechanism is a change in nuclear geometry, not a change in permeability of the nuclear envelope. {yields} Intracytoplasmic but not intranuclear diffusion is sensitive to osmotic stress. {yields} Pores in the chromatin of the nucleus enlarge under hyper-osmotic stress. -- Abstract: Osmotic stress is a potent regulator of biological function in many cell types, but its mechanism of action is only partially understood. In this study, we examined whether changes in extracellular osmolality can alter chromatin condensation and the rate of nucleocytoplasmic transport, as potential mechanisms by which osmotic stress can act. Transport of 10 kDa dextran was measured both within and between the nucleus and the cytoplasm using two different photobleaching methods. A mathematical model was developed to describe fluorescence recovery via nucleocytoplasmic transport. As osmolality increased, the diffusion coefficient of dextran decreased in the cytoplasm, but not the nucleus. Hyper-osmotic stress decreased nuclear size and increased nuclear lacunarity, indicating that while the nucleus was getting smaller, the pores and channels interdigitating the chromatin had expanded. The rate of nucleocytoplasmic transport was increased under hyper-osmotic stress but was insensitive to hypo-osmotic stress, consistent with the nonlinear osmotic properties of the nucleus. The mechanism of this osmotic sensitivity appears to be a change in the size and geometry of the nucleus, resulting in a shorter effective diffusion distance for the nucleus. These results may explain physical mechanisms by which osmotic stress can influence intracellular signaling pathways that rely on nucleocytoplasmic transport.

The value of electroencephalography in differential diagnosis of altered mental status in emergency departments

International Nuclear Information System (INIS)

Duran, L.; Yardan, T.; Kati, C.; Akdemir, H. U.; Altuntas, M.; Balci, K.; Karadas, S.

2014-01-01

Objective: To evaluate the value of electroencephalography in patients with altered mental status in emergency departments. Methods: Demographical characteristics, types and aetiologies of seizures, and clinical outcomes of the patients were recorded. Patients were divided into 4 groups according to the complaints of admission: findings and symptoms of seizure; stroke and symptoms of stroke-related seizures; syncope; and metabolic abnormalities and other causes of altered mental status. The electroencephalography findings were classified into 3 groups: epileptiform discharges; paroxysmal electroencephalography abnormalities; and background slowing. Electroencephalography abnormalities in each subgroup were evaluated. SPSS 21 was used for statistical analysis. Results: Of the total 190 patients in the study, 117(61.6%) had pathological electroencephalography findings. The main reason for electroencephalography in the emergency department was the presence of seizure findings and symptoms in 98(51.6%) patients. The ratio of electroencephalography abnormality was higher in patients who were admitted with complaints of metabolic abnormality-related consciousness disturbances (p<0.001). A total of 124(65.3%) patients had neuroimagings. Electroencephalography abnormalities were found to be significantly higher in patients with neuroimagings compared to those without neuroimagings (p<0.003). Conclusion: Despite advanced neuroimaging techniques, electroencephalography is still an important tool in the differential diagnosis of altered mental status such as epileptic seizures, metabolic abnormalities, pseudo-seizures and syncope. (author)

Overexpression of suppressor of cytokine signaling 3 in the arcuate nucleus of juvenile Phodopus sungorus alters seasonal body weight changes.

Science.gov (United States)

Ganjam, Goutham K; Benzler, Jonas; Pinkenburg, Olaf; Boucsein, Alisa; Stöhr, Sigrid; Steger, Juliane; Culmsee, Carsten; Barrett, Perry; Tups, Alexander

2013-12-01

The profound seasonal cycle in body weight exhibited by the Djungarian hamster (Phodopus sungorus) is associated with the development of hypothalamic leptin resistance during long day photoperiod (LD, 16:8 h light dark cycle), when body weight is elevated relative to short day photoperiod (SD, 8:16 h light dark cycle). We previously have shown that this seasonal change in physiology is associated with higher levels of mRNA for the potent inhibitor of leptin signaling, suppressor of cytokine signaling-3 (SOCS3), in the arcuate nucleus (ARC) of LD hamsters relative to hamsters in SD. The alteration in SOCS3 gene expression preceded the body weight change suggesting that SOCS3 might be the molecular switch of seasonal body weight changes. To functionally characterize the role of SOCS3 in seasonal body weight regulation, we injected SOCS3 expressing recombinant adeno-associated virus type-2 (rAAV2-SOCS3) constructs into the ARC of leptin sensitive SD hamsters immediately after weaning. Hamsters that received rAAV2 expressing enhanced green fluorescent protein (rAAV2-EGFP) served as controls. ARC-directed SOCS3 overexpression led to a significant increase in body weight over a period of 12 weeks without fully restoring the LD phenotype. This increase was partially due to elevated brown and white adipose tissue mass. Gene expression of pro-opiomelanocortin was increased while thyroid hormone converting enzyme DIO3 mRNA levels were reduced in SD hamsters with SOCS3 overexpression. In conclusion, our data suggest that ARC-directed SOCS3 overexpression partially overcomes the profound seasonal body weight cycle exhibited by the hamster which is associated with altered pro-opiomelanocortin and DIO3 gene expression.

Proportion of collagen type II in the extracellular matrix promotes the differentiation of human adipose-derived mesenchymal stem cells into nucleus pulposus cells.

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Tao, Yiqing; Zhou, Xiaopeng; Liu, Dongyu; Li, Hao; Liang, Chengzhen; Li, Fangcai; Chen, Qixin

2016-01-01

During degeneration process, the catabolism of collagen type II and anabolism of collagen type I in nucleus pulposus (NP) may influence the bioactivity of transplanted cells. Human adipose-derived mesenchymal stem cells (hADMSCs) were cultured as a micromass or in a series of gradual proportion hydrogels of a mix of collagen types I and II. Cell proliferation and cytotoxicity were detected using CCK-8 and LDH assays respectively. The expression of differentiation-related genes and proteins, including SOX9, aggrecan, collagen type I, and collagen type II, was examined using RT-qPCR and Western blotting. Novel phenotypic genes were also detected by RT-qPCR and western blotting. Alcian blue and dimethylmethylene blue assays were used to investigate sulfate proteoglycan expression, and PI3K/AKT, MAPK/ERK, and Smad signaling pathways were examined by Western blotting. The results showed collagen hydrogels have good biocompatibility, and cell proliferation increased after collagen type II treatment. Expressions of SOX9, aggrecan, and collagen type II were increased in a collagen type II dependent manner. Sulfate proteoglycan synthesis increased in proportion to collagen type II concentration. Only hADMSCs highly expressed NP cell marker KRT19 in collagen type II culture. Additionally, phosphorylated Smad3, which is associated with phosphorylated ERK, was increased after collagen type II-stimulation. The concentration and type of collagen affect hADMSC differentiation into NP cells. Collagen type II significantly ameliorates hADMSC differentiation into NP cells and promotes extracellular matrix synthesis. Therefore, anabolism of collagen type I and catabolism of type II may attenuate the differentiation and biosynthesis of transplanted stem cells. © 2016 International Union of Biochemistry and Molecular Biology.

A dependence of quasielastic charged-current neutrino-nucleus cross sections

Science.gov (United States)

Van Dessel, N.; Jachowicz, N.; González-Jiménez, R.; Pandey, V.; Van Cuyck, T.

2018-04-01

Background: 12C has been and is still widely used in neutrino-nucleus scattering and oscillation experiments. More recently, 40Ar has emerged as an important nuclear target for current and future experiments. Liquid argon time projection chambers (LArTPCs) possess various advantages in measuring electroweak neutrino-nucleus cross sections. Concurrent theoretical research is an evident necessity. Purpose: 40Ar is larger than 12C , and one expects nuclear effects to play a bigger role in reactions. We present inclusive differential and total cross section results for charged-current neutrino scattering on 40Ar and perform a comparison with 12C , 16O , and 56Fe targets, to find out about the A -dependent behavior of model predictions. Method: Our model starts off with a Hartree-Fock description of the nucleus, with the nucleons interacting through a mean field generated by an effective Skyrme force. Long-range correlations are introduced by means of a continuum random phase approximation approach. Further methods to improve the accuracy of model predictions are also incorporated in the calculations. Results: We present calculations for 12C , 16O , 40Ar , and 56Fe , showcasing differential cross sections over a broad range of kinematic values in the quasielastic regime. We furthermore show flux-folded results for 40Ar and we discuss the differences between nuclear responses. Conclusions: At low incoming energies and forward scattering we identify an enhancement in the 40Ar cross section compared to 12C , as well as in the high ω (low Tμ) region across the entire studied Eν range. The contribution to the folded cross section of the reaction strength at values of ω lower than 50 MeV for forward scattering is sizable.

Effective number of inelastically interacting nucleons in rare nucleus-nucleus production processes

International Nuclear Information System (INIS)

Korotkikh, V.L.; Lokhtin, I.P.

1992-01-01

A model of nucleus-nucleus interaction using one inelastic NN-interaction is suggested for the exclusive production processes with small cross-section. A-dependence nuclear coherent and incoherent production cross-section are predicted. 20 refs.; 4 figs

Reactive oxygen species in the paraventricular nucleus of the hypothalamus alter sympathetic activity during metabolic syndrome.

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JOSIANE CAMPOS CRUZ

2015-12-01

Full Text Available The paraventricular nucleus of the hypothalamus (PVN contains heterogeneous populations of neurons involved in autonomic and neuroendocrine regulation. The PVN plays an important role in the sympathoexcitatory response to increasing circulating levels of angiotensin II (Ang-II, which activates AT1 receptors in the circumventricular organs (OCVs, mainly in the subfornical organ (SFO. Circulating Ang-II induces a de novo synthesis of Ang-II in SFO neurons projecting to pre-autonomic PVN neurons. Activation of AT1 receptors induces intracellular increases in reactive oxygen species (ROS, leading to increases in sympathetic nerve activity (SNA. Chronic sympathetic nerve activation promotes a series of metabolic disorders that characterizes the metabolic syndrome (MetS: dyslipidemia, hyperinsulinemia, glucose intolerance, hyperleptinemia and elevated plasma hormone levels, such as noradrenaline, glucocorticoids, leptin, insulin and Ang-II. This review will discuss the contribution of our laboratory and others regarding the sympathoexcitation caused by peripheral Ang-II-induced reactive oxygen species along the subfornical organ and paraventricular nucleus of the hypothalamus. We hypothesize that this mechanism could be involved in metabolic disorders underlying MetS.

Alterations in blood glucose and plasma glucagon concentrations during deep brain stimulation in the shell region of the nucleus accumbens in rats

Directory of Open Access Journals (Sweden)

Charlene eDiepenbroek

2013-12-01

Full Text Available Deep brain stimulation (DBS of the nucleus accumbens (NAc is an effective therapy for obsessive compulsive disorder (OCD and is currently under investigation as a treatment for eating disorders. DBS of this area is associated with altered food intake and pharmacological treatment of OCD is associated with the risk of developing type 2 diabetes. Therefore we examined if DBS of the NAc-shell (sNAc influences glucose metabolism. Male Wistar rats were subjected to DBS, or sham stimulation, for a period of one hour. To assess the effects of stimulation on blood glucose and glucoregulatory hormones, blood samples were drawn before, during and after stimulation. Subsequently, all animals were used for quantitative assessment of Fos immunoreactivity in the lateral hypothalamic area (LHA using computerized image analysis. DBS of the sNAc rapidly increased plasma concentrations of glucagon and glucose while sham stimulation and DBS outside the sNAc were ineffective. In addition, the increase in glucose was dependent on DBS intensity. In contrast, the DBS-induced increase in plasma corticosterone concentrations was independent of intensity and region, indicating that the observed DBS-induced metabolic changes were not due to corticosterone release. Stimulation of the sNAc with 200 μA increased Fos immunoreactivity in the LHA compared to sham or 100 μA stimulated animals. These data show that DBS of the sNAc alters glucose metabolism in a region- and intensity dependent manner in association with neuronal activation in the LHA. Moreover, these data illustrate the need to monitor changes in glucose metabolism during DBS-treatment of OCD patients.

Identification of different subsets of lung cells using Raman microspectroscopy and whole cell nucleus isolation.

Science.gov (United States)

Pijanka, Jacek K; Stone, Nicholas; Rutter, Abigail V; Forsyth, Nicholas; Sockalingum, Ganesh D; Yang, Ying; Sulé-Suso, Josep

2013-09-07

Raman spectroscopy has been widely used to study its possible clinical application in cancer diagnosis. However, in order to make it into clinical practice, it is important that this technique is able not only to identify cancer cells from their normal counterparts, but also from the array of cells present in human tissues. To this purpose, we used Raman spectroscopy to assess whether this technique was able to differentiate not only between lung cancer cells and lung epithelial cells but also from lung fibroblasts. Furthermore, we studied whether the differences were due to cell lineage (epithelial versus fibroblast) or to different proliferative characteristics of cells, and where in the cell compartment these differences might reside. To answer these questions we studied cell cytoplasm, cell nucleus and isolated whole cell nuclei. Our data suggests that Raman spectroscopy can differentiate between lung cancer, lung epithelial cells and lung fibroblasts. More important, it can also differentiate between 2 cells from the same lineage (fibroblast) but with one of them rendered immortal and with an increased proliferative activity. Finally, it seems that the main spectral differences reside in the cell nucleus and that the study of isolated nuclei strengthens the differences between cells.

Double folding model of nucleus-nucleus potential: formulae, iteration method and computer code

International Nuclear Information System (INIS)

Luk'yanov, K.V.

2008-01-01

Method of construction of the nucleus-nucleus double folding potential is described. Iteration procedure for the corresponding integral equation is presented. Computer code and numerical results are presented

Subthalamic Nucleus Deep Brain Stimulation Alters Prefrontal Correlates of Emotion Induction.

Science.gov (United States)

Bick, Sarah K B; Folley, Bradley S; Mayer, Jutta S; Park, Sohee; Charles, P David; Camalier, Corrie R; Pallavaram, Srivatsan; Konrad, Peter E; Neimat, Joseph S

2017-04-01

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) improves motor symptoms in advanced Parkinson's disease. STN DBS may also affect emotion, possibly by impacting a parallel limbic cortico-striatal circuit. The objective of this study was to investigate changes in prefrontal cortical activity related to DBS during an emotion induction task. We used near infrared spectroscopy to monitor prefrontal cortex hemodynamic changes during an emotion induction task. Seven DBS patients were tested sequentially in the stimulation-on and stimulation-off states while on dopaminergic medication. Patients watched a series of positive, negative, and neutral videos. The general linear model was used to compare prefrontal oxygenated hemoglobin concentration between DBS states. Deep brain stimulation was correlated with prefrontal oxygenated hemoglobin changes relative to the stimulation off state in response to both positive and negative videos. These changes were specific to emotional stimuli and were not seen during neutral stimuli. These results suggest that STN stimulation influences the prefrontal cortical representation of positive and negative emotion induction. © 2016 International Neuromodulation Society.

Theory of and effects from elastoplasticity in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Noerenberg, W.; Technische Hochschule Darmstadt

1985-02-01

Elastoplasticity of finite Fermi systems results from a coherent coupling between collective and intrinsic degrees of freedom and subsequent equilibration essentially due to two-body collisions. Within a non-markovian transport-theoretical approach referred to as dissipative diabatic dynamics (DDD), elastoplastical forms the link between giant vibrations and overdamped motion of nuclear. Obersvable effects resulting from this non-markovian behaviour in nucleus-nucleus collisions are discussed. (orig.)

Study of η-nucleus interaction through the formation of η-nucleus ...

Indian Academy of Sciences (India)

Answer to this question will deeply enrich our understanding of -nucleus interaction which is not so well-understood. We review the experimental efforts for the search of -mesic nuclei and describe the physics motivation behind it. We present the description of an experiment for the search of -nucleus bound state using ...

Leishmania donovani infection induces anemia in hamsters by differentially altering erythropoiesis in bone marrow and spleen.

Directory of Open Access Journals (Sweden)

William P Lafuse

Full Text Available Leishmania donovani is a parasite that causes visceral leishmaniasis by infecting and replicating in macrophages of the bone marrow, spleen, and liver. Severe anemia and leucopenia is associated with the disease. Although immune defense mechanisms against the parasite have been studied, we have a limited understanding of how L. donovani alters hematopoiesis. In this study, we used Syrian golden hamsters to investigate effects of L. donovani infection on erythropoiesis. Infection resulted in severe anemia and leucopenia by 8 weeks post-infection. Anemia was associated with increased levels of serum erythropoietin, which indicates the hamsters respond to the anemia by producing erythropoietin. We found that infection also increased numbers of BFU-E and CFU-E progenitor populations in the spleen and bone marrow and differentially altered erythroid gene expression in these organs. In the bone marrow, the mRNA expression of erythroid differentiation genes (α-globin, β-globin, ALAS2 were inhibited by 50%, but mRNA levels of erythroid receptor (c-kit, EpoR and transcription factors (GATA1, GATA2, FOG1 were not affected by the infection. This suggests that infection has a negative effect on differentiation of erythroblasts. In the spleen, erythroid gene expression was enhanced by infection, indicating that the anemia activates a stress erythropoiesis response in the spleen. Analysis of cytokine mRNA levels in spleen and bone marrow found that IFN-γ mRNA is highly increased by L. donovani infection. Expression of the IFN-γ inducible cytokine, TNF-related apoptosis-inducing ligand (TRAIL, was also up-regulated. Since TRAIL induces erythroblasts apoptosis, apoptosis of bone marrow erythroblasts from infected hamsters was examined by flow cytometry. Percentage of erythroblasts that were apoptotic was significantly increased by L. donovani infection. Together, our results suggest that L. donovani infection inhibits erythropoiesis in the bone marrow by

Left nucleus accumbens atrophy in deficit schizophrenia: A preliminary study.

Science.gov (United States)

De Rossi, Pietro; Dacquino, Claudia; Piras, Fabrizio; Caltagirone, Carlo; Spalletta, Gianfranco

2016-08-30

A question that remains to be answered is whether schizophrenia can be characterized by a single etiopathophysiology or whether separate sub-syndromes should be differentiated to define specific mechanisms for each sub-type. Individuals affected by the deficit subtype of schizophrenia (DSZ) display avolitional/amotivational features that respond poorly to conventional treatments. Characterizing DSZ from a neuroanatomical point of view may help clarify this issue and develop new treatment strategies. To determine if DSZ is associated with structural alterations in specific deep grey matter structures linked to its key clinical features, 22 DSZ patients, 22 non-deficit schizophrenia (NDSZ) patients and 22 healthy controls (HC) were recruited for a case-control cross-sectional study. High-resolution magnetic resonance imaging was performed in all subjects and volumes of deep grey matter structures were measured using FreeSurfer. DSZ patients displayed smaller left accumbens volumes compared to both NDSZ patients and HC. Moreover, age and duration of illness were significantly associated with lower volume of the left accumbens in DSZ but not in NDSZ. Findings indicate that DSZ is associated with lower volume of the nucleus accumbens in the dominant hemisphere. This is consistent with the psychopathological features and functional impairments present in DSZ and thus indicates a potential mechanism. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Volume regulation and shape bifurcation in the cell nucleus.

Science.gov (United States)

Kim, Dong-Hwee; Li, Bo; Si, Fangwei; Phillip, Jude M; Wirtz, Denis; Sun, Sean X

2015-09-15

Alterations in nuclear morphology are closely associated with essential cell functions, such as cell motility and polarization, and correlate with a wide range of human diseases, including cancer, muscular dystrophy, dilated cardiomyopathy and progeria. However, the mechanics and forces that shape the nucleus are not well understood. Here, we demonstrate that when an adherent cell is detached from its substratum, the nucleus undergoes a large volumetric reduction accompanied by a morphological transition from an almost smooth to a heavily folded surface. We develop a mathematical model that systematically analyzes the evolution of nuclear shape and volume. The analysis suggests that the pressure difference across the nuclear envelope, which is influenced by changes in cell volume and regulated by microtubules and actin filaments, is a major factor determining nuclear morphology. Our results show that physical and chemical properties of the extracellular microenvironment directly influence nuclear morphology and suggest that there is a direct link between the environment and gene regulation. © 2015. Published by The Company of Biologists Ltd.

Nuclear organization during in vitro differentiation of porcine mesenchymal stem cells (MSCs) into adipocytes.

Science.gov (United States)

Stachecka, Joanna; Walczak, Agnieszka; Kociucka, Beata; Ruszczycki, Błażej; Wilczyński, Grzegorz; Szczerbal, Izabela

2018-02-01

Differentiation of progenitor cells into adipocytes is accompanied by remarkable changes in cell morphology, cytoskeletal organization, and gene expression profile. Mature adipocytes are filled with a large lipid droplet and the nucleus tends to move to the cell periphery. It was hypothesized that the differentiation process is also associated with changes of nuclear organization. The aim of this study was to determine the number and distribution of selected components of nuclear architecture during porcine in vitro adipogenesis. The pig is an important animal model sharing many similarities to humans at the anatomical, physiological, and genetic levels and has been recognized as a good model for human obesity. Thus, understanding how cellular structures important for fundamental nuclear processes may be altered during adipocyte differentiation is of great importance. Mesenchymal stem cells (MSCs) were derived from bone marrow (BM-MSCs) and adipose tissue (AD-MSCs) and were cultured for 7 days in the adipogenic medium. A variable differentiation potential of these cell populations towards adipogenic lineage was observed, and for further study, a comparative characteristic of the nuclear organization in BM-MSCs and AD-MSCs was performed. Nuclear substructures were visualized by indirect immunofluorescence (nucleoli, nuclear speckles, PML bodies, lamins, and HP1α) or fluorescence in situ hybridization (telomeres) on fixed cells at 0, 3, 5, and 7 days of differentiation. Comprehensive characterization of these structures, in terms of their number, size, dynamics, and arrangement in three-dimensional space of the nucleus, was performed. It was found that during differentiation of porcine MSCs into adipocytes, changes of nuclear organization occurred and concerned: (1) the nuclear size and shape; (2) reduced lamin A/C expression; and (3) reorganization of chromocenters. Other elements of nuclear architecture such as nucleoli, SC-35 nuclear speckles, and telomeres

Diesel exhaust particle exposure in vitro alters monocyte differentiation and function.

Directory of Open Access Journals (Sweden)

Nazia Chaudhuri

Full Text Available Air pollution by diesel exhaust particles is associated with elevated mortality and increased hospital admissions in individuals with respiratory diseases such as asthma and chronic obstructive pulmonary disease. During active inflammation monocytes are recruited to the airways and can replace resident alveolar macrophages. We therefore investigated whether chronic fourteen day exposure to low concentrations of diesel exhaust particles can alter the phenotype and function of monocytes from healthy individuals and those with chronic obstructive pulmonary disease. Monocytes were purified from the blood of healthy individuals and people with a diagnosis of chronic obstructive pulmonary disease. Monocyte-derived macrophages were generated in the presence or absence of diesel exhaust particles and their phenotypes studied through investigation of their lifespan, cytokine generation in response to Toll like receptor agonists and heat killed bacteria, and expression of surface markers. Chronic fourteen day exposure of monocyte-derived macrophages to concentrations of diesel exhaust particles >10 µg/ml caused mitochondrial and lysosomal dysfunction, and a gradual loss of cells over time both in healthy and chronic obstructive pulmonary disease individuals. Chronic exposure to lower concentrations of diesel exhaust particles impaired CXCL8 cytokine responses to lipopolysaccharide and heat killed E. coli, and this phenotype was associated with a reduction in CD14 and CD11b expression. Chronic diesel exhaust particle exposure may therefore alter both numbers and function of lung macrophages differentiating from locally recruited monocytes in the lungs of healthy people and patients with chronic obstructive pulmonary disease.

Expanding the action of duplex RNAs into the nucleus: redirecting alternative splicing

Science.gov (United States)

Liu, Jing; Hu, Jiaxin; Corey, David R.

2012-01-01

Double-stranded RNAs are powerful agents for silencing gene expression in the cytoplasm of mammalian cells. The potential for duplex RNAs to control expression in the nucleus has received less attention. Here, we investigate the ability of small RNAs to redirect splicing. We identify RNAs targeting an aberrant splice site that restore splicing and production of functional protein. RNAs can target sequences within exons or introns and affect the inclusion of exons within SMN2 and dystrophin, genes responsible for spinal muscular atrophy and Duchenne muscular dystrophy, respectively. Duplex RNAs recruit argonaute 2 (AGO2) to pre-mRNA transcripts and altered splicing requires AGO2 expression. AGO2 promotes transcript cleavage in the cytoplasm, but recruitment of AGO2 to pre-mRNAs does not reduce transcript levels, exposing a difference between cytoplasmic and nuclear pathways. Involvement of AGO2 in splicing, a classical nuclear process, reinforces the conclusion from studies of RNA-mediated transcriptional silencing that RNAi pathways can be adapted to function in the mammalian nucleus. These data provide a new strategy for controlling splicing and expand the reach of small RNAs within the nucleus of mammalian cells. PMID:21948593

Quark matter formation in high energy nucleus-nucleus collisions - predictions and observations

International Nuclear Information System (INIS)

Otterlund, I.

1983-01-01

In this talk I give a short summary of the recent discussion around predictions and possible observations of quark-gluon plasma and fireballs in ultrarelativistic nucleus-nucleus collisions. In particular this talk is focused on heavy ion reactions at 200 A GeV. (orig./HSI)

Alterations in the regulatory volume decrease (RVD) and swelling-activated Cl- current associated with neuroendocrine differentiation of prostate cancer epithelial cells.

NARCIS (Netherlands)

Lemonnier, L.; Lazarenko, R.; Shuba, Y.; Thebault, S.C.; Roudbaraki, M.; Lepage, G.; Prevarskaya, N.; Skryma, R.

2005-01-01

Neuroendocrine (NE) differentiation of prostate epithelial/basal cells is a hallmark of advanced, androgen-independent prostate cancer, for which there is no successful therapy. Here we report for the first time on alterations in regulatory volume decrease (RVD) and its key determinant,

Lipid remodeling and an altered membrane-associated proteome may drive the differential effects of EPA and DHA treatment on skeletal muscle glucose uptake and protein accretion.

Science.gov (United States)

Jeromson, Stewart; Mackenzie, Ivor; Doherty, Mary K; Whitfield, Phillip D; Bell, Gordon; Dick, James; Shaw, Andy; Rao, Francesco V; Ashcroft, Stephen P; Philp, Andrew; Galloway, Stuart D R; Gallagher, Iain; Hamilton, D Lee

2018-06-01

In striated muscle, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have differential effects on the metabolism of glucose and differential effects on the metabolism of protein. We have shown that, despite similar incorporation, treatment of C 2 C 12 myotubes (CM) with EPA but not DHA improves glucose uptake and protein accretion. We hypothesized that these differential effects of EPA and DHA may be due to divergent shifts in lipidomic profiles leading to altered proteomic profiles. We therefore carried out an assessment of the impact of treating CM with EPA and DHA on lipidomic and proteomic profiles. Fatty acid methyl esters (FAME) analysis revealed that both EPA and DHA led to similar but substantials changes in fatty acid profiles with the exception of arachidonic acid, which was decreased only by DHA, and docosapentanoic acid (DPA), which was increased only by EPA treatment. Global lipidomic analysis showed that EPA and DHA induced large alterations in the cellular lipid profiles and in particular, the phospholipid classes. Subsequent targeted analysis confirmed that the most differentially regulated species were phosphatidylcholines and phosphatidylethanolamines containing long-chain fatty acids with five (EPA treatment) or six (DHA treatment) double bonds. As these are typically membrane-associated lipid species we hypothesized that these treatments differentially altered the membrane-associated proteome. Stable isotope labeling by amino acids in cell culture (SILAC)-based proteomics of the membrane fraction revealed significant divergence in the effects of EPA and DHA on the membrane-associated proteome. We conclude that the EPA-specific increase in polyunsaturated long-chain fatty acids in the phospholipid fraction is associated with an altered membrane-associated proteome and these may be critical events in the metabolic remodeling induced by EPA treatment.

Differential melatonin alterations in cerebrospinal fluid and serum of patients with major depressive disorder and bipolar disorder.

Science.gov (United States)

Bumb, J M; Enning, F; Mueller, J K; van der List, Till; Rohleder, C; Findeisen, P; Noelte, I; Schwarz, E; Leweke, F M

2016-07-01

Melatonin, which plays an important role for regulation of circadian rhythms and the sleep/wake cycle has been linked to the pathophysiology of major depressive and bipolar disorder. Here we investigated melatonin levels in cerebrospinal fluid (CSF) and serum of depression and bipolar patients to elucidate potential differences and commonalities in melatonin alterations across the two disorders. Using enzyme-linked immunosorbent assays, CSF and serum melatonin levels were measured in 108 subjects (27 healthy volunteers, 44 depressed and 37 bipolar patients). Covariate adjusted multiple regression analysis was used to investigate group differences in melatonin levels. In CSF, melatonin levels were significantly decreased in bipolar (Pdepressive disorder. In serum, we observed a significant melatonin decrease in major depressive (P=0.003), but not bipolar disorder. No associations were found between serum and CSF melatonin levels or between melatonin and measures of symptom severity or sleep disruptions in either condition. This study suggests the presence of differential, body fluid specific alterations of melatonin levels in bipolar and major depressive disorder. Further, longitudinal studies are required to explore the disease phase dependency of melatonin alterations and to mechanistically explore the causes and consequences of site-specific alterations. Copyright © 2016 Elsevier Inc. All rights reserved.

Distinct Histopathologic and Molecular Alterations in Inflammatory Bowel Disease-Associated Intestinal Adenocarcinoma: c-MYC Amplification is Common and Associated with Mucinous/Signet Ring Cell Differentiation.

Science.gov (United States)

Hartman, Douglas J; Binion, David G; Regueiro, Miguel D; Miller, Caitlyn; Herbst, Cameron; Pai, Reetesh K

2018-05-17

Chronic idiopathic inflammatory bowel disease (IBD) is a significant risk factor for the development of intestinal adenocarcinoma. The underlying molecular alterations in IBD-associated intestinal adenocarcinoma remain largely unknown. We compared the clinicopathologic and molecular features of 35 patients with 47 IBD-associated intestinal adenocarcinomas with a consecutive series of 451 patients with sporadic colorectal carcinoma identified at our institution and published data on sporadic colorectal carcinoma. c-MYC amplification was the most frequent molecular alteration identified in 33% of IBD-associated intestinal adenocarcinoma that is a significantly higher frequency than in sporadic colorectal carcinoma (8%) (P = 0.0001). Compared to sporadic colorectal carcinoma, IBD-associated intestinal adenocarcinomas more frequently demonstrated mucinous differentiation (60% vs 25%, P < 0.001) and signet ring cell differentiation (28% vs 4%, P < 0.001). Mucinous and signet ring cell differentiation were significantly associated with the presence of c-MYC amplification (both with P < 0.05). HER2 positivity (11%), KRAS exon 2 or 3 mutation (10%), and IDH1 mutation (7%) were less commonly observed in IBD-associated intestinal adenocarcinoma. There was an association between poor survival and HER2 status with 3 of 4 patients having HER2-positive adenocarcinoma dead of disease at last clinical follow-up; however, no statistically significant survival effect was identified for any of the molecular alterations identified. We demonstrate that IBD-associated intestinal adenocarcinomas have a high frequency of c-MYC amplification that is associated with mucinous and signet ring cell differentiation. Many of the identified molecular alterations have potential therapeutic relevance, including HER2 amplification, IDH1 mutation, and low frequency KRAS mutation.

A new version of PIRK (elastic pion-nucleus scattering) to handle differing proton and neutron radii

International Nuclear Information System (INIS)

Funsten, H.O.

1979-01-01

This program is a modification of the Eisenstein-Miller program (1974) for calculating elastic pion-nucleus differential cross sections using free π-N scattering amplitudes. This revision permits the use of separate proton and neutron radii for the nuclear density function rho(r). (Auth.)

The intercalatus nucleus of Staderini.

Science.gov (United States)

Cascella, Marco

2016-01-01

Rutilio Staderini was one of the leading Italian anatomists of the twentieth century, together with some scientists, such as Giulio Chiarugi, Giovanni Vitali, and others. He was also a member of a new generation of anatomists. They had continued the tradition of the most famous Italian scientists, which started from the Renaissance up until the nineteenth century. Although he carried out important studies of neuroanatomy and comparative anatomy, as well as embryology, his name is rarely remembered by most medical historians. His name is linked to the nucleus he discovered: the Staderini nucleus or intercalated nucleus, a collection of nerve cells in the medulla oblongata located lateral to the hypoglossal nucleus. This article focuses on the biography of the neuroanatomist as well as the nucleus that carries his name and his other research, especially on comparative anatomy and embryology.

Dynamics of hadronization in ultra-relativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Friman, B.L.

1986-01-01

One of the main problems in the search for quark-gluon plasma in ultra-relativistic nucleus-nucleus collisions is finding a reliable signature for deconfinement. Several signatures have been suggested, e.g., dileptons with a spectrum characteristic of the plasma, an increase in the number of strange particles and effects due to the hadronization of the plasma. In this talk I will describe some recent work on the effects of the hadronization transition in the central rapidity region within the hydrodynamic model of Bjorken, Kajantie and McLerran. (orig.)

Xenobiotics that affect oxidative phosphorylation alter differentiation of human adipose-derived stem cells at concentrations that are found in human blood

Directory of Open Access Journals (Sweden)

Laura Llobet

2015-11-01

Full Text Available Adipogenesis is accompanied by differentiation of adipose tissue-derived stem cells to adipocytes. As part of this differentiation, biogenesis of the oxidative phosphorylation system occurs. Many chemical compounds used in medicine, agriculture or other human activities affect oxidative phosphorylation function. Therefore, these xenobiotics could alter adipogenesis. We have analyzed the effects on adipocyte differentiation of some xenobiotics that act on the oxidative phosphorylation system. The tested concentrations have been previously reported in human blood. Our results show that pharmaceutical drugs that decrease mitochondrial DNA replication, such as nucleoside reverse transcriptase inhibitors, or inhibitors of mitochondrial protein synthesis, such as ribosomal antibiotics, diminish adipocyte differentiation and leptin secretion. By contrast, the environmental chemical pollutant tributyltin chloride, which inhibits the ATP synthase of the oxidative phosphorylation system, can promote adipocyte differentiation and leptin secretion, leading to obesity and metabolic syndrome as postulated by the obesogen hypothesis.

Characterization of the effects of serotonin on the release of [3H]dopamine from rat nucleus accumbens and striatal slices

International Nuclear Information System (INIS)

Nurse, B.; Russell, V.A.; Taljaard, J.J.

1988-01-01

The effect of serotonin agonists on the depolarization (K+)-induced, calcium-dependent, release of [ 3 H]dopamine (DA) from rat nucleus accumbens and striatal slices was investigated. Serotonin enhanced basal 3 H overflow and reduced K+-induced release of [ 3 H]DA from nucleus accumbens slices. The effect of serotonin on basal 3 H overflow was not altered by the serotonin antagonist, methysergide, or the serotonin re-uptake blocker, chlorimipramine, but was reversed by the DA re-uptake carrier inhibitors nomifensine and benztropine. With the effect on basal overflow blocked, serotonin did not modulate K+-induced release of [ 3 H]DA in the nucleus accumbens or striatum. The serotonin agonists, quipazine (in the presence of nomifensine) and 5-methoxytryptamine, did not significantly affect K+-induced release of [ 3 H]DA in the nucleus accumbens. This study does not support suggestions that serotonin receptors inhibit the depolarization-induced release of dopamine in the nucleus accumbens or striatum of the rat brain. The present results do not preclude the possibility that serotonin may affect the mesolimbic reward system at a site which is post-synaptic to dopaminergic terminals in the nucleus accumbens

Utility of susceptibility-weighted MRI in differentiating Parkinson's disease and atypical parkinsonism

International Nuclear Information System (INIS)

Gupta, Deepak; Saini, Jitender; Kesavadas, Chandrasekharan; Sarma, P.S.; Kishore, Asha

2010-01-01

Neuropathological studies report varying patterns of brain mineralization in Parkinson's diseases (PD), progressive supranuclear palsy (PSP), and Parkinson variant of multiple system atrophy (MSA-P). Susceptibility-weighted imaging (SWI) is the ideal magnetic resonance imaging (MRI) technique to detect mineralization of the brain. The purpose of this study was to test if SWI can differentiate PD, PSP, and MSA-P. Eleven patients with PD, 12 with PSP, 12 with MSA-P, and 11 healthy controls underwent SWI of the brain. Hypointensity of putamen, red nucleus, substantia nigra, and dentate nucleus in all groups were measured using an objective grading scale and scored from 0 to 3. In PSP, hypointensity score of red nucleus was higher than that in MSA-P (p = 0.001) and PD (p = 0.001), and a score of ≥2 differentiated the PSP group from the PD and MSA-P groups. Putaminal hypointensity score was higher in PSP when compared to that in PD (p = 0.003), and a score of ≥2 differentiated PSP from PD groups. SWI hypointensity scores of red nucleus and putamen had an excellent intrarater and interrater correlation. Substantia nigra hypointensity score of the PSP group was higher than that of the MSA-P (p = 0.004) and PD (p = 0.006) groups, but the scores had only a moderate intrarater and interrater correlation. SWI shows different patterns of brain mineralization in clinically diagnosed groups of PD, PSP, and MSA-P and may be considered as an additional MR protocol to help differentiate these conditions. (orig.)

The picture of the nuclei disintegration mechanism - from hadron-nucleus and nucleus-nucleus collisions experimental investigations at high energies

International Nuclear Information System (INIS)

Strugalska-Gola, E.; Strugalski, Z.; Chmielowski, W.

1997-01-01

The mechanism of the nuclei disintegration process in collisions of high-energy hadrons with nuclei is revealed experimentally. The disintegration appears as a complicated nuclear process developing in time and space in intranuclear matter, consisting at least of three stages which last together about 10 -24 - 10 -17 s after the impact. At the first stage, which lasts about 10 -24 - 10 -22 s, fast nucleons are densely emitted and the target-nucleus is locally damaged. At the second stage, lasting about 10 -22 - 10 -1 7 s, the damaged and unstable residual target nucleus uses to evaporate light fragments - mainly nucleons, deuterons, tritons, α-particles. At the final stage, the residual target-nucleus uses to split sometimes into two or more nuclear fragments

Proton rapidity distribution in nucleus-nucleus collisions at high energy

International Nuclear Information System (INIS)

Liu, F.H.

2002-01-01

The proton rapidity distributions in nucleus-nucleus collisions at the Alternating Gradient Synchrotron (AGS) and the Super Proton Synchrotron (SPS) energies are analysed by the revised thermalized cylinder model. The calculated results are compared and found to he in agreement with the experimental data of Si-AI and Si-Pb collisions at 14.6 A GeV/c, Pb-Pb collisions at 158 A GeV/c, and S-S collisions at 200 A GeV/c. (Author)

ψ' and J/ψ suppression in high-energy nucleon-nucleus and nucleus-nucleus collisions

International Nuclear Information System (INIS)

Wong, Cheuk-Yin.

1995-01-01

The observed features of ψ' to J/ψ suppression in pA and nucleus-nucleus collisions can be explained in terms of a two-component absorption model. For the hard component of the absorption due to the interaction of the produced c bar c systems with baryons at high relative energies, the absorption cross sections are insensitive to the radii of the c bar c systems, as described by the Additive Quark Model. For the soft component due to the low energy c bar c interactions with soft particles produced by other baryon-baryon collisions, the absorption cross sections are greater for ψ' than for J/ψ, because the breakup threshold for ψ' is much smaller than for ψ

Heat shock gene expression and cytoskeletal alterations in mouse neuroblastoma cells

NARCIS (Netherlands)

Bergen en Henegouwen, P.M.P. van; Linnemans, W.A.M.

The cytoskeleton of neuroblastoma cells, clone Neuro 2A, is altered by two stress conditions: heat shock and arsenite treatment. Microtubules are reorganized, intermediate filaments are aggregated around the nucleus, and the number of stress fibers is reduced. Since both stress modalities induce

HLXB9 gene expression, and nuclear location during in vitro neuronal differentiation in the SK-N-BE neuroblastoma cell line.

Directory of Open Access Journals (Sweden)

Claudia Giovanna Leotta

Full Text Available Different parts of the genome occupy specific compartments of the cell nucleus based on the gene content and the transcriptional activity. An example of this is the altered nuclear positioning of the HLXB9 gene in leukaemia cells observed in association with its over-expression. This phenomenon was attributed to the presence of a chromosomal translocation with breakpoint proximal to the HLXB9 gene. Before becoming an interesting gene in cancer biology, HLXB9 was studied as a developmental gene. This homeobox gene is also known as MNX1 (motor neuron and pancreas homeobox 1 and it is relevant for both motor neuronal and pancreatic beta cells development. A spectrum of mutations in this gene are causative of sacral agenesis and more broadly, of what is known as the Currarino Syndrome, a constitutional autosomal dominant disorder. Experimental work on animal models has shown that HLXB9 has an essential role in motor neuronal differentiation. Here we present data to show that, upon treatment with retinoic acid, the HLXB9 gene becomes over-expressed during the early stages of neuronal differentiation and that this corresponds to a reposition of the gene in the nucleus. More precisely, we used the SK-N-BE human neuroblastoma cell line as an in vitro model and we demonstrated a transient transcription of HLXB9 at the 4th and 5th days of differentiation that corresponded to the presence, predominantly in the cell nuclei, of the encoded protein HB9. The nuclear positioning of the HLXB9 gene was monitored at different stages: a peripheral location was noted in the proliferating cells whereas a more internal position was noted during differentiation, that is while HLXB9 was transcriptionally active. Our findings suggest that HLXB9 can be considered a marker of early neuronal differentiation, possibly involving chromatin remodeling pathways.

Field theoretical approach to proton-nucleus reactions: II-Multiple-step excitation process

International Nuclear Information System (INIS)

Eiras, A.; Kodama, T.; Nemes, M.

1989-01-01

A field theoretical formulation to multiple step excitation process in proton-nucleus collision within the context of a relativistic eikonal approach is presented. A closed form expression for the double differential cross section can be obtained whose structure is very simple and makes the physics transparent. Glauber's formulation of the same process is obtained as a limit of ours and the necessary approximations are studied and discussed. (author) [pt

The Baryon Production and Baryon Number Transfer in Hadron-Hadron, Hadron-Nucleus and Nucleus-Nucleus Collisions

International Nuclear Information System (INIS)

Szymanski, P.

2006-09-01

This work concerns soft hadronic interactions which in the Standard Model carry most of the observable cross-section but are not amenable to quantitative predictions due to the very nature of the QCD (Theory of Strong Interactions). In the low momentum transfer region the evolving coupling constant caused perturbation theory to break down. In this situation better experimental understanding of the physics phenomena is needed. One aspect of the soft hadronic interactions will be discussed in this work: transfer of the baryon number from the initial to the final state of the interaction. The past experimental knowledge on this process is presented, reasons for its unsatisfactory status are discussed and condition necessary for improvement are outlined: that is experimental apparatus with superior performance over the full range of available interactions: hadron-hadron collision, hadron-nucleus and nucleus-nucleus interactions. A consistent model-independent picture of the baryon number transfer process emerging from the data on the full range of interactions is shown. It offers serious challenge to theory to provide quantitative and detailed explanation of the measurements. (author)

Mirna biogenesis pathway is differentially regulated during adipose derived stromal/stem cell differentiation.

Science.gov (United States)

Martin, E C; Qureshi, A T; Llamas, C B; Burow, M E; King, A G; Lee, O C; Dasa, V; Freitas, M A; Forsberg, J A; Elster, E A; Davis, T A; Gimble, J M

2018-02-07

Stromal/stem cell differentiation is controlled by a vast array of regulatory mechanisms. Included within these are methods of mRNA gene regulation that occur at the level of epigenetic, transcriptional, and/or posttranscriptional modifications. Current studies that evaluate the posttranscriptional regulation of mRNA demonstrate microRNAs (miRNAs) as key mediators of stem cell differentiation through the inhibition of mRNA translation. miRNA expression is enhanced during both adipogenic and osteogenic differentiation; however, the mechanism by which miRNA expression is altered during stem cell differentiation is less understood. Here we demonstrate for the first time that adipose-derived stromal/stem cells (ASCs) induced to an adipogenic or osteogenic lineage have differences in strand preference (-3p and -5p) for miRNAs originating from the same primary transcript. Furthermore, evaluation of miRNA expression in ASCs demonstrates alterations in both miRNA strand preference and 5'seed site heterogeneity. Additionally, we show that during stem cell differentiation there are alterations in expression of genes associated with the miRNA biogenesis pathway. Quantitative RT-PCR demonstrated changes in the Argonautes (AGO1-4), Drosha, and Dicer at intervals of ASC adipogenic and osteogenic differentiation compared to untreated ASCs. Specifically, we demonstrated altered expression of the AGOs occurring during both adipogenesis and osteogenesis, with osteogenesis increasing AGO1-4 expression and adipogenesis decreasing AGO1 gene and protein expression. These data demonstrate changes to components of the miRNA biogenesis pathway during stromal/stem cell differentiation. Identifying regulatory mechanisms for miRNA processing during ASC differentiation may lead to novel mechanisms for the manipulation of lineage differentiation of the ASC through the global regulation of miRNA as opposed to singular regulatory mechanisms.

Production of strange and multistrange hadrons in nucleus-nucleus collisions at the SPS

Czech Academy of Sciences Publication Activity Database

Antinori, F.; Bakke, H.; Beusch, W.; Staroba, Pavel; Závada, Petr

1999-01-01

Roč. 661, - (1999), 130c-139c ISSN 0375-9474 Institutional research plan: CEZ:AV0Z1010920 Keywords : production * nucleus-nucleus collisions * hadrons * strangeness * model predictions Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 2.088, year: 1999

Particle production in high energy nucleus--nucleus experiments at Berkeley

International Nuclear Information System (INIS)

Schroeder, L.S.

1976-09-01

A review of high energy nucleus-nucleus experiments performed at the Berkeley Bevalac is presented. Earlier results on projectile and target fragmentation and pion production are briefly summarized. More recent results on Coulomb effects in projectile fragmentation, heavy ion total cross-sections, γ-ray production, and charged particle multiplicities are presented. Also, recent experiments which may shed light on phenomena arising from the central collision of two energetic nuclei, including recent evidence for and against the observation of nuclear shock waves, are reviewed

Mechanical response and buckling of a polymer simulation model of the cell nucleus

Science.gov (United States)

Banigan, Edward; Stephens, Andrew; Marko, John

The cell nucleus must robustly resist extra- and intracellular forces to maintain genome architecture. Micromanipulation experiments measuring nuclear mechanical response reveal that the nucleus has two force response regimes: a linear short-extension response due to the chromatin interior and a stiffer long-extension response from lamin A, comprising the intermediate filament protein shell. To explain these results, we developed a quantitative simulation model with realistic parameters for chromatin and the lamina. Our model predicts that crosslinking between chromatin and the lamina is essential for responding to small strains and that changes to the interior topological organization can alter the mechanical response of the whole nucleus. Thus, chromatin polymer elasticity, not osmotic pressure, is the dominant regulator of this force response. Our model reveals a novel buckling transition for polymer shells: as force increases, the shell buckles transverse to the applied force. This transition, which arises from topological constrains in the lamina, can be mitigated by tuning the properties of the chromatin interior. Thus, we find that the genome is a resistive mechanical element that can be tuned by its organization and connectivity to the lamina.

The nucleus

International Nuclear Information System (INIS)

Marano, S.

1998-01-01

In 1911 E.Rutherford discovered the nucleus. Since then the nucleus has been investigated with more and more powerful tools but it remains the main field of study of nuclear physics. As it is impossible to take into account the interaction of all the nucleons, a theory based on the hypothesis that each nucleon undergoes an average interaction force has been set up. 2 representations have emerged: the Skyrme force and the Gogny force. Both representations match experimental results but are unable to describe fission yields or the multi-fragmentation of very hot nuclei. The mean-field theory can predict the shape of the nuclei according to its energy level. An experimental program involving the Vivitron accelerator and the Euroball detector is due to begin to validate it. By bombarding targets with exotic nuclei nuclear physicists detect new structures and test their collision models. About ten years ago nuclear halos were observed with lithium 11 nuclei. In this nucleus 2 neutrons move in a space larger than the nucleus itself. This discovery has triggered the elaboration of new theories based on nuclear clusters. At very high temperatures the mean-field theory predicts that nuclear matter acts as a fluid. Following the nuclei temperature different ways of decay appear: first evaporation then multi-fragmentation and vaporization. This ultimate stage occurs around 100 milliard celsius degree temperature when the nuclei decays in a multitude of light particles. Isomeric states are studied and could be seen as a way of storing energy. In a very pedagogical way this article gives information to understand the challenges that face nuclear physics today and highlights the contributions of Cea in this field. (A.C.)

Different surface sensing of the cell body and nucleus in healthy primary cells and in a cancerous cell line on nanogrooves.

Science.gov (United States)

Davidson, Patricia M; Bigerelle, Maxence; Reiter, Günter; Anselme, Karine

2015-10-01

Cancer cells are known to have alterations compared to healthy cells, but can these differences extend to the way cells interact with their environment? Here, the authors focused on the alignment on an array of grooves of nanometer depth using two cell types: healthy osteoprogenitor primary cells (HOP) and a cancerous osteosarcoma (SaOs-2) cell line. Another concern was how this alignment affects the cell's interior, namely, the nucleus. Based on the results, it is proposed that these two cell types respond to different size regimes: SaOs-2 cells are more sensitive to shallow grooves while HOP cells are strongly aligned with deep grooves. As a measure of the impact of cell alignment on the nucleus the orientation and elongation of the nucleus were determined. Compared to HOP cells, the cell nucleus of SaOs-2 cells is more aligned and elongated in response to grooves, suggesting a softer nucleus and/or increased force transmission. These results support the hypothesis that cancer cells have reduced nucleus rigidity compared to healthy ones and further indicate differences in sensing, which may be important during metastasis.

Chronic suppression of μ-opioid receptor signaling in the nucleus accumbens attenuates development of diet-induced obesity in rats.

Science.gov (United States)

Lenard, N R; Zheng, H; Berthoud, H-R

2010-06-01

To test the hypothesis that micro-opioid receptor signaling in the nucleus accumbens contributes to hedonic (over)eating and obesity. To investigate the effects of chronic micro-opioid antagonism in the nucleus accumbens core or shell on intake of a palatable diet, and the development of diet-induced obesity in rats. Chronic blockade of micro-opioid receptor signaling in the nucleus accumbens core or shell was achieved by means of repeated injections (every 4-5 days) of the irreversible receptor antagonist beta-funaltrexamine (BFNA) over 3-5 weeks. The diet consisted of either a choice of high-fat chow, chocolate-flavored Ensure and regular chow (each nutritionally complete) or regular chow only. Intake of each food item, body weight and body fat mass were monitored throughout the study. The BFNA injections aimed at either the core or shell of the nucleus accumbens resulted in significantly attenuated intake of palatable diet, body weight gain and fat accretion, compared with vehicle control injections. The injection of BFNA in the core did not significantly change these parameters in chow-fed control rats. The injection of BFNA in the core and shell differentially affected intake of the two palatable food items: in the core, BFNA significantly reduced the intake of high-fat, but not of Ensure, whereas in the shell, it significantly reduced the intake of Ensure, but not of high-fat, compared with vehicle treatment. Endogenous micro-opioid receptor signaling in the nucleus accumbens core and shell is necessary for palatable diet-induced hyperphagia and obesity to fully develop in rats. Sweet and non-sweet fatty foods may be differentially processed in subcomponents of the ventral striatum.

Apoptosis during sexual differentiation of the bed nucleus of the stria terminalis in the rat brain

NARCIS (Netherlands)

Chung, W. C.; Swaab, D. F.; de Vries, G. J. [=Geert J.

2000-01-01

The bed nucleus of the stria terminalis (BST) in the rat forebrain differs between males and females. To test whether apoptosis may contribute to the development of sex differences in the BST, the incidence of apoptosis was determined in sham-treated males and sham-treated females sacrificed on

Oscillations in Pedunculopontine Nucleus in Parkinson's disease and its relationship with deep brain stimulation

Directory of Open Access Journals (Sweden)

Min eLi

2015-09-01

Full Text Available The recent development of deep brain stimulation (DBS of the pedunculopontine nucleus (PPN for the treatment of parkinsonian patients, particularly those in advanced stages with axial symptoms, has ignited interest into the study of this brain nucleus. In contrast to the extensively studied alterations of neural activity that occur in the basal ganglia in Parkinson’s disease (PD, our understanding of the activity of the PPN remains insufficient. In recent years, however, a series of studies recording oscillatory activity in the PPN of parkinsonian patients have made important findings. Here, we briefly review recent studies that explore the different kinds of oscillations observed in the PPN of parkinsonian patients, and how they underlie the pathophysiology of PD and the efficacy of PPN DBS in these disorders.

RIMA-dependent nuclear accumulation of IYO triggers auxin-irreversible cell differentiation in arabidopsis

NARCIS (Netherlands)

Muñoz, Alfonso; Mangano, Silvina; González-García, Mary Paz; Contreras, Ramón; Sauer, Michael; Rybel, De Bert; Weijers, Dolf; Sánchez-Serrano, José Juan; Sanmartín, Maite; Rojo, Enrique

2017-01-01

The transcriptional regulator MINIYO (IYO) is essential and rate-limiting for initiating cell differentiation in Arabidopsis thaliana. Moreover, IYO moves from the cytosol into the nucleus in cells at the meristem periphery, possibly triggering their differentiation. However, the genetic mechanisms

Dissipation in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Santanu Pal

1984-01-01

This paper deals with the mechanism of one- and two-body dissipations in nucleus-nucleus collisions. The average energy transferred to nuclear excitations is calculated using a time-dependent density matrix approach with lowest-order approximations. Considering the nuclei as Fermi gases, and using a gaussian-type NN interaction as the basic perturbation, simplified expressions are obtained for energy dissipations. These expressions are quite instructive to follow a number of interesting aspects of one- and two-body dissipations. It is theoretically observed that the memory time for the two-body dissipation is significantly smaller than that of one-body dissipation. A threshold-type dependence of the transferred energy on the relative velocity between the two nuclei is also observed. This threshold velocity is found to be related with the intrinsic nucleon kinetic energy for two-body dissipation and with the nuclear size for the one-body case. This observation further suggests that the total dissipated energy is shared between the two nuclei approximately in the ratio of their masses. The physical origin of these observations is also explained. Numerical calculations further illustrate some characteristic features of one- and two-body dissipations. (orig.)

Single nucleon emission in relativistic nucleus-nucleus reactions

International Nuclear Information System (INIS)

Anon.

1992-01-01

Significant discrepancies between theory and experiment have previously been noted for nucleon emission via electromagnetic processes in relativistic nucleus-nucleus collisions. The present work investigates the hypothesis that these discrepancies have arisen due to uncertainties about how to deduce the experimental electromagnetic cross section from the total measured cross section. An optical-model calculation of single neutron removal is added to electromagnetic cross sections and compared to the total experimental cross sections. Good agreement is found thereby resolving some of the earlier noted discrepancies. A detailed comparison to the recent work of Benesh, Cook, and Vary is made for both the impact parameter and the nuclear cross section. Good agreement is obtained giving an independent confirmation of the parameterized formulas developed by those authors

Nuclear translocation of the cytoskeleton-associated protein, smALP, upon induction of skeletal muscle differentiation

International Nuclear Information System (INIS)

Cambier, Linda; Pomies, Pascal

2011-01-01

Highlights: → The cytoskeleton-associated protein, smALP, is expressed in differentiated skeletal muscle. → smALP is translocated from the cytoplasm to the nucleus of C2C12 myoblasts upon induction of myogenesis. → The differentiation-dependent nuclear translocation of smALP occurs in parallel with the nuclear accumulation of myogenin. → The LIM domain of smALP is essential for the nuclear accumulation of the protein. → smALP might act in the nucleus to control some critical aspect of the muscle differentiation process. -- Abstract: The skALP isoform has been shown to play a critical role in actin organization and anchorage within the Z-discs of skeletal muscles, but no data is available on the function of the smALP isoform in skeletal muscle cells. Here, we show that upon induction of differentiation a nuclear translocation of smALP from the cytoplasm to the nucleus of C2C12 myoblasts, concomitant to an up-regulation of the protein expression, occurs in parallel with the nuclear accumulation of myogenin. Moreover, we demonstrate that the LIM domain of smALP is essential for the nuclear translocation of the protein.

Direct projection from the suprachiasmatic nucleus to hypophysiotrophic corticotropin-releasing factor immunoreactive cells in the paraventricular nucleus of the hypothalamus demonstrated...

DEFF Research Database (Denmark)

Vrang, N.; Larsen, P.J.; Mikkelsen, J.D.

1995-01-01

Suprachiasmatic nucleus, paraventricular nucleus, circadian rhythms, phaseolus vulgaris-leucoagglutinin, corticotropin-releasing factor, dual immunocytochemistry......Suprachiasmatic nucleus, paraventricular nucleus, circadian rhythms, phaseolus vulgaris-leucoagglutinin, corticotropin-releasing factor, dual immunocytochemistry...

Differential Functional Connectivity Alterations of Two Subdivisions within the Right dlPFC in Parkinson's Disease

Directory of Open Access Journals (Sweden)

Julian Caspers

2017-05-01

Full Text Available Patients suffering from Parkinson's disease (PD often show impairments in executive function (EF like decision-making and action control. The right dorsolateral prefrontal cortex (dlPFC has been strongly implicated in EF in healthy subjects and has repeatedly been reported to show alterations related to EF impairment in PD. Recently, two key regions for cognitive action control have been identified within the right dlPFC by co-activation based parcellation. While the posterior region is engaged in rather basal EF like stimulus integration and working memory, the anterior region has a more abstract, supervisory function. To investigate whether these functionally distinct subdivisions of right dlPFC are differentially affected in PD, we analyzed resting-state functional connectivity (FC in 39 PD patients and 44 age- and gender-matched healthy controls. Patients were examined both after at least 12 h withdrawal of dopaminergic drugs (OFF and under their regular dopaminergic medication (ON. We found that only the posterior right dlPFC subdivision shows FC alterations in PD, while the anterior part remains unaffected. PD-related decreased FC with posterior right dlPFC was found in the bilateral medial posterior parietal cortex (mPPC and left dorsal premotor region (PMd in the OFF state. In the medical ON, FC with left PMd normalized, while decoupling with bilateral mPPC remained. Furthermore, we observed increased FC between posterior right dlPFC and the bilateral dorsomedial prefrontal cortex (dmPFC in PD in the ON state. Our findings point to differential disturbances of right dlPFC connectivity in PD, which relate to its hierarchical organization of EF processing by stronger affecting the functionally basal posterior aspect than the hierarchically higher anterior part.

Double-differential heavy-ion production cross sections

International Nuclear Information System (INIS)

Miller, T. M.; Townsend, L. W.

2004-01-01

Current computational tools used for space or accelerator shielding studies transport energetic heavy ions either using a one-dimensional straight-ahead approximation or by dissociating the nuclei into protons and neutrons and then performing neutron and proton transport using Monte Carlo techniques. Although the heavy secondary particles generally travel close to the beam direction, a proper treatment of the light ions produced in these reactions requires that double-differential cross sections should be utilised. Unfortunately, no fundamental nuclear model capable of serving as an event generator to provide these cross sections for all ions and energies of interest exists currently. Herein, we present a model for producing double-differential heavy-ion production cross sections that uses heavy-ion fragmentation yields produced by the NUCFRG2 fragmentation code coupled with a model of energy degradation in nucleus-nucleus collisions and systematics of momentum distributions to provide energy and angular dependences of the heavy-ion production. (authors)

From synapse to nucleus and back again--communication over distance within neurons.

Science.gov (United States)

Fainzilber, Mike; Budnik, Vivian; Segal, Rosalind A; Kreutz, Michael R

2011-11-09

How do neurons integrate intracellular communication from synapse to nucleus and back? Here we briefly summarize aspects of this topic covered by a symposium at Neuroscience 2011. A rich repertoire of signaling mechanisms link both dendritic terminals and axon tips with neuronal soma and nucleus, using motor-dependent transport machineries to traverse the long intracellular distances along neuronal processes. Activation mechanisms at terminals include localized translation of dendritic or axonal RNA, proteolytic cleavage of receptors or second messengers, and differential phosphorylation of signaling moieties. Signaling complexes may be transported in endosomes, or as non-endosomal complexes associated with importins and dynein. Anterograde transport of RNA granules from the soma to neuronal processes, coupled with retrograde transport of proteins translated locally at terminals or within processes, may fuel ongoing bidirectional communication between soma and synapse to modulate synaptic plasticity as well as neuronal growth and survival decisions.

Moderate long-term modulation of neuropeptide Y in hypothalamic arcuate nucleus induces energy balance alterations in adult rats.

Directory of Open Access Journals (Sweden)

Lígia Sousa-Ferreira

Full Text Available Neuropeptide Y (NPY produced by arcuate nucleus (ARC neurons has a strong orexigenic effect on target neurons. Hypothalamic NPY levels undergo wide-ranging oscillations during the circadian cycle and in response to fasting and peripheral hormones (from 0.25 to 10-fold change. The aim of the present study was to evaluate the impact of a moderate long-term modulation of NPY within the ARC neurons on food consumption, body weight gain and hypothalamic neuropeptides. We achieved a physiological overexpression (3.6-fold increase and down-regulation (0.5-fold decrease of NPY in the rat ARC by injection of AAV vectors expressing NPY and synthetic microRNA that target the NPY, respectively. Our work shows that a moderate overexpression of NPY was sufficient to induce diurnal over-feeding, sustained body weight gain and severe obesity in adult rats. Additionally, the circulating levels of leptin were elevated but the immunoreactivity (ir of ARC neuropeptides was not in accordance (POMC-ir was unchanged and AGRP-ir increased, suggesting a disruption in the ability of ARC neurons to response to peripheral metabolic alterations. Furthermore, a dysfunction in adipocytes phenotype was observed in these obese rats. In addition, moderate down-regulation of NPY did not affect basal feeding or normal body weight gain but the response to food deprivation was compromised since fasting-induced hyperphagia was inhibited and fasting-induced decrease in locomotor activity was absent.These results highlight the importance of the physiological ARC NPY levels oscillations on feeding regulation, fasting response and body weight preservation, and are important for the design of therapeutic interventions for obesity that include the NPY.

Serotonin projection patterns to the cochlear nucleus.

Science.gov (United States)

Thompson, A M; Thompson, G C

2001-07-13

The cochlear nucleus is well known as an obligatory relay center for primary auditory nerve fibers. Perhaps not so well known is the neural input to the cochlear nucleus from cells containing serotonin that reside near the midline in the midbrain raphe region. Although the specific locations of the main, if not sole, sources of serotonin within the dorsal cochlear nucleus subdivision are known to be the dorsal and median raphe nuclei, sources of serotonin located within other cochlear nucleus subdivisions are not currently known. Anterograde tract tracing was used to label fibers originating from the dorsal and median raphe nuclei while fluorescence immunohistochemistry was used to simultaneously label specific serotonin fibers in cat. Biotinylated dextran amine was injected into the dorsal and median raphe nuclei and was visualized with Texas Red, while serotonin was visualized with fluorescein. Thus, double-labeled fibers were unequivocally identified as serotoninergic and originating from one of the labeled neurons within the dorsal and median raphe nuclei. Double-labeled fiber segments, typically of fine caliber with oval varicosities, were observed in many areas of the cochlear nucleus. They were found in the molecular layer of the dorsal cochlear nucleus, in the small cell cap region, and in the granule cell and external regions of the cochlear nuclei, bilaterally, of all cats. However, the density of these double-labeled fiber segments varied considerably depending upon the exact region in which they were found. Fiber segments were most dense in the dorsal cochlear nucleus (especially in the molecular layer) and the large spherical cell area of the anteroventral cochlear nucleus; they were moderately dense in the small cell cap region; and fiber segments were least dense in the octopus and multipolar cell regions of the posteroventral cochlear nucleus. Because of the presence of labeled fiber segments in subdivisions of the cochlear nucleus other than the

Actomyosin contractility rotates the cell nucleus.

Science.gov (United States)

Kumar, Abhishek; Maitra, Ananyo; Sumit, Madhuresh; Ramaswamy, Sriram; Shivashankar, G V

2014-01-21

The cell nucleus functions amidst active cytoskeletal filaments, but its response to their contractile stresses is largely unexplored. We study the dynamics of the nuclei of single fibroblasts, with cell migration suppressed by plating onto micro-fabricated patterns. We find the nucleus undergoes noisy but coherent rotational motion. We account for this observation through a hydrodynamic approach, treating the nucleus as a highly viscous inclusion residing in a less viscous fluid of orientable filaments endowed with active stresses. Lowering actin contractility selectively by introducing blebbistatin at low concentrations drastically reduced the speed and coherence of the angular motion of the nucleus. Time-lapse imaging of actin revealed a correlated hydrodynamic flow around the nucleus, with profile and magnitude consistent with the results of our theoretical approach. Coherent intracellular flows and consequent nuclear rotation thus appear to be an intrinsic property of cells.

Multi-quark effects in high energy nucleon-nucleon and nucleus-nucleus collisions

International Nuclear Information System (INIS)

Besliu, C.; Caraciuc, I.; Jipa, A.; Olariu, A.; Topor-Pop, R.; Cotorobai, F.; Pantea, D.; Popa, L.; Popa, V.; Topor-Pop, V.

1988-02-01

Recent data obtained in two experiments performed in the framework of the Bucharest-Dubna collaboration are presented, i.e.: the observation of narrow dibaryonic resonances is neutron-proton interactions in 1mHBC at different momenta of incident neutrons in the range 1-5 GeV/c, and the cumulative production of negative pions in nucleus-nucleus interactions in SKM-200 streamer chamber at 4.5 GeV/c. (authors)

Microscopic model of nucleus-nucleus collisions

International Nuclear Information System (INIS)

Harvey, B.G.

1986-04-01

The collision of two nuclei is treated as a collection of collisions between the nucleons of the projectile and those of the target nucleus. The primary projectile fragments contain only those nucleons that did not undergo a collision. The inclusive and coincidence cross sections result from the decay of the excited primary fragments. 15 refs., 5 figs

X-ray induced alterations in the differentiation and mineralization potential of murine preosteoblastic cells

Science.gov (United States)

Hu, Yueyuan; Lau, Patrick; Baumstark-Khan, Christa; Hellweg, Christine E.; Reitz, Günther

2012-05-01

To evaluate the effects of ionizing radiation (IR) on murine preosteoblastic cell differentiation, we directed OCT-1 cells to the osteoblastic lineage by treatment with a combination of β-glycerophosphate (β-GP), ascorbic acid (AA), and dexamethasone (Dex). In vitro mineralization was evaluated based on histochemical staining and quantification of the hydroxyapatite content of the extracellular bone matrix. Expression of mRNA encoding Runx2, transforming growth factor β1 (TGF-β1), osteocalcin (OCN), and p21CDKN1A was analyzed. Exposure to IR reduced the growth rate and diminished cell survival of OCT-1 cells under standard conditions. Notably, calcium content analysis revealed that deposition of mineralized matrix increased significantly under osteogenic conditions after X-ray exposure in a time-dependent manner. In this study, higher radiation doses exert significant overall effects on TGF-β1, OCN, and p21CDKN1A gene expression, suggesting that gene expression following X-ray treatment is affected in a dose-dependent manner. Additionally, we verified that Runx2 was suppressed within 24 h after irradiation at 2 and 4 Gy. Although further studies are required to verify the molecular mechanism, our observations strongly suggest that treatment with IR markedly alters the differentiation and mineralization process of preosteoblastic cells.

Alteration in neonatal nutrition causes perturbations in hypothalamic neural circuits controlling reproductive function.

Science.gov (United States)

Caron, Emilie; Ciofi, Philippe; Prevot, Vincent; Bouret, Sebastien G

2012-08-15

It is increasingly accepted that alterations of the early life environment may have lasting impacts on physiological functions. In particular, epidemiological and animal studies have indicated that changes in growth and nutrition during childhood and adolescence can impair reproductive function. However, the precise biological mechanisms that underlie these programming effects of neonatal nutrition on reproduction are still poorly understood. Here, we used a mouse model of divergent litter size to investigate the effects of early postnatal overnutrition and undernutrition on the maturation of hypothalamic circuits involved in reproductive function. Neonatally undernourished females display attenuated postnatal growth associated with delayed puberty and defective development of axonal projections from the arcuate nucleus to the preoptic region. These alterations persist into adulthood and specifically affect the organization of neural projections containing kisspeptin, a key neuropeptide involved in pubertal activation and fertility. Neonatal overfeeding also perturbs the development of neural projections from the arcuate nucleus to the preoptic region, but it does not result in alterations in kisspeptin projections. These studies indicate that alterations in the early nutritional environment cause lasting and deleterious effects on the organization of neural circuits involved in the control of reproduction, and that these changes are associated with lifelong functional perturbations.

Measure of back angle cross sections of antiproton-nucleus elastic scattering at 48 and 180 MeV

International Nuclear Information System (INIS)

Berrada, M.

1986-04-01

Antiproton-nucleus elastic scattering was studied in the LEAR ring at CERN. The scattering cross section at back angles (θ LAB = 142 to 164 deg inclusive) was measured using plastic scintillation detectors. Analysis of experimental data at 47 MeV for a CH target and at 182 MeV for CH, C12, 016, and 018 targets produces differential cross sections for back angles less than or equal to a few dozen microbarns. These results agree with theoretical microscopic predictions. The analysis improves understanding of antiproton-nucleus interaction and introduces a constraint on the construction of optical potentials. The antiproton-nucleus potential is shown to be highly absorbing, thereby excluding S type potentials, and removing the ambiguity arising from the analysis of antiprotonic atoms. The results also show that there is no attractive pocket in the real potential likely to lead to an increase of the back angle cross sections [fr

Mastication induces long-term increases in blood perfusion of the trigeminal principal nucleus.

Science.gov (United States)

Viggiano, A; Manara, R; Conforti, R; Paccone, A; Secondulfo, C; Lorusso, L; Sbordone, L; Di Salle, F; Monda, M; Tedeschi, G; Esposito, F

2015-12-17

Understanding mechanisms for vessel tone regulation within the trigeminal nuclei is of great interest because some headache syndromes are due to dysregulation of such mechanisms. Previous experiments on animal models suggest that mastication may alter neuron metabolism and blood supply in these nuclei. To investigate this hypothesis in humans, arterial spin-labeling magnetic resonance imaging (MRI) was used to measure blood perfusion within the principal trigeminal nucleus (Vp) and in the dorsolateral-midbrain (DM, including the mesencephalic trigeminal nucleus) in healthy volunteers, before and immediately after a mastication exercise consisting of chewing a gum on one side of the mouth for 1 h at 1 bite/s. The side preference for masticating was evaluated with a chewing test and the volume of the masseter muscle was measured on T1-weighted MRI scans. The results demonstrated that the mastication exercise caused a perfusion increase within the Vp, but not in the DM. This change was correlated to the preference score for the side where the exercise took place. Moreover, the basal Vp perfusion was correlated to the masseter volume. These results indicate that the local vascular tone of the trigeminal nuclei can be constitutively altered by the chewing practice and by strong or sustained chewing. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Random matrix theory and analysis of nucleus-nucleus collision at high energies

International Nuclear Information System (INIS)

Shahaliev, E.I.; Inst. of Radiation Problems, Baku; ); Kuznetsov, A.A.; Suleymanov, M.K.; ); Teryaev, O.V.; )

2006-01-01

A novel method for analysis of experimental data obtained at relativistic nucleus-nucleus collisions is proposed. The method, based on the ideas of Random Matrix Theory, is applied to detect systematic errors that occur at measurements of momentum distributions of emitted particles. The unfolded momentum distribution is well described by the Gaussian orthogonal ensemble of random matrices, when the uncertainty in the momentum distribution is maximal. The method is free from unwanted background contributions [ru

Differential cross section measurement of radiative capture of protons by nuclei 12C

International Nuclear Information System (INIS)

Burtebayev, N.; Zazulin, D.M.; Buminskii, V.P.; Zarifov, R.A.; Tohtarov, R.N.; Sagindykov, Sh.Sh.; Baktibayev, M.K.

2003-01-01

Measurements of differential cross sections of nuclear reaction 12 C(p, γ) 13 N at 0, 45, 90, 135 Deg. to beam direction of flying protons in the field of E p = 350-1100 KeV with an error it is not worse than 10 % have been carried out. Most important was studied, from the astrophysical point of view, process of capture of protons by nucleuses 12 C on the ground state of a nucleus 13 N. It is experimentally shown isotropy of angular distribution of differential cross sections of reaction 12 C(p, γ) 13 N, in the given field energy of protons

Color oscillations of nucleons in a nucleus

International Nuclear Information System (INIS)

Petrov, V.A.; Smirnov, A.Yu.

1987-01-01

Possibility of nucleus description as an object consisting of quarks and gluons is considered. A model of two-nucleon interaction in a nucleus is presented and analytical expressions for the nucleus nucleon ground state wave functions and also for nuclear nucleon structure functions are obtained. The carried out analysis shows that the suggested model permits to express the nucleus structure functions at quark level only by means of nucleon and Δ-isobaric degrees of freedom

Cocaine Exposure Reorganizes Cell-Type and Input-Specific Connectivity in the Nucleus Accumbens

Science.gov (United States)

MacAskill, Andrew F.; Cassel, John M.; Carter, Adam G.

2014-01-01

Exposure to cocaine alters the structural and functional properties of medium spiny neurons (MSNs) in the Nucleus Accumbens (NAc). These changes suggest a rewiring of the NAc circuit, with an enhancement of excitatory synaptic connections onto MSNs. However, it is unknown how drug exposure alters the balance of long-range afferents onto different cell types in the NAc. Here we use whole-cell recordings, two-photon microscopy, optogenetics and pharmacogenetics to show how repeated cocaine alters connectivity in the mouse NAc medial shell. We first determine that cocaine selectively enhances amygdala innervation of D1-MSNs relative to D2-MSNs. We then show that amygdala activity is required for cocaine-induced changes to behavior and connectivity. Finally, we establish how heightened amygdala innervation can explain the structural and functional changes induced by cocaine. Our findings reveal how exposure to drugs of abuse fundamentally reorganizes cell-type and input-specific connectivity in the NAc. PMID:25108911

Percolation Model of Nuclear Multifragmentation in High Energy Nucleus-Nucleus Interactions

International Nuclear Information System (INIS)

Abdel-Waged, Kh.

1994-01-01

A hybrid model based on Reggeon theory inspired model of nuclear distribution, which was successful in explaining the cascading of particles in high energy nucleus-nucleus interactions, and percolation model is proposed. In the framework of this model the yield of the fragment in p + Ag, Au at 350 GeV and C + Ag, Au at 3.6 GeV/nucleon as well as the charge distribution of fragments in Kr, Xe and U interactions with emulsion at ∼ 1 GeV/nucleon is correctly described. 32 refs., 3 figs

Descending projections from the nucleus accumbens shell excite activity of taste-responsive neurons in the nucleus of the solitary tract in the hamster.

Science.gov (United States)

Li, Cheng-Shu; Lu, Da-Peng; Cho, Young K

2015-06-01

The nucleus of the solitary tract (NST) and the parabrachial nuclei (PbN) are the first and second relays in the rodent central taste pathway. A series of electrophysiological experiments revealed that spontaneous and taste-evoked activities of brain stem gustatory neurons are altered by descending input from multiple forebrain nuclei in the central taste pathway. The nucleus accumbens shell (NAcSh) is a key neural substrate of reward circuitry, but it has not been verified as a classical gustatory nucleus. A recent in vivo electrophysiological study demonstrated that the NAcSh modulates the spontaneous and gustatory activities of hamster pontine taste neurons. In the present study, we investigated whether activation of the NAcSh modulates gustatory responses of the NST neurons. Extracellular single-unit activity was recorded from medullary neurons in urethane-anesthetized hamsters. After taste response was confirmed by delivery of sucrose, NaCl, citric acid, and quinine hydrochloride to the anterior tongue, the NAcSh was stimulated bilaterally with concentric bipolar stimulating electrodes. Stimulation of the ipsilateral and contralateral NAcSh induced firings from 54 and 37 of 90 medullary taste neurons, respectively. Thirty cells were affected bilaterally. No inhibitory responses or antidromic invasion was observed after NAcSh activation. In the subset of taste cells tested, high-frequency electrical stimulation of the NAcSh during taste delivery enhanced taste-evoked neuronal firing. These results demonstrate that two-thirds of the medullary gustatory neurons are under excitatory descending influence from the NAcSh, which is a strong indication of communication between the gustatory pathway and the mesolimbic reward pathway. Copyright © 2015 the American Physiological Society.

Fibroblast growth factor receptor (FGFR) alterations in squamous differentiated bladder cancer: a putative therapeutic target for a small subgroup.

Science.gov (United States)

Baldia, Philipp H; Maurer, Angela; Heide, Timon; Rose, Michael; Stoehr, Robert; Hartmann, Arndt; Williams, Sarah V; Knowles, Margaret A; Knuechel, Ruth; Gaisa, Nadine T

2016-11-01

Although drugable fibroblast growth factor receptor (FGFR) alterations in squamous cell carcinomas (SCC) of various entities are well known, little is known about FGFR modifications in squamous differentiated bladder cancer. Therefore, our study evaluated FGFR1-3 alterations as a putative therapeutic target in this subgroup. We analyzed 73 squamous differentiated bladder cancers (n = 10 pT2, n = 55 pT3, n = 8 pT4) for FGFR1-3 protein expression, FGFR1-3 copy number variations, FGFR3 chromosomal rearrangements (fluorescence in situ hybridization (FISH)) and FGFR3 mutations (SNapShot analysis). Only single cases displayed enhanced protein expression, most frequently FGFR3 overexpression (9.4% (6/64)). FISH showed no amplifications of FGFR1, 2 or 3. Break apart events were only slightly above the cut off in 12.1% (8/66) of cases and no FGFR3-TACC3 rearrangements could be proven by qPCR. FGFR3 mutations (p.S249C) were found in 8.5% (6/71) of tumors and were significantly associated with FGFR3 protein overexpression (p bladder cancer (n = 85), which revealed reduced overall expression of FGFR1 and FGFR2 in tumors compared to normal tissue, while expression of FGFR3 remained high. In the TCGA "squamous-like" subtype FGFR3 mutations were found in 4.9% and correlated with high FGFR3 RNA expression. Mutations of FGFR1 and FGFR2 were less frequent (2.4% and 1.2%). Hence, our comprehensive study provides novel insights into a subgroup of squamous differentiated bladder tumors that hold clues for novel therapeutic regimens and may benefit from FGFR3-targeted therapies.

Energy loss, range and fluence distributions, total reaction and projectile fragment production cross sections for proton-nucleus and nucleus-nucleus interactions

International Nuclear Information System (INIS)

Sihver, L.; Kanai, T.

1992-07-01

We have developed a computer code for calculations of energy loss (dE/dx) and range distributions for heavy ions in any media. The results from our calculations are in very good agreement with previous calculations. We have developed semiempirical total reaction cross section formulae for proton-nucleus (with Z p ≤26) and nucleus-nucleus (with Z p and Z t ≤26) reactions. These formulae apply for incident energies above 15 MeV and 100 MeV/nucleon respectively. From the total reaction cross sections, we can calculate the mean free paths and the fluence distributions of protons and heavy ions in any media. We have compared all the calculated reaction cross sections and the mean free paths with experimental data, and the agreement is good. We have also constructed a procedure for calculating projectile fragment production cross sections, by scaling semiempirical proton-nucleus partial cross section systematics. The scaling is performed using a scaling parameter deduced from our reaction cross sections formulae, and additional enhancements factors. All products with atomic number ranging from that of the projectile (Z p ) down to Z=2 can be calculated. The agreement between the calculated cross sections and the experimental data is better than earlier published results. (author)

Proteasome (Prosome Subunit Variations during the Differentiation of Myeloid U937 Cells

Directory of Open Access Journals (Sweden)

Laurent Henry

1997-01-01

Full Text Available 20S proteasomes (prosomes/multicatalytic proteinase are protein particles built of 28 subunits in variable composition. We studied the changes in proteasome subunit composition during the differentiation of U937 cells induced by phorbol‐myristate‐acetate or retinoic acid plus 1,25‐dihydroxy‐cholecalciferol by western blot, flow cytometry and immuno‐fluorescence. p25K (C3, p27K (IOTA and p30/33K (C2 subunits were detected in both the nucleus and cytoplasm of undifferentiated cells. Flow cytometry demonstrated a biphasic decrease in proteasome subunits detection during differentiation induced by RA+VD. PMA caused an early transient decrease in these subunits followed by a return to their control level, except for p30/33K, which remained low. Immuno‐fluorescence also showed differences in the cytolocalization of the subunits, with a particular decrease in antigen labeling in the nucleus of RA+VD‐induced cells, and a scattering in the cytoplasm and a reorganization in the nucleus of PMA‐induced cells. Small amounts of proteasomal proteins were seen on the outer membrane of non‐induced cells; these membrane proteins disappeared when treated with RA+VD, whereas some increased on PMA‐induced cells. The differential changes in the distribution and type of proteasomes in RA+VD and PMA‐induced cells indicate that, possibly, 20S proteasomes may play a role in relation to the mechanisms of differentiation and the inducer used.

Brain cytoplasmic RNA 1 suppresses smooth muscle differentiation and vascular development in mice.

Science.gov (United States)

Wang, Yung-Chun; Chuang, Ya-Hui; Shao, Qiang; Chen, Jian-Fu; Chen, Shi-You

2018-04-13

The cardiovascular system develops during the early stages of embryogenesis, and differentiation of smooth muscle cells (SMCs) is essential for that process. SMC differentiation is critically regulated by transforming growth factor (TGF)-β/SMAD family member 3 (SMAD3) signaling, but other regulators may also play a role. For example, long noncoding RNAs (lncRNAs) regulate various cellular activities and events, such as proliferation, differentiation, and apoptosis. However, whether long noncoding RNAs also regulate SMC differentiation remains largely unknown. Here, using the murine cell line C3H10T1/2, we found that brain cytoplasmic RNA 1 (BC1) is an important regulator of SMC differentiation. BC1 overexpression suppressed, whereas BC1 knockdown promoted, TGF-β-induced SMC differentiation, as indicated by altered cell morphology and expression of multiple SMC markers, including smooth muscle α-actin (αSMA), calponin, and smooth muscle 22α (SM22α). BC1 appeared to block SMAD3 activity and inhibit SMC marker gene transcription. Mechanistically, BC1 bound to SMAD3 via RNA SMAD-binding elements (rSBEs) and thus impeded TGF-β-induced SMAD3 translocation to the nucleus. This prevented SMAD3 from binding to SBEs in SMC marker gene promoters, an essential event in SMC marker transcription. In vivo , BC1 overexpression in mouse embryos impaired vascular SMC differentiation, leading to structural defects in the artery wall, such as random breaks in the elastic lamina, abnormal collagen deposition on SM fibers, and disorganized extracellular matrix proteins in the media of the neonatal aorta. Our results suggest that BC1 is a suppressor of SMC differentiation during vascular development. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Transverse Energy in nucleus-nucleus collisions: A review

International Nuclear Information System (INIS)

Tincknell, M.

1988-01-01

The status of Transverse Energy (E/sub T/) in relativistic nucleus-nucleus collisions at the Brookhaven AGS and the CERN SPS is reviewed. The definition of E/sub T/ and its physical significance are discussed. The basic techniques and limitations of the experimental measurements are presented. The acceptances of the major experiments to be discussed are shown, along with remarks about their idiosyncrasies. The data demonstrate that the nuclear geometry of colliding spheres primarily determines the shapes of the observed spectra. Careful account of the acceptances is crucial to comparing and interpreting results. It is concluded that nuclear stopping power is high, and that the amount of energy deposited into the interaction volume is increasing with beam energy even at SPS energies. The energy densities believed to be obtained at the SPS are close to the critical values predicted for the onset of a quark-gluon plasma. 25 refs., 8 figs

CART neurons in the arcuate nucleus and lateral hypothalamic area exert differential controls on energy homeostasis

Directory of Open Access Journals (Sweden)

Jackie Lau

2018-01-01

Full Text Available Objective: The cocaine- and amphetamine-regulated transcript (CART codes for a pivotal neuropeptide important in the control of appetite and energy homeostasis. However, limited understanding exists for the defined effector sites underlying CART function, as discrepant effects of central CART administration have been reported. Methods: By combining Cart-cre knock-in mice with a Cart adeno-associated viral vector designed using the flip-excision switch (AAV-FLEX technology, specific reintroduction or overexpression of CART selectively in CART neurons in the arcuate nucleus (Arc and lateral hypothalamic area (LHA, respectively, was achieved. The effects on energy homeostasis control were investigated. Results: Here we show that CART neuron-specific reintroduction of CART into the Arc and LHA leads to distinct effects on energy homeostasis control. Specifically, CART reintroduction into the Arc of otherwise CART-deficient Cartcre/cre mice markedly decreased fat mass and body weight, whereas CART reintroduction into the LHA caused significant fat mass gain and lean mass loss, but overall unaltered body weight. The reduced adiposity in ArcCART;Cartcre/cre mice was associated with an increase in both energy expenditure and physical activity, along with significantly decreased Npy mRNA levels in the Arc but with no change in food consumption. Distinctively, the elevated fat mass in LHACART;Cartcre/cre mice was accompanied by diminished insulin responsiveness and glucose tolerance, greater spontaneous food intake, and reduced energy expenditure, which is consistent with the observed decrease of brown adipose tissue temperature. This is also in line with significantly reduced tyrosine hydroxylase (Th and notably increased corticotropin-releasing hormone (Crh mRNA expressions in the paraventricular nucleus (PVN. Conclusions: Taken together, these results identify catabolic and anabolic effects of CART in the Arc and LHA, respectively, demonstrating for

Selective alterations of NMDAR function and plasticity in D1 and D2 medium spiny neurons in the nucleus accumbens shell following chronic intermittent ethanol exposure.

Science.gov (United States)

Renteria, Rafael; Maier, Esther Y; Buske, Tavanna R; Morrisett, Richard A

2017-01-01

A major mouse model widely adopted in recent years to induce pronounced ethanol intake is the ethanol vapor model known as "CIE" or "Chronic Intermittent Ethanol." One critical question concerning this model is whether the rapid induction of high blood ethanol levels for such short time periods is sufficient to induce alterations in N-methyl-d-aspartate receptor (NMDAR) function which may contribute to excessive ethanol intake. In this study, we determined whether such short term intermittent ethanol exposure modulates NMDAR function as well as other prominent electrophysiological properties and the expression of plasticity in both D1 (D1+) and D2 (D1-) dopamine receptor expressing medium spiny neurons (MSNs) in the nucleus accumbens (NAc) shell. To distinguish between the two subtypes of MSNs in the NAc we treated Drd1a-TdTomato transgenic mice with CIE vapor and electrophysiological recordings were conducted 24 h after the last vapor exposure. To investigate CIE induced alterations in plasticity, long-term depression (LTD) was induced by pairing low frequency stimulation (LFS) with post synaptic depolarization. In ethanol naïve mice, LFS induced synaptic depression (LTD) was apparent exclusively in D1+ MSNs. Whereas in slices prepared from CIE treated mice, LFS induced synaptic potentiation (LTP) in D1+ MSNs. Furthermore, following CIE exposure, LFS now produced LTD in D1- MSNs. We found that CIE exposure induced an increase in excitability in D1+ MSNs with no change in D1- MSNs. After CIE, we found a significant increase in spontaneous EPSCs (sEPSCs) frequency in D1+ but not D1- MSNs suggesting alterations in baseline α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) mediated signaling. CIE induced changes in NMDAR function were measured using the NMDA/AMPA ratio and input-output curves of isolated NMDAR currents. We observed a significant increase in NMDAR function in D1+ MSNs and a decrease in D1- MSNs after ethanol vapor exposure. The

Aspects of Coulomb dissociation and interference in peripheral nucleus-nucleus collisions

International Nuclear Information System (INIS)

Nystrand, Joakim; Baltz, Anthony; Klein, Spencer R.

2001-01-01

Coherent vector meson production in peripheral nucleus-nucleus collisions is discussed. These interactions may occur for impact parameters much larger than the sum of the nuclear radii. Since the vector meson production is always localized to one of the nuclei, the system acts as a two-source interferometer in the transverse plane. By tagging the outgoing nuclei for Coulomb dissociation it is possible to obtain a measure of the impact parameter and thus the source separation in the interferometer. This is of particular interest since the life-time of the vector mesons are generally much shorter than the impact parameters of the collisions

Neutrino-nucleus collision at intermediate energy

International Nuclear Information System (INIS)

Kosmas, T.S.; Oset, E.

1999-01-01

Neutrino-nucleus reactions at low and intermediate energy up to E ν = 500 MeV are studied for the most interesting nuclei from an experimental point of view. We focus on neutrino-nucleus cross-sections of semi-inclusive processes, for which recent measurements from radiochemical experiments at LAMPF and KARMEN laboratories are available. The method employed uses the modified Lindhard function for the description of the particle-hole excitations of the final nucleus via a local density approximation. (authors)

Transverse and radial flow in intermediate energy nucleus-nucleus collisions

International Nuclear Information System (INIS)

Vestfall, D. Gary

1997-01-01

We have studied transverse and radial flow in nucleus-nucleus collisions ranging in energy from 15 to 155 MeV/nucleon. We have measured the impact parameter dependence of the balance energy for Ar + Sc and compared the results with Quantum Molecular Dynamics calculations with and without momentum dependence. We have shown that transverse flow and the balance energy dependence on the isospin of the system using the systems 58 Fe + 58 Fe, 58 Ni + 58 Ni, and 58 Mn + 58 Fe. These results are compared with Boltzmann-Uehling-Uehlenbeck calculations incorporating isospin-dependence. We have measured radial flow for Ar + Sc and find that about 50% of the observed energy is related to radial flow. (author)

Nuclear energy release in hadron-nucleus collisions

International Nuclear Information System (INIS)

Strugalski, Z.; Strugalska-Gola, E.

1998-01-01

Energy release process in nuclear reactions induced by fast hadrons in hadron-nucleus collisions is discussed. Some portion of the internal nuclear energy is released when the locally damaged in a collision, and instable therefore, residual target nucleus transits itself into light nuclear fragments (nucleons, D, T) and a stable lighter final nucleus or some number of stable lighter nuclei. It is not excluded that in some of the collisions the induced intranuclear nuclear reactions may be energy overcompensating. Corresponding reconnaissance should be made - in analysing the nuclear reactions induced in hadron-nucleus collisions

Thermal Bremsstrahlung probing nuclear multifragmentation in nucleus-nucleus collisions around the Fermi energy

International Nuclear Information System (INIS)

D'Enterria, D.G.

2000-05-01

The thermodynamical properties of nuclear matter at moderate temperatures and densities, in the vicinity of the predicted nuclear liquid-gas phase transition, are studied using as experimental probe the hard-photons (E γ > 30 MeV) emitted in nucleus-nucleus collisions. Photon and charged-particle production in four different heavy-ion reactions (Ar 36 + Au 197 , Ag 107 , Ni 58 , C 12 at 60 A*MeV) is measured exclusively and inclusively coupling the TAPS photon spectrometer with two charged-particle and intermediate-mass-fragment detectors covering nearly 4π. We confirm that Bremsstrahlung emission in first-chance (off-equilibrium) proton-neutron collisions (pnγ) is the dominant origin of hard photons. We also firmly establish the existence of a thermal radiation component emitted in second-chance proton-neutron collisions. This thermal Bremsstrahlung emission takes place in semi-central and central nucleus-nucleus reactions involving heavy targets. We exploit this observation i) to demonstrate that thermal equilibrium is reached during the reaction, ii) to establish a new thermometer of nuclear matter based on Bremsstrahlung photons, iii) to derive the thermodynamical properties of the excited nuclear sources and, in particular, to establish a 'caloric curve' (temperature versus excitation energy), and iv) to assess the time-scales of the nuclear break-up process. (author)

Nucleon molecular orbitals and the transition mechanism between molecular orbitals in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Imanishi, B.; Misono, S.; von Oertzen, W.; Voit, H.

1988-08-01

The molecular orbitals of the nucleon(s) in nucleus-nucleus collisions are dynamically defined as a linear combination of nucleon single-particle orbits (LCNO) in a rotating frame by using the coupled-reaction-channel (CRC) theory. Nucleon molecular orbitals and the promotions of nucleon, - especially due to the Landau-Zener radial coupling are discussed with the method above mentioned. (author)

Differential gene regulation of GHSR signaling pathway in the arcuate nucleus and NPY neurons by fasting, diet-induced obesity, and 17β-estradiol.

Science.gov (United States)

Yasrebi, Ali; Hsieh, Anna; Mamounis, Kyle J; Krumm, Elizabeth A; Yang, Jennifer A; Magby, Jason; Hu, Pu; Roepke, Troy A

2016-02-15

Ghrelin's receptor, growth hormone secretagogue receptor (GHSR), is highly expressed in the arcuate nucleus (ARC) and in neuropeptide Y (NPY) neurons. Fasting, diet-induced obesity (DIO), and 17β-estradiol (E2) influence ARC Ghsr expression. It is unknown if these effects occur in NPY neurons. Therefore, we examined the expression of Npy, Agrp, and GHSR signaling pathway genes after fasting, DIO, and E2 replacement in ARC and pools of NPY neurons. In males, fasting increased ARC Ghsr and NPY Foxo1 but decreased NPY Ucp2. In males, DIO decreased ARC and NPY Ghsr and Cpt1c. In fed females, E2 increased Agrp, Ghsr, Cpt1c, and Foxo1 in ARC. In NPY pools, E2 decreased Foxo1 in fed females but increased Foxo1 in fasted females. DIO in females suppressed Agrp and augmented Cpt1c in NPY neurons. In summary, genes involved in GHSR signaling are differentially regulated between the ARC and NPY neurons in a sex-dependent manner. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Differential gene regulation of GHSR signaling pathway in the arcuate nucleus and NPY neurons by fasting, diet-induced obesity, and 17β-estradiol

Science.gov (United States)

Yasrebi, Ali; Hsieh, Anna; Mamounis, Kyle J.; Krumm, Elizabeth A.; Yang, Jennifer A.; Magby, Jason; Hu, Pu; Roepke, Troy A.

2015-01-01

Ghrelin’s receptor, growth hormone secretagogue receptor (GHSR), is highly expressed in the arcuate nucleus (ARC) and in neuropeptide Y (NPY) neurons. Fasting, diet-induced obesity (DIO), and 17β-estradiol (E2) influence ARC Ghsr expression. It is unknown if these effects occur in NPY neurons. Therefore, we examined the expression of Npy, Agrp, and GHSR signaling pathway genes after fasting, DIO, and E2 replacement in ARC and pools of NPY neurons. In males, fasting increased ARC Ghsr and NPY Foxo1 but decreased NPY Ucp2. In males, DIO decreased ARC and NPY Ghsr and Cpt1c. In fed females, E2 increased Agrp, Ghsr, Cpt1c, and Foxo1 in ARC. In NPY pools, E2 decreased Foxo1 in fed females but increased Foxo1 in fasted females. DIO in females suppressed Agrp and augmented Cpt1c in NPY neurons. In summary, genes involved in GHSR signaling are differentially regulated between the ARC and NPY neurons in a sex-dependent manner. PMID:26577678

Transverse-momentum distribution of produced particles in ultrarelativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Ban-Hao, S.; Wong, C.

1985-01-01

In order to discern coherent or collective processes from incoherent processes in nucleus-nucleus reactions at high energies, we study the transverse-momentum distribution of the produced particles with an incoherent-multiple-collision model. In this model, the projectile nucleon makes successive inelastic collisions with nucleons in the target nucleus, the probability of such collisions being given by the thickness function and the nucleon-nucleon inelastic cross section. It is assumed that each baryon-baryon collision produces particles and degrades momenta just as a baryon-baryon collision in free space, and that there are no secondary collisions between the produced particles and the nucleons. We found that the average transverse momentum and the charged-multiplicity data at Fermilab and CERN ISR energies can be well explained by such a model. However, the average transverse momentum for some events observed by the Japanese-American cooperative emulsion experiment (JACEE) associated with large energy density in the central rapidity region differ markedly from the model results. Such a deviation indicates the presence of coherent or collective effects for these collisions and may indicate the possibility of a formation of quark-gluon plasma

Fast detector for triggering on charged particle multiplicity for relativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Agakishiev, G.; Man'yakov, P.K.; Drees, A.

1997-01-01

The simple and fast detector of charged particle multiplicity for relativistic nucleus-nucleus collision studies is performed. The multiplicity detector has been designed for the first level trigger of the CERES/NA45 experiment to study Pb-Au collisions at CERN SPS energies. The detector has allowed a realization of the 40 ns trigger for selection of events with definite impact parameter. The construction, operation characteristics, method of calibration, and testing results are described in detail

Red nucleus and rubrospinal tract disorganization in the absence of Pou4f1

Science.gov (United States)

Martinez-Lopez, Jesus E.; Moreno-Bravo, Juan A.; Madrigal, M. Pilar; Martinez, Salvador; Puelles, Eduardo

2015-01-01

The red nucleus (RN) is a neuronal population that plays an important role in forelimb motor control and locomotion. Histologically it is subdivided into two subpopulations, the parvocellular RN (pRN) located in the diencephalon and the magnocellular RN (mRN) in the mesencephalon. The RN integrates signals from motor cortex and cerebellum and projects to spinal cord interneurons and motor neurons through the rubrospinal tract (RST). Pou4f1 is a transcription factor highly expressed in this nucleus that has been related to its specification. Here we profoundly analyzed consequences of Pou4f1 loss-of-function in development, maturation and axonal projection of the RN. Surprisingly, RN neurons are specified and maintained in the mutant, no cell death was detected. Nevertheless, the nucleus appeared disorganized with a strong delay in radial migration and with a wider neuronal distribution; the neurons did not form a compacted population as they do in controls, Robo1 and Slit2 were miss-expressed. Cplx1 and Npas1, expressed in the RN, are transcription factors involved in neurotransmitter release, neuronal maturation and motor function processes among others. In our mutant mice, both transcription factors are lost, suggesting an abnormal maturation of the RN. The resulting altered nucleus occupied a wider territory. Finally, we examined RST development and found that the RN neurons were able to project to the spinal cord but their axons appeared defasciculated. These data suggest that Pou4f1 is necessary for the maturation of RN neurons but not for their specification and maintenance. PMID:25698939

Electromagnetic processes in nucleus-nucleus collisions relating to space radiation research

Science.gov (United States)

Norbury, John W.

1992-01-01

Most of the papers within this report deal with electromagnetic processes in nucleus-nucleus collisions which are of concern in the space radiation program. In particular, the removal of one and two nucleons via both electromagnetic and strong interaction processes has been extensively investigated. The theory of relativistic Coulomb fission has also been developed. Several papers on quark models also appear. Finally, note that the theoretical methods developed in this work have been directly applied to the task of radiation protection of astronauts. This has been done by parameterizing the theoretical formalism in such a fashion that it can be used in cosmic ray transport codes.

Contribution estimate of the 2+(1.78 MeV) level excitation in silicon nucleus to the cross section of the 28Si(π, 3π)28Si * reaction

International Nuclear Information System (INIS)

Ermekov, N.T.; Korotkikh, V.L.; Starkov, N.I.

1981-01-01

For the purpose of studying the channel contribution with low-lying level excitation in silicon nucleus into the differential cross section of the reaction the π - + 28 Si→π - +π - +π + + 28 Si reaction is investigated at the bombarding 16 GeV/c pion momentum. The calculation of differential cross sections on the basis of the Glauber model with a factorizing nucleus density is performed. The found parameters of nuclear densities are tabulated. The investigated reaction differential cross sections are calculated with account of coherent production as well as the channel with 2 + (1.78 MeV) level excitation. The calculated differential cross sections values integrated by the effective mass of the produced three-pion system (0.9 GeV + , 1.78 MeV)=0.25 mb are obtained. It is shown that filling the diffraction minimum in three-pion production differential cross section for ''alive'' silicon target is due to contribution from events with the excitation of the low-lying level 2 + (1.78 MeV) [ru

Chronic intermittent ethanol exposure and withdrawal leads to adaptations in nucleus accumbens core postsynaptic density proteome and dendritic spines.

Science.gov (United States)

Uys, Joachim D; McGuier, Natalie S; Gass, Justin T; Griffin, William C; Ball, Lauren E; Mulholland, Patrick J

2016-05-01

Alcohol use disorder is a chronic relapsing brain disease characterized by the loss of ability to control alcohol (ethanol) intake despite knowledge of detrimental health or personal consequences. Clinical and pre-clinical models provide strong evidence for chronic ethanol-associated alterations in glutamatergic signaling and impaired synaptic plasticity in the nucleus accumbens (NAc). However, the neural mechanisms that contribute to aberrant glutamatergic signaling in ethanol-dependent individuals in this critical brain structure remain unknown. Using an unbiased proteomic approach, we investigated the effects of chronic intermittent ethanol (CIE) exposure on neuroadaptations in postsynaptic density (PSD)-enriched proteins in the NAc of ethanol-dependent mice. Compared with controls, CIE exposure significantly changed expression levels of 50 proteins in the PSD-enriched fraction. Systems biology and functional annotation analyses demonstrated that the dysregulated proteins are expressed at tetrapartite synapses and critically regulate cellular morphology. To confirm this latter finding, the density and morphology of dendritic spines were examined in the NAc core of ethanol-dependent mice. We found that CIE exposure and withdrawal differentially altered dendrite diameter and dendritic spine density and morphology. Through the use of quantitative proteomics and functional annotation, these series of experiments demonstrate that ethanol dependence produces neuroadaptations in proteins that modify dendritic spine morphology. In addition, these studies identified novel PSD-related proteins that contribute to the neurobiological mechanisms of ethanol dependence that drive maladaptive structural plasticity of NAc neurons. © 2015 Society for the Study of Addiction.

Differential proteomics study of platelets in asymptomatic constitutional macrothrombocytopenia: altered levels of cytoskeletal proteins.

Science.gov (United States)

Karmakar, Shilpita; Saha, Sutapa; Banerjee, Debasis; Chakrabarti, Abhijit

2015-01-01

Harris platelet syndrome (HPS), also known as asymptomatic constitutional macrothrombocytopenia (ACMT), is an autosomal dominant platelet disorder characterized by mild-to-severe thrombocytopenia and giant platelets with normal platelet aggregation and absence of bleeding symptoms. We have attempted a comparative proteomics study for profiling of platelet proteins in healthy vs. pathological states to discover characteristic protein expression changes in macrothrombocytes and decipher the factors responsible for the functionally active yet morphologically distinct platelets. We have used 2-D gel-based protein separation techniques coupled with MALDI-ToF/ToF-based mass spectrometric identification and characterization of the proteins to investigate the differential proteome profiling of platelet proteins isolated from the peripheral blood samples of patients and normal volunteers. Our study revealed altered levels of actin-binding proteins such as myosin light chain, coactosin-like protein, actin-related protein 2/3 complex, and transgelin2 that hint toward the cytoskeletal changes necessary to maintain the structural and functional integrity of macrothrombocytes. We have also observed over expressed levels of peroxiredoxin2 that signifies the prevailing oxidative stress in these cells. Additionally, altered levels of protein disulfide isomerase and transthyretin provide insights into the measures adapted by the macrothrombocytes to maintain their normal functional activity. This first proteomics study of platelets from ACMT may provide an understanding of the structural stability and normal functioning of these platelets in spite of their large size. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Nuclear Mechanics and Stem Cell Differentiation.

Science.gov (United States)

Mao, Xinjian; Gavara, Nuria; Song, Guanbin

2015-12-01

Stem cells are characterized by their self-renewal and multi-lineage differentiation potential. Stem cell differentiation is a prerequisite for the application of stem cells in regenerative medicine and clinical therapy. In addition to chemical stimulation, mechanical cues play a significant role in regulating stem cell differentiation. The integrity of mechanical sensors is necessary for the ability of cells to respond to mechanical signals. The nucleus, the largest and stiffest cellular organelle, interacts with the cytoskeleton as a key mediator of cell mechanics. Nuclear mechanics are involved in the complicated interactions of lamins, chromatin and nucleoskeleton-related proteins. Thus, stem cell differentiation is intimately associated with nuclear mechanics due to its indispensable role in mechanotransduction and mechanical response. This paper reviews several main contributions of nuclear mechanics, highlights the hallmarks of the nuclear mechanics of stem cells, and provides insight into the relationship between nuclear mechanics and stem cell differentiation, which may guide clinical applications in the future.

Altered sensitivity to ellagic acid in neuroblastoma cells undergoing differentiation with 12-O-tetradecanoylphorbol-13-acetate and all-trans retinoic acid.

Science.gov (United States)

Alfredsson, Christina Fjæraa; Rendel, Filip; Liang, Qui-Li; Sundström, Birgitta E; Nånberg, Eewa

2015-12-01

Ellagic acid has previously been reported to induce reduced proliferation and activation of apoptosis in several tumor cell lines including our own previous data from non-differentiated human neuroblastoma SH-SY5Y cells. The aim of this study was now to investigate if in vitro differentiation with the phorbol ester 12-O- tetradecanoylphorbol-13-acetate or the vitamin A derivative all-trans retinoic acid altered the sensitivity to ellagic acid in SH-SY5Y cells. The methods used were cell counting and LDH-assay for evaluation of cell number and cell death, flow cytometric analysis of SubG1- and TUNEL-analysis for apoptosis and western blot for expression of apoptosis-associated proteins. In vitro differentiation was shown to reduce the sensitivity to ellagic acid with respect to cell detachment, loss of viability and activation of apoptosis. The protective effect was phenotype-specific and most prominent in all-trans retinoic acid-differentiated cultures. Differentiation-dependent up-regulation of Bcl-2 and integrin expression is introduced as possible protective mechanisms. The presented data also point to a positive correlation between proliferative activity and sensitivity to ellagic-acid-induced cell detachment. In conclusion, the presented data emphasize the need to consider degree of neuronal differentiation and phenotype of neuroblastoma cells when discussing a potential pharmaceutical application of ellagic acid in tumor treatment. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Model of homogeneous nucleus. Total and inelastic cross sections of nucleon-nucleus scattering

International Nuclear Information System (INIS)

Ponomarev, L.A.; Smorodinskaya, N.Ya.

1985-01-01

It is shown that the nucleon-nuckleus scattering amplitude at high energy can be easily calculated by generalization of the nucleon-nucleon scattering amplitude and satisfies a simple factorization relation. As distinct from the Glauber model, the suggested approach makes no use of the nucleonic structure of the nucleus and the hadron-nucleus scattering amplitude is not expressed in terms of hadron-nucleon scattering amplitudes. The energy dependence of total and inelastic cross sections is successfully described for a number of nuclei

Interesting correlations among various parameters of charged secondaries in nucleus - nucleus interactions at 4.5 A GeV

International Nuclear Information System (INIS)

Khan, M. Saleem; Shukla, Praveen Prakash; Khushnood, H.

2015-01-01

The study of the characteristic of charged secondaries was the aim of most of the experiments on high energy nucleon-nucleon and nucleus-nucleus collisions. Investigation are carried out on the produced secondary charged particles with a common belief that these particles are more informative about the collisional dynamics and thus, could be effective in revealing the underlying physics of high energy relativistic interactions. So for understanding the mechanism of multiparticle production in high energy hadron-nucleus collisions, the correlations amongst the secondary charged particles are studied. Several workers have attempted to study the multiplicity correlations over widely different incident energies with different projectiles. The AALMT collaboration have also studied the multiplicity correlations in 200 GeV proton-nucleus collisions

Prenatal nicotine is associated with reduced AMPA and NMDA receptor-mediated rises in calcium within the laterodorsal tegmentum: a pontine nucleus involved in addiction processes

DEFF Research Database (Denmark)

Mc Nair, Laura Kristine Frendrup; Kohlmeier, Kristi Anne

2015-01-01

excitatory neurotransmitter within the laterodorsal tegmental nucleus (LDT), which is a brainstem region importantly involved in responding to motivational stimuli and critical in development of drug addiction-associated behaviours, however, it is unknown whether PNE alters glutamate signalling within...

Microtubules move the nucleus to quiescence.

Science.gov (United States)

Laporte, Damien; Sagot, Isabelle

2014-01-01

The nucleus is a cellular compartment that hosts several macro-molecular machines displaying a highly complex spatial organization. This tight architectural orchestration determines not only DNA replication and repair but also regulates gene expression. In budding yeast microtubules play a key role in structuring the nucleus since they condition the Rabl arrangement in G1 and chromosome partitioning during mitosis through their attachment to centromeres via the kinetochore proteins. Recently, we have shown that upon quiescence entry, intranuclear microtubules emanating from the spindle pole body elongate to form a highly stable bundle that spans the entire nucleus. Here, we examine some molecular mechanisms that may underlie the formation of this structure. As the intranuclear microtubule bundle causes a profound re-organization of the yeast nucleus and is required for cell survival during quiescence, we discuss the possibility that the assembly of such a structure participates in quiescence establishment.

High energy nucleus-nucleus collisions at CERN: Signatures, physical observables and experimental results

International Nuclear Information System (INIS)

Harris, J.W.

1988-02-01

Experimental results on high energy nucleus-nucleus collisions have become available with the recent experiments at CERN utilizing 200 GeV/n oxygen and sulfur beams. Physics motivations for these experiments are presented: a description of predicted signatures for possible formation of a quark-gluon plasma and physical observables that are expected to provide important information for understanding the dynamics of these collisions. A presentation will be made of some of the first experimental results to emerge from this new field. 28 refs., 9 figs

The isospin dependence of the nucleus-nucleus inelastic cross-section at high energy

International Nuclear Information System (INIS)

Rashdan, M.; Farhan, A.M.; Hassib, E.; Kareem, W. Abdel

2006-01-01

The isospin dependence of the nucleus-nucleus inelastic cross-section at high energy is investigated within the multiple scattering theory. The multiple integrals are evaluated by Monte Carlo method as well as by the optical limit approximation of the Glauber model. Calculations are performed for 14-23 N, 16-24 O and 18-26 F isotopes colliding with carbon target around 1 GeV. It is found that rms radii and the density distributions show a halo structure of 22 N, 23 O and 24 F

Strangeness and charm production in nucleus-nucleus collisions at beam energies near the thresholds

International Nuclear Information System (INIS)

Senger, P.

2001-01-01

The creation of strangeness and charm in nucleus-nucleus collisions at threshold beam energies is discussed as a probe for compressed baryonic matter. Experimental data on strangeness production at SIS energies indicate that the properties of kaons and antikaons are modified in the dense nuclear medium. An experiment is proposed to explore the QCD phase diagram in the region of highest baryon densities. An important observable will be charm production close to threshold. (orig.)

Single-prolonged stress induces apoptosis in dorsal raphe nucleus in the rat model of posttraumatic stress disorder

Directory of Open Access Journals (Sweden)

Liu Dongjuan

2012-11-01

Full Text Available Abstract Introduction Post-traumatic stress disorder (PTSD is an anxiety disorder that develops after exposure to a life-threatening traumatic experience. Meta-analyses of the brainstem showed that midsagittal area of the pons was significantly reduced in patients with PTSD, suggesting a potential apoptosis in dorsal raphe nucleus after single-prolonged stress (SPS. The aim of this study is to investigate whether SPS induces apoptosis in dorsal raphe nucleus in PTSD rats, which may be a possible mechanism of reduced volume of pons and density of gray matter. Methods In this study, rats were randomly divided into 1d, 7d and 14d groups after SPS along with the control group. The apoptosis rate was determined using annexin V-FITC/PI double-labeled flow cytometry (FCM. Levels of Cytochrome c (Cyt-C was examined by Western blotting. Expression of Cyt-C on mitochondria in the dorsal raphe nucleus neuron was determined by enzymohistochemistry under transmission electron microscopy (TEM. The change of thiamine monophosphatase (TMP levels was assessed by enzymohistochemistry under light microscope and TEM. Morphological changes of the ultrastructure of the dorsal raphe nucleus neuron were determined by TEM. Results Apoptotic morphological alterations were observed in dorsal raphe nucleus neuron for all SPS-stimulate groups of rats. The apoptosis rates were significantly increased in dorsal raphe nucleus neuron of SPS rats, along with increased release of cytochrome c from the mitochondria into the cytoplasm, increased expression of Cyt-C and TMP levels in the cytoplasm, which reached to the peak of increase 7 days of SPS. Conclusions The results indicate that SPS induced Cyt-C released from mitochondria into cytosol and apoptosis in dorsal raphe nucleus neuron of rats. Increased TMP in cytoplasm facilitated the clearance of apoptotic cells. We propose that this presents one of the mechanisms that lead to reduced volume of pons and gray matter associated

Oestradiol and progesterone differentially alter cytoskeletal protein expression and flame cell morphology in Taenia crassiceps.

Science.gov (United States)

Ambrosio, Javier R; Ostoa-Saloma, Pedro; Palacios-Arreola, M Isabel; Ruíz-Rosado, Azucena; Sánchez-Orellana, Pedro L; Reynoso-Ducoing, Olivia; Nava-Castro, Karen E; Martínez-Velázquez, Nancy; Escobedo, Galileo; Ibarra-Coronado, Elizabeth G; Valverde-Islas, Laura; Morales-Montor, Jorge

2014-09-01

We examined the effects of oestradiol (E2) and progesterone (P4) on cytoskeletal protein expression in the helminth Taenia crassiceps - specifically actin, tubulin and myosin. These proteins assemble into flame cells, which constitute the parasite excretory system. Total protein extracts were obtained from E2- and P4-treated T. crassiceps cysticerci and untreated controls, and analysed by one- and two-dimensional protein electrophoresis, flow cytometry, immunofluorescence and videomicroscopy. Exposure of T. crassiceps cysticerci to E2 and P4 induced differential protein expression patterns compared with untreated controls. Changes in actin, tubulin and myosin expression were confirmed by flow cytometry of parasite cells and immunofluorescence. In addition, parasite morphology was altered in response to E2 and P4 versus controls. Flame cells were primarily affected at the level of the ciliary tuft, in association with the changes in actin, tubulin and myosin. We conclude that oestradiol and progesterone act directly on T. crassiceps cysticerci, altering actin, tubulin and myosin expression and thus affecting the assembly and function of flame cells. Our results increase our understanding of several aspects of the molecular crosstalk between host and parasite, which might be useful in designing anthelmintic drugs that exclusively impair parasitic proteins which mediate cell signaling and pathogenic reproduction and establishment. Copyright © 2014 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Anti p-nucleus interaction

International Nuclear Information System (INIS)

Peng, J.C.

1986-05-01

Status and future prospects of antiproton-nucleus scattering experiments are presented. These scattering experiments were conducted at antiproton beam momentums of 300 and 600 MeV/c on target nuclei of 6 Li, 12 C, 16 O, 18 O, 40 Ca, 48 Ca, and 208 Pb. Antiproton-proton reactions investigated antiproton-nucleus bound or resonant states in antiproton reactions with d, 6 Li, 12 C, 63 Cu, and 209 Bi. Inelastic scattering experiments investigated the spin-isospin dependence of the NN interactions. 19 refs., 1 fig., 1 tab

Hadron-nucleus interactions with a small target-nucleus excitation

International Nuclear Information System (INIS)

Anzon, Z.V.; Chasnikov, I.Ya.; Shakhova, Ts.I.

1981-01-01

Hadron inelastic interactions in nuclear emulsion with a small target-nucleus excitation in the energy range 7.5-200 GeV have been studied. Possible reasons for the differences in production cross-section for events with even and odd number of S-particles are analysed

Formation, structure, and evolution of boiling nucleus and interfacial tension between bulk liquid phase and nucleus

Science.gov (United States)

Wang, Xiao-Dong; Peng, Xiao-Feng; Tian, Yong; Wang, Bu-Xuan

2005-05-01

In this paper, the concept of the molecular free path is introduced to derive a criterion distinguishing active molecules from inactive molecules in liquid phase. A concept of the critical aggregation concentration (CAC) of active molecules is proposed to describe the physical configuration before the formation of a nucleus during vapor-liquid phase transition. All active molecules exist as monomers when the concentration of active molecules is lower than CAC, while the active molecules will generate aggregation once the concentration of the active molecules reaches CAC. However, these aggregates with aggregation number, N, smaller than five can steadily exist in bulk phase. The other excess active molecules can only produce infinite aggregation and form a critical nucleus of vapor-liquid phase transition. Without any outer perturbation the state point of CAC corresponds to the critical superheated or supercooled state. Meanwhile, a model of two-region structure of a nucleus is proposed to describe nucleus evolution. The interfacial tension between bulk liquid phase and nucleus is dependent of the density gradient in the transition region and varies with the structure change of the transition region. With the interfacial tension calculated using this model, the predicted nucleation rate is very close to the experimental measurement. Furthermore, this model and associated analysis provides solid theoretical evidences to clarify the definition of nucleation rate and understand nucleation phenomenon with the insight into the physical nature.

On the possible detection of quantum-mechanical interferences between gravitational forces and nucleus-nucleus Coulomb forces

International Nuclear Information System (INIS)

Silveira, R. da

1996-07-01

Possible effects of quantum-mechanical interferences between gravitational forces and the nucleus-nucleus Coulomb interaction are discussed. It is shown that, although very small, these effects could be measured using low energy scattering between identical heavy nuclei, e.g. for the system 208 Pb + 208 Pb (E L = 5 MeV). (author)

Dynamics of hadron-nucleus interactions

International Nuclear Information System (INIS)

Wallace, S.J.

1981-07-01

Recent progress in diffraction theory shows that proton-nucleus scattering at nonforward angles is dominated by the interference of waves from two or more bright spots. Analytic formulas based on asymptotic theories of diffraction yield valuable new insights into the scattering and these formulas can be readily extended to illuminate the role of dynamical ingredients, i.e., the nucleon-nucleon amplitudes. The governing parameters of the diffraction and some direct connections between the observed cross sections and the input dynamics are reviewed. New information regarding the nucleon-nucleon parameters based on recent phase shift analyses show some systematic differences from the effective NN amplitudes which produce fits to proton-nucleus diffraction data. Recent progress in understanding the role of Δ-isobars in proton-nucleus dynamics is reviewed. 126 references

Control of differentiation of melanoma cells

International Nuclear Information System (INIS)

Eguchi, Goro

1980-01-01

To develop the method to induce the appearance of differentiation in amelanotic melanoma, experimental control of differentiation in B-16 melanoma cells of mice was discussed. Human melanoma cells and yellow melanin pigment cells useful for a fundamental study of radiotherapy for cancer were cultured and were differentiated into some lines. Melanotic B-16 cells and amelanotic B-16 cells were irradiated with thermal neutron (neutron: 2.7 x 10 12 , γ-dose: 32.3 rad) after they were cultured in culture solution containing 10 γ/ml of 10 B-dopa for 13 hours. A fine structure 5 hours after the irradiation in one of 5 experimental cases showed aggregated disintegration of melanin pigment particles, markedly deformed and fragmentized nucleus, and structural changes in cell membrane. (Tsunoda, M.)

Transport of glutathione into the nucleus.

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Queval, Guillaume; Foyer, Christine

2014-10-01

The tripeptide thiol glutathione (GSH) is present in the nucleus of plant and animal cells. However, the functions of GSH in the nucleus remain poorly characterised. GSH appears to become sequestered in the nucleus at the early stages of the cell cycle. As part of our search for proteins that may be involved in GSH transport into the nucleus, we studied the functions of the nucleoporin called Alacrima Achalasia aDrenal Insufficiency Neurologic disorder (ALADIN). ALADIN is encoded by the Achalasia-Addisonianism-Alacrimia (AAAS) gene in mammalian cells. Defects in ALADIN promote adrenal disorders and lead to the triple A syndrome in humans. The ALADIN protein localizes to the nuclear envelope in Arabidopsis thaliana and interacts with other components of the nuclear pore complex (NPC). We characterised the functions of the ALADIN protein in an Arabidopsis thaliana T-DNA insertion knockout mutant, which shows slow growth compared to the wild type. Copyright © 2014. Published by Elsevier Inc.

γ-Secretase modulators reduce endogenous amyloid β42 levels in human neural progenitor cells without altering neuronal differentiation

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D’Avanzo, Carla; Sliwinski, Christopher; Wagner, Steven L.; Tanzi, Rudolph E.; Kim, Doo Yeon; Kovacs, Dora M.

2015-01-01

Soluble γ-secretase modulators (SGSMs) selectively decrease toxic amyloid β (Aβ) peptides (Aβ42). However, their effect on the physiologic functions of γ-secretase has not been tested in human model systems. γ-Secretase regulates fate determination of neural progenitor cells. Thus, we studied the impact of SGSMs on the neuronal differentiation of ReNcell VM (ReN) human neural progenitor cells (hNPCs). Quantitative PCR analysis showed that treatment of neurosphere-like ReN cell aggregate cultures with γ-secretase inhibitors (GSIs), but not SGSMs, induced a 2- to 4-fold increase in the expression of the neuronal markers Tuj1 and doublecortin. GSI treatment also induced neuronal marker protein expression, as shown by Western blot analysis. In the same conditions, SGSM treatment selectively reduced endogenous Aβ42 levels by ∼80%. Mechanistically, we found that Notch target gene expressions were selectively inhibited by a GSI, not by SGSM treatment. We can assert, for the first time, that SGSMs do not affect the neuronal differentiation of hNPCs while selectively decreasing endogenous Aβ42 levels in the same conditions. Our results suggest that our hNPC differentiation system can serve as a useful model to test the impact of GSIs and SGSMs on both endogenous Aβ levels and γ-secretase physiologic functions including endogenous Notch signaling.—D’Avanzo, C., Sliwinski, C., Wagner, S. L., Tanzi, R. E., Kim, D. Y., Kovacs, D. M. γ-Secretase modulators reduce endogenous amyloid β42 levels in human neural progenitor cells without altering neuronal differentiation. PMID:25903103

Nucleus management with irrigating vectis

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Srinivasan Aravind

2009-01-01

Full Text Available The main objective in modern cataract surgery is to achieve a better unaided visual acuity with rapid post-surgical recovery and minimal surgery-related complications. Early visual rehabilitation and better unaided vision can be achieved only by reducing the incision size. In manual small incision cataract surgery (MSICS, incision is between 5.5 to 7 mm. Once the nucleus is prolapsed into the anterior chamber, it can be extracted through the tunnel. Nucleus extraction with an irrigating vectis is a very simple technique, which combines mechanical and hydrostatic forces to express out the nucleus. This technique is time-tested with good results and more than 95% of nuclei in MSICS are extracted in this way offering all the merits of phacoemulsification with the added benefits of having wider applicability, better safety, shorter learning curve and lower cost.

Nucleus basalis of Meynert degeneration precedes and predicts cognitive impairment in Parkinson's disease.

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Schulz, Jonathan; Pagano, Gennaro; Fernández Bonfante, Juan Alberto; Wilson, Heather; Politis, Marios

2018-05-01

Currently, no reliable predictors of cognitive impairment in Parkinson's disease exist. We hypothesized that microstructural changes at grey matter T1-weighted MRI and diffusion tensor imaging in the cholinergic system nuclei and associated limbic pathways underlie cognitive impairment in Parkinson's disease. We performed a cross-sectional comparison between patients with Parkinson's disease with and without cognitive impairment. We also performed a longitudinal 36-month follow-up study of cognitively intact Parkinson's disease patients, comparing patients who remained cognitively intact to those who developed cognitive impairment. Patients with Parkinson's disease with cognitive impairment showed lower grey matter volume and increased mean diffusivity in the nucleus basalis of Meynert, compared to patients with Parkinson's disease without cognitive impairment. These results were confirmed both with region of interest and voxel-based analyses, and after partial volume correction. Lower grey matter volume and increased mean diffusivity in the nucleus basalis of Meynert was predictive for developing cognitive impairment in cognitively intact patients with Parkinson's disease, independent of other clinical and non-clinical markers of the disease. Structural and microstructural alterations in entorhinal cortex, amygdala, hippocampus, insula, and thalamus were not predictive for developing cognitive impairment in Parkinson's disease. Our findings provide evidence that degeneration of the nucleus basalis of Meynert precedes and predicts the onset of cognitive impairment, and might be used in a clinical setting as a reliable biomarker to stratify patients at higher risk of cognitive decline.

Differential Dopamine Release Dynamics in the Nucleus Accumbens Core and Shell Reveal Complementary Signals for Error Prediction and Incentive Motivation.

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Saddoris, Michael P; Cacciapaglia, Fabio; Wightman, R Mark; Carelli, Regina M

2015-08-19

Mesolimbic dopamine (DA) is phasically released during appetitive behaviors, though there is substantive disagreement about the specific purpose of these DA signals. For example, prediction error (PE) models suggest a role of learning, while incentive salience (IS) models argue that the DA signal imbues stimuli with value and thereby stimulates motivated behavior. However, within the nucleus accumbens (NAc) patterns of DA release can strikingly differ between subregions, and as such, it is possible that these patterns differentially contribute to aspects of PE and IS. To assess this, we measured DA release in subregions of the NAc during a behavioral task that spatiotemporally separated sequential goal-directed stimuli. Electrochemical methods were used to measure subsecond NAc dopamine release in the core and shell during a well learned instrumental chain schedule in which rats were trained to press one lever (seeking; SL) to gain access to a second lever (taking; TL) linked with food delivery, and again during extinction. In the core, phasic DA release was greatest following initial SL presentation, but minimal for the subsequent TL and reward events. In contrast, phasic shell DA showed robust release at all task events. Signaling decreased between the beginning and end of sessions in the shell, but not core. During extinction, peak DA release in the core showed a graded decrease for the SL and pauses in release during omitted expected rewards, whereas shell DA release decreased predominantly during the TL. These release dynamics suggest parallel DA signals capable of supporting distinct theories of appetitive behavior. Dopamine signaling in the brain is important for a variety of cognitive functions, such as learning and motivation. Typically, it is assumed that a single dopamine signal is sufficient to support these cognitive functions, though competing theories disagree on how dopamine contributes to reward-based behaviors. Here, we have found that real

Persistent organic pollutants alter DNA methylation during human adipocyte differentiation

NARCIS (Netherlands)

Dungen, van den Myrthe W.; Murk, Albertinka J.; Gils-Kok, van Dieuwertje; Steegenga, Wilma T.

2017-01-01

Ubiquitous persistent organic pollutants (POPs) can accumulate in humans where they might influence differentiation of adipocytes. The aim of this study was to investigate whether DNA methylation is one of the underlying mechanisms by which POPs affect adipocyte differentiation, and to what

Fluorescent protein-tagged Vpr dissociates from HIV-1 core after viral fusion and rapidly enters the cell nucleus.

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Desai, Tanay M; Marin, Mariana; Sood, Chetan; Shi, Jiong; Nawaz, Fatima; Aiken, Christopher; Melikyan, Gregory B

2015-10-29

HIV-1 Vpr is recruited into virions during assembly and appears to remain associated with the viral core after the reverse transcription and uncoating steps of entry. This feature has prompted the use of fluorescently labeled Vpr to visualize viral particles and to follow trafficking of post-fusion HIV-1 cores in the cytoplasm. Here, we tracked single pseudovirus entry and fusion and observed that fluorescently tagged Vpr gradually dissociates from post-fusion viral cores over the course of several minutes and accumulates in the nucleus. Kinetics measurements showed that fluorescent Vpr released from the cores very rapidly entered the cell nucleus. More than 10,000 Vpr molecules can be delivered into the cell nucleus within 45 min of infection by HIV-1 particles pseudotyped with the avian sarcoma and leukosis virus envelope glycoprotein. The fraction of Vpr from cell-bound viruses that accumulated in the nucleus was proportional to the extent of virus-cell fusion and was fully blocked by viral fusion inhibitors. Entry of virus-derived Vpr into the nucleus occurred independently of envelope glycoproteins or target cells. Fluorescence correlation spectroscopy revealed two forms of nuclear Vpr-monomers and very large complexes, likely involving host factors. The kinetics of viral Vpr entering the nucleus after fusion was not affected by point mutations in the capsid protein that alter the stability of the viral core. The independence of Vpr shedding of capsid stability and its relatively rapid dissociation from post-fusion cores suggest that this process may precede capsid uncoating, which appears to occur on a slower time scale. Our results thus demonstrate that a bulk of fluorescently labeled Vpr incorporated into HIV-1 particles is released shortly after fusion. Future studies will address the question whether the quick and efficient nuclear delivery of Vpr derived from incoming viruses can regulate subsequent steps of HIV-1 infection.

Whole blood gene expression in adolescent chronic fatigue syndrome: an exploratory cross-sectional study suggesting altered B cell differentiation and survival.

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Nguyen, Chinh Bkrong; Alsøe, Lene; Lindvall, Jessica M; Sulheim, Dag; Fagermoen, Even; Winger, Anette; Kaarbø, Mari; Nilsen, Hilde; Wyller, Vegard Bruun

2017-05-11

Chronic fatigue syndrome (CFS) is a prevalent and disabling condition affecting adolescents. The pathophysiology is poorly understood, but immune alterations might be an important component. This study compared whole blood gene expression in adolescent CFS patients and healthy controls, and explored associations between gene expression and neuroendocrine markers, immune markers and clinical markers within the CFS group. CFS patients (12-18 years old) were recruited nation-wide to a single referral center as part of the NorCAPITAL project. A broad case definition of CFS was applied, requiring 3 months of unexplained, disabling chronic/relapsing fatigue of new onset, whereas no accompanying symptoms were necessary. Healthy controls having comparable distribution of gender and age were recruited from local schools. Whole blood samples were subjected to RNA sequencing. Immune markers were blood leukocyte counts, plasma cytokines, serum C-reactive protein and immunoglobulins. Neuroendocrine markers encompassed plasma and urine levels of catecholamines and cortisol, as well as heart rate variability indices. Clinical markers consisted of questionnaire scores for symptoms of post-exertional malaise, inflammation, fatigue, depression and trait anxiety, as well as activity recordings. A total of 29 CFS patients and 18 healthy controls were included. We identified 176 genes as differentially expressed in patients compared to controls, adjusting for age and gender factors. Gene set enrichment analyses suggested impairment of B cell differentiation and survival, as well as enhancement of innate antiviral responses and inflammation in the CFS group. A pattern of co-expression could be identified, and this pattern, as well as single gene transcripts, was significantly associated with indices of autonomic nervous activity, plasma cortisol, and blood monocyte and eosinophil counts. Also, an association with symptoms of post-exertional malaise was demonstrated. Adolescent CFS is

Does chronic nicotine alter neurotransmitter receptors involved in Parkinson's disease?

International Nuclear Information System (INIS)

Reilly, M.A.; Lapin, E.P.; Lajtha, A.; Maker, H.S.

1986-01-01

Cigarette smokers are fewer in number among Parkinson's Disease (PD) patients than among groups of persons who do not have PD. Several hypotheses have been proposed to explain this observation. One which must be tested is the possibility that some pharmacologic agent present in cigarette smoke may interact with some central nervous system component involved in PD. To this end, they have investigated the effect of chronic nicotine administration on receptors for some of the neurotransmitters that are affected in PD. Rats were injected for six weeks with saline or nicotine 0.8 mg/kg S.C., then killed and brains removed and dissected. The binding of ( 3 H)-ketanserin to serotonin receptors in frontal cortex and of ( 3 H)-domperidone to dopamine receptors in caudate was not affected. However, the binding of ( 3 H)-domperidone in nucleus accumbens was altered: the K/sub d/ increased from 0.16 +/- 0.02 nM to 0.61 +/- 0.07 nM, and the B/sub max/ increased from 507 +/- 47 fmol/mg protein to 910 +/- 43 fmol/mg (p < 0.001 for both comparisons). These values are based on three ligand concentrations. Additional studies are in progress to substantiate the data. It is concluded that chronic nicotine administration may alter dopamine receptors in nucleus accumbens

Raman spectroscopy of individual monocytes reveals that single-beam optical trapping of mononuclear cells occurs by their nucleus

International Nuclear Information System (INIS)

Fore, Samantha; Chan, James; Taylor, Douglas; Huser, Thomas

2011-01-01

We show that laser tweezers Raman spectroscopy of eukaryotic cells with a significantly larger diameter than the tight focus of a single-beam laser trap leads to optical trapping of the cell by its optically densest part, i.e. typically the cell's nucleus. Raman spectra of individual optically trapped monocytes are compared with location-specific Raman spectra of monocytes adhered to a substrate. When the cell's nucleus is stained with a fluorescent live cell stain, the Raman spectrum of the DNA-specific stain is observed only in the nucleus of individual monocytes. Optically trapped monocytes display the same behavior. We also show that the Raman spectra of individual monocytes exhibit the characteristic Raman signature of cells that have not yet fully differentiated and that individual primary monocytes can be distinguished from transformed monocytes based on their Raman spectra. This work provides further evidence that laser tweezers Raman spectroscopy of individual cells provides meaningful biochemical information in an entirely non-destructive fashion that permits discerning differences between cell types and cellular activity

Open-nucleus theory for beef cattle breeding systems: A revisitation

International Nuclear Information System (INIS)

Recami, E.; Packer, I.U.; Tenorio Vasconselos, M.

1990-07-01

A theoretical model for Open-Nucleus Systems is herein described in the case of beef cattle breeding. One of the starting points is the observation that the majority of the standard theoretical models for open-nucleus breeding systems were constructed for the case of discrete generations, i.e. for the cases in which the dam average fertility coefficient is f>2. In the case of cattle herds, when only a fraction of the breeding dams can be replaced, it is therefore worthwhile to build up anew a rather rigorous theoretical model, with overlapping generations, and check its predictions. Namely, we apply the new formulae - explicitly depending on β F , ν F , ν M , K and R - to the system in which all breeding sires are in the Nucleus (and are reared in the nucleus itself), and are mated to both Nucleus and Base dams via artificial insemination. Optimal system design has been looked for by the NAG and MINOS computation programs, operated on Vax computers. Opening the nucleus in this situation results to be very effective since the (optimum) asymptotic genetic gain per generation for ''closed nucleus'' systems (x=0) results to be, when e.g. R≡F/M≅200, more than 40% lower than the (optimum) asymptotic genetic gain, G*, for open nucleus systems. Optimal design corresponds to: (i) having a fraction p≅16% of the female population in the nucleus; (ii) replacing practically all the (nucleus) breeding sires by the best (nucleus born) males: ν M =97/98%; (iii) using for dam replacement all (b≅100%) the (base and nucleus born) females; (iv) implementing a high upward gene migration (x≅80%), while all the surplus nucleus-born females are to be used as base replacements. This corresponds to replace, at each generation, also almost all the nucleus dams (ν F ≅95/100%), and the largest possible fraction of base dams (β F ≅30%, a value changing with p). 17 refs

The momentum distribution inside nucleus

International Nuclear Information System (INIS)

Fujita, T.

1985-01-01

Discussions are made on several reactions which can determine the momentum distribution inside nucleus. The first reaction discussed is the high energy heavy ion collision. This reaction involves many nucleons which interact strongly. Therefore, one must be careful for any possible final state interactions. The expression for the single particle momentum distribution is given. And it can be said that the expression is consistent with the description of the energetic neutrons from muon capture by heavy nucleus. The best way to determine the momentum distribution would be the lepton-nucleus scattering since it does not involve the strong interaction in the initial channel. Another reaction discussed is the backward proton production, which is governed by quite complicated reaction processes. Therefore, the determination of the momentum distribution is only indirect. Noverthless, it is found that this reaction presents a very interesting and important information on the momentum distribution. (Aoki, K.)

Poorly Differentiated Thyroid Carcinoma.

Science.gov (United States)

Setia, Namrata; Barletta, Justine A

2014-12-01

Poorly differentiated thyroid carcinoma (PDTC) has been recognized for the past 30 years as an entity showing intermediate differentiation and clinical behavior between well-differentiated thyroid carcinomas (ie, papillary thyroid carcinoma and follicular thyroid carcinoma) and anaplastic thyroid carcinoma; however, there has been considerable controversy around the definition of PDTC. In this review, the evolution in the definition of PDTC, current diagnostic criteria, differential diagnoses, potentially helpful immunohistochemical studies, and molecular alterations are discussed with the aim of highlighting where the diagnosis of PDTC currently stands. Published by Elsevier Inc.

Radiative proton capture to the first excited state of sup 29 P nucleus at subbarrier energies

Energy Technology Data Exchange (ETDEWEB)

Matulewicz, T; Dabrowska, M; Decowski, P; Kicinska-Habior, M; Sikora, B [Warsaw Univ. (Poland). Inst. Fizyki Doswiadczalnej; Toke, J [Rochester Univ., NY (USA). Nuclear Structure Research Lab.; Somorjai, E [Magyar Tudomanyos Akademia, Debrecen (Hungary). Atommag Kutato Intezete

1985-08-01

Differential cross sections at 0 deg and 90 deg measured for {sup 28}Si(p,{gamma}{sub 1}){sup 29}P reaction at proton energy range 2.3-2.9 MeV have been analyzed in terms of the direct-semidirect capture model extended by the effective potential approach. Spectroscopic factor of the first excited states of {sup 29}P nucleus was found to be 0.10+-0.05. 9 refs., 1 fig. (author).

Cytoarchitectonic and quantitative Golgi study of the hedgehog supraoptic nucleus.

Science.gov (United States)

Caminero, A A; Machín, C; Sanchez-Toscano, F

1992-02-01

A cytoarchitectural study was made of the supraoptic nucleus (SON) of the hedgehog with special attention to the quantitative comparison of its main neuronal types. The main purposes were (1) to relate the characteristics of this nucleus in the hedgehog (a primitive mammalian insectivorous brain) with those in the SONs of more evolutionarily advanced species; (2) to identify quantitatively the dendritic fields of the main neuronal types in the hedgehog SON and to study their synaptic connectivity. From a descriptive standpoint, 3 neuronal types were found with respect to the number of dendritic stems arising from the neuronal soma: bipolar neurons (48%), multipolar neurons (45.5%) and monopolar neurons (6.5%). Within the multipolar type 2 subtypes could be distinguished, taking into account the number of dendritic spines: (a) with few spines (93%) and (b) very spiny (7%). These results indicate that the hedgehog SON is similar to that in other species except for the very spiny neurons, the significance of which is discussed. In order to characterise the main types more satisfactorily (bipolar and multipolars with few spines) we undertook a quantitative Golgi study of their dendritic fields. Although the patterns of the dendritic field are similar in both neuronal types, the differences in the location of their connectivity can reflect functional changes and alterations in relation to the synaptic afferences.

Role of dysphagia in evaluating Parkinson patients for subthalamic nucleus stimulation: a case report.

Science.gov (United States)

Allert, Niels; Kelm, Daniela; Spottke, Annika; Coenen, Volker A

2011-09-01

In the selection of Parkinson patients for deep brain stimulation (DBS) of the subthalamic nucleus (STN) a risk-benefit-analysis is performed regarding symptoms that commonly improve and symptoms that may deteriorate. Speech is among the symptoms that may deteriorate. In contrast, the differential effects of STN-DBS on swallowing are less clear. Here, we present a Parkinson patient with dysphagia from concomitant oculo-pharyngeal muscle dystrophy successfully treated by STN-DBS. The role of dysphagia in evaluating Parkinson patients for STN-DBS is discussed.

Differentiation as symbiosis.

Science.gov (United States)

Chigira, M; Watanabe, H

1994-07-01

Preservation of the identity of DNA is the ultimate goal of multicellular organisms. An abnormal DNA sequence in cells within an individual means its parasitic nature in cell society as shown in tumors. Somatic gene arrangement and gene mutation in development may be considered as de novo formation of parasites. It is likely that the developmental process with genetic alterations means symbiosis between altered cells and germ line cells preserving genetic information without alterations, when somatic alteration of DNA sequence is a major mechanism of differentiation. According to the selfish gene theory of Dawkins, germ line cells permit symbiosis when somatic cell society derives clear profit for the replication of original DNA copies.

Gene expression changes in the prefrontal cortex, anterior cingulate cortex and nucleus accumbens of mood disorders subjects that committed suicide.

Directory of Open Access Journals (Sweden)

Adolfo Sequeira

Full Text Available Suicidal behaviors are frequent in mood disorders patients but only a subset of them ever complete suicide. Understanding predisposing factors for suicidal behaviors in high risk populations is of major importance for the prevention and treatment of suicidal behaviors. The objective of this project was to investigate gene expression changes associated with suicide in brains of mood disorder patients by microarrays (Affymetrix HG-U133 Plus2.0 in the dorsolateral prefrontal cortex (DLPFC: 6 Non-suicides, 15 suicides, the anterior cingulate cortex (ACC: 6NS, 9S and the nucleus accumbens (NAcc: 8NS, 13S. ANCOVA was used to control for age, gender, pH and RNA degradation, with P ≤ 0.01 and fold change ± 1.25 as criteria for significance. Pathway analysis revealed serotonergic signaling alterations in the DLPFC and glucocorticoid signaling alterations in the ACC and NAcc. The gene with the lowest p-value in the DLPFC was the 5-HT2A gene, previously associated both with suicide and mood disorders. In the ACC 6 metallothionein genes were down-regulated in suicide (MT1E, MT1F, MT1G, MT1H, MT1X, MT2A and three were down-regulated in the NAcc (MT1F, MT1G, MT1H. Differential expression of selected genes was confirmed by qPCR, we confirmed the 5-HT2A alterations and the global down-regulation of members of the metallothionein subfamilies MT 1 and 2 in suicide completers. MTs 1 and 2 are neuro-protective following stress and glucocorticoid stimulations, suggesting that in suicide victims neuroprotective response to stress and cortisol may be diminished. Our results thus suggest that suicide-specific expression changes in mood disorders involve both glucocorticoids regulated metallothioneins and serotonergic signaling in different regions of the brain.

Gene expression changes in the prefrontal cortex, anterior cingulate cortex and nucleus accumbens of mood disorders subjects that committed suicide.

Science.gov (United States)

Sequeira, Adolfo; Morgan, Ling; Walsh, David M; Cartagena, Preston M; Choudary, Prabhakara; Li, Jun; Schatzberg, Alan F; Watson, Stanley J; Akil, Huda; Myers, Richard M; Jones, Edward G; Bunney, William E; Vawter, Marquis P

2012-01-01

Suicidal behaviors are frequent in mood disorders patients but only a subset of them ever complete suicide. Understanding predisposing factors for suicidal behaviors in high risk populations is of major importance for the prevention and treatment of suicidal behaviors. The objective of this project was to investigate gene expression changes associated with suicide in brains of mood disorder patients by microarrays (Affymetrix HG-U133 Plus2.0) in the dorsolateral prefrontal cortex (DLPFC: 6 Non-suicides, 15 suicides), the anterior cingulate cortex (ACC: 6NS, 9S) and the nucleus accumbens (NAcc: 8NS, 13S). ANCOVA was used to control for age, gender, pH and RNA degradation, with P ≤ 0.01 and fold change ± 1.25 as criteria for significance. Pathway analysis revealed serotonergic signaling alterations in the DLPFC and glucocorticoid signaling alterations in the ACC and NAcc. The gene with the lowest p-value in the DLPFC was the 5-HT2A gene, previously associated both with suicide and mood disorders. In the ACC 6 metallothionein genes were down-regulated in suicide (MT1E, MT1F, MT1G, MT1H, MT1X, MT2A) and three were down-regulated in the NAcc (MT1F, MT1G, MT1H). Differential expression of selected genes was confirmed by qPCR, we confirmed the 5-HT2A alterations and the global down-regulation of members of the metallothionein subfamilies MT 1 and 2 in suicide completers. MTs 1 and 2 are neuro-protective following stress and glucocorticoid stimulations, suggesting that in suicide victims neuroprotective response to stress and cortisol may be diminished. Our results thus suggest that suicide-specific expression changes in mood disorders involve both glucocorticoids regulated metallothioneins and serotonergic signaling in different regions of the brain.

Structural dynamics of the cell nucleus

Science.gov (United States)

Wiegert, Simon; Bading, Hilmar

2011-01-01

Neuronal morphology plays an essential role in signal processing in the brain. Individual neurons can undergo use-dependent changes in their shape and connectivity, which affects how intracellular processes are regulated and how signals are transferred from one cell to another in a neuronal network. Calcium is one of the most important intracellular second messengers regulating cellular morphologies and functions. In neurons, intracellular calcium levels are controlled by ion channels in the plasma membrane such as NMDA receptors (NMDARs), voltage-gated calcium channels (VGCCs) and certain α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) as well as by calcium exchange pathways between the cytosol and internal calcium stores including the endoplasmic reticulum and mitochondria. Synaptic activity and the subsequent opening of ligand and/or voltage-gated calcium channels can initiate cytosolic calcium transients which propagate towards the cell soma and enter the nucleus via its nuclear pore complexes (NPCs) embedded in the nuclear envelope. We recently described the discovery that in hippocampal neurons the morphology of the nucleus affects the calcium dynamics within the nucleus. Here we propose that nuclear infoldings determine whether a nucleus functions as an integrator or detector of oscillating calcium signals. We outline possible ties between nuclear mophology and transcriptional activity and discuss the importance of extending the approach to whole cell calcium signal modeling in order to understand synapse-to-nucleus communication in healthy and dysfunctional neurons. PMID:21738832

Cloud Particles Differential Evolution Algorithm: A Novel Optimization Method for Global Numerical Optimization

Directory of Open Access Journals (Sweden)

Wei Li

2015-01-01

Full Text Available We propose a new optimization algorithm inspired by the formation and change of the cloud in nature, referred to as Cloud Particles Differential Evolution (CPDE algorithm. The cloud is assumed to have three states in the proposed algorithm. Gaseous state represents the global exploration. Liquid state represents the intermediate process from the global exploration to the local exploitation. Solid state represents the local exploitation. The best solution found so far acts as a nucleus. In gaseous state, the nucleus leads the population to explore by condensation operation. In liquid state, cloud particles carry out macrolocal exploitation by liquefaction operation. A new mutation strategy called cloud differential mutation is introduced in order to solve a problem that the misleading effect of a nucleus may cause the premature convergence. In solid state, cloud particles carry out microlocal exploitation by solidification operation. The effectiveness of the algorithm is validated upon different benchmark problems. The results have been compared with eight well-known optimization algorithms. The statistical analysis on performance evaluation of the different algorithms on 10 benchmark functions and CEC2013 problems indicates that CPDE attains good performance.

Strangeness production in nucleus-nucleus collisions: An experimental review

International Nuclear Information System (INIS)

Odyniec, G.

1990-12-01

In experiments with oxygen (60 and 200 GeV/N) and sulphur (200 GeV/N) ions at CERNSPS, large energy densities of the order of 2--3 GeV/fm 3 have been observed, which according to QCD calculations, satisfy necessary conditions for the formation of a quark gluon plasma (QGP) phase. Under such conditions, colour would no longer be confined to hadronic dimensions, and quarks and gluons will propagate freely throughout an extended volume. Somehow lower energy densities, of the order of 0.7--1 GeV/fm 3 , were observed in AGS experiments with 15 GeV/N silicon beams and heavy targets. These energy densities might be adequate for investigations of the pre-equilibrium stage, during which the momentum space distribution has been degradated from its initial value but is not yet thermal. First experimental results, available now, show promise of seeing signs of a new phase of matter. In this review the current status of the selective experimental results on strange-particle production, which are relevant to equilibration and QGP formation in nucleus-nucleus collisions, is presented

Applying the elastic model for various nucleus-nucleus fusion

International Nuclear Information System (INIS)

HASSAN, G.S.; RAGAB, H.S.; SEDDEEK, M.K.

2000-01-01

The Elastic Model of two free parameters m,d given by Scalia has been used for wider energy regions to fit the available experimental data for potential barriers and cross sections. In order to generalize Scalia's formula in both sub- and above-barrier regions, we calculated m, d for pairs rather than those given by Scalia and compared the calculated cross sections with the experimental data. This makes a generalization of the Elastic Model in describing fusion process. On the other hand, Scalia's range of interacting systems was 24 ≤ A ≤194 where A is the compound nucleus mass number. Our extension of that model includes an example of the pairs of A larger than his final limit aiming to make it as a general formula for any type of reactants: light, intermediate or heavy systems. A significant point is the comparison of Elastic Model calculations with the well known methods studying complete fusion and compound nucleus formation, namely with the resultants of using Proximity potential with either Sharp or Smooth cut-off approximations

Nucleus-size pinning for determination of nucleation free-energy barriers and nucleus geometry

Science.gov (United States)

Sharma, Abhishek K.; Escobedo, Fernando A.

2018-05-01

Classical Nucleation Theory (CNT) has recently been used in conjunction with a seeding approach to simulate nucleation phenomena at small-to-moderate supersaturation conditions when large free-energy barriers ensue. In this study, the conventional seeding approach [J. R. Espinosa et al., J. Chem. Phys. 144, 034501 (2016)] is improved by a novel, more robust method to estimate nucleation barriers. Inspired by the interfacial pinning approach [U. R. Pedersen, J. Chem. Phys. 139, 104102 (2013)] used before to determine conditions where two phases coexist, the seed of the incipient phase is pinned to a preselected size to iteratively drive the system toward the conditions where the seed becomes a critical nucleus. The proposed technique is first validated by estimating the critical nucleation conditions for the disorder-to-order transition in hard spheres and then applied to simulate and characterize the highly non-trivial (prolate) morphology of the critical crystal nucleus in hard gyrobifastigia. A generalization of CNT is used to account for nucleus asphericity and predict nucleation free-energy barriers for gyrobifastigia. These predictions of nuclei shape and barriers are validated by independent umbrella sampling calculations.

Roentgenological findings in muscular alterations of extremities

International Nuclear Information System (INIS)

Palvoelgyi, R.

1978-01-01

A survey of roentgenological findings in muscular alterations of extremities based on the author's experiences and on the literature is presented. Following a description of the normal roentgen anatomy, the alterations in different diseases of interstitial lipomatosis are demonstrated. By roentgenological examinations differt muscular lesions of the extremities can be differentiated and the clinical follow-up verified. (orig.) [de

Do migrating cells need a nucleus?

Science.gov (United States)

Hawkins, Rhoda J

2018-03-05

How the nucleus affects cell polarity and migration is unclear. In this issue, Graham et al. (2018. J. Cell Biol. https://doi.org/10.1083/jcb.201706097) show that enucleated cells polarize and migrate in two but not three dimensions and propose that the nucleus is a necessary component of the molecular clutch regulating normal mechanical responses. © 2018 Hawkins.

Study of high energy densities over extended nuclear volumes via nucleus-nucleus collisions at the SPS

CERN Multimedia

2002-01-01

This experiment examines in detail the characteristics of ultra-relativistic nucleus-nucleus interactions using $^{16}$O beams of 200 GeV/A from the SPS. The experiment combines 4$\\pi$ calorimeter coverage with measurements of inclusive particle spectra, two-particle correlations, low and high-mass lepton pairs and photons. A multiwire active target allows maximum interaction rates with a minimum of secondary interactions. Additional data are taken with an emulsion target.

International Halley Watch: Discipline specialists for near-nucleus studies

Science.gov (United States)

Larson, S.; Sekanina, Z.; Rahe, J.

1986-01-01

The purpose of the Near-Nucleus Studies Net is to study the processes taking place in the near-nucleus environment as they relate to the nature of nucleus. This is accomplisghed by measuring the spatial and temporal distribution of dust, gases and ions in the coma on high resolution images taken from many observatories around the world. By modeling the motions of discrete dust features in Comet Halley, it is often possible to determine the locations of the emission sources on the surface and learn about the nucleus structure. In addition to the general goals shared by all IHW nets, the scientific goals of the net has been to determine (1)the gross surface structure of the nucleus, (2)the nucleus spin vector, (3)the distribution and evolution of jet sources and (4)the interrelationships between the gas, dust and ion components of the coma. An additional Comet Giacobini-Zinner watch was carried out by the NNSN in support of the NASA International Cometary Explorer flyby.

Glycogen synthase kinase 3 beta alters anxiety-, depression-, and addiction-related behaviors and neuronal activity in the nucleus accumbens shell

Science.gov (United States)

Crofton, Elizabeth J.; Nenov, Miroslav N.; Zhang, Yafang; Scala, Federico; Page, Sean A.; McCue, David L.; Li, Dingge; Hommel, Jonathan D.; Laezza, Fernanda; Green, Thomas A.

2017-01-01

Psychiatric disorders such as anxiety, depression and addiction are often comorbid brain pathologies thought to share common mechanistic biology. As part of the cortico-limbic circuit, the nucleus accumbens shell (NAcSh) plays a fundamental role in integrating information in the circuit, such that modulation of NAcSh circuitry alters anxiety, depression, and addiction-related behaviors. Intracellular kinase cascades in the NAcSh have proven important mediators of behavior. To investigate glycogen-synthase kinase 3 (GSK3) beta signaling in the NAcSh in vivo we knocked down GSK3beta expression with a novel adeno-associated viral vector (AAV2) and assessed changes in anxiety- and depression-like behavior and cocaine self-administration in GSK3beta knockdown rats. GSK3beta knockdown reduced anxiety-like behavior while increasing depression-like behavior and cocaine self-administration. Correlative electrophysiological recordings in acute brain slices were used to assess the effect of AAV-shGSK3beta on spontaneous firing and intrinsic excitability of tonically active interneurons (TANs), cells required for input and output signal integration in the NAcSh and for processing reward-related behaviors. Loose-patch recordings showed that TANs transduced by AAV-shGSK3beta exhibited reduction in tonic firing and increased spike half width. When assessed by whole-cell patch clamp recordings these changes were mirrored by reduction in action potential firing and accompanied by decreased hyperpolarization-induced depolarizing sag potentials, increased action potential current threshold, and decreased maximum rise time. These results suggest that silencing of GSK3beta in the NAcSh increases depression- and addiction-related behavior, possibly by decreasing intrinsic excitability of TANs. However, this study does not rule out contributions from other neuronal sub-types. PMID:28126496

The ovine sexually dimorphic nucleus, aromatase, and sexual partner preferences in sheep.

Science.gov (United States)

Roselli, C E; Stormshak, F

2010-02-28

We are using the domestic ram as an experimental model to examine the role of aromatase in the development of sexual partner preferences. This interest has arisen because of the observation that as many as 8% of domestic rams are sexually attracted to other rams (male-oriented) in contrast to the majority of rams that are attracted to estrous ewes (female-oriented). Our findings demonstrate that aromatase expression is enriched in a cluster of neurons in the medial preoptic nucleus called the ovine sexually dimorphic nucleus (oSDN). The size of the oSDN is associated with a ram's sexual partner preference, such that the nucleus is 2-3 times larger in rams that are attracted to females (female-oriented) than in rams that are attracted to other rams (male-oriented). Moreover, the volume of the oSDN in male-oriented rams is similar to the volume in ewes. These volume differences are not influenced by adult concentrations of serum testosterone. Instead, we found that the oSDN is already present in late gestation lamb fetuses (approximately day 135 of gestation) when it is approximately 2-fold greater in males than in females. Exposure of genetic female fetuses to exogenous testosterone during the critical period for sexual differentiation masculinizes oSDN volume and aromatase expression when examined subsequently on day 135. The demonstration that the oSDN is organized prenatally by testosterone exposure suggests that the brain of the male-oriented ram may be under-androgenized during development. Copyright 2009 Elsevier Ltd. All rights reserved.

Study of Strange and Multistrange Particles in Ultrarelativistic Nucleus-Nucleus Collisions

CERN Multimedia

Vande vyvre, P; Feofilov, G; Snoeys, W; Hetland, K F; Campbell, M; Klempt, W

2002-01-01

% NA57\\\\ \\\\ The goal of the experiment is to study the production of strange and multi-strange particles in nucleus-nucleus collisions. This study was initiated at the OMEGA spectrometer, where three ion experiments have been performed: WA85 (S-W and p-W collisions at 200 A GeV/c), WA94 (S-S and p-S collisions at 200 A GeV/c) and WA97 (Pb-Pb, p-Pb and p-Be collisions at 160 A GeV/c).\\\\ \\\\ The experiment aims at extending the scope of WA97 by:\\\\ \\\\ - investigating the beam energy dependence of the enhancements of multi-strange particle production reported by the previous experiments, and by\\\\ \\\\\\\\ \\\\- measuring the yields of strange and multi-strange particles over an extended centrality range compared with the previous experiments.\\\\ \\\\ The apparatus consists mainly of silicon pixel detector planes.

AgRP and NPY Expression in the Human Hypothalamic Infundibular Nucleus Correlate with Body Mass Index, Whereas Changes in alpha MSH Are Related to Type 2 Diabetes

NARCIS (Netherlands)

Alkemade, Anneke; Yi, Chun-Xia; Pei, Lei; Harakalova, Magdalena; Swaab, Dick F.; la Fleur, Susanne E.; Fliers, Eric; Kalsbeek, Andries

2012-01-01

Context: Rodent data show that altered hypothalamic signaling contributes to the development of obesity and insulin resistance. Objective: To determine differences in hypothalamic expression levels of neuropeptide Y (NPY), agouti-related peptide (AgRP), and alpha MSH in the infundibular nucleus, the

The picture of the nuclei disintegration mechanism - from nucleus-nucleus collision experimental data at high energies

International Nuclear Information System (INIS)

Strugalska-Gola, E.; Strugalski, Z.

1997-01-01

Experimental data on nuclear collisions at high energies, mainly obtained from photographic emulsions, are considered from the point of view of the picture of the nuclear collision processes mechanisms prompted experimentally. In fact, the disintegration products of each nucleus involved in a nuclear collision, in its own rest-frame, are similar to that produced by the impact of a number of nucleons of velocity equal to that of the moving primary nucleus

The nucleus in Finland - The second report

International Nuclear Information System (INIS)

Aurela, Jorma; Korteniemi, Virpi; Halme-Tapanainen, Kristina

1993-01-01

The Finnish Nuclear Society (FNS) started the distribution of the Nucleus bulletin at the beginning of 1988. The volume of distribution has been extended since, including today nearly 1,000 persons. Both the English and the Finnish version of the bulletin is sent to various opinion leaders of society, i.e. the members of the parliament, ministries, the media, representatives of industry and other decision-makers of the energy field. After the five-year history of the Nucleus in Finland, it is time to look back and sum up the present status of the Nucleus. This report gives a short summary concerning the present distribution and its efficiency, the experiences gained and the influence of the bulletin in Finland. The first questionnaire was sent in November 1988, and the survey was repeated among the Finnish readers of the Nucleus in autumn 1992. The results of the latter survey are given in this report

Desipramine and citalopram attenuate pretest swim-induced increases in prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis and the lateral division of the central nucleus of the amygdala in the forced swimming test.

Science.gov (United States)

Chung, Sung; Kim, Hee Jeong; Kim, Hyun Ju; Choi, Sun Hye; Cho, Jin Hee; Cho, Yun Ha; Kim, Dong-Hoon; Shin, Kyung Ho

2014-10-01

Dynorphin in the nucleus accumbens shell plays an important role in antidepressant-like effect in the forced swimming test (FST), but it is unclear whether desipramine and citalopram treatments alter prodynorphin levels in other brain areas. To explore this possibility, we injected mice with desipramine and citalopram 0.5, 19, and 23 h after a 15-min pretest swim and observed changes in prodynorphin expression before the test swim, which was conducted 24 h after the pretest swim. The pretest swim increased prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis (dBNST) and lateral division of the central nucleus of the amygdala (CeL). This increase in prodynorphin immunoreactivity in the dBNST and CeL was blocked by desipramine and citalopram treatments. Similar changes in prodynorphin mRNA levels were observed in the dBNST and CeL, but these changes did not reach significance. To understand the underlying mechanism, we assessed changes in phosphorylated CREB at Ser(133) (pCREB) immunoreactivity in the dBNST and central nucleus of the amygdala (CeA). Treatment with citalopram but not desipramine after the pretest swim significantly increased pCREB immunoreactivity only in the dBNST. These results suggest that regulation of prodynorphin in the dBNST and CeL before the test swim may be involved in the antidepressant-like effect of desipramine and citalopram in the FST and suggest that changes in pCREB immunoreactivity in these areas may not play an important role in the regulation of prodynorphin in the dBNST and CeA. Copyright © 2014 Elsevier Ltd. All rights reserved.

Experimental and phenomenological investigations of QCD matter in high-energy nucleus-nucleus collisions

Energy Technology Data Exchange (ETDEWEB)

Andronic, Anton

2014-07-15

This thesis is heterogeneous, comprising experimental papers at low energies (SIS-18 at GSI) and at the LHC, papers on phenomenology of high-energy nucleus-nucleus collisions, and papers on detectors. The overview covers the experimental papers and those on phenomenology. I have chosen to write it in a general manner, intended to be accessible to non-experts. It emphasizes recent measurements and their understanding at the LHC. The detector papers, which address many principle aspects of gaseous detectors, are summarized and placed in context in the review I co-wrote and which closes the stack. The detector papers included here are the outcome of an R and D program for the Transition Radiation Detector of ALICE.

Experimental and phenomenological investigations of QCD matter in high-energy nucleus-nucleus collisions

International Nuclear Information System (INIS)

Andronic, Anton

2014-07-01

This thesis is heterogeneous, comprising experimental papers at low energies (SIS-18 at GSI) and at the LHC, papers on phenomenology of high-energy nucleus-nucleus collisions, and papers on detectors. The overview covers the experimental papers and those on phenomenology. I have chosen to write it in a general manner, intended to be accessible to non-experts. It emphasizes recent measurements and their understanding at the LHC. The detector papers, which address many principle aspects of gaseous detectors, are summarized and placed in context in the review I co-wrote and which closes the stack. The detector papers included here are the outcome of an R and D program for the Transition Radiation Detector of ALICE.

Brain grey matter volume alterations in late-life depression.

Science.gov (United States)

Du, Mingying; Liu, Jia; Chen, Ziqi; Huang, Xiaoqi; Li, Jing; Kuang, Weihong; Yang, Yanchun; Zhang, Wei; Zhou, Dong; Bi, Feng; Kendrick, Keith M; Gong, Qiyong

2014-11-01

Voxel-based morphometry (VBM) studies have demonstrated that grey matter abnormalities are involved in the pathophysiology of late-life depression (LLD), but the findings are inconsistent and have not been quantitatively reviewed. The aim of the present study was to conduct a meta-analysis that integrated the reported VBM studies, to determine consistent grey matter alterations in individuals with LLD. A systematic search was conducted to identify VBM studies that compared patients with LLD and healthy controls. We performed a meta-analysis using the effect size signed differential mapping method to quantitatively estimate regional grey matter abnormalities in patients with LLD. We included 9 studies with 11 data sets comprising 292 patients with LLD and 278 healthy controls in our meta-analysis. The pooled and subgroup meta-analyses showed robust grey matter reductions in the right lentiform nucleus extending into the parahippocampus, the hippocampus and the amygdala, the bilateral medial frontal gyrus and the right subcallosal gyrus as well as a grey matter increase in the right lingual gyrus. Meta-regression analyses showed that mean age and the percentage of female patients with LLD were not significantly related to grey matter changes. The analysis techniques, patient characteristics and clinical variables of the studies included were heterogeneous, and most participants were medicated. The present meta-analysis is, to our knowledge, the first to overcome previous inconsistencies in the VBM studies of LLD and provide robust evidence for grey matter alterations within fronto-striatal-limbic networks, thereby implicating them in the pathophysiology of LLD. The mean age and the percentage of female patients with LLD did not appear to have a measurable impact on grey matter changes, although we cannot rule out the contributory effects of medication.

Dissipation and fluctuation of the relative momentum in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Feldmeier, H.; Spangenberger, H.

1984-07-01

The dissipation of the relative momentum in nucleus-nucleus collisions is treated in terms of a Langevin equation with a fluctuating force. Equations of motion for first and second moments of the macroscopic variables are derived directly from the Langevin equation. The properties of the fluctuating force which results from random particle exchange are investigated in detail. Drift and diffusion coefficients are calculated microscopically and analytical expressions are given which can be used in any trajectory calculation. An important feature of the model is that the Einstein relation between dissipation and fluctuation turns out to be only a limiting case of a more general expression which included nonthermal fluctuations. By treating the two nuclei as intrinsically equilibrated but not in thermal equilibrium with respect to each other several important aspects of the dissipative behaviour, seen in heavy ion collisions with final energies above the Coloumb barrier, can be understood. (orig.)

Dynamical and statistical aspects in nucleus-nucleus collisions around the Fermi energy

Energy Technology Data Exchange (ETDEWEB)

Tamain, B.; Bocage, F.; Bougault, R.; Brou, R. [Caen Univ., 14 (France). Lab. de Physique Corpusculaire; Assenard, M. [Centre National de la Recherche Scientifique, 44 - Nantes (France). Lab. de Physique Subatomique et des Technologies Associees; Auger, G.; Benlliure, J. [Grand Accelerateur National d`Ions Lourds (GANIL), 14 - Caen (France); Bacri, C.O.; Borderie, B. [Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire; Bisquer, E. [Lyon-1 Univ., 69 - Villeurbanne (France). Inst. de Physique Nucleaire] [and others

1997-12-31

Nucleus-nucleus collisions at low incident energy are mainly governed by statistical dissipative processes, fusion and deep inelastic reactions being the most important ones. Conversely, in the relativistic energy regime, dynamical effects play a dominant role and one should apply a participant-spectator picture in order to understand the data. In between, the intermediate energy region is a transition one in which it is necessary to disentangle dynamics from statistical effects. Moreover, the Fermi energy region corresponds to available energies comparable with nuclear binding energies and one may except to observe phase transition effects. Experiments performed recently with 4{pi} devices have given quite new data and a much better insight into involved mechanisms and hot nuclear matter properties. INDRA data related to reaction mechanisms and multifragmentation are presented. (author) 53 refs.

Dynamical and statistical aspects in nucleus-nucleus collisions around the Fermi energy

International Nuclear Information System (INIS)

Tamain, B.; Bocage, F.; Bougault, R.; Brou, R.; Bacri, C.O.; Borderie, B.; Bisquer, E.

1997-01-01

Nucleus-nucleus collisions at low incident energy are mainly governed by statistical dissipative processes, fusion and deep inelastic reactions being the most important ones. Conversely, in the relativistic energy regime, dynamical effects play a dominant role and one should apply a participant-spectator picture in order to understand the data. In between, the intermediate energy region is a transition one in which it is necessary to disentangle dynamics from statistical effects. Moreover, the Fermi energy region corresponds to available energies comparable with nuclear binding energies and one may except to observe phase transition effects. Experiments performed recently with 4π devices have given quite new data and a much better insight into involved mechanisms and hot nuclear matter properties. INDRA data related to reaction mechanisms and multifragmentation are presented. (author)

Recent results on (anti)nucleus and (anti)hyperon production in nucleus-nucleus collisions at CERN SPS energies

CERN Document Server

Melkumov, G L; Anticic, T; Baatar, B; Barna, D; Bartke, J; Betev, L; Bialkowska, H; Blume, C; Boimska, B; Botje, M; Bracinik, J; Bramm, R; Buncic, P; Cerny, V; Christakoglou, P; Chung, P; Chvala, O; Cramer, J G; Csató, P; Dinkelaker, P; Eckardt, V; Flierl, D; Fodor, Z; Foka, P; Friese, V; Gál, J; Gazdzicki, M; Genchev, V; Georgopoulos, G; Grebieszkow, K; Hegyi, S; Höhne, C; Kadija, K; Karev, A; Kikola, D; Gladysz-Dziadus, E; Kliemant, M; Kniege, S; Kolesnikov, V I; Kornas, E; Korus, R; Kowalski, M; Kraus, I; Kreps, M; Laszlo, A; Lacey, R; Van Leeuwen, M; Lvai, P; Litov, L; Lungwitz, B; Makariev, M; Malakhov, A I; Mateev, M; Melkumov, G L; Mischke, A; Mitrovski, M; Molnár, J; Mrówczynski, S; Nicolic, V; Pálla, G; Panagiotou, A D; Panayotov, D; Petridis, A; Peryt, W; Pikna, M; Pluta, J; Prindle, D; Pühlhofer, F; Renfordt, R; Roland, C; Roland5, G; Rybczynski, M; Rybicki, A; Sandoval, A; Schmitz, N; Schuster, T; Siklér, F; Sitár, B; Skrzypczak, E; Slodkowski, M; Stefanek, G; Stock, R; Seyboth, P; Strabel, C; Ströbele, H; Susa, T; Szentpetery, I; Sziklai, J; Szuba, M; Szymanski, P; Trubnikov, V; Varga, D; Vassiliou, M; Veres, G I; Vesztergombi, G; Vranic, D; Wlodarczyk, Z; Wojtaszek11, A; Yoo, I K; Zimnyi, J; Wetzler, A

2007-01-01

The NA49 experiment has collected comprehensive data on particle production in nucleus-nucleus collisions over the whole SPS beam energies range, the critical energy domain where the expected phase transition to a deconfined phase is expected to occur. The latest results from Pb+Pb collisions between 20$A$ GeV and 158$A$ GeV on baryon stopping and light nuclei production as well as those for strange hyperons are presented. The measured data on $p$, $\\bar{p}$, $\\Lambda$, $\\bar{\\Lambda}$, $\\Xi^-$ and $\\bar{\\Xi}^+$ production were used to evaluate the rapidity distributions of net-baryons at SPS energies and to compare with the results from the AGS and the RHIC for central Pb+Pb (Au+Au) collisions. The dependence of the yield ratios and the inverse slope parameter of the $m_t$ spectra on the collision energy and centrality, and the mass number of the produced nuclei $^3He$, $t$, $d$ and $\\bar{d}$ are discussed within coalescence and statistical approaches. Analysis of the total multiplicity exhibits remarkable a...

Extracellular matrix production by nucleus pulposus and bone marrow stem cells in response to altered oxygen and glucose microenvironments.

Science.gov (United States)

Naqvi, Syeda M; Buckley, Conor T

2015-12-01

Bone marrow (BM) stem cells may be an ideal source of cells for intervertebral disc (IVD) regeneration. However, the harsh biochemical microenvironment of the IVD may significantly influence the biological and metabolic vitality of injected stem cells and impair their repair potential. This study investigated the viability and production of key matrix proteins by nucleus pulposus (NP) and BM stem cells cultured in the typical biochemical microenvironment of the IVD consisting of altered oxygen and glucose concentrations. Culture-expanded NP cells and BM stem cells were encapsulated in 1.5% alginate and ionically crosslinked to form cylindrical hydrogel constructs. Hydrogel constructs were maintained under different glucose concentrations (1, 5 and 25 mM) and external oxygen concentrations (5 and 20%). Cell viability was measured using the Live/Dead® assay and the production of sulphated glycosaminoglycans (sGAG), and collagen was quantified biochemically and histologically. For BM stem cells, IVD-like micro-environmental conditions (5 mM glucose and 5% oxygen) increased the accumulation of sGAG and collagen. In contrast, low glucose conditions (1 mM glucose) combined with 5% external oxygen concentration promoted cell death, inhibiting proliferation and the accumulation of sGAG and collagen. NP-encapsulated alginate constructs were relatively insensitive to oxygen concentration or glucose condition in that they accumulated similar amounts of sGAG under all conditions. Under IVD-like microenvironmental conditions, NP cells were found to have a lower glucose consumption rate compared with BM cells and may in fact be more suitable to adapt and sustain the harsh microenvironmental conditions. Considering the highly specialised microenvironment of the central NP, these results indicate that IVD-like concentrations of low glucose and low oxygen are critical and influential for the survival and biological behaviour of stem cells. Such findings may promote and accelerate

A new version of DWPI (inelastic pion-nucleus scattering) to incorporate microscopic form factors and differing proton and neutron radii

International Nuclear Information System (INIS)

Funsten, H.O.

1979-01-01

This is a modification of the Eisenstein-Miller program for calculation of collective inelastic pion-nucleus differential cross sections using free π-N scattering amplitudes. This revision permits the additional use of microscopic (shell model) proton and neutron form factors. It also incorporates separate proton and neutron radii for the nuclear density rho(r) generating the distorted wave optical potential. (Auth.)

Ethanol and phencyclidine interact with respect to nucleus accumbens dopamine release: differential effects of administration order and pretreatment protocol

Directory of Open Access Journals (Sweden)

Chris Pickering

2010-06-01

Full Text Available Executive dysfunction is a common symptom among alcohol-dependent individuals. Phencyclidine (PCP injection induces dysfunction in the prefrontal cortex of animals but little is known about how PCP affects the response to ethanol. Using the in vivo microdialysis technique in male Wistar rats, we investigated how systemic injection of 5 mg/kg PCP would affect the dopamine release induced by local infusion of 300 mM ethanol into the nucleus accumbens. PCP given 60 min before ethanol entirely blocked ethanol-induced dopamine release. However, when ethanol was administered 60 min before PCP, both drugs induced dopamine release and PCP’s effect was potentiated by ethanol (180% increase vs 150%. To test the role of prefrontal cortex dysfunction in ethanol reinforcement, animals were pre-treated for 5 days with 2.58 mg/kg PCP according to previously used ‘PFC hypofunction protocols’. This, however, did not change the relative response to PCP or ethanol compared to saline-treated controls. qPCR illustrated that this PCP dose did not significantly change expression of glucose transporters Glut1 (SLC2A1 or Glut3 (SLC2A3, monocarboxylate transporter MCT2 (SLC16A7, glutamate transporters GLT-1 (SLC1A2 or GLAST (SLC1A3, the immediate early gene Arc (Arg3.1 or GABAergic neuron markers GAT-1 (SLC6A1 and parvalbumin. Therefore, we concluded that PCP at a dose of 2.58 mg/kg for 5 days did not induce hypofunction in Wistar rats. However, PCP and ethanol do have overlapping mechanisms of action and these drugs differentially affect mesolimbic dopaminergic transmission depending on the order of administration.

New quasibound states of the compound nucleus in α -particle capture by the nucleus

Science.gov (United States)

Maydanyuk, Sergei P.; Zhang, Peng-Ming; Zou, Li-Ping

2017-07-01

We generalize the theory of nuclear decay and capture of Gamow that is based on tunneling through the barrier and internal oscillations inside the nucleus. In our formalism an additional factor is obtained, which describes distribution of the wave function of the the α particle inside the nuclear region. We discover new most stable states (called quasibound states) of the compound nucleus (CN) formed during the capture of α particle by the nucleus. With a simple example, we explain why these states cannot appear in traditional calculations of the α capture cross sections based on monotonic penetrabilities of a barrier, but they appear in a complete description of the evolution of the CN. Our result is obtained by a complete description of the CN evolution, which has the advantages of (1) a clear picture of the formation of the CN and its disintegration, (2) a detailed quantum description of the CN, (3) tests of the calculated amplitudes based on quantum mechanics (not realized in other approaches), and (4) high accuracy of calculations (not achieved in other approaches). These peculiarities are shown with the capture reaction of α +44Ca . We predict quasibound energy levels and determine fusion probabilities for this reaction. The difference between our approach and theory of quasistationary states with complex energies applied for the α capture is also discussed. We show (1) that theory does not provide calculations for the cross section of α capture (according to modern models of the α capture), in contrast with our formalism, and (2) these two approaches describe different states of the α capture (for the same α -nucleus potential).

Alteration of plant meristem function by manipulation of the Retinoblastoma-like plant RRB gene

Science.gov (United States)

Durfee, Tim [Madison, WI; Feiler, Heidi [Albany, CA; Gruissem, Wilhelm [Forch, CH; Jenkins, Susan [Martinez, CA; Roe, Judith [Manhattan, KS; Zambryski, Patricia [Berkeley, CA

2007-01-16

This invention provides methods and compositions for altering the growth, organization, and differentiation of plant tissues. The invention is based on the discovery that, in plants, genetically altering the levels of Retinoblastoma-related gene (RRB) activity produces dramatic effects on the growth, proliferation, organization, and differentiation of plant meristem.

The atomic nucleus as a target

International Nuclear Information System (INIS)

Strugalski, Z.; Pawlak, T.

1981-01-01

The purpose of this article is to characterize the atomic nucleus used as a target in hadron-nucleus collision experiments. The atomic nucleus can be treated as a lens-shaped ''slab'' of nuclear matter. Such ''slab'' should be characterized by the nuclear matter layer thickness at any impact parameter, by its average thickness, and by its maximal thickness. Parameters characterizing atomic nuclei as targets are given for the elements: 6 12 C, 7 14 N, 8 16 O, 9 19 F, 10 20 Ne, 13 27 Al, 14 28 Si, 16 32 S, 18 40 Ar, 24 52 Cr, 26 54 Fe, 27 59 Co, 29 64 Cu, 30 65 Zn, 32 73 Ge, 35 80 Br, 47 100 Ag, 53 127 I, 54 131 Xe, 73 181 Ta, 74 184 W, 79 197 Au, 82 207 Pb, 92 -- 238 U [ru

Sensitivity analysis of discharge patterns of subthalamic nucleus in the model of basal ganglia in Parkinson disease.

Science.gov (United States)

Singh, Jyotsna; Singh, Phool; Malik, Vikas

2017-01-01

Parkinson disease alters the information patterns in movement related pathways in brain. Experimental results performed on rats show that the activity patterns changes from single spike activity to mixed burst mode in Parkinson disease. However the cause of this change in activity pattern is not yet completely understood. Subthalamic nucleus is one of the main nuclei involved in the origin of motor dysfunction in Parkinson disease. In this paper, a single compartment conductance based model is considered which focuses on subthalamic nucleus and synaptic input from globus pallidus (external). This model shows highly nonlinear behavior with respect to various intrinsic parameters. Behavior of model has been presented with the help of activity patterns generated in healthy and Parkinson condition. These patterns have been compared by calculating their correlation coefficient for different values of intrinsic parameters. Results display that the activity patterns are very sensitive to various intrinsic parameters and calcium shows some promising results which provide insights into the motor dysfunction.

A plausible picture of high-energy proton-nucleus collisions

International Nuclear Information System (INIS)

Kim, C.O.

1976-01-01

Results experimentally obtained from jets of E(p)=10-10 3 GeV in nuclear emulsion show that the target nucleus in proton-nucleus collisions seems to present ''limiting fragmentation''. In the same energy range, proton-nucleus collisions resemble closely proton-proton collisions and asymmetric shape of rapidities is only caused by the break-up products of heavy targets [fr

New aspects of the atomic nucleus

International Nuclear Information System (INIS)

Wilkinson, D.H.

1987-01-01

We are at last just beginning to identify convincing evidence for what we have long believed, namely that the nucleus is more than the sum of its neutron-proton parts taken pairwise because, for example, a cluster of three nucleons interacts differently from the sum of the interactions of its three pairs; there is an important collectivism in the life of a nucleus even before we ask what its nucleons are doing. (orig./WL)

Advances in hard nucleus cataract surgery

Directory of Open Access Journals (Sweden)

Wei Cui

2013-11-01

Full Text Available Security and perfect vision and fewer complications are our goals in cataract surgery, and hard-nucleus cataract surgery is always a difficulty one. Many new studies indicate that micro-incision phacoemulsification in treating hard nucleus cataract is obviously effective. This article reviews the evolution process of hard nuclear cataract surgery, the new progress in the research of artificial intraocular lens for microincision, and analyse advantages and disadvantages of various surgical methods.

Cytoarchitectonic and quantitative Golgi study of the hedgehog supraoptic nucleus.

Science.gov (United States)

Caminero, A A; Machín, C; Sanchez-Toscano, F

1992-01-01

A cytoarchitectural study was made of the supraoptic nucleus (SON) of the hedgehog with special attention to the quantitative comparison of its main neuronal types. The main purposes were (1) to relate the characteristics of this nucleus in the hedgehog (a primitive mammalian insectivorous brain) with those in the SONs of more evolutionarily advanced species; (2) to identify quantitatively the dendritic fields of the main neuronal types in the hedgehog SON and to study their synaptic connectivity. From a descriptive standpoint, 3 neuronal types were found with respect to the number of dendritic stems arising from the neuronal soma: bipolar neurons (48%), multipolar neurons (45.5%) and monopolar neurons (6.5%). Within the multipolar type 2 subtypes could be distinguished, taking into account the number of dendritic spines: (a) with few spines (93%) and (b) very spiny (7%). These results indicate that the hedgehog SON is similar to that in other species except for the very spiny neurons, the significance of which is discussed. In order to characterise the main types more satisfactorily (bipolar and multipolars with few spines) we undertook a quantitative Golgi study of their dendritic fields. Although the patterns of the dendritic field are similar in both neuronal types, the differences in the location of their connectivity can reflect functional changes and alterations in relation to the synaptic afferences. Images Fig. 2 Fig. 3 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:1452481

Rho GTPases in ameloblast differentiation

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Keishi Otsu

2016-05-01

Full Text Available During tooth development, ameloblasts differentiate from inner enamel epithelial cells to enamel-forming cells by modulating the signal pathways mediating epithelial–mesenchymal interaction and a cell-autonomous gene network. The differentiation process of epithelial cells is characterized by marked changes in their morphology and polarity, accompanied by dynamic cytoskeletal reorganization and changes in cell–cell and cell–matrix adhesion over time. Functional ameloblasts are tall, columnar, polarized cells that synthesize and secrete enamel-specific proteins. After deposition of the full thickness of enamel matrix, ameloblasts become smaller and regulate enamel maturation. Recent significant advances in the fields of molecular biology and genetics have improved our understanding of the regulatory mechanism of the ameloblast cell life cycle, mediated by the Rho family of small GTPases. They act as intracellular molecular switch that transduce signals from extracellular stimuli to the actin cytoskeleton and the nucleus. In our review, we summarize studies that provide current evidence for Rho GTPases and their involvement in ameloblast differentiation. In addition to the Rho GTPases themselves, their downstream effectors and upstream regulators have also been implicated in ameloblast differentiation.

Abnormal resting-state functional connectivity of the left caudate nucleus in obsessive-compulsive disorder.

Science.gov (United States)

Chen, Yunhui; Juhás, Michal; Greenshaw, Andrew J; Hu, Qiang; Meng, Xin; Cui, Hongsheng; Ding, Yongzhuo; Kang, Lu; Zhang, Yubo; Wang, Yuhua; Cui, Guangcheng; Li, Ping

2016-06-03

Altered brain activities in the cortico-striato-thalamocortical (CSTC) circuitry are implicated in the pathophysiology of obsessive-compulsive disorder (OCD). However, whether the underlying changes occur only within this circuitry or in large-scale networks is still not thoroughly understood. This study performed voxel-based functional connectivity analysis on resting-state functional magnetic resonance imaging (fMRI) data from thirty OCD patients and thirty healthy controls to investigate whole-brain intrinsic functional connectivity patterns in OCD. Relative to the healthy controls, OCD patients showed decreased functional connectivity within the CSTC circuitry but increased functional connectivity in other brain regions. Furthermore, decreased left caudate nucleus-thalamus connectivity within the CSTC circuitry was positively correlated with the illness duration of OCD. This study provides additional evidence that CSTC circuitry may play an essential role and alteration of large-scale brain networks may be involved in the pathophysiology of OCD. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Afferent projections to the deep mesencephalic nucleus in the rat

International Nuclear Information System (INIS)

Veazey, R.B.; Severin, C.M.

1982-01-01

Afferent projections to the deep mesencephalic nucleus (DMN) of the rat were demonstrated with axonal transport techniques. Potential sources for projections to the DMN were first identified by injecting the nucleus with HRP and examining the cervical spinal cord, brain stem, and cortex for retrogradely labeled neurons. Areas consistently labeled were then injected with a tritiated radioisotope, the tissue processed for autoradiography, and the DMN examined for anterograde labeling. Afferent projections to the medial and/or lateral parts of the DMN were found to originate from a number of spinal, bulbar, and cortical centers. Rostral brain centers projecting to both medial and lateral parts of the DMN include the ipsilateral motor and somatosensory cortex, the entopeduncular nucleus, and zona incerta. at the level of the midbrain, the ipsilateral substantia nigra and contralateral DMN likewise project to the DMN. Furthermore, the ipsilateral superior colliculus projects to the DMN, involving mainly the lateral part of the nucleus. Afferents from caudal centers include bilateral projections from the sensory nucleus of the trigeminal complex and the nucleus medulla oblongata centralis, as well as from the contralateral dentate nucleus. The projections from the trigeminal complex and nucleus medullae oblongatae centralis terminate in the intermediate and medial parts of the DMN, whereas projections from the contralateral dentate nucleus terminate mainly in its lateral part. In general, the afferent connections of the DMN arise from diverse areas of the brain. Although most of these projections distribute throughout the entire extent of the DMN, some of them project mainly to either medial or lateral parts of the nucleus, thus suggesting that the organization of the DMN is comparable, at least in part, to that of the reticular formation of the pons and medulla, a region in which hodological differences between medial and lateral subdivisions are known to exist

High-energy elastic and quasi-elastic deuteron-nucleus scattering

International Nuclear Information System (INIS)

Tekou, Amouzou

1974-01-01

A study is made of deuteron-nucleus elastic and quasi-elastic scattering and the connection between the opaque nucleus model and the Glauber model is pointed out. The contributions to different cross-sections of the collisions in which the nucleus, excited by one of the nucleons of the deuteron, is brought back to the ground state by the other nucleon is analysed. Coherent deuteron disintegration is found to be highly improbable when the target nucleus is heavy and incoherent disintegration accounts for nearly all the deuteron disintegration. Thus a correct comparison between theoretical and experimental data on proton stripping must take the incoherent deuteron disintegration into consideration

Attributed relational graphs for cell nucleus segmentation in fluorescence microscopy images.

Science.gov (United States)

Arslan, Salim; Ersahin, Tulin; Cetin-Atalay, Rengul; Gunduz-Demir, Cigdem

2013-06-01

More rapid and accurate high-throughput screening in molecular cellular biology research has become possible with the development of automated microscopy imaging, for which cell nucleus segmentation commonly constitutes the core step. Although several promising methods exist for segmenting the nuclei of monolayer isolated and less-confluent cells, it still remains an open problem to segment the nuclei of more-confluent cells, which tend to grow in overlayers. To address this problem, we propose a new model-based nucleus segmentation algorithm. This algorithm models how a human locates a nucleus by identifying the nucleus boundaries and piecing them together. In this algorithm, we define four types of primitives to represent nucleus boundaries at different orientations and construct an attributed relational graph on the primitives to represent their spatial relations. Then, we reduce the nucleus identification problem to finding predefined structural patterns in the constructed graph and also use the primitives in region growing to delineate the nucleus borders. Working with fluorescence microscopy images, our experiments demonstrate that the proposed algorithm identifies nuclei better than previous nucleus segmentation algorithms.

[Algorithm of toxigenic genetically altered Vibrio cholerae El Tor biovar strain identification].

Science.gov (United States)

Smirnova, N I; Agafonov, D A; Zadnova, S P; Cherkasov, A V; Kutyrev, V V

2014-01-01

Development of an algorithm of genetically altered Vibrio cholerae biovar El Tor strai identification that ensures determination of serogroup, serovar and biovar of the studied isolate based on pheno- and genotypic properties, detection of genetically altered cholera El Tor causative agents, their differentiation by epidemic potential as well as evaluation of variability of key pathogenicity genes. Complex analysis of 28 natural V. cholerae strains was carried out by using traditional microbiological methods, PCR and fragmentary sequencing. An algorithm of toxigenic genetically altered V. cholerae biovar El Tor strain identification was developed that includes 4 stages: determination of serogroup, serovar and biovar based on phenotypic properties, confirmation of serogroup and biovar based on molecular-genetic properties determination of strains as genetically altered, differentiation of genetically altered strains by their epidemic potential and detection of ctxB and tcpA key pathogenicity gene polymorphism. The algorithm is based on the use of traditional microbiological methods, PCR and sequencing of gene fragments. The use of the developed algorithm will increase the effectiveness of detection of genetically altered variants of the cholera El Tor causative agent, their differentiation by epidemic potential and will ensure establishment of polymorphism of genes that code key pathogenicity factors for determination of origins of the strains and possible routes of introduction of the infection.

Registration and Analysis of Bioelectric Activity of Sensory-Motor Cortex During the Electrical Stimulation of Nucleus Caudate in Rats

Directory of Open Access Journals (Sweden)

Snežana Medenica-Milanović

2007-05-01

Full Text Available Background and purposeThe caudate circuit takes part in cognitive control of motor activity The purpose of the present work was registration and analysis of basic bioelectrical activity of ventral and dorsal sensory-motor cortex and nucleus caudate, study of the changes in EEG after nucleus caudate electrical stimulation and to identify of threshold level of electrical stimuli responsible for changes of electrical activity in registered brain area.Materials and methodsWe used 28 albino Wistar rat of both genders. After the animal fixation on stereotaxic apparatus to dry bone, the places for electrode fixation were marked. Two days after the electrodes had been implanted an EEG was registered so that the animals would adjust to the conditions and so they would repair the tissue reactions. EEG was registered with bipolar electrodes with ten-channeled apparatus. For first half an hour spontaneous activity of the brain was registered, and after that the head of nucleus caudate was stimulated with altered impulses of various voltages, frequency and duration.Results and conclusionsThreshold values of electric stimulus intensity from 3 to 5 V, frequency from 3 to 5 Hz, duration from 3 to 5 ms, by stimulation the head of nucleus caudate of rat, lead to the change of basal bioelectric activity of cerebrum. The change of bioelectric activity is firstly recorded in equilateral cortex, and with the higher intensity of the stimulus the changes overtake the contra lateral cortex.

High-throughput sperm differential proteomics suggests that epigenetic alterations contribute to failed assisted reproduction.

Science.gov (United States)

Azpiazu, Rubén; Amaral, Alexandra; Castillo, Judit; Estanyol, Josep Maria; Guimerà, Marta; Ballescà, Josep Lluís; Balasch, Juan; Oliva, Rafael

2014-06-01

Are there quantitative alterations in the proteome of normozoospermic sperm samples that are able to complete IVF but whose female partner does not achieve pregnancy? Normozoospermic sperm samples with different IVF outcomes (pregnancy versus no pregnancy) differed in the levels of at least 66 proteins. The analysis of the proteome of sperm samples with distinct fertilization capacity using low-throughput proteomic techniques resulted in the detection of a few differential proteins. Current high-throughput mass spectrometry approaches allow the identification and quantification of a substantially higher number of proteins. This was a case-control study including 31 men with normozoospermic sperm and their partners who underwent IVF with successful fertilization recruited between 2007 and 2008. Normozoospermic sperm samples from 15 men whose female partners did not achieve pregnancy after IVF (no pregnancy) and 16 men from couples that did achieve pregnancy after IVF (pregnancy) were included in this study. To perform the differential proteomic experiments, 10 no pregnancy samples and 10 pregnancy samples were separately pooled and subsequently used for tandem mass tags (TMT) protein labelling, sodium dodecyl sulphate-polyacrylamide gel electrophoresis, liquid chromatography tandem mass spectrometry (LC-MS/MS) identification and peak intensity relative protein quantification. Bioinformatic analyses were performed using UniProt Knowledgebase, DAVID and Reactome. Individual samples (n = 5 no pregnancy samples; n = 6 pregnancy samples) and aliquots from the above TMT pools were used for western blotting. By using TMT labelling and LC-MS/MS, we have detected 31 proteins present at lower abundance (ratio no pregnancy/pregnancy 1.5) in the no pregnancy group. Bioinformatic analyses showed that the proteins with differing abundance are involved in chromatin assembly and lipoprotein metabolism (P values Economia y Competividad; FEDER BFU 2009-07118 and PI13/00699) and

GABAergic projections to the oculomotor nucleus in the goldfish (Carassius auratus

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M. Angeles eLuque

2011-02-01

Full Text Available The mammalian oculomotor nucleus receives a strong -aminobutyric acid (GABAergic synaptic input, whereas such projections have rarely been reported in fish. In order to determine whether this synaptic organization is preserved across vertebrates, we investigated the GABAergic projections to the oculomotor nucleus in the goldfish by combining retrograde transport of biotin dextran amine, injected into the antidromically identified oculomotor nucleus, and GABA immunohistochemistry. The main source of GABAergic afferents to the oculomotor nucleus was the ipsilateral anterior octaval nucleus, with only a few, if any, GABAergic neurons being located in the contralateral tangential and descending nuclei of the octaval column. In mammals there is a nearly exclusive ipsilateral projection from vestibular neurons to the oculomotor nucleus via GABAergic inhibitory inputs; thus, the vestibulooculomotor GABAergic circuitry follows a plan that appears to be shared throughout the vertebrate phylogeny. The second major source of GABAergic projections was the rhombencephalic reticular formation, primarily from the medial area but, to a lesser extent, from the inferior area. A few GABAergic oculomotor projecting neurons were also observed in the ipsilateral nucleus of the medial longitudinal fasciculus. The GABAergic projections from neurons located in both the reticular formation surrounding the abducens nucleus and the nucleus of the medial reticular formation have primarily been related to the control of saccadic eye movements. Finally, all retrogradely labeled internuclear neurons of the abducens nucleus, and neurons in the cerebellum (close to the caudal lobe, were negative for GABA. These data suggest that the vestibuloocular and saccadic inhibitory GABAergic systems appear early in vertebrate phylogeny to modulate the firing properties of the oculomotor nucleus motoneurons.

Qualitative analysis neurons in the adult human dentate nucleus

Directory of Open Access Journals (Sweden)

Marić Dušica

2012-01-01

Full Text Available Although many relevant findings regarding to the morphology and cytoarchitectural development of the dentate nucleus have been presented so far, very little qualitative information has been collected on neuronal morphology in the adult human dentate nucleus. The neurons were labelled by Golgi staining from thirty human cerebella, obtained from medico-legal forensic autopsies of adult human bodies and free of significant brain pathology. The human dentate neurons were qualitatively analyzed and these cells were classified into two main classes: the small and the large multipolar neurons. Considering the shape of the cell body, number of the primary dendrites, shape of the dendritic tree and their position within the dentate nucleus, three subclasses of the large multipolar neurons have been recognized. The classification of neurons from the human dentate nucleus has been qualitatively confirmed in fetuses and premature infants. This study represents the first qualitative analysis and classification of the large multipolar neurons in the dentate nucleus of the adult human.

Correlations between projectile and target breakup: a comparative study of nucleus-nucleus collisions at 75, 175 and 2000A MeV

International Nuclear Information System (INIS)

Bjarle, C.; Herrstroem, N.Y.; Kullberg, R.; Oskarsson, A.; Otterlund, I.

1982-01-01

Nucleus-nucleus collision in three different energy intervals: 50-100, 150-200 and 1900-2100A MeV have been studied in nuclear emulsion. The reactions were 16 O + average emulsion target (H, C, N, O, Ag, Br). In each event, all emitted charged particles were recorded, projectile fragments with Z>=2 identifed and the number of charged particles from the target nucleus was determined. The results are discussed in terms of the geometrical aspects of Heavy Ion collisions and direct comparisons are made with the Coldhaber fragmentation model

Meal frequency differentially alters postprandial triacylglycerol and insulin concentrations in obese women.

Science.gov (United States)

Heden, Timothy D; Liu, Ying; Sims, Lauren J; Whaley-Connell, Adam T; Chockalingam, Anand; Dellsperger, Kevin C; Kanaley, Jill A

2013-01-01

The aim of this study was to compare postprandial lipemia, oxidative stress, antioxidant activity, and insulinemia between a three and six isocaloric high-carbohydrate meal frequency pattern in obese women. In a counterbalanced order, eight obese women completed two, 12-h conditions in which they consumed 1,500 calories (14% protein, 21% fat, and 65% carbohydrate) either as three 500 calorie liquid meals every 4-h or six 250 calorie liquid meals every 2-h. Blood samples were taken every 30 min and analyzed for triacylglycerol (TAG), total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, oxidized low-density lipoprotein cholesterol, myeloperoxidase, paraoxonase-1 activity, and insulin. The TAG incremental area under the curve (iAUC) during the three meal condition (321 ± 129 mg/dl · 12 h) was significantly lower (P = 0.04) compared with the six meal condition (481 ± 155 mg/dl · 12 h). The insulin iAUC during the three meal condition (5,549 ± 1,007 pmol/l · 12 h) was significantly higher (P = 0.05) compared with the six meal condition (4,230 ± 757 pmol/l(.) 12 h). Meal frequency had no influence on the other biochemical variables. Collectively, a three and six isocaloric high-carbohydrate meal frequency pattern differentially alters postprandial TAG and insulin concentrations but has no effect on postprandial cholesterol, oxidative stress, or antioxidant activity in obese women. Copyright © 2012 The Obesity Society.

FoxC2 Enhances BMP7-Mediated Anabolism in Nucleus Pulposus Cells of the Intervertebral Disc

OpenAIRE

Wang, Zheng; Fu, Changfeng; Chen, Yong; Xu, Feng; Wang, Zhenyu; Qu, Zhigang; Liu, Yi

2016-01-01

Bone-morphogenetic protein-7 (BMP-7) is a growth factor that plays a major role in mediating anabolism and anti-catabolism of the intervertebral disc matrix and cell homeostasis. In osteoblasts, Forkhead box protein C2 (FoxC2) is a downstream target of BMPs and promotes cell proliferation and differentiation. However, the role FoxC2 may play in degenerative human intervertebral disc tissue and the relationship between FoxC2 and BMP-7 in nucleus pulposus (NP) cells remain to be elucidated. Thi...

3D Protein Dynamics in the Cell Nucleus.

Science.gov (United States)

Singh, Anand P; Galland, Rémi; Finch-Edmondson, Megan L; Grenci, Gianluca; Sibarita, Jean-Baptiste; Studer, Vincent; Viasnoff, Virgile; Saunders, Timothy E

2017-01-10

The three-dimensional (3D) architecture of the cell nucleus plays an important role in protein dynamics and in regulating gene expression. However, protein dynamics within the 3D nucleus are poorly understood. Here, we present, to our knowledge, a novel combination of 1) single-objective based light-sheet microscopy, 2) photoconvertible proteins, and 3) fluorescence correlation microscopy, to quantitatively measure 3D protein dynamics in the nucleus. We are able to acquire >3400 autocorrelation functions at multiple spatial positions within a nucleus, without significant photobleaching, allowing us to make reliable estimates of diffusion dynamics. Using this tool, we demonstrate spatial heterogeneity in Polymerase II dynamics in live U2OS cells. Further, we provide detailed measurements of human-Yes-associated protein diffusion dynamics in a human gastric cancer epithelial cell line. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Nucleus-Nucleus Scattering in the High-Energy Approximation and the Optical Folding Potential

CERN Document Server

Lukyanov, V K; Lukyanov, K V

2004-01-01

For the nucleus-nucleus scattering, the complex potential is obtained which corresponds to the eikonal phase of an optical limit of the Glauber-Sitenko high-energy approximation. The potential does not include free parameters, its real and imaginary parts depend on energy and are determined by the reported data on the nuclear density distributions and nucleon-nucleon scattering amplitude. Alternatively, for the real part, the folding potential can be utilized which includes the effective NN-forces and the exchange term, as well. As a result, the microscopic optical potential is constructed where contributions of the calculated real and imaginary parts are formed by fitting the two respective factors. An efficient of the approach is confirmed by agreements of calculations with the experimental data on elastic scattering cross-sections.

Formin' actin in the nucleus.

Science.gov (United States)

Baarlink, Christian; Grosse, Robert

2014-01-01

Many if not most proteins can, under certain conditions, change cellular compartments, such as, for example, shuttling from the cytoplasm to the nucleus. Thus, many proteins may exert functions in various and very different subcellular locations, depending on the signaling context. A large amount of actin regulatory proteins has been detected in the mammalian cell nucleus, although their potential roles are much debated and are just beginning to emerge. Recently, members of the formin family of actin nucleators were also reported to dynamically localize to the nuclear environment. Here we discuss our findings that specific diaphanous-related formins can promote nuclear actin assembly in a signal-dependent manner.

On the geometric nature of high energy nucleus-nucleus reaction cross sections

International Nuclear Information System (INIS)

Townsend, L.W.; Wilson, J.W.; Bidasaria, H.B.

1982-01-01

Within the context of a high energy double-folding optical potential approximation to the exact nucleus-nucleus multiple-scattering series, eikonal scattering theory is used to investigate the validity of geometric reaction cross sections in relativistic heavy ion collisions. The potential used includes a finite range interaction and nuclear single-particle densities extracted from nuclear charge distributions by unfolding the proton charge distribution. Pauli correlation effects are also included in an approximate way. The sensitivity of the predictions to be assumed interaction, Pauli correlation approximation, and nuclear density distributions is investigated. These results are in agreement with early predictions concerning the geometric nature of relativistic heavy ion collisions and in disagreement with a recent analysis, utilizing the zero range approximation, which suggested otherwise. Reasons for the lack of agreement between the analyses are also presented. Finally, approximate applicability for geometric reaction cross sections are determined

Study of various models of nuclear interaction potentials: nucleon-nucleus and nucleus-nucleus systems

International Nuclear Information System (INIS)

Ngo, H.

1984-01-01

Several models, performed within a mean field theory, are developed for the calculation of nucleon-nucleus interaction potentials. The first part of the thesis deals with the nucleon-nucleus average interaction. It is mainly devoted to the calculation of dynamical corrections to the Hartree-Fock approximation. Two approaches are used: a microscopic model performed in the framework of the nuclear structure approach and a semi-phenomenological one, based on the application of the dispersion relations to the empirical imaginary potential. Both models take into account finite size effects like collectivity or threshold effects which are important at low energy. The Green's function properties are used for both models. The second part of this work is devoted to the interaction potential between two heavy ions. This calculation, which is performed in the framework of the sudden approximation, uses the energy density formalism (Thomas-Fermi approximation). It has been extended to finite temperature. At T=0 the experimental fusion barriers of heavy systems are reproduced within 4%. Their temperature dependence is studied. The proximity scaling is checked and a universal function is obtained at T=0 and at finite temperature. It is found that the proximity theorem is well satisfied on the average. The dispersion around the mean behaviour increases with increasing temperature. At last, P+A* and α+A* interaction potentials are calculated within a double folding model using a schematic effective interaction [fr

Nucleus fingerprinting for the unique identification of Feulgen-stained nuclei

Science.gov (United States)

Friedrich, David; Brozio, Matthias; Bell, André; Biesterfeld, Stefan; Böcking, Alfred; Aach, Til

2012-03-01

DNA Image Cytometry is a method for non-invasive cancer diagnosis which measures the DNA content of Feulgen-stained nuclei. DNA content is measured using a microscope system equipped with a digital camera as a densitometer and estimating the DNA content from the absorption of light when passing through the nuclei. However, a DNA Image Cytometry measurement is only valid if each nucleus is only measured once. To assist the user in preventing multiple measurements of the same nucleus, we have developed a unique digital identifier for the characterization of Feulgen-stained nuclei, the so called Nucleus Fingerprint. Only nuclei with a new fingerprint can be added to the measurement. This fingerprint is based on basic nucleus features, the contour of the nucleus and the spatial relationship to nuclei in the vicinity. Based on this characterization, a classifier for testing two nuclei for identity is presented. In a pairwise comparison of ~40000 pairs of mutually different nuclei, 99.5% were classified as different. In another 450 tests, the fingerprints of the same nucleus recorded a second time were in all cases judged identical. We therefore conclude that our Nucleus Fingerprint approach robustly prevents the repeated measurement of nuclei in DNA Image Cytometry.

Study of η-nucleus interaction through the formation of η-nucleus ...

Indian Academy of Sciences (India)

Abstract. The question of possible existence of η-mesic nuclei is quite intriguing. An- swer to this question will deeply enrich our understanding of η-nucleus interaction which is not so well-understood. We review the experimental efforts for the search of η-mesic nuclei and describe the physics motivation behind it.

High energy cosmic ray events of ultra-relativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Burnett, T.H.; Dake, S.; Derricson, J.H.; Fountain, W.; Fuki, M.; Gregory, J.C.; Hayashi, T.; Hayashi, T.; Holynski, R.; Iwai, J.; Jones, W.V.; Jurak, A.; Lord, J.J.; Meegan, C.A.; Miyamura, O.; Oda, H.; Ogata, T.; Parnell, T.A.; Roberts, E.; Saito, T.; Strauss, S.; Tabuki, T.; Takahashi, Y.; Tominaga, T.; Watts, J.W.; Wilczynska, B.; Wilkes, R.J.; Wolter, W.; Bosiek, B.

1985-01-01

Japanese American Cooperative Emulsion Experiment (JACEE) has been measuring ultrarelativistic comic ray nucleus and sampling the events in the energy regions both 10 to 100 GeV/A and above TeV/A by balloon emulsion chamber since 1979. In this report main results obtained up to now will be described. (orig./HSI)

Analysis of the thematic content of review Nucleus

International Nuclear Information System (INIS)

Guerra Valdes, Ramiro

2007-01-01

A computer programme for performing standardized analysis of research areas and key concepts of nuclear science and technology under development at Cubaenergia is presented. Main components of the information processing system, as well as computational methods and modules for thematic content analysis of INIS Database record files are described. Results of thematic content analysis of review Nucleus from 1986 to 2005 are shown. Furthermore, results of demonstrative study Nucleus, Science, Technology and Society are also shown. The results provide new elements to asses the significance of the thematic content of review Nucleus in the context of innovation in interrelated multidisciplinary research areas

Inclusive prompt photon production in electron-nucleus scattering at small x

Science.gov (United States)

Roy, Kaushik; Venugopalan, Raju

2018-05-01

We compute the differential cross-section for inclusive prompt photon production in deeply inelastic scattering (DIS) of electrons on nuclei at small x in the framework of the Color Glass Condensate (CGC) effective theory. The leading order (LO) computation in this framework resums leading logarithms in x as well as power corrections to all orders in Q s, A 2 / Q 2, where Q s, A ( x) is the nuclear saturation scale. This LO result is proportional to universal dipole and quadrupole Wilson line correlators in the nucleus. In the soft photon limit, the Low-Burnett-Kroll theorem allows us to recover existing results on inclusive DIS dijet production. The k ⊥ and collinearly factorized expressions for prompt photon production in DIS are also recovered in a leading twist approximation to our result. In the latter case, our result corresponds to the dominant next-to-leading order (NLO) perturbative QCD contribution at small x. We next discuss the computation of the NLO corrections to inclusive prompt photon production in the CGC framework. In particular, we emphasize the advantages for higher order computations in inclusive photon production, and for fully inclusive DIS, arising from the simple momentum space structure of the dressed quark and gluon "shock wave" propagators in the "wrong" light cone gauge A - = 0 for a nucleus moving with P N + → ∞.

Estimation of nuclear destruction in high energy nucleus-nucleus interactions

International Nuclear Information System (INIS)

Uzhinskij, V.V.

1995-01-01

It is assumed that: 1) a projectile particle invokes into target nucleus a cascade of quark-gluon exchanges; 2) the nucleons involved in the cascade are ejected from the nucleus which leads to the nuclear destruction. On these bases a simple model to estimate the nuclear destruction at the fast stage of the interaction is proposed. The allowed region of the model parameters is determined at the proton-emulsion high-energy interaction data analysis: an analysis of gold interactions with nuclei at an energy of 600 MeV/nucleon fixes the parameter values. The distributions on the energy in zero degree calorimeter (T ZDC ) in the interactions of Si+Al, Cu, Pb (14 GeV/nucleon) and Au+Au (10 GeV/nucleon) calculated in the framework of the model and in the cascade-evaporation model (CEM) are presented. The proposed model describes the nuclear destruction at intermediate and high energies better than CEM does. The estimation of the average values of impact parameter and the number of intra-nuclear collisions for Au+Au interactions in the events with different T ZDC is given. 34 refs., 11 figs

A-dependence of differential multiplicity at 7 GeV/c

International Nuclear Information System (INIS)

Arefyev, A.V.; Bayukov, Yu.D.; Efremenko, V.I.

1977-01-01

Particle production in the inelastic proton-nucleus interactions have been investigated at the initial momentum psub(0)=7 GeV/c for Be, Al, C, Cu, Cd and Pb nuclei. A-dependences of both π - and p differential multiplicities are parametrized as approximately Asup(α(sub(i)))i. Similar parametrization seems to be also suitable for the normalized topological cross-section Wsup(n-)(A) of the processes with nsup(-) forward emitted negative pions. The dependence of αsub(i) on the secondary particle type and its kinematic region for (A) and on n - for Wsup(n-)(A) has been obtained. These experimental data indicate to secondary interactions of the produced particles inside nucleus. The total multiplicity distribution is observed to obey KNO scaling

On studies of the hadron-nucleus collision processes

International Nuclear Information System (INIS)

Strugalski, Z.

1992-01-01

A new way of hadron-nucleus collision process investigations in experiments is described. It is based on the properties of the hadron passage through layers of the intranuclear matter. The picture of the hadron-nucleus collision mechanism, as prompted experimentally, is presented. 37 refs.; 1 tab

Antiproton-nucleus interaction

International Nuclear Information System (INIS)

Gibbs, W.R.

1984-01-01

Several facets of antinucleon-nucleus interactions are explored. The topics treated are: coherent interactions, production of unusual states and particles in the nuclear medium, and the creation of extreme states of matter by antimatter annihilation. It is found that temperatures of the magnitude necessary to achieve the predicted quark-gluon phase transition are obtained. 20 references

Testing string dynamics in lepton nucleus reactions

International Nuclear Information System (INIS)

Gyulassy, M.; Pluemer, M.

1989-10-01

The sensitivity of nuclear attenuation of 10-100 GeV lepton nucleus (ell A) reactions to space-time aspects of hadronization is investigated within the context of the Lund string model. We consider two mechanisms for attenuation in a nucleus: final state cascading and string flip excitations. Implications for the evolution of the energy density in nuclear collisions are discussed. 16 refs., 10 figs

Inclusive jet production in ultrarelativistic proton-nucleus collisions

CERN Document Server

Perepelitsa, Dennis

High-$p_\\mathrm{T}$ processes in proton- and deuteron-nucleus collisions at TeV energies are the best presently available way to study the partonic structure of the nucleus in a high-density regime. Jet production over a wide range of phase space can significantly constrain the current knowledge of nuclear parton distribution functions (nPDFs), which are substantially less well understood than the corresponding PDFs in protons and which have only recently begun to be treated in a spatially-dependent way. An accurate knowledge of nPDFs is crucial for a definitive control of perturbative processes in a cold nuclear environment, since high-$p_\\mathrm{T}$ probes are used to quantitatively investigate the hot QCD matter created in ultrarelativistic nucleus-nucleus collisions. Furthermore, jets from low Bjorken-$x$ partons can probe the transition from the dilute to saturated nuclear regimes. Jet production is investigated in $d$+Au collisions at $\\sqrt{s} = 200$ GeV with the PHENIX detector at the Relativistic Hea...

Nucleus accumbens and impulsivity

NARCIS (Netherlands)

Basar, K.; Sesia, T.; Groenewegen, H.J.; Steinbusch, H.W.; Visser-vandewalle, V.; Temel, Y.

2010-01-01

The multifaceted concept of impulsivity implies that different impulsivity aspects, mediated by different neural processes, influence behavior at different levels. The nucleus accumbens (NAc) is a key component of the neural processes regulating impulsivity. In this review, we discuss the findings

Differential behavioral profile induced by the injection of dipotassium chlorazepate within brain areas that project to the nucleus accumbens septi.

Science.gov (United States)

Llano López, Luis H; Caif, Fernando; Fraile, Miriam; Tinnirello, Belén; de Gargiulo, Adriana I Landa; Lafuente, José V; Baiardi, Gustavo C; Gargiulo, Pascual A

2013-01-01

The effect of the agonism on γ-aminobutyric acid (GABA) receptors was studied within medial prefrontal cortex (mPFC), amygdala (AMY) and ventral hipocampus (VH) in the plus-maze test in male rats bilaterally cannulated. These structures send glutamatergic projections to the nucleus accumbens septi (NAS), in which interaction and integration between these afferent pathways has been described. In a previous study of our group, blockade of glutamatergic transmission within NAS induced an anxiolytic like effect. Three rat groups received either saline or dipotassium chlorazepate (1 or 2 μg/1 μl solution) 15 min before testing. Time spent in the open arms (TSOA), time per entry (TPE), extreme arrivals (EA), open and closed arms entries (OAE, CAE) and relationship between open- and closed-arms quotient (OCAQ) were recorded. In the AMY injected group TSOA, OAE and EA were increased by the higher doses of dipotassium chlorazepate (p < 0.01). In the mPFC, TPE was decreased by both doses (p < 0.05). Injection within ventral hippocampus (VH) decreased TSOA, OAE and OCAQ with lower doses (p < 0.05). When the three studied saline groups were compared, TSOA, OAE, EA and OCAQ were enhanced in the VH group when compared to mPFC and AMY (p < 0.001). Insertion of inner canula (p < 0.001, p < 0.01, p < 0.01) and saline injection showed an increasing significant difference (p < 0.001 in all cases) with the action of guide cannula alone within VH in TSOA, OAE and EA. We conclude that the injection of dipotassium chlorazepate has a differential effect depending of the brain area, leading to facilitatory and inhibitory effects on anxiety processing.

Mechanism of energy release from nucleus-target in hadron-nucleus collision

International Nuclear Information System (INIS)

Strugalski, Z.; Strugalska-Gola, E.

2000-01-01

The collisions of hadrons (protons, mesons) with 131 Xe nucleus and arising light nuclear fragments as nuclear refraction products have been observed in bubble chamber. Mechanism of energy release during these collisions has been discussed. The quantitative calculations has proved that this phenomena can be treated as potential energy source with use of many different target materials

Intracellular fragment of NLRR3 (NLRR3-ICD) stimulates ATRA-dependent neuroblastoma differentiation

International Nuclear Information System (INIS)

Akter, Jesmin; Takatori, Atsushi; Islam, Md. Sazzadul; Nakazawa, Atsuko; Ozaki, Toshinori; Nagase, Hiroki; Nakagawara, Akira

2014-01-01

Highlights: • NLRR3 is a membrane protein highly expressed in favorable neuroblastoma. • NLRR3-ICD was produced through proteolytic processing by secretases. • NLRR3-ICD was induced to be translocated into cell nucleus following ATRA exposure. • NLRR3-ICD plays a pivotal role in ATRA-mediated neuroblastoma differentiation. - Abstract: We have previously identified neuronal leucine-rich repeat protein-3 (NLRR3) gene which is preferentially expressed in favorable human neuroblastomas as compared with unfavorable ones. In this study, we have found for the first time that NLRR3 is proteolytically processed by secretases and its intracellular domain (NLRR3-ICD) is then released to translocate into cell nucleus during ATRA-mediated neuroblastoma differentiation. According to our present observations, NLRR3-ICD was induced to accumulate in cell nucleus of neuroblastoma SH-SY5Y cells following ATRA treatment. Since the proteolytic cleavage of NLRR3 was blocked by α- or γ-secretase inhibitor, it is likely that NLRR3-ICD is produced through the secretase-mediated processing of NLRR3. Intriguingly, forced expression of NLRR3-ICD in neuroblastoma SK-N-BE cells significantly suppressed their proliferation as examined by a live-cell imaging system and colony formation assay. Similar results were also obtained in neuroblastoma TGW cells. Furthermore, overexpression of NLRR3-ICD stimulated ATRA-dependent neurite elongation in SK-N-BE cells. Together, our present results strongly suggest that NLRR3-ICD produced by the secretase-mediated proteolytic processing of NLRR3 plays a crucial role in ATRA-mediated neuronal differentiation, and provide a clue to develop a novel therapeutic strategy against aggressive neuroblastomas

Intracellular fragment of NLRR3 (NLRR3-ICD) stimulates ATRA-dependent neuroblastoma differentiation

Energy Technology Data Exchange (ETDEWEB)

Akter, Jesmin [Laboratory of Innovative Cancer Therapeutics, Chiba Cancer Center Research Institute, Chiba 260-8717 (Japan); Takatori, Atsushi, E-mail: atakatori@chiba-cc.jp [Laboratory of Cancer Genetics, Chiba Cancer Center Research Institute, Chiba 260-8717 (Japan); Islam, Md. Sazzadul [Laboratory of Innovative Cancer Therapeutics, Chiba Cancer Center Research Institute, Chiba 260-8717 (Japan); Nakazawa, Atsuko [Department of Pathology, National Center for Child Health and Development, Tokyo (Japan); Ozaki, Toshinori, E-mail: tozaki@chiba-cc.jp [Laboratory of DNA Damage Signaling, Chiba Cancer Center Research Institute, Chiba 260-8717 (Japan); Nagase, Hiroki [Laboratory of Cancer Genetics, Chiba Cancer Center Research Institute, Chiba 260-8717 (Japan); Nakagawara, Akira [Saga Medical Centre, 840-8571 (Japan)

2014-10-10

Highlights: • NLRR3 is a membrane protein highly expressed in favorable neuroblastoma. • NLRR3-ICD was produced through proteolytic processing by secretases. • NLRR3-ICD was induced to be translocated into cell nucleus following ATRA exposure. • NLRR3-ICD plays a pivotal role in ATRA-mediated neuroblastoma differentiation. - Abstract: We have previously identified neuronal leucine-rich repeat protein-3 (NLRR3) gene which is preferentially expressed in favorable human neuroblastomas as compared with unfavorable ones. In this study, we have found for the first time that NLRR3 is proteolytically processed by secretases and its intracellular domain (NLRR3-ICD) is then released to translocate into cell nucleus during ATRA-mediated neuroblastoma differentiation. According to our present observations, NLRR3-ICD was induced to accumulate in cell nucleus of neuroblastoma SH-SY5Y cells following ATRA treatment. Since the proteolytic cleavage of NLRR3 was blocked by α- or γ-secretase inhibitor, it is likely that NLRR3-ICD is produced through the secretase-mediated processing of NLRR3. Intriguingly, forced expression of NLRR3-ICD in neuroblastoma SK-N-BE cells significantly suppressed their proliferation as examined by a live-cell imaging system and colony formation assay. Similar results were also obtained in neuroblastoma TGW cells. Furthermore, overexpression of NLRR3-ICD stimulated ATRA-dependent neurite elongation in SK-N-BE cells. Together, our present results strongly suggest that NLRR3-ICD produced by the secretase-mediated proteolytic processing of NLRR3 plays a crucial role in ATRA-mediated neuronal differentiation, and provide a clue to develop a novel therapeutic strategy against aggressive neuroblastomas.

Nucleus of Comet IRAS-Araki-Alcock (1983 VII)

International Nuclear Information System (INIS)

Sekanina, Z.

1988-01-01

Optical, radar, infrared, UV, and microwave-continuum observations of Comet IRAS-Araki-Alcok were obtained in May 1983, the week of the comet's close approach to earth. The comet has a nucleus dimension and a rotation period which are similar to those of Comet Halley, but a different morphological signature (a persisting sunward fan-shaped coma). Time variations are noted in the projected nucleus cross section. Results suggest significant limb-darkening effects in the relevant domains of radio waves, and that the comet's interior must be extremely cold. It is found that the thermal-infrared fluxes from the inner coma of the comet are dominated by the nucleus. 63 references

On slow particle production in hadron-nucleus interactions

International Nuclear Information System (INIS)

Stenlund, E.; Otterlund, I.

1982-01-01

A model for slow particle production in hadron-nucleus interactions is presented. The model succesfully predicts correlations between the number of knock-on particles and the number of particles associated with the evaporation process as well as correlations with the number of collisions, ν, between the incident hadron and the nucleons inside the target nucleus. The model provides two independent possibilities to determine the number of primary intranuclear collisions, ν, i.e. by its correlation to the number of knock-on particles or to the number of evaporated particles. The good agreement indicates that the model gives an impact-parameter sensitive description of hardron nucleus reactions. (orig.)

Multifragmentation in peripheral nucleus-nucleus collisions

International Nuclear Information System (INIS)

Trautmann, W.; Adloff, J.C.; Bouissou, P.; Hubele, J.; Imme, G.; Iori, I.; Kreutz, P.; Leray, S.; Lindenstruth, V.; Liu, Z.; Lynen, U.; Meijer, R.J.; Milkau, U.; Moroni, A.; Mueller, W.F.J.; Ngo, C.; Ogilvie, C.A.; Pochodzalla, J.; Raciti, G.; Rudolf, G.; Schuettauf, A.; Stuttge, L.

1993-10-01

The complete fragmentation of highly excited nuclear systems into fragments of intermediate mass is observed in heavy-ion reactions at relativistic bombarding energies in the range of several hundreds of MeV per nucleon. Similar features are found for peripheral collisions between heavy nuclei and for more central collisions between a heavy and a light nucleus. The partition space explored in multifragment decays is well described by the statistical multifragmentation models. The expansion before breakup is confirmed by the analysis of the measured fragment energies of ternary events in their own rest frame. Collective radial flow is confined to rather small values in these peripheral-type reactions. Many conceptually different models seem to be capable of reproducing the charge correlations measured for the multifragment decays. (orig.)

Finite element study of a lumbar intervertebral disc nucleus replacement device

Directory of Open Access Journals (Sweden)

Jessica S Coogan

2016-12-01

Full Text Available Nucleus replacement technologies are a minimally invasive alternative to spinal fusion and total disc replacement that have the potential to reduce pain and restore motion for patients with degenerative disc disease. Finite element modeling can be used to determine the biomechanics associated with nucleus replacement technologies. The current study focuses on a new nucleus replacement device designed as a conforming silicone implant with an internal void. A validated finite element model of the human lumbar L3-L4 motion segment was developed and used to investigate the influence of the nucleus replacement device on spine biomechanics. In addition, the effect of device design changes on biomechanics was determined. A 3D, L3-L4 finite element model was constructed from medical imaging data. Models were created with the normal intact nucleus, the nucleus replacement device, and a solid silicone implant. Probabilistic analysis was performed on the normal model to provide quantitative validation metrics. Sensitivity analysis was performed on the silicone Shore A durometer of the device. Models were loaded under axial compression followed by flexion/extension, lateral bending, or axial rotation. Compressive displacement, endplate stresses, reaction moment, and annulus stresses were determined and compared between the different models. The novel nucleus replacement device resulted in similar compressive displacement, endplate stress, and annulus stress and slightly higher reaction moment compared with the normal nucleus. The solid implant resulted in decreased displacement, increased endplate stress, decreased annulus stress, and decreased reaction moment compared with the novel device. With increasing silicone durometer, compressive displacement decreased, endplate stress increased, reaction moment increased, and annulus stress decreased. Finite element analysis was used to show that the novel nucleus replacement device results in similar biomechanics

Characters of infertility expression on autotetraploid rice with nucleus male sterility via N+ implantation

International Nuclear Information System (INIS)

Huang Qunce; Li Guoping; Li Yufeng

2006-01-01

The N + implantation experiment, taking autotetraploid rice with nucleus male sterility as materials, was finished. The off-spring colonies via N + implantation were selected, gaining some mutants in autotetraploid rice. The characters of infertility expression of the variant single plants, treated by the abnormal low temperature during male differentiation, were studied. As a result of 25 keV N + ion implantation with a low dose (1 x 10 17 cm - '2), there were some variant single plants in the autotetraploid rice. The variant single plants represented specially in infertility. Treated by the abnormal low temperature during male differentiation, some mutants showed obviously variant charactersin infertility following the morphological variation, but others preserved infertility of its parent. The segregation phenomena in the agronomic characters were visible in the lines of M 3 generation, but they kept the stable infertility. It is though that the characters of the infertility variation in the mutants may be allocated in the M 3 generation. (authors)

Near-nucleus optical observations of P/Halley

International Nuclear Information System (INIS)

Larson, S.M.

1987-01-01

The Near-Nucleus Studies Net of the International Halley Watch has obtained an extensive series of high resolution optical images of P/Halley during its most active phases in 1985-86 which may be useful in interpreting radio observations of Comet Halley. They often show coma structure resulting from anisotropic emission of dust and gas from the inhomogeneous nucleus. Images were obtained in broadband spectral regions to study dust coma morphology, and in medium to narrow spectral bands to isolate the principal emissions of CN, C 3 , C 2 , CO + and H 2 O + . The goals and methods of near-nucleus studies are discussed and recent studies of 1910 images are briefly reviewed. The role of dust jets and cometary activity in P/Halley is discussed and several examples of anisotropic emission of dust during the current apparition are shown. 12 references

What can an antiproton and a nucleus learn from each other

International Nuclear Information System (INIS)

Garreta, D.

1984-01-01

This chapter attempts to show that the - p-nucleus interaction may provide very useful information, both about the elementary - NN interaction and about nuclear structure. Topics covered include simple features which make a low-energy antiproton an interesting probe of the nucleus; simple features which make a nucleus an interesting target for an antiproton; antiproton-nucleus elastic scattering; antiproton-nucleus inelastic scattering; proton knock-out reactions on nuclei; and annihilation of the antiprotons in nuclei. The aim of experiment PS184 at the Low-Energy Antiproton Ring (LEAR) is to provide accurate data with regard to the - p-nucleus interaction in the following areas: the angular distribution of antiprotons elastically scattered from 12 C, 40 Ca, and 208 Pb; the excitation energy spectra and some angular distributions of antiprotons inelastically scattered from 12 C, 40 Ca, and 208 Pb; and the excitation energy spectra for proton knock-out reaction on 6 Li, 45 Sc, 123 Sb, and 209 B; at forward angles

NEUTRAL Na IN COMETARY TAILS AS A REMNANT OF EARLY AQUEOUS ALTERATION

Energy Technology Data Exchange (ETDEWEB)

Ellinger, Y.; Pauzat, F.; Doronin, M.; Zicler, E. [Laboratoire de Chimie Théorique, Sorbonne Universités, UPMC Univ. Paris 06, CNRS UMR 7616, F-75252 Paris CEDEX 05 (France); Mousis, O. [Laboratoire d’Astrophysique de Marseille (LAM), Aix Marseille Université, CNRS, UMR 7326, F-13388 Marseille (France); Guilbert-Lepoutre, A.; Ali-Dib, M. [Observatoire des Sciences de l’Univers de Besançon, Université de Franche-Comté, Institut UTINAM, CNRS/INSU, UMR 6213, F-35030 Besançon CEDEX (France); Leblanc, F. [LATMOS/IPSL, Sorbonne Universités, UPMC Univ. Paris 06, CNRS UMR 8190, F-75252 Paris CEDEX 05 (France); Doressoundiram, A. [LESIA—Observatoire de Paris, Sorbonne Universités, UPMC Univ. Paris 06, Univ. Paris-Diderot, CNRS UMR 8109, F-92190 Meudon (France)

2015-03-10

Observations of comet C/1995O1 Hale-Bopp during the spring of 1997 led to the discovery of a neutral sodium tail whose origin is still not clearly understood. Here, we propose an interpretation for the origin of this sodium tail, which is based upon chemical grounds. Starting from Na{sup +} trapped chemically during the condensation of refractory material in the protosolar nebula to its incorporation in the building blocks of comets and its transfer from refractory to volatile phases in the nucleus due to aqueous alteration, we follow the chemical path of sodium until its transformation into a neutral atom when released from the sublimating cometary ice. We propose that two Na reservoirs should coexist in a comet: one coming from the refractory dust, the other one from the icy matrix. Their relative importance would depend on the extent of the zone where liquid water formed within the nucleus and the time during which water remained liquid, thus favoring the Na{sup +} exchange between rocks and ice. These two key parameters would in turn strongly depend on the thermal history of the comet (amounts of radiogenic nuclides, orbital history, etc.). If our model is correct, the detection of Na originating from water ice would be a testimonial of the past aqueous alteration of the comet or its parent body.

Semi classical model of the neutron resonance compound nucleus

International Nuclear Information System (INIS)

Ohkubo, Makio

1995-01-01

A Semi-classical model of compound nucleus is developed, where time evolution and recurrence for many degrees of freedom (oscillators) excited simultaneously are explicitly considered. The effective number of oscillators plays the role in the compound nucleus, and the nuclear temperatures are derived, which are in good agreement with the traditional values. Time structures of the compound nucleus at resonance are considered, from which equidistant level series with an envelope of strength function of giant resonance nature is obtained. S-matrix formulation for fine structure resonance is derived. (author)

Differential metamorphosis alters the endocrine response in anuran larvae exposed to T3 and atrazine

International Nuclear Information System (INIS)

Freeman, Jennifer L.; Beccue, Nathan; Rayburn, A. Lane

2005-01-01

Pesticide chemical contamination is one of the suspected contributors of the amphibian population decline. The herbicide atrazine is one of the major surface water contaminants in the U.S. A previous study has shown that atrazine at concentrations as low as 100 parts per billion (ppb) increased the time to metamorphosis in Xenopus laevis tadpoles. However, questions remain as to the applicability of a study of a non-native species to a native organism. The possible effects of atrazine on developing Bufo americanus were explored. Atrazine at potentially (albeit high) environmental concentrations was found not to delay the metamorphosis of developing B. americanus tadpoles as observed in X. laevis. Several studies have indicated that atrazine affects thyroid hormones. Since thyroid hormones are critical in amphibian metamorphosis, B. americanus and X. laevis tadpoles were exposed to exogenous 3,5,3'-triiodothyronine (T 3 ). X. laevis were found to be more responsive to the effects of exogenous T 3 compared to B. americanus, indicating that X. laevis may be more sensitive to endocrine active chemicals than B. americanus. In X. laevis, nuclear heterogeneity has been associated with metamorphosis. Flow cytometric analysis of the nuclei of normal metamorphing B. americanus indicates a decrease in the amount of thyroid mediated chromatin alterations relative to the nuclei of metamorphing X. laevis. Indications are that the differential response to endocrine disruption is due to the differential role of chromatin associated gene expression during metamorphosis of B. americanus versus X. laevis. A second native species, Hyla versicolor, was observed to have the X. laevis nuclear pattern with respect to metamorphosis. As such, sensitivity to endocrine disruption is hypothesized not to be limited to laboratory non-native species

Polysialic acid enters the cell nucleus attached to a fragment of the neural cell adhesion molecule NCAM to regulate the circadian rhythm in mouse brain.

Science.gov (United States)

Westphal, Nina; Kleene, Ralf; Lutz, David; Theis, Thomas; Schachner, Melitta

2016-07-01

In the mammalian nervous system, the neural cell adhesion molecule NCAM is the major carrier of the glycan polymer polysialic acid (PSA) which confers important functions to NCAM's protein backbone. PSA attached to NCAM contributes not only to cell migration, neuritogenesis, synaptic plasticity, and behavior, but also to regulation of the circadian rhythm by yet unknown molecular mechanisms. Here, we show that a PSA-carrying transmembrane NCAM fragment enters the nucleus after stimulation of cultured neurons with surrogate NCAM ligands, a phenomenon that depends on the circadian rhythm. Enhanced nuclear import of the PSA-carrying NCAM fragment is associated with altered expression of clock-related genes, as shown by analysis of cultured neuronal cells deprived of PSA by specific enzymatic removal. In vivo, levels of nuclear PSA in different mouse brain regions depend on the circadian rhythm and clock-related gene expression in suprachiasmatic nucleus and cerebellum is affected by the presence of PSA-carrying NCAM in the cell nucleus. Our conceptually novel observations reveal that PSA attached to a transmembrane proteolytic NCAM fragment containing part of the extracellular domain enters the cell nucleus, where PSA-carrying NCAM contributes to the regulation of clock-related gene expression and of the circadian rhythm. Copyright © 2016 Elsevier Inc. All rights reserved.

The nucleus of differentiated root plant cells: modifications induced by arbuscular mycorrhizal fungi

Directory of Open Access Journals (Sweden)

G Lingua

2009-12-01

Full Text Available The nuclei of plant cells show marked differences in chromatin organisation, related to their DNA content, which ranges from the type with large strands of condensed chromatin (reticulate or chromonematic nuclei to one with mostly decondensed chromatin (chromocentric or diffuse nuclei. A loosening of the chromatin structure generally occurs in actively metabolising cells, such as differentiating and secretory cells, in relation to their high transcriptional activity. Endoreduplication may occur, especially in plants with a small genome, which increases the availability of nuclear templates, the synthesis of DNA, and probably regulates gene expression. Here we describe structural and quantitative changes of the chromatin and their relationship with transcription that occur in differentiated cells following an increase of their metabolism. The nuclei of root cortical cells of three plants with different 2C DNA content (Allium porrum, Pisum sativum and Lycopersicon esculentm and their modifications induced by arbuscular mycorrhization, which strongly increase the metabolic activity of colonised cells, are taken as examples.

Alteration of microRNA expression of human dental pulp cells during odontogenic differentiation.

Science.gov (United States)

Gong, Qimei; Wang, Runfu; Jiang, Hongwei; Lin, Zhengmei; Ling, Junqi

2012-10-01

MicroRNAs (miRNAs) play momentous roles in various biological processes including cell differentiation. However, little is known about the role of miRNAs in human dental pulp cells (hDPCs) during odontogenic differentiation. The aims of this study were to investigate the expression of miRNAs in the primary culture of hDPCs when incubated in odontogenic medium. The potential characteristics of hDPCs were investigated by miRNA microarray and real-time reverse transcriptase polymerase chain reaction. Bioinformatics (ie, target prediction, Gene Ontology analysis, and Kyoto Encyclopedia of Genes and Genomes mapping tools) were applied for predicting the complementary target genes of miRNAs and their biological functions. A total of 22 miRNAs were differentially expressed in which 12 miRNAs up-regulated and 10 miRNAs down-regulated in differentiated hDPCs compared with the control. The target genes of differential miRNAs were predicted to associate with several biological functions and signaling pathways including the mitogen-activated protein kinase (MAPK) and the Wnt signaling pathway. The differential expression miRNAs may be involved in governing hDPC odontogenic differentiation, thus contributing to the future investigations of regulatory mechanisms in reparative dentin formation and dental pulp regeneration. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

The Confined Hydrogen Atom with a Moving Nucleus

Science.gov (United States)

Fernandez, Francisco M.

2010-01-01

We study the hydrogen atom confined to a spherical box with impenetrable walls but, unlike earlier pedagogical articles on the subject, we assume that the nucleus also moves. We obtain the ground-state energy approximately by means of first-order perturbation theory and show that it is greater than that for the case in which the nucleus is clamped…

PREFACE: 11th International Conference on Nucleus-Nucleus Collisions (NN2012)

Science.gov (United States)

Li, Bao-An; Natowitz, Joseph B.

2013-03-01

The 11th International Conference on Nucleus-Nucleus Collisions (NN2012) was held from 27 May to 1 June 2012, in San Antonio, Texas, USA. It was jointly organized and hosted by The Cyclotron Institute at Texas A&M University, College Station and The Department of Physics and Astronomy at Texas A&M University-Commerce. Among the approximately 300 participants were a large number of graduate students and post-doctoral fellows. The Keynote Talk of the conference, 'The State of Affairs of Present and Future Nucleus-Nucleus Collision Science', was given by Dr Robert Tribble, University Distinguished Professor and Director of the TAMU Cyclotron Institute. During the conference a very well-received public lecture on neutrino astronomy, 'The ICEcube project', was given by Dr Francis Halzen, Hilldale and Gregory Breit Distinguished Professor at the University of Wisconsin, Madison. The Scientific program continued in the general spirit and intention of this conference series. As is typical of this conference a broad range of topics including fundamental areas of nuclear dynamics, structure, and applications were addressed in 42 plenary session talks, 150 parallel session talks, and 21 posters. The high quality of the work presented emphasized the vitality and relevance of the subject matter of this conference. Following the tradition, the NN2012 International Advisory Committee selected the host and site of the next conference in this series. The 12th International Conference on Nucleus-Nucleus Collisions (NN2015) will be held 21-26 June 2015 in Catania, Italy. It will be hosted by The INFN, Laboratori Nazionali del Sud, INFN, Catania and the Dipartimento di Fisica e Astronomia of the University of Catania. The NN2012 Proceedings contains the conference program and 165 articles organized into the following 10 sections 1. Heavy and Superheavy Elements 2. QCD and Hadron Physics 3. Relativistic Heavy-Ion Collisions 4. Nuclear Structure 5. Nuclear Energy and Applications of

The pion-nucleus interaction

International Nuclear Information System (INIS)

Afnan, I.R.

1977-04-01

The latest developments in the construction of pion-nucleus optical potential are presented and a comparison with the latest data on π+ 12 C is made. The suggested mechanisms for the (p,π) reaction are discussed with a comparison of the theoretical results with experiment. (Author)

Distinction between the extracellular matrix of the nucleus pulposus and hyaline cartilage: a requisite for tissue engineering of intervertebral disc

OpenAIRE

Mwale F.; Roughley P.; Antoniou J.

2004-01-01

Tissue engineering of intervertebral discs (IVD) using mesenchymal stem cells (MSCs) induced to differentiate into a disc-cell phenotype has been considered as an alternative treatment for disc degeneration. However, since there is no unique marker characteristic of discs and since hyaline cartilage and immature nucleus pulposus (NP) possess similar macromolecules in their extracellular matrix, it is currently difficult to recognize MSC conversion to a disc cell. This study was performed to c...

QMD and JAM calculations for high energy nucleon-nucleus collisions

International Nuclear Information System (INIS)

Niita, Koji

2002-01-01

We describe the two simulation codes, QMD and JAM (Jet AA Microscopic Transport Model), for high energy nuclear reactions. QMD can treat the nucleus-nucleus reactions as well as nucleon-nucleus reactions based on the molecular dynamics. We have applied the QMD code intensively to nucleon-nucleus reactions and checked its validity. The cross sections obtained by the QMD are now used for evaluation of high energy nuclear data in JAERI. JAM is a hadronic cascade code including the resonance and string model for the hadron-hadron collisions at high energy up to 200 GeV. We have developed a high energy particle transport code NMTC/JAM by including the JAM code for the intra-nuclear cascade part. (author)

Proton-Nucleus Collisions at the LHC: Scientific Opportunities and Requirements

CERN Document Server

Salgado, C A; Arleo, F; Armesto, N; Botje, M; Cacciari, M; Campbell, J; Carli, C; Cole, B; D'Enterria, D; Gelis, F; Guzey, V; Hencken, K; Jacobs, P; Jowett, J M; Klein, S R; Maltoni, F; Morsch, A; Piotrzkowski, K; Qiu, J W; Satogata, T; Sikler, F; Strikman, M; Takai, H; Vogt, R; Wessels, J P; White, S N; Wiedemann, U A; Wyslouch, B; Zhalov, M

2012-01-01

Proton-nucleus (p+A) collisions have long been recognized as a crucial component of the physics programme with nuclear beams at high energies, in particular for their reference role to interpret and understand nucleus-nucleus data as well as for their potential to elucidate the partonic structure of matter at low parton fractional momenta (small-x). Here, we summarize the main motivations that make a proton-nucleus run a decisive ingredient for a successful heavy-ion programme at the Large Hadron Collider (LHC) and we present unique scientific opportunities arising from these collisions. We also review the status of ongoing discussions about operation plans for the p+A mode at the LHC.

The mechanisms of the hadron-nucleus collision processes and of the hadron-nucleus collision induced nuclear reactions - in the light of experimental data

International Nuclear Information System (INIS)

Strugalski, Z.; Strugalska-Gola, E.

1997-01-01

The mechanisms of the hadron-nucleus collision processes and of the hadron-nucleus collision induced nuclear reactions are described - as experimentally based. The target nuclei are damaged definitely and locally in the collisions and the configurations of the nucleons in them became instable. The configuration must transit into stable stages of the nuclear transition reaction products. The difference between the initial internal energy of the unstable residual nucleus and the total final energy of the stable products of the nuclear transition reaction may be released in some cases

CILOSTAZOL INDUCES C-FOS EXPRESSION IN THE TRIGEMINAL NUCLEUS CAUDALIS AND BEHAVIOURAL CHANGES SUGGESTIVE OF HEADACHE WITH MIGRAINE-LIKE MANIFESTATIONS IN RATS

DEFF Research Database (Denmark)

Christensen, S. L. T.; Petersen, S.; Sorensen, D. B.

2016-01-01

in rats. Also, we tested the response to sumatriptan in order to evaluate the predictive properties of the model. Methods: The effect of cilostazol (125 mg/kg p.o.) was evaluated on a range of spontaneous behavioural parameters, light sensitivity and mechanical sensitivity thresholds. To assess headache...... specificity we evaluated the c-fos expression in the trigeminal nucleus caudalis. All experiments were done in female Sprague Dawley rats and the oestrous cycle was included in the analyses. Results: We found that cilostazol increased the light sensitivity and grooming behaviour of the rats and decreased......: The altered behaviours are suggestive of headache with migraine features, but not specific. The c-fos response in the trigeminal nucleus caudalis implies that the rats had pain originating from the head. The lack of response to sumatriptan disqualifies the model as predictive, but confirms the translation...

Study of the peculiarities of multiparticle production via event-by-event analysis in asymmetric nucleus-nucleus interactions

Science.gov (United States)

Fedosimova, Anastasiya; Gaitinov, Adigam; Grushevskaya, Ekaterina; Lebedev, Igor

2017-06-01

In this work the study on the peculiarities of multiparticle production in interactions of asymmetric nuclei to search for unusual features of such interactions, is performed. A research of long-range and short-range multiparticle correlations in the pseudorapidity distribution of secondary particles on the basis of analysis of individual interactions of nuclei of 197 Au at energy 10.7 AGeV with photoemulsion nuclei, is carried out. Events with long-range multiparticle correlations (LC), short-range multiparticle correlations (SC) and mixed type (MT) in pseudorapidity distribution of secondary particles, are selected by the Hurst method in accordance with Hurst curve behavior. These types have significantly different characteristics. At first, they have different fragmentation parameters. Events of LC type are processes of full destruction of the projectile nucleus, in which multicharge fragments are absent. In events of mixed type several multicharge fragments of projectile nucleus are discovered. Secondly, these two types have significantly different multiplicity distribution. The mean multiplicity of LC type events is significantly more than in mixed type events. On the basis of research of the dependence of multiplicity versus target-nuclei fragments number for events of various types it is revealed, that the most considerable multiparticle correlations are observed in interactions of the mixed type, which correspond to the central collisions of gold nuclei and nuclei of CNO-group, i.e. nuclei with strongly asymmetric volume, nuclear mass, charge, etc. Such events are characterised by full destruction of the target-nucleus and the disintegration of the projectile-nucleus on several multi-charged fragments.

Study of the peculiarities of multiparticle production via event-by-event analysis in asymmetric nucleus-nucleus interactions

Directory of Open Access Journals (Sweden)

Fedosimova Anastasiya

2017-01-01

Full Text Available In this work the study on the peculiarities of multiparticle production in interactions of asymmetric nuclei to search for unusual features of such interactions, is performed. A research of long-range and short-range multiparticle correlations in the pseudorapidity distribution of secondary particles on the basis of analysis of individual interactions of nuclei of 197 Au at energy 10.7 AGeV with photoemulsion nuclei, is carried out. Events with long-range multiparticle correlations (LC, short-range multiparticle correlations (SC and mixed type (MT in pseudorapidity distribution of secondary particles, are selected by the Hurst method in accordance with Hurst curve behavior. These types have significantly different characteristics. At first, they have different fragmentation parameters. Events of LC type are processes of full destruction of the projectile nucleus, in which multicharge fragments are absent. In events of mixed type several multicharge fragments of projectile nucleus are discovered. Secondly, these two types have significantly different multiplicity distribution. The mean multiplicity of LC type events is significantly more than in mixed type events. On the basis of research of the dependence of multiplicity versus target-nuclei fragments number for events of various types it is revealed, that the most considerable multiparticle correlations are observed in interactions of the mixed type, which correspond to the central collisions of gold nuclei and nuclei of CNO-group, i.e. nuclei with strongly asymmetric volume, nuclear mass, charge, etc. Such events are characterised by full destruction of the target-nucleus and the disintegration of the projectile-nucleus on several multi-charged fragments.

Polarization and alignment of nucleus fission fragments

International Nuclear Information System (INIS)

Barabanov, A.L.; Grechukhin, D.P.

1987-01-01

Correlation of fragment orientation with orientation axis of fissile nucleus and with n-vector f vector of fragment divergence is considered. Estimations of polarization and alignment of fission fragments of preliminarily oriented nuclei in correlation (with n-vector f recording) and integral (with n-vector f averaging) experiments were conducted. It is shown that high sensitivity of polarization and fragment alignment to the character of nucleus movement at the stage of descent from barrier to rupture point exists

The dynamic landscape of the cell nucleus.

Science.gov (United States)

Austin, Christopher M; Bellini, Michel

2010-01-01

While the cell nucleus was described for the first time almost two centuries ago, our modern view of the nuclear architecture is primarily based on studies from the last two decades. This surprising late start coincides with the development of new, powerful strategies to probe for the spatial organization of nuclear activities in both fixed and live cells. As a result, three major principles have emerged: first, the nucleus is not just a bag filled with nucleic acids and proteins. Rather, many distinct functional domains, including the chromosomes, resides within the confines of the nuclear envelope. Second, all these nuclear domains are highly dynamic, with molecules exchanging rapidly between them and the surrounding nucleoplasm. Finally, the motion of molecules within the nucleoplasm appears to be mostly driven by random diffusion. Here, the emerging roles of several subnuclear domains are discussed in the context of the dynamic functions of the cell nucleus.

Thalamic VPM nucleus in the behaving monkey. III. Effects of reversible inactivation by lidocaine on thermal and mechanical discrimination.

Science.gov (United States)

Duncan, G H; Bushnell, M C; Oliveras, J L; Bastrash, N; Tremblay, N

1993-11-01

1. The present study evaluates the necessity of the ventroposterior medial thalamic nucleus (VPM) for discrimination of the intensity of noxious heating, innocuous cooling, and innocuous tactile (airpuff) stimulation of the maxillary skin. 2. Two rhesus monkeys were trained to detect small differences (Lidocaine hydrochloride (2%) was microinjected into regions of thalamus where single-unit recordings had identified neuronal responses to the noxious heating and/or cooling stimuli. The effectiveness of the anesthetic blockade was monitored by multiunit recordings using microelectrodes positioned 1-3 mm from the orifice of the injection cannula. The monkey's ability to detect near-threshold changes in stimulus intensity was compared before and after each injection. 3. During six experimental sessions, single injections of 1-4 microliters lidocaine near the dorsomedial border of VPM did not significantly alter the monkey's ability to detect small changes in the intensity of noxious heat, cool, airpuff, or visual stimuli despite neurophysiological evidence that spontaneous neuronal activity was blocked within parts of VPM. 4. During three experiments, dual simultaneous microinjections of lidocaine (delivered through 2 microcannulae separated by approximately 1 mm) resulted in profound deficits in noxious heat discrimination, with lesser deficits in cool and airpuff discrimination; visual discrimination was never altered. Monitoring of adjacent microelectrodes revealed that although activity ventral to the injection sites was blocked, activity in medial thalamic nuclei, implicated in nociceptive processing, was probably not altered by these injections. 5. These data suggest that VPM is important for the perception of noxious and innocuous thermal stimuli as well as for the perception of tactile stimuli. However, considering the ineffectiveness of small single microinjections of lidocaine, it appears that some critical proportion of VPM must be inactivated to disrupt

Composite hydrogel of chitosan-poly(hydroxybutyrate-co-valerate) with chondroitin sulfate nanoparticles for nucleus pulposus tissue engineering.

Science.gov (United States)

Nair, Manitha B; Baranwal, Gaurav; Vijayan, Prajuna; Keyan, Kripa S; Jayakumar, R

2015-12-01

Intervertebral disc degeneration, occurring mainly in nucleus pulposus (NP), is a leading cause of low back pain. In seeking to mitigate this condition, investigators in the field of NP tissue engineering have increasingly studied the use of hydrogels. However, these hydrogels should possess appropriate mechanical strength and swelling pressure, and concurrently support the proliferation of chondrocyte-like cells. The objective of this study was to develop and validate a composite hydrogel for NP tissue engineering, made of chitosan-poly(hydroxybutyrate-co-valerate) (CP) with chondroitin sulfate (CS) nanoparticles, without using a cross linker. The water uptake ability, as well as the viscoelastic properties of this composite hydrogel, was similar to native tissue, as reflected in the complex shear modulus and stress relaxation values. The hydrogel could withstand varying stress corresponding to daily activities like lying down (0.01 MPa), sitting (0.5 MPa) and standing (1.0 MPa) under dynamic conditions. The hydrogels were stable in PBS for 2 weeks and its stiffness, elastic and viscous modulus did not alter significantly during this period. Both CP and CP-CS hydrogels could assist the viability and adhesion of adipose derived rat mesenchymal stem cells (ADMSCs). The viability and chondrogenic differentiation of MSCs was significantly enhanced in presence of CS nanoparticles. Thus, CS nanoparticles-incorporated chitosan-PHBV hydrogels offer great potential for NP tissue engineering. Copyright © 2015 Elsevier B.V. All rights reserved.

Differential effects of recombinant adeno-associated virus-mediated neuropeptide Y overexpression in the hypothalamic paraventricular nucleus and lateral hypothalamus on feeding behavior

NARCIS (Netherlands)

Tiesjema, Birgitte; Adan, Roger A. H.; Luijendijk, Mieneke C. M.; Kalsbeek, Andries; la Fleur, Susanne E.

2007-01-01

It is well known that neuropeptide Y (NPY) increases food intake. The hypothalamic paraventricular nucleus (PVN) and the lateral hypothalamus (LH) are both involved in the acute, hyperphagic effects of NPY. Although it is obvious that increased energy intake may lead to obesity, it is less

Silk fibroin porous scaffolds for nucleus pulposus tissue engineering

International Nuclear Information System (INIS)

Zeng, Chao; Yang, Qiang; Zhu, Meifeng; Du, Lilong; Zhang, Jiamin; Ma, Xinlong; Xu, Baoshan; Wang, Lianyong

2014-01-01

Intervertebral discs (IVDs) are structurally complex tissue that hold the vertebrae together and provide mobility to spine. The nucleus pulposus (NP) degeneration often results in degenerative IVD disease that is one of the most common causes of back and neck pain. Tissue engineered nucleus pulposus offers an alternative approach to regain the function of the degenerative IVD. The aim of this study is to determine the feasibility of porous silk fibroin (SF) scaffolds fabricated by paraffin-sphere-leaching methods with freeze-drying in the application of nucleus pulposus regeneration. The prepared scaffold possessed high porosity of 92.38 ± 5.12% and pore size of 165.00 ± 8.25 μm as well as high pore interconnectivity and appropriate mechanical properties. Rabbit NP cells were seeded and cultured on the SF scaffolds. Scanning electron microscopy, histology, biochemical assays and mechanical tests revealed that the porous scaffolds could provide an appropriate microstructure and environment to support adhesion, proliferation and infiltration of NP cells in vitro as well as the generation of extracellular matrix. The NP cell–scaffold construction could be preliminarily formed after subcutaneously implanted in a nude mice model. In conclusion, The SF porous scaffold offers a potential candidate for tissue engineered NP tissue. - Highlights: • Paraffin microsphere-leaching method is used to fabricate silk fibroin scaffold. • The scaffold has appropriate mechanical property, porosity and pore size • The scaffold supports growth and infiltration of nucleus pulposus cells. • Nucleus pulposus cells can secrete extracellular matrix in the scaffolds. • The scaffold is a potential candidate for tissue engineered nucleus pulposus

Silk fibroin porous scaffolds for nucleus pulposus tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Zeng, Chao; Yang, Qiang [Department of Spine Surgery, Tianjin Hospital, Tianjin 300211 (China); Tianjin Medical University, Tianjin 300070 (China); Zhu, Meifeng [The Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071 (China); Du, Lilong [Department of Spine Surgery, Tianjin Hospital, Tianjin 300211 (China); Tianjin Medical University, Tianjin 300070 (China); Zhang, Jiamin [The Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071 (China); Ma, Xinlong [Department of Spine Surgery, Tianjin Hospital, Tianjin 300211 (China); Xu, Baoshan, E-mail: xubaoshan99@126.com [Department of Spine Surgery, Tianjin Hospital, Tianjin 300211 (China); Wang, Lianyong, E-mail: wly@nankai.edu.cn [The Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071 (China)

2014-04-01

Intervertebral discs (IVDs) are structurally complex tissue that hold the vertebrae together and provide mobility to spine. The nucleus pulposus (NP) degeneration often results in degenerative IVD disease that is one of the most common causes of back and neck pain. Tissue engineered nucleus pulposus offers an alternative approach to regain the function of the degenerative IVD. The aim of this study is to determine the feasibility of porous silk fibroin (SF) scaffolds fabricated by paraffin-sphere-leaching methods with freeze-drying in the application of nucleus pulposus regeneration. The prepared scaffold possessed high porosity of 92.38 ± 5.12% and pore size of 165.00 ± 8.25 μm as well as high pore interconnectivity and appropriate mechanical properties. Rabbit NP cells were seeded and cultured on the SF scaffolds. Scanning electron microscopy, histology, biochemical assays and mechanical tests revealed that the porous scaffolds could provide an appropriate microstructure and environment to support adhesion, proliferation and infiltration of NP cells in vitro as well as the generation of extracellular matrix. The NP cell–scaffold construction could be preliminarily formed after subcutaneously implanted in a nude mice model. In conclusion, The SF porous scaffold offers a potential candidate for tissue engineered NP tissue. - Highlights: • Paraffin microsphere-leaching method is used to fabricate silk fibroin scaffold. • The scaffold has appropriate mechanical property, porosity and pore size • The scaffold supports growth and infiltration of nucleus pulposus cells. • Nucleus pulposus cells can secrete extracellular matrix in the scaffolds. • The scaffold is a potential candidate for tissue engineered nucleus pulposus.

Exact multiple scattering theory of two-nucleus collisions including the Pauli principle

International Nuclear Information System (INIS)

Gurvitz, S.A.

1981-01-01

Exact equations for two-nucleus scattering are derived in which the effects of the Pauli principle are fully included. Our method exploits a modified equation for the scattering of two identical nucleons, which is obtained at the beginning. Considering proton-nucleus scattering we found that the resulting amplitude has two components, one resembling a multiple scattering series for distinguishable particles, and the other a distorted (A-1) nucleon cluster exchange. For elastic pA scattering the multiple scattering amplitude is found in the form of an optical potential expansion. We show that the Kerman-McManus-Thaler theory of the optical potential could be easily modified to include the effects of antisymmetrization of the projectile with the target nucleons. Nucleus-nucleus scattering is studied first for distinguishable target and beam nucleus. Afterwards the Pauli principle is included, where only the case of deuteron-nucleus scattering is discussed in detail. The resulting amplitude has four components. Two of them correspond to modified multiple scattering expansions and the others are distorted (A-1)- and (A-2)- nucleon cluster exchange. The result for d-A scattering is extended to the general case of nucleus-nucleus scattering. The equations are simple to use and as such constitute an improvement over existing schemes

Theoretical interpretation of medium energy nucleon nucleus inelastic scattering

International Nuclear Information System (INIS)

Lagrange, Christian

1970-06-01

A theoretical study is made of the medium energy nucleon-nucleus inelastic scattering (direct interaction), by applying the distorted wave Born approximation such as can be deduced from the paired equation method. It is applied to the interpretation of the inelastic scattering of 12 MeV protons by 63 Cu; this leads us to make use of different sets of wave functions to describe the various states of the target nucleus. We analyze the nature of these states and the shape of the nucleon-nucleus interaction potential, and we compare the results with those obtained from other theoretical and experimental work. (author) [fr

J/$\\psi$ production in proton-nucleus and nucleus-nucleus interactions at the CERN SPS

CERN Document Server

Abreu, M C; Alexa, C; Arnaldi, R; Ataian, M R; Baglin, C; Baldit, A; Bedjidian, Marc; Beolè, S; Boldea, V; Bordalo, P; Borges, G; Bussière, A; Capelli, L; Castanier, C; Castor, J I; Chaurand, B; Chevrot, I; Cheynis, B; Chiavassa, E; Cicalò, C; Claudino, T; Comets, M P; Constans, N; Constantinescu, S; Cortese, P; De Falco, A; De Marco, N; Dellacasa, G; Devaux, A; Dita, S; Drapier, O; Ducroux, L; Espagnon, B; Fargeix, J; Force, P; Gallio, M; Gavrilov, Yu K; Gerschel, C; Giubellino, P; Golubeva, M B; Gonin, M; Grigorian, A A; Grossiord, J Y; Guber, F F; Guichard, A; Gulkanian, H R; Hakobyan, R S; Haroutunian, R; Idzik, M; Jouan, D; Karavitcheva, T L; Kluberg, L; Kurepin, A B; Le Bornec, Y; Lourenço, C; Macciotta, P; MacCormick, M; Marzari-Chiesa, A; Masera, M; Masoni, A; Monteno, M; Musso, A; Petiau, P; Piccotti, A; Pizzi, J R; Prado da Silva, W L; Prino, F; Puddu, G; Quintans, C; Ramello, L; Ramos, S; Rato-Mendes, P; Riccati, L; Romana, A; Santos, H; Saturnini, P; Scalas, E; Scomparin, E; Serci, S; Shahoyan, R; Sigaudo, F; Silva, S; Sitta, M; Sonderegger, P; Tarrago, X; Topilskaya, N S; Usai, G L; Vercellin, Ermanno; Villatte, L; Willis, N

2002-01-01

The NA38 and NA50 experiments at the CERN SPS have measured charmonium production in different colliding systems with the aim of observing a phase transition from ordinary hadronic matter towards a state in which quarks and gluons are deconfined (quark-gluon plasma, QGP). This experimental research is based on the prediction that the J/ psi yield should be suppressed in deconfined matter. The analysis of the data collected by the NA50 experiment with Pb-Pb collisions at 158 GeV/c per nucleon shows that the J/ psi is anomalously suppressed with respect to the pattern observed in proton-nucleus and light ion reactions. (9 refs).

What can an antiproton and a nucleus learn from each other

International Nuclear Information System (INIS)

Garreta, D.

1982-05-01

Simple features which make a low-energy antiproton an interesting probe of the nucleus, and a nucleus an interesting target for an antiproton are presented. Then antiproton-nucleus inelastic and elastic scattering, proton knock-out reactions on nuclei, annihilation of the antiproton in nuclei are reviewed. The aims of the experiment PS184 at LEAR are given

Numerical Simulation of the Kinetic Critical Nucleus

OpenAIRE

Sanada, Masaaki; Nishioka, Kazumi; Okada, Masahumi; Maksimov, Igor, L.

1997-01-01

Our main interest is to see whether the number density indicates a peak at the kinetically stable critical nucleus due to its kinetical stability. We have numerically calculated the time evolution of the number densities of clusters in the case of water vapor nucleation. We employ the condition in which the difference between the size of the thermodynamic crtitical nucleus and that of the kinetic one is appreciable. The results show that the peak does not appear in the number densities of clu...

Msx2 alters the timing of retinal ganglion cells fate commitment and differentiation

Energy Technology Data Exchange (ETDEWEB)

Jiang, Shao-Yun, E-mail: jiangshaoyun@yahoo.com [School of Dentistry, Tianjin Medical University, 12 Qi Xiang Tai Street, Tianjin 300070 (China); Wang, Jian-Tao, E-mail: wangjiantao65@hotmail.com [Eye Center, Tianjin Medical University, 64 Tongan Road, Tianjin 300070 (China); Dohney Eye Institute, Keck School of Medicine, University of Southern California, 1355 San Pablo Street, DOH 314, Los Angeles, CA 90033 (United States)

2010-05-14

Timing of cell fate commitment determines distinct retinal cell types, which is believed to be controlled by a tightly coordinated regulatory program of proliferation, cell cycle exit and differentiation. Although homeobox protein Msx2 could induce apoptosis of optic vesicle, it is unclear whether Msx2 regulates differentiation and cell fate commitment of retinal progenitor cells (RPCs) to retinal ganglion cells (RGCs). In this study, we show that overexpression of Msx2 transiently suppressed the expression of Cyclin D1 and blocked cell proliferation. Meanwhile, overexpression of Msx2 delayed the expression of RGC-specific differentiation markers (Math5 and Brn3b), which showed that Msx2 could affect the timing of RGCs fate commitment and differentiation by delaying the timing of cell cycle exit of retinal progenitors. These results indicate Msx2 possesses dual regulatory functions in controlling cell cycle progression of retinal RPCs and timing of RGCs differentiation.

MR imaging of transient synovitis: differentiation from septic arthritis

International Nuclear Information System (INIS)

Yang, W.J.; Im, S.A.; Lim, G.Y.; Chun, H.J.; Jung, N.Y.; Sung, M.S.; Choi, B.G.

2006-01-01

Transient synovitis is the most common cause of acute hip pain in children. However, MR imaging findings in transient synovitis and the role of MR imaging in differentiating transient synovitis from septic arthritis have not been fully reported. To describe the MR findings of transient synovitis and to determine whether the MR characteristics can differentiate this disease entity from septic arthritis. Clinical findings and MR images of 49 patients with transient synovitis (male/female 36/13, mean age 6.1 years) and 18 patients with septic arthritis (male/female 10/8, mean age 4.9 years) were retrospectively reviewed. MR findings of transient synovitis were symptomatic joint effusion, synovial enhancement, contralateral joint effusion, synovial thickening, and signal intensity (SI) alterations and enhancement in surrounding soft tissue. Among these, SI alterations and enhancement in bone marrow and soft tissue, contralateral joint effusion, and synovial thickening were statistically significant MR findings in differentiating transient synovitis from septic arthritis. The statistically significant MR findings in transient synovitis are contralateral (asymptomatic) joint effusions and the absence of SI abnormalities of the bone marrow. It is less common to have SI alterations and contrast enhancement of the soft tissues. The statistically significant MR findings in septic arthritis are SI alterations of the bone marrow, and SI alterations and contrast enhancement of the soft tissue. Ipsilateral effusion and synovial thickening and enhancement are present in both diseases

Ultra-differentiation of Sperm Tail of Lesser Egyptian Jerboa, Jaculus jaculus (Family: Dipodidae

Directory of Open Access Journals (Sweden)

Osama M. Sarhan

2016-01-01

Full Text Available In the present study, events of sperm tail differentiation in Lesser Egyptian Jerboa, Jaculus jaculus were studied for the first time. Generally, stages of sperm tail differentiation are more or less similar to that described by other studies in other rodents. In the present species, special structures were observed. These structures include, first: the formation of a hollow large unit of microtubules that appears to surround the nuclear envelope at its equatorial plane. The manchette microtubules (MMs are re-oriented toward the longitudinal direction and attached along hollow large unit of microtubules. Second, the formation of perinuclear space filled with an electron-translucent substance surrounds the posterior third of the developing nucleus. Third, the nuclear fossa and the connecting piece were inserted in the ventrodorsal region of the nucleus. Fourth, the fibrous sheath (FS is formed of dextral spiral fibrous ribs. Finally, the sperm tail of the present species has a single outer FS, however, other rodents, having additional inner fibrous units, between the outer FS and the inner developing axoneme.

Kaon-nucleus reactions and hypernuclei

International Nuclear Information System (INIS)

Dover, C.B.

1987-01-01

Recent advances in hypernuclear physics and kaon-nucleus scattering are discussed, with emphasis on the spectroscopy of Λ single particle states in heavy systems, as revealed by the (π + ,K + ) reaction. 26 refs., 8 figs

A study of the nucleus-nucleus total reaction cross section of stable systems at intermediate energies: An application to 12C

Science.gov (United States)

Hu, Liyuan; Song, Yushou; Hou, Yingwei; Liu, Huilan; Li, Hui

2018-07-01

A semi-microscopic analytical expression of the nucleus-nucleus total reaction cross section (σR) was proposed based on the strong absorption model. It is suitable for stable nuclei at intermediate energies. The matter density distributions of nuclei and the nucleon-nucleon total cross section were both considered. Particularly, the Fermi motion effect of the nucleons in a nucleus was also taken into account. The parametrization of σR was applied to the colliding systems including 12C. The experimental data at energies from 30 to 1000 MeV/nucleon were well reproduced, according to which an approach of deriving σR without adjustable parameters was developed. The necessity of considering the Fermi motion effect in the parametrization was discussed.

Neuronal plasticity in the hedgehog supraoptic nucleus during hibernation.

Science.gov (United States)

Sanchez-Toscano, F; Caminero, A A; Machin, C; Abella, G

1989-01-01

The purpose of the present study was to identify processes of plasticity in the receptive field of neurosecretory neurons of the supraoptic nucleus during hibernation in the hedgehog, in order to correlate them with the increased neurosecretory activity observed in this nucleus during this annual period. Using the Rapid Golgi method, a quantitative study was conducted in the receptive field of bipolar and multipolar neurons (the main components of the nucleus). Results indicate a generalized increase in the following characteristics: (1) number of dendritic spines per millimeter along the dendritic shafts; (2) degree of branching in the dendritic field; and (3) dendritic density around the neuronal soma. These data demonstrate modification of the dendritic field in the supraoptic nucleus during hibernation, a change undoubtedly related to functional conditions. Since the observed changes affect structures such as dendritic spines which are directly related to the arrival of neural afferences, the discussion is centered on the types of stimuli which may be responsible for the observed processes.

Involvement of the oxytocin system in the nucleus accumbens in the regulation of juvenile social novelty-seeking behavior.

Science.gov (United States)

Smith, Caroline J W; Mogavero, Jazmin N; Tulimieri, Maxwell T; Veenema, Alexa H

2017-07-01

Exploration of novel environments, stimuli, and conspecifics is highly adaptive during the juvenile period, as individuals transition from immaturity to adulthood. We recently showed that juvenile rats prefer to interact with a novel individual over a familiar cage mate. However, the neural mechanisms underlying this juvenile social novelty-seeking behavior remain largely unknown. One potential candidate is the oxytocin (OXT) system, given its involvement in various motivated social behaviors. Here, we show that administration of the specific oxytocin receptor antagonist desGly-NH 2 ,d(CH 2 ) 5 -[Tyr(Me) 2 ,Thr 4 ]OVT reduces social novelty seeking-behavior in juvenile male rats when injected into the nucleus accumbens (10ng/0.5μl/side). The same drug dose was ineffective at altering social novelty-seeking behavior when administered into the lateral septum or basolateral amygdala. These results are the first to suggest the involvement of the OXT system in the nucleus accumbens in the regulation of juvenile social novelty-seeking behavior. Copyright © 2017 Elsevier Inc. All rights reserved.

Preservation of the nucleus X-pelvic floor motosystem in amyotrophic lateral sclerosis

DEFF Research Database (Denmark)

Schrøder, H D; Reske-Nielsen, E

1984-01-01

to the neuropathological findings, and the observations are compared with previous neuropathological studies concerning Onuf's nucleus X as well with experimental studies including this nucleus. It is pointed out that structural and biochemical differences must exist between nucleus X neurons and other motoneurons....

GR and ER co-activation alters the expression of differentiation genes and associates with improved ER+ breast cancer outcome

Science.gov (United States)

West, Diana C.; Pan, Deng; Tonsing-Carter, Eva Y.; Hernandez, Kyle M.; Pierce, Charles F.; Styke, Sarah C.; Bowie, Kathleen R.; Garcia, Tzintzuni I.; Kocherginsky, Masha; Conzen, Suzanne D.

2016-01-01

In estrogen receptor (ER)-negative breast cancer (BC), high tumor glucocorticoid receptor (GR) expression has been associated with a relatively poor outcome. In contrast, using a meta-analysis of several genomic datasets, here we find that tumor GR mRNA expression is associated with improved ER+ relapse-free survival (RFS) (independently of progesterone receptor (PR) expression). To understand the mechanism by which GR expression is associated with a better ER+ BC outcome, the global effect of GR-mediated transcriptional activation in ER+ BC cells was studied. Analysis of GR chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) in ER+/GR+ MCF-7 cells revealed that upon co-activation of GR and ER, GR chromatin association became enriched at proximal promoter regions. Furthermore, following ER activation, increased GR chromatin association was observed at ER, FOXO, and AP1 response elements. In addition, ER associated with GR response elements, suggesting that ER and GR interact in a complex. Co-activation of GR and ER resulted in increased expression (relative to ER activation alone) of transcripts that encode proteins promoting cellular differentiation (e.g. KDM4B, VDR) and inhibiting the Wnt-signaling pathway (IGFBP4). Finally, expression of these individual pro-differentiation genes was associated with significantly improved RFS in ER+ BC patients. Together, these data suggest that the co-expression and subsequent activity of tumor cell GR and ER contribute to the less aggressive natural history of early-stage BC by coordinating the altered expression of genes favoring differentiation. Implications The interaction between estrogen and glucocorticoid receptor activity highlights the importance of context-dependent nuclear receptor function in cancer. PMID:27141101

Pion-nucleus cross sections approximation

International Nuclear Information System (INIS)

Barashenkov, V.S.; Polanski, A.; Sosnin, A.N.

1990-01-01

Analytical approximation of pion-nucleus elastic and inelastic interaction cross-section is suggested, with could be applied in the energy range exceeding several dozens of MeV for nuclei heavier than beryllium. 3 refs.; 4 tabs

Medium energy nucleon-nucleus scattering theory by semi-classical distorted wave approximation

Energy Technology Data Exchange (ETDEWEB)

Ogata, Kazuyuki [Kyushu Univ., Fukuoka (Japan)

1998-07-01

The semiclassical distorted wave model (SCDW) is one of the quantum mechanical models for nucleon inelastic and charge exchange scattering at intermediate energies. SCDW can reproduce the double differential inclusive cross sections for multi-step direct processes quite well in the angular and outgoing energy regions where the model is expected to work. But the model hitherto assumed on-the-energy-shell (on-shell) nucleon-nucleon scattering in the nucleus, neglecting the difference in the distorting potentials for the incoming and the outgoing particles and also the Q-value in the case of (p,n) reactions. There had also been a problem in the treatment of the exchange of colliding nucleons. Now we modify the model to overcome those problems and put SCDW on sounder theoretical foundations. The modification results in slight reduction (increase) of double differential cross sections at forward (backward) angles. We also examine the effect of the in-medium modification of N-N cross sections in SCDW and find it small. A remedy of the disagreement at very small and large angles in terms of the Wigner transform of the single particle density matrix is also discussed. This improvement gives very promising results. (author)

Recent Developments in Neutrino/Antineutrino-Nucleus Interactions

Directory of Open Access Journals (Sweden)

Jorge G. Morfín

2012-01-01

Full Text Available Recent experimental results and developments in the theoretical treatment of neutrino-nucleus interactions in the energy range of 1–10 GeV are discussed. Difficulties in extracting neutrino-nucleon cross sections from neutrino-nucleus scattering data are explained and significance of understanding nuclear effects for neutrino oscillation experiments is stressed. Detailed discussions of the status of two-body current contribution in the kinematic region dominated by quasielastic scattering and specific features of partonic nuclear effects in weak DIS scattering are presented.

Differential behavioral profile induced by the injection of dipotassium chlorazepate within brain areas that project to the nucleus accumbens septi.

OpenAIRE

Llano López, Luis H.; Caif, Fernando; Fraile, Miriam; Tinnirello, Belén; Landa-Gargiulo, Adriana I.; Lafuente, José V.; Baiardi, Gustavo Carlos; Gargiulo, Pascual Angel

2015-01-01

The effect of the agonism on g-aminobutyric acid (GABA) receptors was studied within medial prefrontal cortex (mPFC), amygdala (AMY) and ventral hipocampus (VH) in the plus-maze test in male rats bilaterally cannulated. These structures send glutamatergic projections to the nucleus accumbens septi (NAS), in which interaction and integration between these afferent pathways has been described. In a previous study of our group, blockade of glutamatergic transmission within NAS induced an anxioly...

Method of a fast selection of inelastic nucleus-nucleus collisions for the CMS experiment

International Nuclear Information System (INIS)

Krasnov, V.A.; Malakhov, A.I.; Savina, M.V.; Shmatov, S.V.; Zarubin, P.I.

1998-01-01

On the basis of the HIJING generator simulation of heavy ion collisions at ultrarelativistic energy scale, a method of a fast selection of inelastic nucleus-nucleus interactions is proposed for the CMS experiment at LHC. The basic idea is to use the time coincidence of signals with resolution better than 1 ns from the two very forward calorimeter arms covering the acceptance 3<|η|<5. The method efficiency is investigated by variation of energy thresholds in the calorimeters for different colliding ion species, namely, PbPb, NbNb, CaCa, OO, pPb, pCa, pp. It is shown that a stable efficiency of event selection (∼98%) is provided in an energy threshold range up to 100 GeV for nuclear collisions at 5 TeV/nucleon in the centre of mass system. In the pp collision case the relevant efficiency drops from 93% down to 80%

Analysis of a deep nucleus of Tehuantepec Gulf

International Nuclear Information System (INIS)

Ordonez R, E.; Lopez M, J.; Ramirez T, J. J.; Machain C, M. L.

2009-10-01

A nucleus of sediments obtained in the deep of Tehuantepec Gulf is analyzed; this nucleus has the particularity of to be a sampling of longitude of 18.3 m that include the total of last period glacial, few times obtained in our country. The physical chemistry composition of 10 selected fractions are analyzed with the purpose of to understand the formation processes of deep ocean along the period of 120 000 years, that includes the extracted fraction. Crystallography analysis, morphology, physical chemistry characterization and activity gamma were made. Finding that the content of organic matter falls as the superficial area increases, also was found the presence of natural uranium in similar concentration and balance with its radiogenic descendants along the nucleus profile what suggests the uranium migration to interior of mineral grains. (Author)

Labeling of neuronal differentiation and neuron cells with biocompatible fluorescent nanodiamonds.

Science.gov (United States)

Hsu, Tzu-Chia; Liu, Kuang-Kai; Chang, Huan-Cheng; Hwang, Eric; Chao, Jui-I

2014-05-16

Nanodiamond is a promising carbon nanomaterial developed for biomedical applications. Here, we show fluorescent nanodiamond (FND) with the biocompatible properties that can be used for the labeling and tracking of neuronal differentiation and neuron cells derived from embryonal carcinoma stem (ECS) cells. The fluorescence intensities of FNDs were increased by treatment with FNDs in both the mouse P19 and human NT2/D1 ECS cells. FNDs were taken into ECS cells; however, FNDs did not alter the cellular morphology and growth ability. Moreover, FNDs did not change the protein expression of stem cell marker SSEA-1 of ECS cells. The neuronal differentiation of ECS cells could be induced by retinoic acid (RA). Interestingly, FNDs did not affect on the morphological alteration, cytotoxicity and apoptosis during the neuronal differentiation. Besides, FNDs did not alter the cell viability and the expression of neuron-specific marker β-III-tubulin in these differentiated neuron cells. The existence of FNDs in the neuron cells can be identified by confocal microscopy and flow cytometry. Together, FND is a biocompatible and readily detectable nanomaterial for the labeling and tracking of neuronal differentiation process and neuron cells from stem cells.

Social and physical environment alter cocaine conditioned place preference and dopaminergic markers in adolescent male rats.

Science.gov (United States)

Zakharova, E; Miller, J; Unterwald, E; Wade, D; Izenwasser, S

2009-10-20

This study was done to determine whether social and environmental factors alter cocaine reward and proteins implicated in mediating drug reward in rats during early adolescence. On postnatal day (PND) 23, rats were housed under conditions where both social (number of rats per cage) and environmental (availability of toys) factors were manipulated. Socially isolated rats were housed alone impoverished with no toys (II) or enriched with toys (IE). Social rats were housed two rats/cage with no toys (SI2) or with toys (SE2), or three/cage with (SE3) or without (SI3) toys. On PND 43, cocaine conditioned place preference (CPP) sessions began with the post-test done on PND 47. Cocaine CPP was established in response to 5 or 10 mg/kg cocaine in II rats, and CPP was decreased with the addition of cage mates or toys. No CPP was seen to any dose in SI3 or SE3 rats. Enriched housing (SE3) increased dopamine transporter (DAT) protein in the nucleus accumbens compared to II. There also were differential effects of cocaine on tyrosine hydroxylase and DAT depending on housing, with both increased by cocaine in II but not SE3 rats. DARPP-32 was unchanged by housing or cocaine, while phospho-Thr(34)-DARPP-32 was increased by cocaine treatment across conditions. Thus, both social and environmental enrichment decrease cocaine CPP during adolescence and different housing alters proteins that regulate dopaminergic neurotransmission in a manner that may account for the observed differences in cocaine-induced reward.

Angular distributions of nucleons emitted in high energy hadron-nucleus collisions

International Nuclear Information System (INIS)

Strugalski, Z.

1983-01-01

Angular distributions of ''fast'' protons, of kinetic energy from about 20 to about 400 MeV, emitted in pion-xenon nucleus collisions at 3.5 GeV/c momentum were studied in two groups of events - when particles are produced and when particle production does not occur. The distributions are practically the same in both the groups of events and in subgroups of events with various multiplicities of emitted protons. Comparison of angular distributions of protons emitted in pion-xenon nucleus collisions at 3.5 GeV/c momentum with corresponding angular distributions of protons emitted in proton-emulsion collisions at 300-400 GeV/c momentum is performed. Results obtained allow to conclude that average value of the nucleon emission angle and the nucleon angular distributions do not depend practically on the nuclear matter layer thickness the incident hadron collided with. Fast nucleons emitted from the target nucleus seem did not interact inside the parent nucleus. Fast nucleon angular distributions do not depend on the energy of incident hadron, they are the same for pion-nucleus and for proton-nucleus collisions as well

The Mathematical Model High Energy Collisions Process Hadron-Nucleus

International Nuclear Information System (INIS)

Wojciechowski, A.; Strugalska-Gola, E.; Strugalski, Z.

2002-01-01

During the passage high energy hadron by the heavy nucleus emitted are nucleons and many other particles from which most more group are nucleons and mesons π + π - π 0 . in this work we will present the mathematical model which is a simplified description of basic processes in the interior of the nucleus during passing of the hadron by the nucleus. Result of calculations we will compare with experimental results. Experimental data are based on photographs of 180 litre xenon bubble chambers (180 1 KKP) of Institute of Theoretical and Experimental Physics in Moscow (ITEF, Moscow) irradiated with the beam of mesons π - with momentum 3.5 GeV/c. (author)

What is a cometary nucleus

International Nuclear Information System (INIS)

Lyttleton, R.A.

1977-01-01

Descriptions of actual observed comets associate a range of ill-defined meanings with the term nucleus. In recent years use of the word has been even further extended (or contracted) to mean a postulated solid core constituting the permanent element of a comet and necessarily of size far below resolution and measurability. It is maintained by the postulants that this core, acted upon by solar radiation and the solar wind, is the fount and origin of practically the whole great variety of observed cometary physical phenomena. In order that this micro-nucleus shall 'explain' observed properties, it is endowed with a large number of entirely ad-hoc qualities specially devised to produce the very effects it is wished to explain, but the processes so proffered rely almost entirely on purely verbal asseverations that they will work in the way required. No source or mechanism of origin for the imaginary micro-nucleus, of which there would need to be myriads, is in sight, nor can the assumption explain the dynamical properties of long-period comets and their association with the galactic plane and the solar apex. The postulate is in any event ruled out by Occam's principle as having no basis in fact or theory and is not required to explain the observed properties of comets. The large number of additional special assumptions introduced mean that the structure as a whole does not constitute a proper scientific theory. (author)

Ketamine differentially restores diverse alterations of neuroligins in brain regions in a rat model of neuropathic pain-induced depression.

Science.gov (United States)

Pan, Wei; Zhang, Guang-Fen; Li, Hui-Hui; Ji, Mu-Huo; Zhou, Zhi-Qiang; Li, Kuan-Yu; Yang, Jian-Jun

2018-07-04

Depression is present in a large proportion of patients suffering from chronic pain, and yet the underlying mechanisms remain to be elucidated. Neuroligins (NLs), as a family of cell-adhesion proteins, are involved in synaptic formation and have been linked to various neuropsychiatric disorders. Here, we studied the alterations in NL1 and NL2 in the medial prefrontal cortex (mPFC), the anterior cingulate cortex (ACC), and the hippocampus in a rat model of neuropathic pain-induced depression, and whether ketamine, a rapid and robust antidepressant, could restore these abnormalities. In the present study, we found that spared nerve injury induced significant mechanical allodynia and subsequent depressive-like symptoms, along with decreased NL1 and increased NL2 in the mPFC, decreased NL1 in the ACC, and decreased NL2 in the hippocampus. In addition, brain-derived neurotrophic factor (BDNF) was reduced in these brain regions. It is noteworthy that ketamine (10 mg/kg) relieved neuropathic pain-induced depressive behaviors and restored alterations of BDNF and NLs in the mPFC and the hippocampus at 24 h and 72 h after the administration of ketamine, but only restored BDNF in the ACC. In conclusion, NLs showed diverse changes in different brain regions in the rat model of neuropathic pain-induced depression, which could be reversed differentially by the administration of ketamine.

Homer2 deletion alters dendritic spine morphology but not alcohol-associated adaptations in GluN2B-containing NMDA receptors in the nucleus accumbens

Directory of Open Access Journals (Sweden)

Natalie S McGuier

2015-02-01

Full Text Available Repeated exposure to ethanol followed by withdrawal leads to the alterations in glutamatergic signaling and impaired synaptic plasticity in the nucleus accumbens (NAc in both clinical and preclinical models of ethanol exposure. Homer2 is a member of a family of postsynaptic density (PSD scaffolding proteins that functions in part to cluster NMDA signaling complexes in the PSD, and has been shown to be critically important for plasticity in multiple models of drug and alcohol abuse. Here we used Homer2 KO mice and a chronic intermittent intraperitoneal (IP ethanol injection model to investigate a potential role for the protein in ethanol-induced adaptations in dendritic spine morphology and PSD protein expression. While deletion of Homer2 was associated with increased density of long spines on medium spiny neurons of the NAc core of saline treated mice, ethanol exposure had no effect on dendritic spine morphology in either wild-type (WT or Homer2 KO mice. Western blot analysis of tissue samples from the NAc enriched for PSD proteins revealed a main effect of ethanol treatment on the expression of GluN2B, but there was no effect of genotype or treatment on the expression other glutamate receptor subunits or PSD95. These data indicate that the global deletion of Homer2 leads to aberrant regulation of dendritic spine morphology in the NAc core that is associated with an increased density of long, thin spines. Unexpectedly, intermittent IP ethanol did not affect spine morphology in either WT or KO mice. Together these data implicate Homer2 in the formation of long, thin spines and further supports its role in neuronal structure.

Selective alterations in cerebral metabolism within the mesocorticolimbic dopaminergic system produced by acute cocaine administration in rats

Energy Technology Data Exchange (ETDEWEB)

Porrino, L.J.; Domer, F.R.; Crane, A.M.; Sokoloff, L.

1988-05-01

The 2-(/sup 14/C)deoxyglucose method was used to examine the effects of acute intravenous administration of cocaine on local cerebral glucose utilization in rats. These effects were correlated with the effects of cocaine on locomotor activity assessed simultaneously in the same animals. At the lowest dose of cocaine, 0.5 mg/kg (1.47 mumol/kg), alterations in glucose utilization were restricted to the medial prefrontal cortex and nucleus accumbens. Metabolic activity at 1.0 mg/kg (2.9 mumol/kg) was altered in these structures, but in the substantia nigra reticulata and lateral habenula as well. The selectivity of cocaine's effects at low doses demonstrates the particular sensitivity of these structures to cocaine's actions in the brain. In contrast, 5.0 mg/kg (14.7 mumol/kg) produced widespread changes in glucose utilization, particularly in the extrapyramidal system. Only this dose significantly increased locomotor activity above levels in vehicle-treated controls. Rates of glucose utilization were positively correlated with locomotor activity in the globus pallidus, substantia nigra reticulata, and subthalamic nucleus, and negatively correlated in the lateral habenula.

The Verticillium-specific protein VdSCP7 localizes to the plant nucleus and modulates immunity to fungal infections.

Science.gov (United States)

Zhang, Lisha; Ni, Hao; Du, Xuan; Wang, Sheng; Ma, Xiao-Wei; Nürnberger, Thorsten; Guo, Hui-Shan; Hua, Chenlei

2017-07-01

Fungal pathogens secrete effector proteins to suppress plant basal defense for successful colonization. Resistant plants, however, can recognize effectors by cognate R proteins to induce effector-triggered immunity (ETI). By analyzing secretomes of the vascular fungal pathogen Verticillium dahliae, we identified a novel secreted protein VdSCP7 that targets the plant nucleus. The green fluorescent protein (GFP)-tagged VdSCP7 gene with either a mutated nuclear localization signal motif or with additional nuclear export signal was transiently expressed in Nicotiana benthamiana, and investigated for induction of plant immunity. The role of VdSCP7 in V. dahliae pathogenicity was characterized by gene knockout and complementation, and GFP labeling. Expression of the VdSCP7 gene in N. benthamiana activated both salicylic acid and jasmonate signaling, and altered the plant's susceptibility to the pathogens Botrytis cinerea and Phytophthora capsici. The immune response activated by VdSCP7 was highly dependent on its initial extracellular secretion and subsequent nuclear localization in plants. Knockout of the VdSCP7 gene significantly enhanced V. dahliae aggressiveness on cotton. GFP-labeled VdSCP7 is secreted by V. dahliae and accumulates in the plant nucleus. We conclude that VdSCP7 is a novel effector protein that targets the host nucleus to modulate plant immunity, and suggest that plants can recognize VdSCP7 to activate ETI during fungal infection. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Glucose sensing by GABAergic neurons in the mouse nucleus tractus solitarii

Science.gov (United States)

Boychuk, Carie R.; Gyarmati, Peter; Xu, Hong

2015-01-01

Changes in blood glucose concentration alter autonomic function in a manner consistent with altered neural activity in brain regions controlling digestive processes, including neurons in the brain stem nucleus tractus solitarii (NTS), which process viscerosensory information. With whole cell or on-cell patch-clamp recordings, responses to elevating glucose concentration from 2.5 to 15 mM were assessed in identified GABAergic NTS neurons in slices from transgenic mice that express EGFP in a subset of GABA neurons. Single-cell real-time RT-PCR was also performed to detect glutamic acid decarboxylase (GAD67) in recorded neurons. In most identified GABA neurons (73%), elevating glucose concentration from 2.5 to 15 mM resulted in either increased (40%) or decreased (33%) neuronal excitability, reflected by altered membrane potential and/or action potential firing. Effects on membrane potential were maintained when action potentials or fast synaptic inputs were blocked, suggesting direct glucose sensing by GABA neurons. Glucose-inhibited GABA neurons were found predominantly in the lateral NTS, whereas glucose-excited cells were mainly in the medial NTS, suggesting regional segregation of responses. Responses were prevented in the presence of glucosamine, a glucokinase (GCK) inhibitor. Depolarizing responses were prevented when KATP channel activity was blocked with tolbutamide. Whereas effects on synaptic input to identified GABAergic neurons were variable in GABA neurons, elevating glucose increased glutamate release subsequent to stimulation of tractus solitarius in unlabeled, unidentified neurons. These results indicate that GABAergic NTS neurons act as GCK-dependent glucose sensors in the vagal complex, providing a means of modulating central autonomic signals when glucose is elevated. PMID:26084907

Fluctuations and correlations in nucleus-nucleus collisions within transport approaches

International Nuclear Information System (INIS)

Konchakovski, Volodymyr P.

2009-01-01

The current thesis is devoted to a systematic study of fluctuations and correlations in heavy-ion collisions, which might be considered as probes for the phase transition and the critical point in the phase diagram, within the Hadron-String- Dynamics (HSD) microscopic transport approach. This is a powerful tool to study nucleus-nucleus collisions and allows to completely simulate experimental collisions on an event-by-event basis. Thus, the transport model has been used to study fluctuations and correlations including the influence of experimental acceptance as well as centrality, system size and collision energy. The comparison to experimental data can separate the effects induced by a phase transition since there is no phase transition in the HSD version used here. Firstly the centrality dependence of multiplicity fluctuations has been studied. Different centrality selections have been performed in the analysis in correspondence to the experimental situation. For the fixed target experiment NA49 events with fixed numbers of the projectile participants have been studied while in the collider experiment PHENIX centrality classes of events have been defined by the multiplicity in certain phase space region. A decrease of participant number fluctuations (and thus volume fluctuations) in more central collisions for both experiments has been obtained. Another area of this work addresses to transport model calculations of multiplicity fluctuations in nucleus-nucleus collisions as a function of colliding energy and system size. This study is in full correspondence to the experimental program of the NA61 Collaboration at the SPS. Central C+C, S+S, In+In, and Pb+Pb nuclear collisions at Elab = 10, 20, 30, 40, 80, 158 AGeV have been investigated. The expected enhanced fluctuations - attributed to the critical point and phase transition - can be observed experimentally on top of a monotonic and smooth 'hadronic background'. These findings should be helpful for the optimal

Fluctuations and correlations in nucleus-nucleus collisions within transport approaches

Energy Technology Data Exchange (ETDEWEB)

Konchakovski, Volodymyr P.

2009-10-01

The current thesis is devoted to a systematic study of fluctuations and correlations in heavy-ion collisions, which might be considered as probes for the phase transition and the critical point in the phase diagram, within the Hadron-String- Dynamics (HSD) microscopic transport approach. This is a powerful tool to study nucleus-nucleus collisions and allows to completely simulate experimental collisions on an event-by-event basis. Thus, the transport model has been used to study fluctuations and correlations including the influence of experimental acceptance as well as centrality, system size and collision energy. The comparison to experimental data can separate the effects induced by a phase transition since there is no phase transition in the HSD version used here. Firstly the centrality dependence of multiplicity fluctuations has been studied. Different centrality selections have been performed in the analysis in correspondence to the experimental situation. For the fixed target experiment NA49 events with fixed numbers of the projectile participants have been studied while in the collider experiment PHENIX centrality classes of events have been defined by the multiplicity in certain phase space region. A decrease of participant number fluctuations (and thus volume fluctuations) in more central collisions for both experiments has been obtained. Another area of this work addresses to transport model calculations of multiplicity fluctuations in nucleus-nucleus collisions as a function of colliding energy and system size. This study is in full correspondence to the experimental program of the NA61 Collaboration at the SPS. Central C+C, S+S, In+In, and Pb+Pb nuclear collisions at Elab = 10, 20, 30, 40, 80, 158 AGeV have been investigated. The expected enhanced fluctuations - attributed to the critical point and phase transition - can be observed experimentally on top of a monotonic and smooth 'hadronic background'. These findings should be helpful for the

The role of the nucleus basalis of Meynert and reticular thalamic nucleus in pathogenesis of genetically determined absence epilepsy in rats : A lesion study

NARCIS (Netherlands)

Berdiev, R. K.; Chepurnov, S. A.; Veening, J. G.; Chepurnova, N. E.; van Luiftelaar, G.

2007-01-01

The role of cholinergic nucleus basalis (of Meynert) and the reticular thalamic nucleus in mechanisms of the generation spontaneous spike-and-wave discharges (SWDs) was investigated in the WAG/Rij rat model of absence epilepsy. Selective lesions were affected by local unilateral intraparenchymal

UV laser radiation alters the embryonic protein profile of adrenal-kidney-gonadal complex and gonadal differentiation in the lizard, Calotes Versicolor.

Science.gov (United States)

Khodnapur, Bharati S; Inamdar, Laxmi S; Nindi, Robertraj S; Math, Shivkumar A; Mulimani, B G; Inamdar, Sanjeev R

2015-02-01

To examine the impact of ultraviolet (UV) laser radiation on the embryos of Calotes versicolor in terms of its effects on the protein profile of the adrenal-kidney-gonadal complex (AKG), sex determination and differentiation, embryonic development and hatching synchrony. The eggs of C. versicolor, during thermo-sensitive period (TSP), were exposed to third harmonic laser pulses at 355 nm from a Q-switched Nd:YAG laser for 180 sec. Subsequent to the exposure they were incubated at the male-producing temperature (MPT) of 25.5 ± 0.5°C. The AKG of hatchlings was subjected to protein analysis by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and to histology. The UV laser radiation altered the expression of the protein banding pattern in the AKG complex of hatchlings and it also affected the gonadal sex differentiation. SDS-PAGE of AKG of one-day-old hatchlings revealed a total of nine protein bands in the control group whereas UV laser irradiated hatchlings expressed a total of seven protein bands only one of which had the same Rf as a control band. The UV laser treated hatchlings have an ovotestes kind of gonad exhibiting a tendency towards femaleness instead of the typical testes. It is inferred that 355 nm UV laser radiation during TSP induces changes in the expression of proteins as well as their secretions. UV laser radiation had an impact on the gonadal differentiation pathway but no morphological anomalies were noticed.

White matter alterations in neurodegenerative and vascular dementia

International Nuclear Information System (INIS)

Supprian, T.; Kessler, H.; Falkai, P.; Retz, W.; Roesler, M.; Grunwald, I.; Reith, W.

2003-01-01

Due to a significant overlap of the two syndromes, differentiation of degenerative dementia of the Alzheimer-type from vascular dementia may be difficult even when imaging studies are available. White matter changes occur in many patients suffering from Alzheimer's disease. Little is known about the impact of white matter changes on the course and clinical presentation of Alzheimer's disease. High sensitivity of MRI in the detection of white matter alterations may account for over-diagnosing vascular dementia. The clinical significance of white matter alterations in dementia is still a matter of debate. The article reviews current concepts about the role of white matter alterations in dementia. (orig.) [de

Protein quality control in the nucleus

DEFF Research Database (Denmark)

Nielsen, Sofie V.; Poulsen, Esben Guldahl; Rebula, Caio A.

2014-01-01

to aggregate, cells have evolved several elaborate quality control systems to deal with these potentially toxic proteins. First, various molecular chaperones will seize the misfolded protein and either attempt to refold the protein or target it for degradation via the ubiquitin-proteasome system...... to be particularly active in protein quality control. Thus, specific ubiquitin-protein ligases located in the nucleus, target not only misfolded nuclear proteins, but also various misfolded cytosolic proteins which are transported to the nucleus prior to their degradation. In comparison, much less is known about...... these mechanisms in mammalian cells. Here we highlight recent advances in our understanding of nuclear protein quality control, in particular regarding substrate recognition and proteasomal degradation....

An Evaluation on the Importance of Phosphotungstic Acid Haematoxyiin (PTAH Staining in Differential Diagnosis of Salivary Gland Neoplasms

Directory of Open Access Journals (Sweden)

E Yazdi

2003-02-01

Full Text Available The differential diagnosis between pleomorphic adenoma, the most common salivary gland neoplasm, microscopically, and two other common salivary gland neoplasms, meaning adenoid cystic carcinoma and mucoepidermoid carcinoma, is difficut.The purpose of this study was to determine the differences between pleomorphic adenoma, adenoid cystic carcinoma and mucoepidermoid carcinoma regarding the staining intensity with PTAH and H&E and also to investigate the relationship between staining intensity with PTAH and malignancy grade in mucoepidermoid carcinoma. 72 paraffin embeded samples including 24 pleomorphic adenoma, 24 adenoid cystic carcinoma and 24 mucoepidermoid carcinoma were selected and stained with PTAH. The staining intensity in total, in nucleus and cytoplasm of tumoral cells were evaluated and compared with H&E staining, statistically. The results were analyzed by Kruskal-Wallis, and Wilcoxon signed ranks tests (P<0.05.The logistic model was presented to predict the degree of malignancies through the assessment of nucleus and cytoplasm staining intensity in tumoral cells, and the patient's age. In this study, a statistically significant relationship was observed between staining intensity by PTAH and H& E in nucleus of tumoral cells in pleomorphic adenoma. Moreover, statistically significant relation between staining intensity by PTAH and H & E in cytoplasm of tumoral cells in adenoid cystic carcinoma was found. But there was no relation in other cases. On the other hand, a statistically significant relation between intensity of staining in total, in nucleus and cytoplasm of tumoral cells and the type of tumor was found. No relation was obtained between malignancy grade of mucoepidermoid carcinoma and staining intensity in total, in nucleus and cytoplasm of tumoral cells. The presented logistic model indicated a direct relation between tumor malignancy with patient's age and staining intensity in nucleus of tumoral cells, but a

Collision dynamics and particle production in relativistic nucleus- nucleus collisions at CERN

International Nuclear Information System (INIS)

Harris, J.W.

1990-03-01

The possibility of forming a quark-gluon plasma is the primary motivation for studying nucleus-nucleus collisions at very high energies. Various ''signatures'' for the existence of a quark-gluon plasma in these collisions have been proposed. These include an enhancement in the production of strange particles, suppression of J/Ψ production, observation of direct photons from the plasma, event-by-event fluctuations in the rapidity distributions of produced particles, and various other observables. However, the system will evolve dynamically from a pure plasma or mixed phase through expansion, cooling, hadronization and freezeout into the final state particles. Therefore, to be able to determine that a new, transient state of matter has been formed it will be necessary to understand the space-time evolution of the collision process and the microscopic structure of hadronic interactions, at the level of quarks and gluons, at high temperatures and densities. In this talk I will review briefly the present state of our understanding of the dynamics of these collisions and, in addition, present a few recent results on particle production from the NA35 experiment at CERN. 21 refs., 5 figs

Experimental problems of search for quark-gluon plasma in nucleus-nucleus interactions

International Nuclear Information System (INIS)

Okonov, Eh.O.

1987-01-01

Experimental problems for searching for quark-gluon (quagma) plasma in nucleus-nucleus interactions (NbNb,CaCa, ArPb, CnE, ONe) in the energy range E=0.4-1 GeV/A and 3.67 GeV/A and 200 GeV/A energies are discussed. Peculiarities of performing experiments on Dubna synchrophasotron and SPS Bevalac are discussed. The first results prove hadron matter thermalization sufficient for quagma manifestation. It is found that such characteristics of studied interactions as relative λ-hyperon yield, spectral (temperature) characteristics of λ k -hyperons (with higher values of transferred transverse momenta) and associatively produced peons are of greatest interest. The necessity of precise establishment of λ-hyperon group as excessive and differing in its origin from the other particles of the hadron phase is noted. It is shown that experimental approach used in Dubna research proved efficient and requires further development. It includes : selection of rare events (fluctuations) in central interactions of nuclei with high local excitation; search and research of peculiarities in the production of strange particles and in associative pion production; use of streamer spectrometer with a trigger system of rigid selection of central interactions

Preliminary experimental insights into differential heat impact among lithic artifacts

Directory of Open Access Journals (Sweden)

Guillermo Bustos-Pérez

2016-09-01

Full Text Available The presence of thermally altered and broken flint artifacts is common at archaeological sites. Most studies focus their attention on the effects of heat treatment on flint to improve knapping qualities, disregarding the effects of fire over flint under uncontrolled conditions. This paper aims to show how under uncontrolled heating processes flint artifacts develop different heat alterations (such as levels of breakage, presence of scales, etc. as a result of vertical distribution, volume or raw material and to establish a gradient of rock changes and behavior. Artifacts where macroscopically analyzed and a series of uncontrolled heating experiments through the distribution of flint blanks under two hearths were carried out, allowing a comparison of the before and after of the blanks. Preliminary results show how levels of breakage, surface alteration or development of heat alteration features can be differentiated according to artifact volume, vertical distribution and level of surface alteration. Results also show how two different raw materials react differently to similar thermal impact, and how surface alteration reacts at different rhythm in the case of recycled artifacts. We conclude that levels of thermal alteration can be differentiated through macroscopic analysis of flint surface.

Cochlear nucleus neuron analysis in individuals with presbycusis.

Science.gov (United States)

Hinojosa, Raul; Nelson, Erik G

2011-12-01

The aim of this study was to analyze the cochlear nucleus neuron population in individuals with normal hearing and presbycusis. Retrospective study of archival human temporal bone and brain stem tissues. Using strict inclusion criteria, the temporal bones and cochlear nuclei from six normal hearing individuals and four individuals with presbycusis were selected for analysis. The spiral ganglion cell population, the cochlear nucleus neuron population, and the cell body size of the neurons were quantified in these cases. A relationship was not observed between age and the spiral ganglion cell population in the normal hearing group. Presbycusis subjects exhibited a reduced spiral ganglion cell population. The mean cochlear nucleus neuron population was observed to be significantly higher in the presbycusis group (mean ± standard deviation: 114,170 ± 10,570) compared to the normal hearing group (91,470 ± 9,510) (P = .019). This difference was predominantly the result of greater multipolar and granule cell neuron populations. Only the fusiform neuron type exhibited a significantly different mean cell body cross-sectional area between the normal hearing group (242 ± 27) and the presbycusis group (300 ± 37) (P = .033). This investigation is the first time, to our knowledge, that the populations of the eight neuron types in the cochlear nucleus have been quantified in both normal hearing individuals and individuals with presbycusis. The data support the concept that presbycusis is not an effect of aging alone but instead may be a condition that predisposes one to hearing loss with advancing age and is characterized by a congenitally elevated cochlear nucleus neuron population. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

The nucleus as a laboratory

International Nuclear Information System (INIS)

Blin-Stoyle, R.J.

1979-01-01

The nucleus is a complicated many-body structure whose properties when carefully studied can frequently give important information about the underlying elementary particle interactions. This article reviews progress in research of this kind over the last twenty-five years. (author)

Percolation picture of disintegration of nuclei in the proton-nucleus interaction

International Nuclear Information System (INIS)

Botvina, A.S.; Lanin, L.V.

1992-01-01

Breakup of nuclei into fragments in the proton-nucleus interaction is studied. It is assumed that breakup occurs in two stages. During the first stage the incident particle interacts with individual nucleons of the nucleus, and high-energy reaction products are emitted from the nucleus. This stage is described by means of the intranuclear-cascade model. During the second stage some of the nuclei, whose excitation energy is high, or whose density is very inhomogeneous, break up. This breakup is described by means of a percolation model which takes into account the spatial distribution of nucleons in the nucleus and which generalizes the percolation description of the 'liquid-gas' phase transition for finite nuclei. Features of this breakup mechanism are studied. The analysis of the experimental data indicates that it is not sufficient to consider percolation only in the coordinate space, and that the momentum distribution of the nucleons in the nucleus must be taken into account

Differential courtship activity and alterations of reproductive success of competing gupply males as an indicator for low concentrations of aquatic pollutants

Energy Technology Data Exchange (ETDEWEB)

Schroeder, J.H.; Peters, K.

1988-09-01

Differential courtship activity of guppy males competing for the same females was used as a bioindicator for low concentrations of water-borne pollutants in a previous study. Patterns of male sexual activity were chosen because they determine reproductive success. The mean difference between courtship activities of two male competitors determines the relative fitness of the male in question. Accordingly, the decrease in mean differential courtship after exposure to aquatic contaminants was predicted to cause a corresponding change in the relative reproductive success. The present study completed the previous one by repeating the experiment with a 10% addition of wastewater drawn from the last clearing basin of a Munich purification plant this time using virgin (non-inseminated) females which were receptive to male courtship. The females subsequently were allowed to produce as many offspring as possible. The number of young guppies sired by individual male competitors could easily be traced by the use of sex-linked phenotypic color patterns as markers. The purpose of these two studies was to show that the quantification of sexual activities of male guppies is useful for monitoring environmental alterations which affect fitness characters.

Circadian rhythm of mechanically mediated differentiation of osteoblasts

Science.gov (United States)

Roberts, W. E.; Mozsary, P. G.; Klingler, E.

1984-01-01

The differential of osteoblasts in response to orthodontic pressure in the periodontal ligament of the maxillary-first-molar periodontal ligaments of 12-h-light/dark-entrained 7-wk-old male Simonsen outbred rats is measured by (H-3)-Thymidine nuclear-volume morphometry (Roberts et al., 1983) at hourly intervals throughout the circadian cycle. The results are presented in graphs and discussed. Preosteoblast large nuclei (D-cells) are found to synthesize DNA mainly in light and to divide in the following dark period, while small-nucleus osteoprogenitors (A-cells) synthesize in darkness and divide in light. These findings are seen as consistent with a model in which the sequence of proliferation and differentiation requires at least 60 h (five 12-h periods) and the shift from A to D cells lasts about 19 h.

Molecular orbitals of nucleons in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Imanishi, B.; Oertzen, W. von.

1986-05-01

A formalism for the dynamical treatment of the molecular orbitals of valence nucleons in nucleus-nucleus collisions at low bombarding energy is developed with the use of the coupled-reaction-channel (CRC) method. The Coriolis coupling effects as well as the finite mass effects of the nucleon are taken into account in this model, of rotating molecular orbitals, RMO. First, the validity of the concept is examined from the view point of the multi-step processes in a standard CRC calculation for systems containing two identical [core] nuclei. The calculations show strong CRC effects particularly in the case where the mixing of different l-parity orbitals - called hybridization in atomic physics - occurs. Then, the RMO representation for active nucleons is applied to the same systems and compared to the CRC results. Its validity is investigated with respect to the radial motion (adiabaticity) and the rotation of the molecular axis (radial and rotational coupling). Characteristic molecular orbitals of covalent molecules appear as rotationally stable states (K = 1/2) with good adiabaticity. Using the RMO's we obtain a new interpretation of various scattering phenomena. Dynamically induced changes in the effective Q-values (or scaling of energies), dynamically induced moments of inertia and an dynamically induced effective (L · S) interaction are obtained as a result of the molecular orbital formation. Various experimental data on transfer and subbarrier fusion reactions are understood in terms of the RMO's and their adiabatic potentials. Landau-Zener transitions, which strongly depend on the total angular momentum of the system, definitely predict the observation of characteristic changes in the cross sections for the inelastic scattering 13 C( 12 C, 12 C) 13 C* (3.086 MeV, 1/2 + ) with the change of the bombarding energy. (author)

Olanzapine Overdose in a Pin Point Pupil with Altered Sensorium

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Naresh Midha

2017-09-01

Full Text Available Background:Olanzapine is a highly tolerable and easily affordable atypical antipsychotic drug which has been commonly prescribed in both inpatient and outpatient settings for several mental disorders. Olanzapine overdose is commonly seen in psychiatric patients, who attempt suicide by intoxicating themselves with their own prescribed medications. Increased olanzapine use is associated with increased incidence of overdosing. Case Presentation:We are reporting a case of olanzapine overdosage as a cause of pinpoint pupils and altered sensorium with exclusion of other differentials. The mainstay of managementof olanzapine overdose is general supportive and symptomatic measures. Discussion: Pinpoint pupils with altered sensorium and agitation are always an alarming situation for a clinician, because of differentials like organophosphorus poisoning, pontine hemorrhage and opium overdosing. Due to olanzapine overdosage, similar clinical picture can be confusing in the emergency department and early identification of such cases is helpful to decrease the risk of fatality. Conclusion: This case highlights the significance of olanzapine overdosing as a differential diagnosis for patients presented with altered sensorium and pinpoint pupils in the emergency department. Olanzapine overdosage is associated with high morbidity and mortality. Although there is no specific antidote for olanzapine overdose, appropriate history, assessment and early diagnosis are very useful for the better outcome.

White-throated sparrows alter songs differentially in response to chorusing anurans and other background noise.

Science.gov (United States)

Lenske, Ariel K; La, Van T

2014-06-01

Animals can use acoustic signals to attract mates and defend territories. As a consequence, background noise that interferes with signal transmission has the potential to reduce fitness, especially in birds that rely on song. While much research on bird song has investigated vocal flexibility in response to urban noise, weather and other birds, the possibility of inter-class acoustic competition from anurans has not been previously studied. Using sound recordings from central Ontario wetlands, we tested if white-throated sparrows (Zonotrichia albicolis) make short-term changes to their singing behaviour in response to chorusing spring peepers (Pseudacris crucifer), as well as to car noise, wind and other bird vocalizations. White-throated sparrow songs that were sung during the spring peeper chorus were shorter with higher minimum frequencies and narrower bandwidths resulting in reduced frequency overlap. Additionally, sparrows were less likely to sing when car noise and the vocalizations of other birds were present. These patterns suggest that birds use multiple adjustment strategies. This is the first report to demonstrate that birds may alter their songs differentially in response to different sources of noise. This article is part of a Special Issue entitled: insert SI title. Copyright © 2014 Elsevier B.V. All rights reserved.

Nuclear sizes and intranuclear matter distribution -- from hadron-nucleus collisions

International Nuclear Information System (INIS)

Strugalska-Gola, E.; Strugalski, Z.

1999-01-01

The method of intranuclear matter studies by hadronic projectiles is found and worked out. It is tested on the pion-xenon nucleus collision events. Target-nucleus size and nucleon density distributions in it were estimated and described by formulas prompted experimentally

Differential metamorphosis alters the endocrine response in anuran larvae exposed to T{sub 3} and atrazine

Energy Technology Data Exchange (ETDEWEB)

Freeman, Jennifer L. [University of Illinois, Department of Crop Sciences, 1201 W. Gregory Drive, 320 ERML, Urbana, IL 61801 (United States); Beccue, Nathan [University of Illinois, Department of Crop Sciences, 1201 W. Gregory Drive, 320 ERML, Urbana, IL 61801 (United States); Rayburn, A. Lane [University of Illinois, Department of Crop Sciences, 1201 W. Gregory Drive, 320 ERML, Urbana, IL 61801 (United States)]. E-mail: arayburn@uiuc.edu

2005-11-10

Pesticide chemical contamination is one of the suspected contributors of the amphibian population decline. The herbicide atrazine is one of the major surface water contaminants in the U.S. A previous study has shown that atrazine at concentrations as low as 100 parts per billion (ppb) increased the time to metamorphosis in Xenopus laevis tadpoles. However, questions remain as to the applicability of a study of a non-native species to a native organism. The possible effects of atrazine on developing Bufo americanus were explored. Atrazine at potentially (albeit high) environmental concentrations was found not to delay the metamorphosis of developing B. americanus tadpoles as observed in X. laevis. Several studies have indicated that atrazine affects thyroid hormones. Since thyroid hormones are critical in amphibian metamorphosis, B. americanus and X. laevis tadpoles were exposed to exogenous 3,5,3'-triiodothyronine (T{sub 3}). X. laevis were found to be more responsive to the effects of exogenous T{sub 3} compared to B. americanus, indicating that X. laevis may be more sensitive to endocrine active chemicals than B. americanus. In X. laevis, nuclear heterogeneity has been associated with metamorphosis. Flow cytometric analysis of the nuclei of normal metamorphing B. americanus indicates a decrease in the amount of thyroid mediated chromatin alterations relative to the nuclei of metamorphing X. laevis. Indications are that the differential response to endocrine disruption is due to the differential role of chromatin associated gene expression during metamorphosis of B. americanus versus X. laevis. A second native species, Hyla versicolor, was observed to have the X. laevis nuclear pattern with respect to metamorphosis. As such, sensitivity to endocrine disruption is hypothesized not to be limited to laboratory non-native species.

Altered level of consciousness: evidence-based management in the emergency department [digest].

Science.gov (United States)

Song, Joo Lee; Wang, Vincent J; Vazquez, Michelle N

2017-01-22

A child who presents to the emergency department with an altered level of consciousness can be clinically unstable and can pose a great diagnostic challenge. The emergency clinician must quickly develop a wide differential of possible etiologies in order to administer potentially life-saving medications or interventions. The history, physical examination, and appropriate diagnostic tests can aid greatly in rapidly narrowing the differential diagnosis. Once initial stabilization, workup, and first-line interventions are completed, most patients who present with unresolved or unidentified altered level of consciousness should be admitted for further evaluation and close monitoring. This issue provides a review of the etiologies of altered level of consciousness as well as guidance for the management and disposition of patients with this condition. [Points & Pearls is a digest of Pediatric Emergency Medicine Practice].

Altered ubiquitin causes perturbed calcium homeostasis, hyperactivation of calpain, dysregulated differentiation, and cataract.

Science.gov (United States)

Liu, Ke; Lyu, Lei; Chin, David; Gao, Junyuan; Sun, Xiurong; Shang, Fu; Caceres, Andrea; Chang, Min-Lee; Rowan, Sheldon; Peng, Junmin; Mathias, Richard; Kasahara, Hideko; Jiang, Shuhong; Taylor, Allen

2015-01-27

Although the ocular lens shares many features with other tissues, it is unique in that it retains its cells throughout life, making it ideal for studies of differentiation/development. Precipitation of proteins results in lens opacification, or cataract, the major blinding disease. Lysines on ubiquitin (Ub) determine fates of Ub-protein substrates. Information regarding ubiquitin proteasome systems (UPSs), specifically of K6 in ubiquitin, is undeveloped. We expressed in the lens a mutant Ub containing a K6W substitution (K6W-Ub). Protein profiles of lenses that express wild-type ubiquitin (WT-Ub) or K6W-Ub differ by only ∼2%. Despite these quantitatively minor differences, in K6W-Ub lenses and multiple model systems we observed a fourfold Ca(2+) elevation and hyperactivation of calpain in the core of the lens, as well as calpain-associated fragmentation of critical lens proteins including Filensin, Fodrin, Vimentin, β-Crystallin, Caprin family member 2, and tudor domain containing 7. Truncations can be cataractogenic. Additionally, we observed accumulation of gap junction Connexin43, and diminished Connexin46 levels in vivo and in vitro. These findings suggest that mutation of Ub K6 alters UPS function, perturbs gap junction function, resulting in Ca(2+) elevation, hyperactivation of calpain, and associated cleavage of substrates, culminating in developmental defects and a cataractous lens. The data show previously unidentified connections between UPS and calpain-based degradative systems and advance our understanding of roles for Ub K6 in eye development. They also inform about new approaches to delay cataract and other protein precipitation diseases.

Differential splicing and glycosylation of Apoer2 alters synaptic plasticity and fear learning.

Science.gov (United States)

Wasser, Catherine R; Masiulis, Irene; Durakoglugil, Murat S; Lane-Donovan, Courtney; Xian, Xunde; Beffert, Uwe; Agarwala, Anandita; Hammer, Robert E; Herz, Joachim

2014-11-25

Apoer2 is an essential receptor in the central nervous system that binds to the apolipoprotein ApoE. Various splice variants of Apoer2 are produced. We showed that Apoer2 lacking exon 16, which encodes the O-linked sugar (OLS) domain, altered the proteolytic processing and abundance of Apoer2 in cells and synapse number and function in mice. In cultured cells expressing this splice variant, extracellular cleavage of OLS-deficient Apoer2 was reduced, consequently preventing γ-secretase-dependent release of the intracellular domain of Apoer2. Mice expressing Apoer2 lacking the OLS domain had increased Apoer2 abundance in the brain, hippocampal spine density, and glutamate receptor abundance, but decreased synaptic efficacy. Mice expressing a form of Apoer2 lacking the OLS domain and containing an alternatively spliced cytoplasmic tail region that promotes glutamate receptor signaling showed enhanced hippocampal long-term potentiation (LTP), a phenomenon associated with learning and memory. However, these mice did not display enhanced spatial learning in the Morris water maze, and cued fear conditioning was reduced. Reducing the expression of the mutant Apoer2 allele so that the abundance of the protein was similar to that of Apoer2 in wild-type mice normalized spine density, hippocampal LTP, and cued fear learning. These findings demonstrated a role for ApoE receptors as regulators of synaptic glutamate receptor activity and established differential receptor glycosylation as a potential regulator of synaptic function and memory. Copyright © 2014, American Association for the Advancement of Science.

Production of Kaon and Λ in Nucleus-Nucleus Collisions at Ultrarelativistic Energy from a Blast-Wave Model

International Nuclear Information System (INIS)

Chen, J. H.; Zhang, S.; Ma, Y. G.; Zhong, C.

2015-01-01

The particle production of Kaon and Λ is studied in nucleus-nucleus collisions at relativistic energy based on a chemical equilibrium blast-wave model. The transverse momentum spectra of Kaon and Λ at the kinetic freeze-out stage from our model are in good agreement with the experimental results. The kinetic freeze-out parameters of temperature (T kin ) and radial flow parameter ρ 0 are presented for the FOPI, RHIC, and LHC energies. And the resonance decay effect is also discussed. The systematic study for beam energy dependence of the strangeness particle production will help us to better understand the properties of the matter created in heavy-ion collisions at the kinetic freeze-out stage

Raman microspectroscopy of nucleus and cytoplasm for human colon cancer diagnosis.

Science.gov (United States)

Liu, Wenjing; Wang, Hongbo; Du, Jingjing; Jing, Chuanyong

2017-11-15

Subcellular Raman analysis is a promising clinic tool for cancer diagnosis, but constrained by the difficulty of deciphering subcellular spectra in actual human tissues. We report a label-free subcellular Raman analysis for use in cancer diagnosis that integrates subcellular signature spectra by subtracting cytoplasm from nucleus spectra (Nuc.-Cyt.) with a partial least squares-discriminant analysis (PLS-DA) model. Raman mapping with the classical least-squares (CLS) model allowed direct visualization of the distribution of the cytoplasm and nucleus. The PLS-DA model was employed to evaluate the diagnostic performance of five types of spectral datasets, including non-selective, nucleus, cytoplasm, ratio of nucleus to cytoplasm (Nuc./Cyt.), and nucleus minus cytoplasm (Nuc.-Cyt.), resulting in diagnostic sensitivity of 88.3%, 84.0%, 98.4%, 84.5%, and 98.9%, respectively. Discriminating between normal and cancerous cells of actual human tissues through subcellular Raman markers is feasible, especially when using the nucleus-cytoplasm difference spectra. The subcellular Raman approach had good stability, and had excellent diagnostic performance for rectal as well as colon tissues. The insights gained from this study shed new light on the general applicability of subcellular Raman analysis in clinical trials. Copyright © 2017 Elsevier B.V. All rights reserved.

The suprachiasmatic nucleus-paraventricular nucleus interactions: a bridge to the neuroendocrine and autonomic nervous system

NARCIS (Netherlands)

Buijs, R. M.; Hermes, M. H.; Kalsbeek, A.

1998-01-01

Vasopressin (VP) is one of the principal neurotransmitters of the suprachiasmatic nucleus (SCN). By means of anatomical, physiological and electrophysiological techniques we have demonstrated that VP containing pathways from the SCN serve to affect neuroendocrine and 'autonomic' neurons in the

High energy hadron-nucleus scattering

International Nuclear Information System (INIS)

Koplik, J.; Mueller, A.H.

1975-01-01

Theoretical expectations for hadron-nucleus scattering at high energy if the basic hadron-hadron interaction is due to Regge poles and cuts arising in multiperipheral or soft field theory models are described. Experiments at Fermilab may provide a critical test of such models

Sustained alterations of hypothalamic tanycytes during posttraumatic hypopituitarism in male mice.

Science.gov (United States)

Osterstock, Guillaume; El Yandouzi, Taoufik; Romanò, Nicola; Carmignac, Danielle; Langlet, Fanny; Coutry, Nathalie; Guillou, Anne; Schaeffer, Marie; Chauvet, Norbert; Vanacker, Charlotte; Galibert, Evelyne; Dehouck, Bénédicte; Robinson, Iain C A F; Prévot, Vincent; Mollard, Patrice; Plesnila, Nikolaus; Méry, Pierre-François

2014-05-01

Traumatic brain injury is a leading cause of hypopituitarism, which compromises patients' recovery, quality of life, and life span. To date, there are no means other than standardized animal studies to provide insights into the mechanisms of posttraumatic hypopituitarism. We have found that GH levels were impaired after inducing a controlled cortical impact (CCI) in mice. Furthermore, GHRH stimulation enhanced GH to lower level in injured than in control or sham mice. Because many characteristics were unchanged in the pituitary glands of CCI mice, we looked for changes at the hypothalamic level. Hypertrophied astrocytes were seen both within the arcuate nucleus and the median eminence, two pivotal structures of the GH axis, spatially remote to the injury site. In the arcuate nucleus, GHRH neurons were unaltered. In the median eminence, injured mice exhibited unexpected alterations. First, the distributions of claudin-1 and zonula occludens-1 between tanycytes were disorganized, suggesting tight junction disruptions. Second, endogenous IgG was increased in the vicinity of the third ventricle, suggesting abnormal barrier properties after CCI. Third, intracerebroventricular injection of a fluorescent-dextran derivative highly stained the hypothalamic parenchyma only after CCI, demonstrating an increased permeability of the third ventricle edges. This alteration of the third ventricle might jeopardize the communication between the hypothalamus and the pituitary gland. In conclusion, the phenotype of CCI mice had similarities to the posttraumatic hypopituitarism seen in humans with intact pituitary gland and pituitary stalk. It is the first report of a pathological status in which tanycyte dysfunctions appear as a major acquired syndrome.

Exotic behavior of elastic scattering differential cross-sections of weakly bound nucleus 17F at small angles

International Nuclear Information System (INIS)

Han Jianlong; Hu Zhengguo; Zhang Xueyin; Yuan Xiaohua; Xu Huagen; Qi Huirong; Wang Yue; Jia Fei; Wu Lijie; Ding Xianli; Gao Qi; Gao Hui; Bai Zhen

2006-01-01

The differential cross-sections for elastic scattering of 17 F and 17 O on 208 Pb have been measured at Radioactive Ion Beam Line at Lanzhou (RIBLL). The variation of the logarithms of differential cross-sections with the square of scattering angles shows clearly that there exists a turning point in the range of small scattering angles (6 degree-20 degree) for 17 F having exotic structure, while no turning point was observed in the 17 O elastic scattering. The experimental results have been compared with previous data. Systematical analysis on the available data seems to conclude that there is an exotic behavior of elastic scattering differential cross-sections of weakly bound nuclei with halo or skin structure as compared with that of the ordinary nuclei near stable line. Therefore the fact that the turning point of the logarithms of differential cross-sections appears at small angle for weakly bound nuclei could be used as a new probe to investigate the halo and skin phenomenon. (authors)

Hummingbird Comet Nucleus Analysis Mission

Science.gov (United States)

Kojiro, Daniel; Carle, Glenn C.; Lasher, Larry E.

2000-01-01

Hummingbird is a highly focused scientific mission, proposed to NASA s Discovery Program, designed to address the highest priority questions in cometary science-that of the chemical composition of the cometary nucleus. After rendezvous with the comet, Hummingbird would first methodically image and map the comet, then collect and analyze dust, ice and gases from the cometary atmosphere to enrich characterization of the comet and support landing site selection. Then, like its namesake, Hummingbird would carefully descend to a pre-selected surface site obtaining a high-resolution image, gather a surface material sample, acquire surface temperature and then immediately return to orbit for detailed chemical and elemental analyses followed by a high resolution post-sampling image of the site. Hummingbird s analytical laboratory contains instrumentation for a comprehensive molecular and elemental analysis of the cometary nucleus as well as an innovative surface sample acquisition device.

A morphometric, immunohistochemical, and in situ hybridization study of the dorsal raphe nucleus in major depression, bipolar disorder, schizophrenia, and suicide.

Science.gov (United States)

Matthews, Paul R; Harrison, Paul J

2012-03-01

Several lines of evidence implicate 5-hydroxytryptamine (5-HT, serotonin) in the pathophysiology of mood disorders and suicide. However, it is unclear whether these conditions include morphological involvement of the dorsal raphe nucleus (DRN), the origin of most forebrain 5-HT innervation. We used morphometric, immunohistochemical, and molecular methods to compare the DRN in post-mortem tissue of 50 subjects (13 controls, 14 major depressive disorder [MDD], 13 bipolar disorder, 10 schizophrenia; 17 of the cases died by suicide). NeuN and PH8 antibodies were used to assess all neurons and serotonergic neurons respectively; 5-HT(1A) autoreceptor expression was investigated by regional and cellular in situ hybridization. Measurements were made at three rostrocaudal levels of the DRN. In MDD, the area of the DRN was decreased. In bipolar disorder, serotonergic neuronal size was decreased. Suicide was associated with an increased DRN area, and with a higher density but decreased size of serotonergic neurons. Total neuronal density and 5-HT(1A) receptor mRNA abundance were unaffected by diagnosis or suicide. No changes were seen in schizophrenia. The results show that mood disorders and suicide are associated with differential, limited morphological alterations of the DRN. The contrasting influences of MDD and suicide may explain some of the discrepancies between previous studies, since their design precluded detection of the effect. Copyright © 2011 Elsevier B.V. All rights reserved.

Particle spectra and correlations in sulfur-nucleus reactions at 200 GeV per nucleon

International Nuclear Information System (INIS)

Alber, T.

1995-08-01

In this work the production of negatively charged particles and two-particle correlations in nucleus-nucleus reactions at high energies are studied. The range of the acceptance of experiment NA35 at the CERN-SPS was increased in 1990 by adding a large volume Time Projection Chamber downstream of the streamer chamber. The analysis of the data taken during the run period 1991 shows that such a detector faces no basic problems when operated in a high multiplicity experiment. The scenario of particle production in sulfur-nucleus reactions is studied via the measurement of rapidity and transverse momentum distributions which show good agreement with the results from other data-sets of the same experiment. The width of the rapidity distribution is only a little narrower than observed in nucleon-nucleon collisions and is in contradiction to the assumption of a static source with isotropic particle emission. The shape of the transverse momentum distribution indicates an effective temperature at freeze-out of about 150 MeV. The analysis of the two-particle correlation benefits particularly from the high statistics collected for different reactions in different phase-space regions. This allows a differential analysis of the correlation function for the different components of the momentum difference in various regions of rapidity and transverse momentum. It is recalled that for an expanding source the experimentally obtained radius parameters are not a direct measure of the geometrical size of the source but measure a so-called region of homogeneity. This expectation is also confirmed by a microscopic simulation of the reaction. The experimental results for the radius parameters support such a description of the particle production mechanism in terms of an expanding source. (orig.)

Nucleus retroambiguus projections to the periaqueductal gray in the cat

NARCIS (Netherlands)

Klop, EM; Mouton, LJ; Holstege, G

2002-01-01

The nucleus retroambiguus (NRA) of the caudal medulla is a relay nucleus by which neurons of the mesencephalic periaqueductal gray (PAG) reach motoneurons of pharynx, larynx, soft palate, intercostal and abdominal muscles, and several muscles of the hindlimbs. These PAG-NRA-motoneuronal projections

ENVIRONMENTAL ANTIANDROGENS: LOW DOSES OF VINCLOZOLIN ALTER SEXUAL DIFFERENTIATION OF THE MALE RAT

Science.gov (United States)

In humans and rodents, exposure to antiandrogenic chemicals during sexual differentiation can produce malformations of the reproductive tract. Perinatal administration of 100 or 200 mg vinclozolin (V) kg-1 day-1 during sexual differentiation in rats induces female-like anogenital...

Tumor-altered dendritic cell function: implications for anti-tumor immunity

Directory of Open Access Journals (Sweden)

Kristian Michael Hargadon

2013-07-01

Full Text Available Dendritic cells are key regulators of both innate and adaptive immunity, and the array of immunoregulatory functions exhibited by these cells is dictated by their differentiation, maturation, and activation status. Although a major role for these cells in the induction of immunity to pathogens has long been appreciated, data accumulated over the last several years has demonstrated that DC are also critical regulators of anti-tumor immune responses. However, despite the potential for stimulation of robust anti-tumor immunity by DC, tumor-altered DC function has been observed in many cancer patients and tumor-bearing animals and is often associated with tumor immune escape. Such dysfunction has significant implications for both the induction of natural anti-tumor immune responses as well as the efficacy of immunotherapeutic strategies that target endogenous DC in situ or that employ exogenous DC as part of anti-cancer immunization maneuvers. In this review, the major types of tumor-altered DC function will be described, with emphasis on recent insights into the mechanistic bases for the inhibition of DC differentiation from hematopoietic precursors, the altered programming of DC precursors to differentiate into myeloid-derived suppressor cells or tumor-associated macrophages, the suppression of DC maturation and activation, and the induction of immunoregulatory DC by tumors, tumor-derived factors, and tumor-associated cells within the milieu of the tumor microenvironment. The impact of these tumor-altered cells on the quality of the overall anti-tumor immune response will also be discussed. Finally, this review will also highlight questions concerning tumor-altered DC function that remain unanswered, and it will address factors that have limited advances in the study of this phenomenon in order to focus future research efforts in the field on identifying strategies for interfering with tumor-associated DC dysfunction and improving DC-mediated anti

A parton description of the nucleus fragmentation region in heavy-ion collisions

International Nuclear Information System (INIS)

Hwa, R.C.; Oregon Univ., Eugene

1984-01-01

In nucleus-nucleus collisions, the rapidity distribution of partons in the nucleus fragmentation region is highly asymmetrical. Thermalization that randomizes the momenta of partons far apart in rapidity cannot be expected. A local thermalization model is introduced which relates temperature to the range of parton interaction in rapidity. The parton number density and energy density are then calculated. (orig.)

Comparison of Hi-C results using in-solution versus in-nucleus ligation.

Science.gov (United States)

Nagano, Takashi; Várnai, Csilla; Schoenfelder, Stefan; Javierre, Biola-Maria; Wingett, Steven W; Fraser, Peter

2015-08-26

Chromosome conformation capture and various derivative methods such as 4C, 5C and Hi-C have emerged as standard tools to analyze the three-dimensional organization of the genome in the nucleus. These methods employ ligation of diluted cross-linked chromatin complexes, intended to favor proximity-dependent, intra-complex ligation. During development of single-cell Hi-C, we devised an alternative Hi-C protocol with ligation in preserved nuclei rather than in solution. Here we directly compare Hi-C methods employing in-nucleus ligation with the standard in-solution ligation. We show in-nucleus ligation results in consistently lower levels of inter-chromosomal contacts. Through chromatin mixing experiments we show that a significantly large fraction of inter-chromosomal contacts are the result of spurious ligation events formed during in-solution ligation. In-nucleus ligation significantly reduces this source of experimental noise, and results in improved reproducibility between replicates. We also find that in-nucleus ligation eliminates restriction fragment length bias found with in-solution ligation. These improvements result in greater reproducibility of long-range intra-chromosomal and inter-chromosomal contacts, as well as enhanced detection of structural features such as topologically associated domain boundaries. We conclude that in-nucleus ligation captures chromatin interactions more consistently over a wider range of distances, and significantly reduces both experimental noise and bias. In-nucleus ligation creates higher quality Hi-C libraries while simplifying the experimental procedure. We suggest that the entire range of 3C applications are likely to show similar benefits from in-nucleus ligation.

Effect of cochlear nerve electrocautery on the adult cochlear nucleus.

Science.gov (United States)

Iseli, Claire E; Merwin, William H; Klatt-Cromwell, Cristine; Hutson, Kendall A; Ewend, Matthew G; Adunka, Oliver F; Fitzpatrick, Douglas C; Buchman, Craig A

2015-04-01

Electrocauterization and subsequent transection of the cochlear nerve induce greater injury to the cochlear nucleus than sharp transection alone. Some studies show that neurofibromatosis Type 2 (NF2) patients fit with auditory brainstem implants (ABIs) fail to achieve speech perception abilities similar to ABI recipients without NF2. Reasons for these differences remain speculative. One hypothesis posits poorer performance to surgically induced trauma to the cochlear nucleus from electrocautery. Sustained electrosurgical depolarization of the cochlear nerve may cause excitotoxic-induced postsynaptic nuclear injury. Equally plausible is that cautery in the vicinity of the cochlear nucleus induces necrosis. The cochlear nerve was transected in anesthetized adult gerbils sharply with or without bipolar electrocautery at varying intensities. Gerbils were perfused at 1, 3, 5, and 7 days postoperatively; their brainstem and cochleas were embedded in paraffin and sectioned at 10 μm. Alternate sections were stained with flourescent markers for neuronal injury or Nissl substance. In additional experiments, anterograde tracers were applied directly to a sectioned eighth nerve to verify that fluorescent-labeled profiles seen were terminating auditory nerve fibers. Cochlear nerve injury was observed from 72 hours postoperatively and was identical across cases regardless of surgical technique. Postsynaptic cochlear nucleus injury was not seen after distal transection of the nerve. By contrast, proximal transection was associated with trauma to the cochlear nucleus. Distal application of bipolar electrocautery seems safe for the cochlear nucleus. Application near the root entry zone must be used cautiously because this may compromise nuclear viability needed to support ABI stimulation.

Nuclear matrix - structure, function and pathogenesis.

Science.gov (United States)

Wasąg, Piotr; Lenartowski, Robert

2016-12-20

The nuclear matrix (NM), or nuclear skeleton, is the non-chromatin, ribonucleoproteinaceous framework that is resistant to high ionic strength buffers, nonionic detergents, and nucleolytic enzymes. The NM fulfills a structural role in eukaryotic cells and is responsible for maintaining the shape of the nucleus and the spatial organization of chromatin. Moreover, the NM participates in several cellular processes, such as DNA replication/repair, gene expression, RNA transport, cell signaling and differentiation, cell cycle regulation, apoptosis and carcinogenesis. Short nucleotide sequences called scaffold/matrix attachment regions (S/MAR) anchor the chromatin loops to the NM proteins (NMP). The NMP composition is dynamic and depends on the cell type and differentiation stage or metabolic activity. Alterations in the NMP composition affect anchoring of the S/MARs and thus alter gene expression. This review aims to systematize information about the skeletal structure of the nucleus, with particular emphasis on the organization of the NM and its role in selected cellular processes. We also discuss several diseases that are caused by aberrant NM structure or dysfunction of individual NM elements.

Shape study of the N=Z waiting-point nucleus 72Kr via beta decay

CERN Document Server

Briz Monago, Jose Antonio; Nácher González, Enrique

The Ph.D. thesis entitled “Shape study of the N=Z waiting-point nucleus 72Kr via beta decay” is devoted to the study of the shape of the ground state of the 72Kr nucleus. It is an N=Z nucleus in the mass region A~70-80 where shape transitions and the shape coexistence phenomena have been identified. Furthermore, this nucleus participates in the rp-process as a waiting point due to the slowdown of the process taking place at the arrival to this nucleus. The study of the properties of this nucleus is interesting from the Nuclear Structure point of view, for the phenomena occurring in its mass region and have been predicted for it, and from the Nuclear Astrophysics for the accurate performance of astrophysical calculations. The β+/EC decay of the 72Kr nucleus has been studied through two complementary experiments at the ISOLDE facility at CERN in Geneva (Switzerland). In one of them, the low-spin structure of the daughter nucleus, 72Br, has been revised via conversion electron spectroscopy where the convers...

Colour, albedo and nucleus size of Halley's comet

Science.gov (United States)

Cruikshank, D. P.; Tholen, D. J.; Hartmann, W. K.

1985-01-01

Photometry of Halley's comet in the B, J, V, and K broadband filters during a time when the coma was very weak and presumed to contribute negligibly to the broadband photometry is reported. The V-J and J-K colors suggest that the color of the nucleus of Halley's comet is similar to that of the D-type asteroids, which in turn suggests that the surface of the nucleus has an albedo less than 0.1.

The dentate nucleus in children: normal development and patterns of disease

Energy Technology Data Exchange (ETDEWEB)

McErlean, Aoife; Abdalla, Khaled; Donoghue, Veronica; Ryan, Stephanie [Children' s University Hospital, Radiology Department, Dublin (Ireland)

2010-03-15

The dentate nuclei lie deep within the cerebellum and play a vital role in the pathways involved in fine motor control and coordination. They are susceptible to a variety of diseases. Some pathological processes preferentially affect the dentate nuclei, while concomitant basal ganglia or white matter involvement can be a striking finding in others. A familiarity with the normal appearance of the dentate nuclei at different ages in combination with the radiological distribution of pathology in the brain allows the paediatric radiologist to develop a logical approach to the interpretation of MR imaging of these deep cerebellar nuclei. In this article we review the normal appearance and MR features of the dentate nuclei, including changes that are seen with myelination. We describe the specific imaging characteristics of childhood diseases that involve the dentate nuclei, and develop a systematic approach to the differential diagnosis of dentate nucleus abnormalities on MR imaging. (orig.)

The dentate nucleus in children: normal development and patterns of disease

International Nuclear Information System (INIS)

McErlean, Aoife; Abdalla, Khaled; Donoghue, Veronica; Ryan, Stephanie

2010-01-01

The dentate nuclei lie deep within the cerebellum and play a vital role in the pathways involved in fine motor control and coordination. They are susceptible to a variety of diseases. Some pathological processes preferentially affect the dentate nuclei, while concomitant basal ganglia or white matter involvement can be a striking finding in others. A familiarity with the normal appearance of the dentate nuclei at different ages in combination with the radiological distribution of pathology in the brain allows the paediatric radiologist to develop a logical approach to the interpretation of MR imaging of these deep cerebellar nuclei. In this article we review the normal appearance and MR features of the dentate nuclei, including changes that are seen with myelination. We describe the specific imaging characteristics of childhood diseases that involve the dentate nuclei, and develop a systematic approach to the differential diagnosis of dentate nucleus abnormalities on MR imaging. (orig.)

Transplantation Dose Alters the Differentiation Program of Hematopoietic Stem Cells.

Science.gov (United States)

Brewer, Casey; Chu, Elizabeth; Chin, Mike; Lu, Rong

2016-05-24

Hematopoietic stem cell (HSC) transplantation is the most prevalent stem cell therapy, but it remains a risky procedure. To improve this treatment, it is important to understand how transplanted stem cells rebuild the blood and immune systems and how this process is impacted by transplantation variables such as the HSC dose. Here, we find that, in the long term following transplantation, 70%-80% of donor-HSC-derived clones do not produce all measured blood cell types. High HSC doses lead to more clones that exhibit balanced lymphocyte production, whereas low doses produce more T-cell-specialized clones. High HSC doses also produce significantly higher proportions of early-differentiating clones compared to low doses. These complex differentiation behaviors uncover the clonal-level regeneration dynamics of hematopoietic regeneration and suggest that transplantation dose can be exploited to improve stem cell therapy. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Correlations in hadron-nucleus collisions

International Nuclear Information System (INIS)

Wosiek, B.

1976-09-01

The correlations between the particles produced in interactions of hadrons with emulsion nuclei were investigated. The data are in qualitative agreement with the models which describe the interactions with nuclei as subsequent collisions of the fast part of excited hadronic matter inside the nucleus. (author)

External incentives and internal states guide goal-directed behavior via the differential recruitment of the nucleus accumbens and the medial prefrontal cortex.

Science.gov (United States)

Moscarello, J M; Ben-Shahar, O; Ettenberg, A

2010-10-13

Goal-directed behavior is governed by internal physiological states and external incentives present in the environment (e.g. hunger and food). While the role of the mesocorticolimbic dopamine (DA) system in behavior guided by environmental incentives has been well studied, the effect of relevant physiological states on the function of this system is less understood. The current study examined the role of the medial prefrontal cortex (mPFC) and the nucleus accumbens (NAcc) in the kind of food-reinforced behaviors known to be sensitive to the internal state produced by food deprivation conditions. Operant lever-press reinforced on fixed ratio 1 (FR1) and progressive ratio (PR) schedules was tested after temporary inactivation of, or DA receptor blockade in, the prelimbic mPFC or NAcc core of rats with differing levels of food deprivation (0, 12 and 36-h). Food deprivation increased PR breakpoints, as well as the number of lever-presses emitted on the FR1 schedule. Both temporary inactivation and DA blockade of NAcc reduced breakpoints across deprivation conditions, while temporary inactivation and DA blockade of mPFC reduced breakpoints only in food-deprived rats. Neither manipulation of mPFC and NAcc had any effect on behavior reinforced on the FR1 schedule. Thus, mPFC and NAcc were differentially relevant to the behaviors tested-NAcc was recruited when the behavioral cost per reinforcer was rising or high regardless of food deprivation conditions, while mPFC was recruited when food-deprived animals behaved through periods of sparse reinforcement density in order to maximize available gain. Copyright 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

Production of Λc+ hypernuclei in antiproton–nucleus collisions

Directory of Open Access Journals (Sweden)

R. Shyam

2017-07-01

Full Text Available We investigate the production of charm-baryon hypernucleus OΛc+16 in the antiproton–O16 collisions within a fully covariant model that is based on an effective Lagrangian approach. The explicit Λ¯c−Λc+ production vertex is described by the t-channel D0 and D⁎0 meson-exchanges in the initial collision of the incident antiproton with one of the protons of the target nucleus. The Λc+ bound state spinors as well as the self-energies of the exchanged mesons employed in our calculations are derived from the quark–meson coupling model. The parameters of various vertices are taken to be the same as those used in our previous study of the elementary p¯+p→Λ¯c−+Λc+ reaction. We find that for antiproton beam momenta of interest to the P¯ANDA experiment, the 0∘ differential cross sections for the formation of OΛc+16 hypernuclear states with simple particle–hole configurations, have magnitudes in the range of a few μb/sr.

The nucleus is an intracellular propagator of tensile forces in NIH 3T3 fibroblasts

Science.gov (United States)

Alam, Samer G.; Lovett, David; Kim, Dae In; Roux, Kyle J.; Dickinson, Richard B.; Lele, Tanmay P.

2015-01-01

ABSTRACT Nuclear positioning is a crucial cell function, but how a migrating cell positions its nucleus is not understood. Using traction-force microscopy, we found that the position of the nucleus in migrating fibroblasts closely coincided with the center point of the traction-force balance, called the point of maximum tension (PMT). Positioning of the nucleus close to the PMT required nucleus–cytoskeleton connections through linker of nucleoskeleton-to-cytoskeleton (LINC) complexes. Although the nucleus briefly lagged behind the PMT following spontaneous detachment of the uropod during migration, the nucleus quickly repositioned to the PMT within a few minutes. Moreover, traction-generating spontaneous protrusions deformed the nearby nucleus surface to pull the nuclear centroid toward the new PMT, and subsequent retraction of these protrusions relaxed the nuclear deformation and restored the nucleus to its original position. We propose that the protruding or retracting cell boundary transmits a force to the surface of the nucleus through the intervening cytoskeletal network connected by the LINC complexes, and that these forces help to position the nucleus centrally and allow the nucleus to efficiently propagate traction forces across the length of the cell during migration. PMID:25908852

On angular distribution of nucleus fission fragments by fast neutrons

International Nuclear Information System (INIS)

Barabanov, A.L.; Grechukhin, D.P.

1987-01-01

Evaluation of amplitudes of quadrupole and hexadecapole components of angular distribution of nucleus fission fragments by neutrons with the energies E n < or approx. 6 MeV is conducted. Stability of this amplitude to permeability optical coefficient variations for neutrons is revealed. It is shown, that the ratio of these amplitudes as well as the character of their dependence on the target nucleus orientation degree are sensitive to the type of fission probability distribution along K projection if fissile nucleus J spin to the fragment scattering axis. This sensitivity may be used for fragment angular distribution anisotropy formation statistical model verification

Fear and Reward Circuit Alterations in Pediatric CRPS.

Science.gov (United States)

Simons, Laura E; Erpelding, Nathalie; Hernandez, Jessica M; Serrano, Paul; Zhang, Kunyu; Lebel, Alyssa A; Sethna, Navil F; Berde, Charles B; Prabhu, Sanjay P; Becerra, Lino; Borsook, David

2015-01-01

In chronic pain, a number of brain regions involved in emotion (e.g., amygdala, hippocampus, nucleus accumbens, insula, anterior cingulate, and prefrontal cortex) show significant functional and morphometric changes. One phenotypic manifestation of these changes is pain-related fear (PRF). PRF is associated with profoundly altered behavioral adaptations to chronic pain. For example, patients with a neuropathic pain condition known as complex regional pain syndrome (CRPS) often avoid use of and may even neglect the affected body area(s), thus maintaining and likely enhancing PRF. These changes form part of an overall maladaptation to chronic pain. To examine fear-related brain circuit alterations in humans, 20 pediatric patients with CRPS and 20 sex- and age-matched healthy controls underwent functional magnetic resonance imaging (fMRI) in response to a well-established fearful faces paradigm. Despite no significant differences on self-reported emotional valence and arousal between the two groups, CRPS patients displayed a diminished response to fearful faces in regions associated with emotional processing compared to healthy controls. Additionally, increased PRF levels were associated with decreased activity in a number of brain regions including the right amygdala, insula, putamen, and caudate. Blunted activation in patients suggests that (a) individuals with chronic pain may have deficits in cognitive-affective brain circuits that may represent an underlying vulnerability or consequence to the chronic pain state; and (b) fear of pain may contribute and/or maintain these brain alterations. Our results shed new light on altered affective circuits in patients with chronic pain and identify PRF as a potentially important treatment target.

Duodenal and ileal glucose infusions differentially alter gastrointestinal peptides, appetite response, and food intake: a tube feeding study.

Science.gov (United States)

Poppitt, Sally D; Shin, Hyun Sang; McGill, Anne-Thea; Budgett, Stephanie C; Lo, Kim; Pahl, Malcolm; Duxfield, Janice; Lane, Mark; Ingram, John R

2017-09-01

Background: Activation of the ileal brake through the delivery of nutrients into the distal small intestine to promote satiety and suppress food intake provides a new target for weight loss. Evidence is limited, with support from naso-ileal lipid infusion studies. Objective: The objective of the study was to investigate whether glucose infused into the duodenum and ileum differentially alters appetite response, food intake, and secretion of satiety-related gastrointestinal peptides. Design: Fourteen healthy male participants were randomly assigned to a blinded 4-treatment crossover, with each treatment of single-day duration. On the day before the intervention (day 0), a 380-cm multilumen tube (1.75-mm diameter) with independent port access to the duodenum and ileum was inserted, and position was confirmed by X-ray. Subsequently (days 1-4), a standardized breakfast meal was followed midmorning by a 90-min infusion of isotonic glucose (15 g, 235 kJ) or saline to the duodenum or ileum. Appetite ratings were assessed with the use of visual analog scales (VASs), blood samples collected, and ad libitum energy intake (EI) measured at lunch, afternoon snack, and dinner. Results: Thirteen participants completed the 4 infusion days. There was a significant effect of nutrient infused and site (treatment × time, P appetite, and decreased ad libitum EI at a subsequent meal. Although glucose to the duodenum also suppressed appetite ratings, eating behavior was not altered. This trial was registered at www.anzctr.org.au as ACTRN12612000429853. © 2017 American Society for Nutrition.

Supersensitive Kappa Opioid Receptors Promotes Ethanol Withdrawal-Related Behaviors and Reduce Dopamine Signaling in the Nucleus Accumbens.

Science.gov (United States)

Rose, Jamie H; Karkhanis, Anushree N; Chen, Rong; Gioia, Dominic; Lopez, Marcelo F; Becker, Howard C; McCool, Brian A; Jones, Sara R

2016-05-01

Chronic ethanol exposure reduces dopamine transmission in the nucleus accumbens, which may contribute to the negative affective symptoms associated with ethanol withdrawal. Kappa opioid receptors have been implicated in withdrawal-induced excessive drinking and anxiety-like behaviors and are known to inhibit dopamine release in the nucleus accumbens. The effects of chronic ethanol exposure on kappa opioid receptor-mediated changes in dopamine transmission at the level of the dopamine terminal and withdrawal-related behaviors were examined. Five weeks of chronic intermittent ethanol exposure in male C57BL/6 mice were used to examine the role of kappa opioid receptors in chronic ethanol-induced increases in ethanol intake and marble burying, a measure of anxiety/compulsive-like behavior. Drinking and marble burying were evaluated before and after chronic intermittent ethanol exposure, with and without kappa opioid receptor blockade by nor-binaltorphimine (10mg/kg i.p.). Functional alterations in kappa opioid receptors were assessed using fast scan cyclic voltammetry in brain slices containing the nucleus accumbens. Chronic intermittent ethanol-exposed mice showed increased ethanol drinking and marble burying compared with controls, which was attenuated with kappa opioid receptor blockade. Chronic intermittent ethanol-induced increases in behavior were replicated with kappa opioid receptor activation in naïve mice. Fast scan cyclic voltammetry revealed that chronic intermittent ethanol reduced accumbal dopamine release and increased uptake rates, promoting a hypodopaminergic state of this region. Kappa opioid receptor activation with U50,488H concentration-dependently decreased dopamine release in both groups; however, this effect was greater in chronic intermittent ethanol-treated mice, indicating kappa opioid receptor supersensitivity in this group. These data suggest that the chronic intermittent ethanol-induced increase in ethanol intake and anxiety

A comparative analysis of mechanisms of fast light particles production in nucleus-nucleus collisions at low and intermediate energies

CERN Document Server

Denikin, A S

2002-01-01

The dynamics and the mechanisms of formation of pre-equilibrium light particles in nucleus-nucleus collisions at low and intermediate energies are discussed in terms of a classical four-body model. The energy and angular distributions of light particles have been calculated. It has been found that at energies lower than 50A MeV the formation of the most high-energy part of the nuclear spectrum occurs at the expense of the acceleration of light target particles with the mean field of the projectile. The obtained data are in good agreement with available experimental data

Deconvolving the Nucleus of Centaurus A Using Chandra PSF Library

Science.gov (United States)

Karovska, Margarita

2000-01-01

Centaurus A (NGC 5128) is a giant early-type galaxy containing the nearest (at 3.5 Mpc) radio-bright Active Galactic Nucleus (AGN). Cen A was observed with the High Resolution Camera (HRC) on the Chandra X-ray Observatory on several occasions since the launch in July 1999. The high-angular resolution (less than 0.5 arcsecond) Chandra/HRC images reveal X ray multi-scale structures in this object with unprecedented detail and clarity, including the bright nucleus believed to be associated with a supermassive black hole. We explored the spatial extent of the Cen A nucleus using deconvolution techniques on the full resolution Chandra images. Model point spread functions (PSFs) were derived from the standard Chandra raytrace PSF library as well as unresolved point sources observed with Chandra. The deconvolved images show that the Cen A nucleus is resolved and asymmetric. We discuss several possible causes of this extended emission and of the asymmetries.

WISE/NEOWISE PRELIMINARY ANALYSIS AND HIGHLIGHTS OF THE 67P/CHURYUMOV-GERASIMENKO NEAR NUCLEUS ENVIRONS

Energy Technology Data Exchange (ETDEWEB)

Bauer, James M.; Kramer, Emily; Mainzer, A. K.; Stevenson, Rachel; Masiero, Joseph R.; Weissman, Paul R. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, MS 183-401, Pasadena, CA 91109 (United States); Grav, Tommy [Planetary Science Institute, 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719-2395 (United States); Walker, Russell G. [Monterey Institute for Research in Astronomy, 200 Eighth Street, Marina, CA 93933 (United States); Fernandez, Yan R. [Department of Physics, University of Central Florida, 4000 Central Florida Boulevard, P.S. Building, Orlando, FL 32816-2385 (United States); Meech, Karen J. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Manoa, HI 96822 (United States); Lisse, Carey M. [Applied Physics Laboratory, Johns Hopkins University, 11100 Johns Hopkins Road, Laurel, MD 20723-6099 (United States); Cutri, Roc M.; Dailey, John W.; Masci, Frank J.; Pearman, George [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Tholen, David J. [NASA Astrobiology Institute, University of Hawaii, Manoa, HI 96822 (United States); Wright, Edward L., E-mail: bauer@scn.jpl.nasa.gov [Department of Physics and Astronomy, University of California, P.O. Box 91547, Los Angeles, CA 90095-1547 (United States); Collaboration: WISE Team

2012-10-10

On 2010 January 18-19 and June 28-29, the Wide-field Infrared Survey Explorer (WISE) spacecraft imaged the Rosetta mission target, comet 67P/Churyumov-Gerasimenko. We present a preliminary analysis of the images, which provide a characterization of the dust environment at heliocentric distances similar to those planned for the initial spacecraft encounter, but on the outbound leg of its orbit rather than the inbound. Broadband photometry yields low levels of CO{sub 2} production at a comet heliocentric distance of 3.32 AU and no detectable production at 4.18 AU. We find that at these heliocentric distances, large dust grains with mean grain diameters on the order of a millimeter or greater dominate the coma and evolve to populate the tail. This is further supported by broadband photometry centered on the nucleus, which yield an estimated differential dust particle size distribution with a power-law relation that is considerably shallower than average. We set a 3{sigma} upper limit constraint on the albedo of the large-grain dust at {<=}0.12. Our best estimate of the nucleus radius (1.82 {+-} 0.20 km) and albedo (0.04 {+-} 0.01) are in agreement with measurements previously reported in the literature.

Standard and Nonstandard Neutrino-Nucleus Reactions Cross Sections and Event Rates to Neutrino Detection Experiments

Directory of Open Access Journals (Sweden)

D. K. Papoulias

2015-01-01

Full Text Available In this work, we explore ν-nucleus processes from a nuclear theory point of view and obtain results with high confidence level based on accurate nuclear structure cross sections calculations. Besides cross sections, the present study includes simulated signals expected to be recorded by nuclear detectors and differential event rates as well as total number of events predicted to be measured. Our original cross sections calculations are focused on measurable rates for the standard model process, but we also perform calculations for various channels of the nonstandard neutrino-nucleus reactions and come out with promising results within the current upper limits of the corresponding exotic parameters. We concentrate on the possibility of detecting (i supernova neutrinos by using massive detectors like those of the GERDA and SuperCDMS dark matter experiments and (ii laboratory neutrinos produced near the spallation neutron source facilities (at Oak Ridge National Lab by the COHERENT experiment. Our nuclear calculations take advantage of the relevant experimental sensitivity and employ the severe bounds extracted for the exotic parameters entering the Lagrangians of various particle physics models and specifically those resulting from the charged lepton flavour violating μ-→e- experiments (Mu2e and COMET experiments.

Interaction between hypothalamic dorsomedial nucleus and the suprachiasmatic nucleus determines intensity of food anticipatory behavior

NARCIS (Netherlands)

Acosta-Galvan, Guadalupe; Yi, Chun-Xia; van der Vliet, Jan; Jhamandas, Jack H.; Panula, Pertti; Angeles-Castellanos, Manuel; del Carmen Basualdo, María; Escobar, Carolina; Buijs, Ruud M.

2011-01-01

Food anticipatory behavior (FAA) is induced by limiting access to food for a few hours daily. Animals anticipate this scheduled meal event even without the suprachiasmatic nucleus (SCN), the biological clock. Consequently, a food-entrained oscillator has been proposed to be responsible for meal time

HIJET: a Monte Carlo event generator for P-nucleus-nucleus collisions

International Nuclear Information System (INIS)

Ludlam, T.; Pfoh, A.; Shor, A.

1985-01-01

Comparisons are shown for the HIJET generated data and measured data for average multiplicities, rapidity distributions, and leading proton spectra in proton-nucleus and heavy ion reactions. The algorithm for the generator is one of an incident particle on a target of uniformly distributed nucleons. The dynamics of the interaction limit secondary interactions in that only the leading baryon may re-interact with the nuclear volume. Energy and four momentum are globally conserved in each event. 6 refs., 6 figs

Cilostazol induces C-fos expression in the trigeminal nucleus caudalis and behavioural changes suggestive of headache with the migraine-like feature photophobia in female rats

DEFF Research Database (Denmark)

Christensen, S L; Petersen, Steffen; Sørensen, Dorte B

2018-01-01

-like behaviours and c-fos expression in rats. In order to evaluate the predictive validity of the model, we examined the response to the migraine specific drug sumatriptan. Methods The effect of cilostazol (125 mg/kg p.o.) in female Sprague Dawley rats was evaluated on a range of spontaneous behavioural...... parameters, light sensitivity and mechanical sensitivity thresholds. We also measured c-fos expression in the trigeminal nucleus caudalis. Results Cilostazol increased light sensitivity and grooming behaviour. These manifestations were not inhibited by sumatriptan. Cilostazol also induced c-fos expression...... in the trigeminal nucleus caudalis. Furthermore, trigeminal - but not hind paw hyperalgesia was observed. Conclusion The altered behaviours are suggestive of cilostazol induced headache with migraine-like features, but not specific. The presence of head specific hyperalgesia and the c-fos response in the trigeminal...

Final State Interactions Effects in Neutrino-Nucleus Interactions

Energy Technology Data Exchange (ETDEWEB)

Golan, Tomasz [Univ. of Wroctaw (Poland); Juszczak, Cezary [Univ. of Wroctaw (Poland); Sobczyk, Jan T. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)

2012-07-01

Final State Interactions effects are discussed in the context of Monte Carlo simulations of neutrino-nucleus interactions. A role of Formation Time is explained and several models describing this effect are compared. Various observables which are sensitive to FSI effects are reviewed including pion-nucleus interaction and hadron yields in backward hemisphere. NuWro Monte Carlo neutrino event generator is described and its ability to understand neutral current $\\pi^0$ production data in $\\sim 1$ GeV neutrino flux experiments is demonstrated.

Comet Halley: nucleus and jets

International Nuclear Information System (INIS)

Sagdeev, R.Z.; Avanesov, G.A.; Barinov, I.V.

1986-06-01

The VEGA-1 and VEGA-2 spacecrafts made their closest approach to Comet Halley on 6 and 9 March, respectively. In this paper results of the onboard imaging experiment are discussed. The nucleus of the comet was clearly identifyable as an irregularly shaped object with overall dimensions of (16+-1)x(8+-1)x(8+-1) km. The nucleus rotates around its axis which is nearly perpendicular to the orbital plane, with a period of 53+-2 hours. Its albedo is only 0.04+-002. Most of the jet features observed during the second fly-by were spatially reconstructed. These sources form a quasi-linear structure on the surface. The dust above the surface is shown to be optically thin except certain specific dust jets. Brightness features on the surface are clearly seen. Correlating the data with other measurements it is concluded that the dirty snow-ball model probably has to be revised. (author)

Ketogenic diet alters dopaminergic activity in the mouse cortex.

Science.gov (United States)

Church, William H; Adams, Ryan E; Wyss, Livia S

2014-06-13

The present study was conducted to determine if the ketogenic diet altered basal levels of monoamine neurotransmitters in mice. The catecholamines dopamine (DA) and norephinephrine (NE) and the indolamine serotonin (5HT) were quantified postmortem in six different brain regions of adult mice fed a ketogenic diet for 3 weeks. The dopamine metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) and the serotonin metabolite 5-hydroxyindole acetic acid (5HIAA) were also measured. Tissue punches were collected bilaterally from the motor cortex, somatosensory cortex, nucleus accumbens, anterior caudate-putamen, posterior caudate-putamen and the midbrain. Dopaminergic activity, as measured by the dopamine metabolites to dopamine content ratio - ([DOPAC]+[HVA])/[DA] - was significantly increased in the motor and somatosensory cortex regions of mice fed the ketogenic diet when compared to those same areas in brains of mice fed a normal diet. These results indicate that the ketogenic diet alters the activity of the meso-cortical dopaminergic system, which may contribute to the diet's therapeutic effect in reducing epileptic seizure activity. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Gross and Fine Structure of Pion Production Excitation Functions in {bold {ital p}}-Nucleus and Nucleus-Nucleus Reactions

Energy Technology Data Exchange (ETDEWEB)

Jakobsson, B.; Berg, M.; Carlen, L.; Elmer, R.; Fokin, A.; Ghetti, R.; Martensson, J.; Noren, B.; Oskarsson, A.; Whitlow, H.J. [Department of Physics, University of Lund, Lund (Sweden); Ekstroem, C.; Ericsson, G.; Romanski, J.; van Veldhuizen, E.J.; Westerberg, L. [The Svedberg Laboratory and Department of Neutron Physics, University of Uppsala, Uppsala (Sweden); Julien, J. [Centre d`Etudes Nucleaires, Saclay (France); Skeppstedt, O. [Department of Physics, Chalmers Institute of Technology, Gothenburg (Sweden); Nyboe, K.; Thorsteinsen, T.F.; Amirelmi, S. [Department of Physics, University of Bergen, Bergen (Norway); Guttormsen, M.; Lo/vho/iden, G. [Department of Physics, University of Oslo, Oslo (Norway); Bellini, V.; Palazzolo, F.; Sperduto, M.L. [Istituto Nazionale di Fisica Nucleare/Laboratorio Nazionale del Sud, University of Catania, Catania (Italy); Bondorf, J.P.; Mishustin, I. [Niels Bohr Institute, Copenhagen (Denmark); Avdeichikov, V. [Joint Institute for Nuclear Research, Dubna (Russia); Lozhkin, O.V.; Murin, Y. [V.G. Khlopin Radium Institute, St.Petersburg (Russia)

1997-05-01

Slow ramping of the CELSIUS storage ring has been utilized to measure the yield of charged pions in proton and heavy ion induced collisions with continuously varying beam energy. Boltzmann-Uehling-Uhlenbeck predictions, including Fermi momenta of nucleons in nuclei, follow the general shape of the p-nucleus excitation functions quite well except for a general overestimation of the backward emission. For heavy ion reactions the calculated yield also falls off faster with decreasing beam energy than the data. No statistically significant narrow resonances are observed. {copyright} {ital 1997} {ital The American Physical Society}

Models of the atomic nucleus. With interactive software

International Nuclear Information System (INIS)

Cook, N.D.

2006-01-01

This book-and-CD-software package supplies users with an interactive experience for nuclear visualization via a computer-graphical interface, similar in principle to the molecular visualizations already available in chemistry. Models of the Atomic Nucleus, a largely non-technical introduction to nuclear theory, explains the nucleus in a way that makes nuclear physics as comprehensible as chemistry or cell biology. The book/software supplements virtually any of the current textbooks in nuclear physics by providing a means for 3D visual display of the diverse models of nuclear structure. For the first time, an easy-to-master software for scientific visualization of the nucleus makes this notoriously ''non-visual'' field become immediately 'visible.' After a review of the basics, the book explores and compares the competing models, and addresses how the lattice model best resolves remaining controversies. The appendix explains how to obtain the most from the software provided on the accompanying CD. (orig.)

Ancestral vinclozolin exposure alters the epigenetic transgenerational inheritance of sperm small noncoding RNAs.

Science.gov (United States)

Schuster, Andrew; Skinner, Michael K; Yan, Wei

Exposure to the agricultural fungicide vinclozolin during gestation promotes a higher incidence of various diseases in the subsequent unexposed F3 and F4 generations. This phenomenon is termed epigenetic transgenerational inheritance and has been shown to in part involve alterations in DNA methylation, but the role of other epigenetic mechanisms remains unknown. The current study investigated the alterations in small noncoding RNA (sncRNA) in the sperm from F3 generation control and vinclozolin lineage rats. Over 200 differentially expressed sncRNAs were identified and the tRNA-derived sncRNAs, namely 5' halves of mature tRNAs (5' halves), displayed the most dramatic changes. Gene targets of the altered miRNAs and tRNA 5' halves revealed associations between the altered sncRNAs and differentially DNA methylated regions. Dysregulated sncRNAs appear to correlate with mRNA profiles associated with the previously observed vinclozolin-induced disease phenotypes. Data suggest potential connections between sperm-borne RNAs and the vinclozolin-induced epigenetic transgenerational inheritance phenomenon.

Immobility, inheritance and plasticity of shape of the yeast nucleus

Directory of Open Access Journals (Sweden)

Andrulis Erik D

2007-11-01

Full Text Available Abstract Background Since S. cerevisiae undergoes closed mitosis, the nuclear envelope of the daughter nucleus is continuous with that of the maternal nucleus at anaphase. Nevertheless, several constitutents of the maternal nucleus are not present in the daughter nucleus. The present study aims to identify proteins which impact the shape of the yeast nucleus and to learn whether modifications of shape are passed on to the next mitotic generation. The Esc1p protein of S. cerevisiae localizes to the periphery of the nucleoplasm, can anchor chromatin, and has been implicated in targeted silencing both at telomeres and at HMR. Results Upon increased Esc1p expression, cell division continues and dramatic elaborations of the nuclear envelope extend into the cytoplasm. These "escapades" include nuclear pores and associate with the nucleolus, but exclude chromatin. Escapades are not inherited by daughter nuclei. This exclusion reflects their relative immobility, which we document in studies of prezygotes. Moreover, excess Esc1p affects the levels of multiple transcripts, not all of which originate at telomere-proximal loci. Unlike Esc1p and the colocalizing protein, Mlp1p, overexpression of selected proteins of the inner nuclear membrane is toxic. Conclusion Esc1p is the first non-membrane protein of the nuclear periphery which – like proteins of the nuclear lamina of higher eukaryotes – can modify the shape of the yeast nucleus. The elaborations of the nuclear envelope ("escapades" which appear upon induction of excess Esc1p are not inherited during mitotic growth. The lack of inheritance of such components could help sustain cell growth when parental nuclei have acquired potentially deleterious characteristics.

WIMP-nucleus scattering in chiral effective theory

Science.gov (United States)

Cirigliano, Vincenzo; Graesser, Michael L.; Ovanesyan, Grigory

2012-10-01

We discuss long-distance QCD corrections to the WIMP-nucleon(s) interactions in the framework of chiral effective theory. For scalar-mediated WIMP-quark interactions, we calculate all the next-to-leading-order corrections to the WIMP-nucleus elastic cross-section, including two-nucleon amplitudes and recoil-energy dependent shifts to the single-nucleon scalar form factors. As a consequence, the scalar-mediated WIMP-nucleus cross-section cannot be parameterized in terms of just two quantities, namely the neutron and proton scalar form factors at zero momentum transfer, but additional parameters appear, depending on the short-distance WIMP-quark interaction. Moreover, multiplicative factorization of the cross-section into particle, nuclear and astro-particle parts is violated. In practice, while the new effects are of the natural size expected by chiral power counting, they become very important in those regions of parameter space where the leading order WIMP-nucleus amplitude is suppressed, including the so-called "isospin-violating dark matter" regime. In these regions of parameter space we find order-of-magnitude corrections to the total scattering rates and qualitative changes to the shape of recoil spectra.

Proton decay in a nucleus: Nonrelativistic treatment of nuclear effects

International Nuclear Information System (INIS)

Fernandez, L.A.; Alvarez-Estrada, R.F.; Sanchez-Gomez, J.L.

1983-01-01

In this paper, proton decay in a large nucleus is studied in the framework of SU(5) grand unification theory (GUT). By using a method based upon the Green's-function technique of many-body physics, nuclear effects on spectator and pole terms are computed. The decay width in the nucleus is found to be practically the same as in free space. However, nuclear effects are of considerable importance concerning the positron spectrum. A density-correlation expansion is introduced which is useful for carrying out a systematic study of nuclear effects in proton decay in a large nucleus. The method presented here can be easily extended to other GUT's or supersymmetric GUT's

Non-compound nucleus fission in actinide and pre-actinide regions

Indian Academy of Sciences (India)

2015-07-22

Jul 22, 2015 ... In this article, some of our recent results on fission fragment/product angular distributions are discussed in the context of non-compound nucleus fission. Measurement of fission fragment angular distribution in 28Si+176Yb reaction did not show a large contribution from the non-compound nucleus fission.

Some preliminary considerations on antiproton-nucleus experiments

International Nuclear Information System (INIS)

Yavin, A.I.

1981-05-01

The antiproton as a probe of the atomic nucleus is discussed in the expectation that fairly intense beams of high quality will be available in 1983 at the Low Energy Antiproton Ring (LEAR) facility at CERN and possibly also in some other laboratories at a later date. Several antiproton-nucleus experiments are proposed, and the possibility of observing antiprotonic nuclei as well as antineutronic nuclei is discussed. It is demonstrated that even for the study of the elementary nucleon-antinucleon systems it could be advantageous to use nuclei rather than protons as target. The possibility of investigating several antiprotonic atomic systems is also briefly discussed [fr

Cell Nucleus-Targeting Zwitterionic Carbon Dots.

Science.gov (United States)

Jung, Yun Kyung; Shin, Eeseul; Kim, Byeong-Su

2015-12-22

An innovative nucleus-targeting zwitterionic carbon dot (CD) vehicle has been developed for anticancer drug delivery and optical monitoring. The zwitterionic functional groups of the CDs introduced by a simple one-step synthesis using β-alanine as a passivating and zwitterionic ligand allow cytoplasmic uptake and subsequent nuclear translocation of the CDs. Moreover, multicolor fluorescence improves the accuracy of the CDs as an optical code. The CD-based drug delivery system constructed by non-covalent grafting of doxorubicin, exhibits superior antitumor efficacy owing to enhanced nuclear delivery in vitro and tumor accumulation in vivo, resulting in highly effective tumor growth inhibition. Since the zwitterionic CDs are highly biocompatible and effectively translocated into the nucleus, it provides a compelling solution to a multifunctional nanoparticle for substantially enhanced nuclear uptake of drugs and optical monitoring of translocation.

Nucleus spectroscopy: extreme masses and deformations

International Nuclear Information System (INIS)

Theisen, Ch.

2009-12-01

The author proposes a synthesis of research activities performed since 1995 in the field of experimental nuclear physics, and more particularly in the investigation of two nucleus extreme states: deformation on the one hand, heavy and very heavy nuclei on the other hand. After a presentation of the context of investigations on deformation, rotation, and heavy nuclei, he gives an overview of developments regarding instruments (gamma spectrometers, detection of fission fragments, and detection at the focal plane of spectrometers or separators) and analysis techniques. Experiments and results are then reported and discussed, concerning super-deformed states with a high angular moment, spectroscopy of neutron-rich nuclei, very heavy nuclei close to nucleus map borders. He finally draws perspectives for middle and long term studies on the heaviest nuclei

Special role of neutron-halo nucleus on the momentum dissipation in heavy ion collisions

International Nuclear Information System (INIS)

Xing Yongzhong; Tianshui Normal Univ., Tianshui; Liu Jianye; Tianshui Normal Univ., Tianshui; Chinese Academy of Sciences, Lanzhou; Zuo Wei; Li Xiguo; Chinese Academy of Sciences, Lanzhou

2005-01-01

The special role of neutron-halo nucleus 19 B on the momentum dissipation was investigated by using isospin dependent quantum molecular dynamics. In order to compare and protrude the special role of neutron-halo-nucleus 19 B, the momentum dissipation induced by a same mass stable nucleus 19 F was investigated under the same incident channel condition. It is found that the weak bound neutron-halo structure of 19 B weakens the momentum dissipation process compared to those induced by stable nucleus 19 F in the lower energy region. However the nuclear stopping of colliding system with the neutron-halo nucleus 19 B decreases gradually with the increasing beam energy. For all of mass targets and impact parameters the neutron-halo nucleus 19 B weakens the momentum dissipation process. (authors)

Urocortin-1 within the centrally-projecting Edinger-Westphal nucleus is critical for ethanol preference.

Directory of Open Access Journals (Sweden)

William J Giardino

Full Text Available Converging lines of evidence point to the involvement of neurons of the centrally projecting Edinger-Westphal nucleus (EWcp containing the neuropeptide Urocortin-1 (Ucn1 in excessive ethanol (EtOH intake and EtOH sensitivity. Here, we expanded these previous findings by using a continuous-access, two-bottle choice drinking paradigm (3%, 6%, and 10% EtOH vs. tap water to compare EtOH intake and EtOH preference in Ucn1 genetic knockout (KO and wild-type (WT mice. Based on previous studies demonstrating that electrolytic lesion of the EWcp attenuated EtOH intake and preference in high-drinking C57BL/6J mice, we also set out to determine whether EWcp lesion would differentially alter EtOH consumption in Ucn1 KO and WT mice. Finally, we implemented well-established place conditioning procedures in KO and WT mice to determine whether Ucn1 and the corticotropin-releasing factor type-2 receptor (CRF-R2 were involved in the rewarding and aversive effects of EtOH (2 g/kg, i.p.. Results from these studies revealed that (1 genetic deletion of Ucn1 dampened EtOH preference only in mice with an intact EWcp, but not in mice that received lesion of the EWcp, (2 lesion of the EWcp dampened EtOH intake in Ucn1 KO and WT mice, but dampened EtOH preference only in WT mice expressing Ucn1, and (3 genetic deletion of Ucn1 or CRF-R2 abolished the conditioned rewarding effects of EtOH, but deletion of Ucn1 had no effect on the conditioned aversive effects of EtOH. The current findings provide strong support for the hypothesis that EWcp-Ucn1 neurons play an important role in EtOH intake, preference, and reward.

[Analysis of the Effect of Non-phacoemulsification Cataract Operation on Corneal Endothelial Cell Nucleus Division].

Science.gov (United States)

Huang, Zufeng; Miao, Xiaoqing

2015-09-01

To investigate the effect of non-phacoemulsification cataract operation in two different patterns of nucleus delivery on the quantity and morphology of corneal endothelial cells and postoperative visual acuity. Forty patients diagnosed with cataract underwent cataract surgery and were assigned into the direct nuclear delivery and semi-nuclear delivery groups. Lens density was measured and divided into the hard and soft lenses according to Emery-little lens nucleus grading system. Non-phacoemulsification cataract operation was performed. At 3 d after surgery, the quantity and morphology of corneal endothelium were counted and observed under corneal endothelial microscope. During 3-month postoperative follow-up, the endothelial cell loss rate, morphological changes and visual acuity were compared among four groups. Corneal endothelial cell loss rate in the direct delivery of hard nucleus group significantly differed from those in the other three groups before and 3 months after operation (P nucleus, semi-delivery of hard nucleus and semi-delivery soft nucleus groups (all P > 0.05). Preoperative and postoperative 2-d visual acuity did not differ between the semi-delivery of hard nucleus and direct delivery of soft nucleus groups (P = 0.49), significantly differed from those in the semi-delivery of soft nucleus (P = 0.03) and direct delivery of hard nucleus groups (P = 0.14). Visual acuity at postoperative four months did not differ among four groups (P = 0.067). During non-phacoemulsification cataract surgery, direct delivery of hard nucleus caused severe injury to corneal endothelium and semi-delivery of soft nucleus yielded mild corneal endothelial injury. Slight corneal endothelial injury exerted no apparent effect upon visual acuity and corneal endothelial morphology at three months after surgery.

Integrated analysis of HPV-mediated immune alterations in cervical cancer.

Science.gov (United States)

Chen, Long; Luan, Shaohong; Xia, Baoguo; Liu, Yansheng; Gao, Yuan; Yu, Hongyan; Mu, Qingling; Zhang, Ping; Zhang, Weina; Zhang, Shengmiao; Wei, Guopeng; Yang, Min; Li, Ke

2018-05-01

Human papillomavirus (HPV) infection is the primary cause of cervical cancer. HPV-mediated immune alterations are known to play crucial roles in determining viral persistence and host cell transformation. We sought to thoroughly understand HPV-directed immune alterations in cervical cancer by exploring publically available datasets. 130 HPV positive and 7 HPV negative cervical cancer cases from The Cancer Genome Atlas were compared for differences in gene expression levels and functional enrichment. Analyses for copy number variation (CNV) and genetic mutation were conducted for differentially expressed immune genes. Kaplan-Meier analysis was performed to assess survival and relapse differences across cases with or without alterations of the identified immune signature genes. Genes up-regulated in HPV positive cervical cancer were enriched for various gene ontology terms of immune processes (P=1.05E-14~1.00E-05). Integrated analysis of the differentially expressed immune genes identified 9 genes that displayed either CNV, genetic mutation and/or gene expression changes in at least 10% of the cases of HPV positive cervical cancer. Genomic amplification may cause elevated levels of these genes in some HPV positive cases. Finally, patients with alterations in at least one of the nine signature genes overall had earlier relapse compared to those without any alterations. The altered expression of either TFRC or MMP13 may indicate poor survival for a subset of cervical cancer patients (P=1.07E-07). We identified a novel immune gene signature for HPV positive cervical cancer that is potentially associated with early relapse of cervical cancer. Copyright © 2018. Published by Elsevier Inc.