bluuebunny/crossref_metadata_2025 huggingface dataset:
Ras-dva1 small GTPase regulates telencephalon development in Xenopus laevis embryos by controlling Fgf8 and Agr signaling at the anterior border of the neural plate
Authors: Tereshina Maria B. , Ermakova Galina V. , Ivanova Anastasiya S. , Zaraisky Andrey G.
Published: February 2014

We previously found that the small GTPase Ras-dva1 is essential for the telencephalic development in Xenopus laevis because Ras-dva1 controls the Fgf8-mediated induction of FoxG1 expression, a key telencephalic regulator. In this report, we show, however, that Ras-dva1 and FoxG1 are expressed in different groups of cells; whereas Ras-dva1 is expressed in the outer layer of the anterior neural fold, FoxG1 and Fgf8 are activated in the inner layer from which the telencephalon is derived. We resolve this paradox by demonstrating that Ras-dva1 is involved in the transduction of Fgf8 signal received by cells in the outer layer, which in turn send a feedback signal that stimulates FoxG1 expression in the inner layer. We show that this feedback signal is transmitted by secreted Agr proteins, the expression of which is activated in the outer layer by mediation of Ras-dva1 and the homeodomain transcription factor Otx2. In turn, Agrs are essential for maintaining Fgf8 and FoxG1 expression in cells at the anterior neural plate border. Our finding reveals a novel feedback loop mechanism based on the exchange of Fgf8 and Agr signaling between neural and non-neural compartments at the anterior margin of the neural plate and demonstrates a key role of Ras-dva1 in this mechanism.
Identification of an immune regulated phagosomal Rab cascade in macrophages
Authors: Pei Gang , Repnik Urska , Griffiths Gareth , Gutierrez Maximiliano Gabriel
Published: February 2014

Interferon-γ (IFN-γ) has been shown to regulate phagosome trafficking and function in macrophages but the molecular mechanisms involved are poorly understood. Here, we identify Rab20 as part of the machinery by which IFN-γ controls phagosome maturation. IFN-γ stimulated Rab20 association with early phagosomes in macrophages. Using single phagosome imaging in live cells, we found that Rab20 induced an early delay in phagosome maturation and extended the time Rab5a and phosphatidylinositol 3-phosphate (PI3P) remains associated with phagosomes. Moreover, Rab20 depletion in macrophages abrogated the phagosome maturation delay induced by IFN-γ. Finally, we demonstrate that Rab20 interacts with the Rab5 guanine nucleotide exchange factor Rabex-5 and that Rab20 knockdown impaired the IFN-γ-dependent Rabex-5/Rab5a recruitment into phagosomes. Altogether, we uncover here Rab20 as a key player in the Rab cascade by which IFN-γ induces a delay in phagosome maturation in macrophages.
Phosphorylation of the retinoic acid receptor RARγ2 is crucial for the neuronal differentiation of mouse embryonic stem cells
Authors: Al Tanoury Ziad , Gaouar Samia , Piskunov Aleksandr , Ye Tao , Urban Sylvia , Jost Bernard , Keime Céline , Davidson Irwin , Dierich Andrée , Rochette-Egly Cécile
Published: February 2014

Retinoic acid (RA) plays key roles in cell differentiation and growth arrest by activating nuclear receptors, RARs (α, β and γ), which are ligand dependent transcriptional factors. RARs are also phosphorylated in response to RA. Here we investigated the in vivo relevance of RARs phosphorylation during RA-induced neuronal differentiation of mouse embryonic stem (mES) cells. Using ES cells where the genes encoding each RAR subtype have been inactivated and stable rescue lines expressing RARs mutated in phosphor-acceptor sites, we show that RA-induced neuronal differentiation involves RARγ2 and requires RARγ2 phosphorylation. By gene expression profiling, we found that the phosphorylated form of RARγ2 regulates a small subset of genes through binding an unusual RA response element consisting of two direct repeats with a 7 base pair spacer. These new findings suggest an important role for RARγ phosphorylation during cell differentiation, and pave the way for further investigations during embryonic development.
Larval vision contributes to gregarious settlement in barnacles: adult red fluorescence as a possible visual signal
Authors: Matsumura Kiyotaka , Qian Pei-Yuan
Published: February 2014

Gregarious settlement, an essential behavior for many barnacle species that can only reproduce by mating with a nearby barnacle, has long been thought to rely on larval ability to recognize chemical signals from conspecifics during settlement. However, the cyprid, the settlement stage larva in barnacles, has one pair of compound eyes that appear only at the late nauplius VI and cyprid stages, but the function(s) of these eyes remains unknown. Here we show that cyprids of the intertidal barnacle Balanus (=Amphibalanus) amphitrite can locate adult barnacles even in the absence of chemical cues, and prefer to settle around them probably via larval sense of vision. We also show that the cyprids can discriminate color and preferred to settle on red surfaces. Moreover, we found that shells of adult B. amphitrite emit red auto-fluorescence and the adult extracts with the fluorescence as a visual signal attracted cyprid larvae to settle around it. We propose that the perception of specific visual signals can be involved in behavior of zooplankton including marine invertebrate larvae, and that barnacle auto-fluorescence may be a specific signal involved in gregarious larval settlement.
Chiral Incomplete-cubane-type MnIII3O4 Clusters Containing a µ3-Methoxido or Hydroxido
Authors: Inoue Marina , Suzuki Takayoshi , Sunatsuki Yukinari , Fuyuhiro Akira , Re Nazzareno
Published: February 2014

Two new cluster compounds having chiral incomplete-cubane-type MnIII3O4 cores were synthesized using (2S)-2-hydroxy-4-(salicylideneamino)butyrate (H2L−) and characterized by X-ray analysis as well as magnetic susceptibility and spectroscopic measurements. Compound 1 contains a [MnIII3(L)3(µ3-OMe)]− cluster anion, while compound 2 prepared in water has a heptanuclear structure bearing two [MnIII3(L)3(µ3-OH)]− clusters connected by a MnII(H2O)4 fragment. In both compounds, a moderate intracluster MnIII···MnIII ferromagnetic interaction was observed. It was also found that the MnIII3O4 cluster cores are maintained in solution.
Controlling the Rotation of Porphyrin Units in Ethynyl-linked Porphyrin Trimers for Dye-sensitized Solar Cells by Anchoring onto TiO2 Surface
Authors: Hamamura Tomofumi , Nakazaki Jotaro , Uchida Satoshi , Kubo Takaya , Segawa Hiroshi
Published: February 2014

An ethynyl-linked porphyrin trimer bearing carboxyphenyl anchoring groups at all the porphyrin units becomes planar upon adsorption onto TiO2, showing the Q band absorption and IPCE maximum at longer wavelengths.
Principles of Contract Law: Reflection in Labor Legislation
Authors: Filyushchenko Lyudmila
Published: February 2014

The article explores the reflection of the principles of contract law into a sphere of labour legislation, induced by intensification of private-law regulation. The features and a number of problems of application of the contract law principles (the freedom of contract, the obligation of execution, the invariability of contract terms, and the balance between private and public interest) are uncovered.
International Integration: Methodological Problems of Research
Authors: Rafalyuk Elena
Published: February 2014

The author investigates certain methodological problems of studying international integration. Complication of social relations and appearance of new integrated legislation branches testify to the necessity of using an interdisciplinary approach in the legal science. Such approach suggests taking into account the knowledge of various sciences in order to get an idea of the object under study and can be applied for studying international integration as a general scientific category. But modern legal studies should be based on an intersectoral method as well. Due to the development and deepening of integration processes a need arises in new methodological methods which allow investigating sets of norms, that promote the integration process (integration law). While studying international integration it is necessary to take into account the increasing convergence of private and public law, which means that as such it is necessary to use both private-law and public-law methodology.
Multi-Child Family and Problems of Its Social Welfare
Authors: Azarova YElyena
Published: February 2014

The article examines the concept of the multi-child family. It analyzes its special needs and requirements as well as demonstrates the financial insecurity of such families. The author reveals the role of families in the favorable demographic development of the country and examines the proposals of the experts, aimed at solving problems of large families.
International Law and Domestic Aspects of Russia´s Accession to the Civil Law Convention on Corruption
Authors: Morozov Andrey
Published: February 2014

The article is devoted to the study of international law and domestic issues of accession of the Russian Federation to the Civil Law Convention on Corruption. Analyzes the model of possible accession of Russia to the Convention. This article provides suggestions and recommendations for improving the implementation of the Convention under review in the Russian legal system.
Diasporas and Outsourcing: Evidence from oDesk and India
Authors: Ghani Ejaz , Kerr William R. , Stanton Christopher
Published: February 2014

We examine the role of the Indian diaspora in the outsourcing of work to India. Our data are taken from oDesk, the world's largest online platform for outsourced contracts. Despite oDesk minimizing many of the frictions that diaspora connections have traditionally overcome, diaspora connections still matter on oDesk, with ethnic Indians substantially more likely to choose a worker in India. This higher placement is the result of a greater likelihood of choosing India for the initial contract and substantial path dependence in location choices. We further examine wage and performance outcomes of outsourcing as a function of ethnic connections. Our examination of potential rationales for the greater ethnic-based placement of contracts assesses taste-based preferences and information differences.

This paper was accepted by Lee Fleming, entrepreneurship and innovation.
The Risk Preferences of U.S. Executives
Authors: Brenner Steffen
Published: February 2014

In this paper, I elicit risk attitudes of U.S. executives by calibrating a subjective option valuation model for option exercising data (1996 to 2008), yielding approximately 65,000 values of relative risk aversion (RRA) for almost 7,000 executives. The observed behavior is generally consistent with moderate risk aversion and a median (mean) RRA close to one (three). Values are validated for chief executive officers (CEOs) by testing theory-based predictions on the influence of individual characteristics on risk preferences such as gender, marital status, religiosity, and intelligence. Senior managers such as CEOs, presidents, and chairpersons of the boards of directors are significantly less risk averse than non-senior executives. RRA heterogeneity is strongly correlated with sector membership and firm-level variables such as size, performance, and capital structure. Alternative factors influencing option exercises are tested for their influence on RRA values.

This paper was accepted by Brad Barber, finance.
Universal Credit, ubiquitous conditionality and its implications for social citizenship
Authors: Dwyer Peter , Wright Sharon
Published: February 2014

Between 2013 and 2017 Universal Credit replaces six means-tested working age benefits. Backed by a punitive system of tiered sanctions and fines, Universal Credit represents a major expansion and intensification of personalised behavioural conditionality and indicates the ubiquity of conditionality at the heart of twenty-first century UK social citizenship.
Reference Interval Evaluation of High-Sensitivity Troponin T and N-Terminal B-Type Natriuretic Peptide in Vietnam and the US: The North South East West Trial
Authors: Gaggin Hanna K , Dang Phuoc V , Do Loi D , deFilippi Christopher R , Christenson Robert H , Lewandrowski Elizabeth L , Lewandrowski Kent B , Truong Binh Q , Pham Vinh Q , Vu Vu H , Vu Truong V , Nguyen Toan B , Belcher Arianna M , Femia Alexandra , Kelley Cynthia , Januzzi James L
Published: February 2014

BACKGROUND

Reference intervals of high-sensitivity troponin T (hs-cTnT) and N-terminal pro-B–type natriuretic peptide (NT-proBNP) have been determined from Western populations. No data are available regarding expected values in Asian populations.

METHODS

A total of 1157 age- and sex-matched healthy individuals (mean age, 41.2 years; 48.0% male) were prospectively enrolled from the US (n = 565) and Vietnam (n = 592). Blood samples were analyzed for hs-cTnT and NT-proBNP. Median values were determined for each country and compared in unadjusted analyses and in analyses adjusted for age, sex, body mass index, study site, race, and vital signs.

RESULTS

Median hs-cTnT concentrations were slightly higher for individuals from the US than for those from Vietnam, but both were below the limit of detection (3.7 vs 3.0 ng/L, respectively; P = 0.03). More US participants had an hs-cTnT concentration above the limit of detection (57.2% vs 47.3%; P = 0.001), but the 99th percentile concentration was slightly higher for Asians (US 15.1 vs Vietnam 19.0 ng/L). Concentrations for >98% of both populations were below the standard hs-cTnT 99th percentile of 14.0 ng/L (P = 0.54). Median NT-proBNP concentrations were slightly higher for US participants compared with Vietnamese participants (28 vs 16 ng/L, respectively; P < 0.001). Following adjustment, differences in concentrations of NT-proBNP between healthy US and Vietnamese populations remained significant, whereas for hs-cTnT the differences were no longer significant. Inclusion of hs-cTnT values down to the limit of blank did not change the result.

CONCLUSIONS

The differences in hs-cTnT and NT-proBNP between healthy individuals from the US and Vietnam are small. Previously derived reference intervals for both analytes may be applied in Asian populations.
Percepção parental do ambiente de residência e obesidade infantil no Distrito de Coimbra
Authors: Nogueira Helena , Ferrão Maria Miguel , Gama Augusta , Mourão Isabel , Marques Vítor Rosado , Padez Cristina
Published: February 2014

A obesidade é um dos maiores problemas de saúde pública da actualidade. Para além dos factores individuais, os lugares em que se vive podem influenciar o comportamento e a saúde, providenciando ou não oportunidades de desenvolver uma vida saudável. O objectivo deste estudo é analisar a associação entre a percepção parental do ambiente local e o excesso de peso e obesidade em 1885 crianças com idades entre os 3 e os 10 anos residentes no distrito de Coimbra. Os dados foram recolhidos entre Março e Julho de 2009, utilizando-se os intervalos definidos pela ITOF para classificar as crianças com excesso de peso e obesidade. As características ambientais foram avaliadas por inquérito (IPS). Efectuou-se uma Análise de Componentes Principais para Dados Categóricos, que conduziu à obtenção de duas dimensões ambientais, posteriormente usadas com variáveis independentes numa análise de regressão multinominal. Os resultados revelaram associações significativas entre as dimensões ambientais e o peso das crianças do sexo feminino. Este estudo tem implicações para a saúde e para as políticas sociais. Melhorar o ambiente físico e social comunitário, providenciando e mantendo lugares seguros para caminhar e passear (disponibilizando infra-estruturas de suporte a essas actividades, melhorando a organização e o controlo social) pode ser uma forma efectiva de modelar o peso das crianças e os seus níveis de saúde, actuais e futuros, sobretudo para o género feminino, grupo que se revela particularmente vulnerável ao ganho de peso.
Filhos, enteados e apadrinhados: discursos, políticas e práticas dos serviços de saúde da Diamang, Angola
Authors: Varanda Jorge
Published: February 2014

Este texto pretende revelar a complexidade da prestação de cuidados biomédicos na Companhia de Diamantes de Angola (Diamang). Intenta-se questionar as representações coloniais de equidade de tratamentos entre Brancos e Africanos por parte dos Serviços de Saúde da Diamang (SSD). A análise ilumina a prestação de cuidados biomédicos diferencial entre expatriados e africanos e como esta era replicada entre africanos. A hierarquia entre os africanos colocava os trabalhadores no topo, seguidos pelos seus familiares, sendo a pirâmide ocupada pela população sem relações com a produção de diamantes. Subjacentes aos discursos de igualdade de cuidados biomédicos havia também objectivos políticos internos e internacionais, que contribuíam para as reconceptualizações do Terceiro Império Português assim como para a (re)construção dos sujeitos africanos.
Ventos do mal: sopro da cura: cosmovisão, doença e cura entre os Felupes da Guiné-Bissau
Authors: Costa Luis Manuel Neves
Published: February 2014

Este artigo pretende fazer a abordagem da construção social da doença e suas dinâmicas entre os Felupes da Guiné-Bissau. Partindo do conhecimento da cosmovisão felupe pretende-se aceder ao entendimento das concepções sobre a doença, enquanto um mal social - produto de uma transgressão ou falta para com a ética de grupo -, suas representações, imagens, vivências, experiências e analisar os itinerários terapêuticos empreendidos, visando a resolução do mal e o restabelecer do equilíbrio. Nesta lógica, emerge uma pluralidade etiológica do mal, que determina uma pluralidade dos quadros nosológicos (em função dos sinais que alteram a ordem biológica), condicionando a demanda da resolução do mal junto dos amañen au (curandeiros) que presidem aos rituais nos locais de reparação/sacrifício (os altares sagrados, ukin) pedindo a intercepção de Deus (Emitay) ou do espírito respectivo (bakin). A investigação efectuada assentou na pesquisa etnográfica na aldeia de Suzana, a norte da Guiné-Bissau, entrevistando os diversos actores sociais (doentes, familiares e curandeiros).
Narrativas sobre a experiência da doença: desafios conceptuais e metodológicos
Authors: Nunes João Arriscado , Serra Rita , Barradas Carlos , Queirós Filipa
Published: February 2014

O presente artigo vem dar conta do processo conducente à adopção de uma estratégia metodológica que privilegia a narrativa pessoal sobre a doença no âmbito de um projecto de investigação em curso. Para o âmbito deste projecto, que se centra em três doenças (cancro, doenças respiratórias e obesidade infantil), as metodologias qualitativas foram consideradas as mais adequadas, quer pela riqueza de informação que incorporam, quer pela adequabilidade no que respeita aos objectivos e às hipóteses de trabalho delineadas. Privilegiou-se assim a utilização do MINI (McGill Illness Narrative Interview) (Groleau et al., 2006), uma ferramenta cuja utilização é apropriada ao campo que pretendemos estudar. Pretende-se portanto apresentar uma primeira abordagem às escolhas metodológicas e conceptuais tointerdisciplinamadas, bem como dar conta da importância das narrativas pessoais nos objectivos a que o projecto se propõe dar resposta.
Changes in stature of Portuguese women born between 1966 and 1982, according to educational level
Authors: Conceição Eunice , Garcia Susana , Padez Cristina , Cardoso Hugo
Published: February 2014

Studies which document secular change in stature are almost exclusively based on males, while similar data on females is less common. In addition, secular trends in socioeconomic differences of height are seldomly reported. This study aims to document changes in mean stature in a sample of Portuguese women born between 1966 and 1982 (n = 30,629). For this study self-reported stature data was obtained from a large sample of women who delivered their children at the Dr. Alfredo da Costa Maternity Hospital, in Lisbon, between 1991 and 2004. Reported data on educational level was used as a proxy for socioeconomic status to assess changes in female stature in relation to their social class. Results show that female stature in the sample increases during the time period considered (mean stature: 160.8 cm in 1966 and 161.1 cm in 1982), but not consistently. In addition, women of higher educational level are systematically taller than their lower educational level counterparts (mean stature difference between highest and lowest educational level groups is 4.2 cm). Compared to males, mean stature increase in females was about 75% less. Although the time period considered is short, this study documents important socioeconomic differences in female stature and is the first to report stature changes over time in Portuguese women.
Under Siege : Journal Publishing in the 1990s
Authors: McCullough Karen M.
Published: February 2014

Budget cutbacks are the theme of the '90s, and all aspects of advanced education are under intense pressure from severely reduced federal and provincial funding. The realm of scholarly communication is no exception. At a time of rising production costs, reduced postal subsidies, and subscription cancellations from under-funded university libraries, publishers of scholarly journals are now faced with the outright elimination of funding sources such as the Scientific Publication Grants Program of the Natural Sciences and Engineering Research Council of Canada (NSERC). According to NSERC, the support of scientific journals is a "non-core program" and is therefore being terminated to allow more funding to be directed to research grants. It is difficult to understand how the dissemination of knowledge came to be defined as a non-core program. The goal of ensuring adequate funds for the direct costs of conducting research is certainly laudable. Nevertheless, the loss, through inadequate funding, of scholarly journals as a major forum for scientists to communicate the results of their work has serious consequences for the entire scientific endeavour. There is little point in funding research that will remain unknown to the broader academic community and to Canadian tax-payers who support that community. Such a move could easily result in the research being available only to a privileged few (relatively speaking) through informal networks of communication such as the Internet. ... The move to on-line publishing may somewhat ease the budgetary pressures on journal support programs and university libraries as more and more new journals are offered directly in the electronic media rather than in print. ... Until such time as the print journal has disappeared, publishers will continue to seek ways to make the production process as efficient and cost-effective as possible, while maintaining the quality and integrity of scholarly journals. ... Fiscally responsible journal management means maintaining subscriber rates that will cover the costs of production and distribution. But we need to look elsewhere to cover the myriad other costs associated with scholarly publishing. ...
Editorial: On Editorials!
Authors: McCullough Karen
Published: February 2014

Given today's exciting and rapidly evolving developments in the Canadian North, the practice of masthead editorials was initiated to provide some degree of topicality to the multidisciplinary journal Arctic. This practice has resulted, much to our delight, in a substantial increase in letters to the editor - some commending and others strongly disagreeing with the trenchant and thought-provoking ideas put forth in the editorials. An editorial is an opinion piece or proposal written by an individual or group of individuals who wish to express a particular viewpoint on an issue of current relevance. The masthead editorial in Arctic is specifically designed to promote feedback from the readership and encourage our members to actively participate in the scholarly debate of important events and issues affecting the North now and in the future. A more active participation by the members through guest editorials and letters to the editors can only serve to enhance the value of and interest in the journal. ...
Individual differences in the interpretation of ambiguous statements about time
Authors: Duffy Sarah E. , Feist Michele I.
Published: February 2014

What factors influence the ways in which people resolve ambiguity? In English, two contrasting perspectives are implicit in deictic temporal expressions: the Moving Time metaphor conceptualizes time as moving forward towards the ego and the Moving Ego metaphor conceptualizes the ego as moving forward towards the future (Clark 1973). We examine the ambiguity arising from these two conceptualizations, claimed to be equally likely in a “neutral” context (Boroditsky and Ramscar 2002). Whereas previous studies have demonstrated that exposure to a spatial situation related to one interpretation may influence the resolution of the ambiguity (e.g. Boroditsky 2000; Nunez 2007), we focus on the lifestyle and personality factors of the participants as potential additional influences on ambiguity resolution in the interpretation of temporal metaphors. Experiment 1 asks whether lifestyle might influence an individual's approach to time and resulting resolution of temporal ambiguity, comparing preferred responses from two groups of participants with very different demands on the structuring of time: university students and administrators. We observed a difference between the two groups, with administrators more frequently adopting the Moving Time perspective and students, the Moving Ego perspective. Experiment 2 examines personality-related differences, focusing specifically on individual differences in procrastination (Lay 1986) and conscientiousness (John 1990). We observed a significant effect with participants who adopted the Moving Ego perspective reporting higher procrastination scores and lower conscientiousness scores than participants who adopted the Moving Time perspective. Experiment 3 investigates further personality-related differences, focusing specifically on individual differences in extroversion (John 1990). We observed a relationship between extroversion and disambiguation responses, with participants who adopted the Moving Ego perspective evidencing higher levels of extroversion. Taken together, the results from these three studies suggest that individual differences in lifestyle and personality may influence people's perspectives on the movement of events in time and their concomitant interpretation of temporally ambiguous utterances, precluding a universal “neutral” context within which language is interpreted.
The processing of verb-argument constructions is sensitive to form, function, frequency, contingency and prototypicality
Authors: Ellis Nick C. , O'Donnell Matthew Brook , Römer Ute
Published: February 2014

We used free association and verbal fluency tasks to investigate verb-argument constructions (VACs) and the ways in which their processing is sensitive to statistical patterns of usage (verb type-token frequency distribution, VAC-verb contingency, verb-VAC semantic prototypicality). In experiment 1, 285 native speakers of English generated the first word that came to mind to fill the V slot in 40 sparse VAC frames such as `he ____ across the. . . .', `it ____ of the. . . .', etc. In experiment 2, 40 English speakers generated as many verbs that fit each frame as they could think of in a minute. For each VAC, we compared the results from the experiments with corpus analyses of verb selection preferences in 100 million words of usage and with the semantic network structure of the verbs in these VACs. For both experiments, multiple regression analyses predicting the frequencies of verb types generated for each VAC show independent contributions of (i) verb frequency in the VAC, (ii) VAC-verb contingency and (iii) verb prototypicality in terms of centrality within the VAC semantic network. VAC processing involves rich associations, tuned by verb type and token frequencies and their contingencies of usage, which interface syntax, lexis and semantics. We consider the implications for the mental representation of VACs.
Chemical and ultrastructural changes in compound middle lamella (CML) regions of softwoods thermally modified by the Termovuoto process
Authors: Gao Jie , Kim Jong Sik , Terziev Nasko , Allegretti Ottaviano , Daniel Geoffrey
Published: February 2014

Silver fir and Norway spruce wood have been thermally modified (TMW) for 3–4 h at 160°C, 180°C, 200°C, and 220°C by means of the thermovacuum process (Termovuoto), and the ultrastructural and chemical changes in the compound middle lamella (CML), including the middle lamella cell corner (MLcc) regions (CMLcc), were investigated. Severe anatomical and histochemical changes were prominent above treatment temperatures of 200°C; thus, woods treated at 220°C for 4 h were in focus. Immunocytochemical studies showed that noncellulosic polysaccharides, such as pectin, xyloglucan, xylan, and mannan, were significantly degraded in CMLcc regions of TMWs. After treatment, the CMLcc regions were composed almost entirely of modified lignin with increased amounts of acidic groups. With cytochemical staining for lignin, many electron dense particulates were detected in the CMLcc regions of TMWs, indicating early degradation/alteration by the Termovuoto treatment.
Antidepressant, anxiolytic, and anticataleptic effects of aqueous leaf extract of Antiaris toxicaria Lesch. (Moraceae) in mice: possible mechanisms of actions
Authors: Agbaje Esther O. , Ishola Ismail O. , Oniyire Joel A.
Published: February 2014

Background: The leaves of Antiaris toxicaria Lesch. (Moraceae) are used by traditional medicine practitioners in southwest Nigeria in the management of epilepsy, wounds, and neurological disorders. Hence, this study was undertaken to investigate the effect of the aqueous leaf extract of A. toxicaria on the central nervous system.

Methods: One hour after administration of A. toxicaria [50–300 mg/kg orally (p.o.)], its antidepressant effect was evaluated using the forced swimming test (FST), anxiolytic effect using elevated plus maze (EPM) test, and anticataleptic effect using haloperidol-induced catalepsy, whereas its effects on hypnosis and motor coordination were studied using hexobarbitone-induced sleeping time and open-field tests, respectively, in mice.

Results:
Antiaris toxicaria (300 mg/kg) significantly increased swimming activity (36.88%) and reduced immobility time (38.54%). Pretreatment of mice with prazosin (an α1-adrenoceptor antagonist), sulpiride (a D2 receptor antagonist), and l-N
G-nitro-arginine (nitric oxide synthase inhibitor) 15 min before A. toxicaria (300 mg/kg p.o.) treatment significantly prevented its antidepressant-like effect by 35.58%, 53.30%, and 56.11%, respectively, in the FST. However, pretreatment with metergoline (5-HT2 receptor antagonist), and atropine (muscarinic cholinergic antagonist) failed to reverse this effect. Interestingly, A. toxicaria (50 mg/kg) significantly increased open-arm exploration in the EPM by 70.31%, which was reversed by 82.66% in the presence of flumazenil [3 mg/kg intraperitoneally (i.p.)]. Haloperidol (1 mg/kg i.p.) induced cataleptic behavior in mice, which was reversed by A. toxicaria (300 mg/kg) (p<0.001) treatment.

Conclusions: The results suggest that A. toxicaria possesses an antidepressant-like effect involving interaction with α1-adrenoceptor, D2 dopamine receptor, and nitrergic pathway; an anxiolytic-like effect linked to the benzodiazepine system; and a neuroprotective effect.
Arm Movements Induced by Electrical Microstimulation in the Superior Colliculus of the Macaque Monkey
Authors: Philipp Roland , Hoffmann Klaus-Peter
Published: February 2014

Neuronal activity in the deep layers of the macaque (Macaca mulatta) superior colliculus (SC) and the underlying reticular formation is correlated with the initiation and execution of arm movements (Werner, 1993). Although the correlation of this activity with EMGs of proximal arm muscles is as strong as in motor cortex (Werner et al., 1997a; Stuphorn et al., 1999), little is known about the influence of electrical microstimulation in the SC on the initiation and trajectories of arm movements. Our experiments on three macaque monkeys clearly show that arm movements can be elicited by electrical microstimulation in the deep layers of the lateral SC and underlying reticular formation. The most extensively trained monkey, M1, extended his arm toward the screen in front of him more or less stereotypically upon electrical SC stimulation. In two other monkeys, M2 and M3, a larger repertoire of arm movements were elicited, categorized into three movement types, and compared before (M3) and after (M2 and M3) training: twitch (56% vs 62%), lift (6% vs 5%), and extend (37% vs 32%), respectively. Therefore, arm movements induced by electrical stimulation in the monkey SC represent a further component of the functional repertoire of the SC using its impact on motoneurons in the spinal cord, probably via premotor neurons in the brainstem, as well as on structures involved in executing more complex movements such as target-directed reaching. Therefore, the macaque SC could be involved directly in the initiation, execution, and amendment of arm and hand movements.
Intracellular Correlates of Stimulus-Specific Adaptation
Authors: Hershenhoren Itai , Taaseh Nevo , Antunes Flora M. , Nelken Israel
Published: February 2014

Stimulus-specific adaptation (SSA) is the reduction in response to a common stimulus that does not generalize, or only partially generalizes, to rare stimuli. SSA is strong and widespread in primary auditory cortex (A1) of rats, but is weak or absent in the main input station to A1, the ventral division of the medial geniculate body. To study SSA in A1, we recorded neural activity in A1 intracellularly using sharp electrodes. We studied the responses to tone pips of the same frequency in different contexts: as Standard and Deviants in Oddball sequences; in equiprobable sequences; in sequences consisting of rare tone presentations; and in sequences composed of many different frequencies, each of which was rare. SSA was found both in subthreshold membrane potential fluctuations and in spiking responses of A1 neurons. SSA for changes in frequency was large at a frequency difference of 44% between Standard and Deviant, and clearly present with tones separated by as little as 4%, near the behavioral frequency difference limen in rats. When using equivalent measures, SSA in spiking responses was generally larger than the SSA at the level of the membrane potential. This effect can be traced to the nonlinearity of the transformation between membrane potential to spikes. Using the responses to the same tone in different contexts made it possible to demonstrate that cortical SSA could not be fully explained by adaptation in narrow frequency channels, even at the level of the membrane potential. We conclude that local processing significantly contributes to the generation of cortical SSA.
Postsynaptic FMRP Promotes the Pruning of Cell-to-Cell Connections among Pyramidal Neurons in the L5A Neocortical Network
Authors: Patel Ankur B. , Loerwald Kristofer W. , Huber Kimberly M. , Gibson Jay R.
Published: February 2014

Pruning of structural synapses occurs with development and learning. A deficit in pruning of cortical excitatory synapses and the resulting hyperconnectivity is hypothesized to underlie the etiology of fragile X syndrome (FXS) and related autistic disorders. However, clear evidence for pruning in neocortex and its impairment in FXS remains elusive. Using simultaneous recordings of pyramidal neurons in the layer 5A neocortical network of the wild-type (WT) mouse to observe cell-to-cell connections in isolation, we demonstrate here a specific form of “connection pruning.” Connection frequency among pyramidal neurons decreases between the third and fifth postnatal weeks, indicating a period of connection pruning. Over the same interval in the FXS model mouse, theFmr1knock-out (KO), connection frequency does not decrease. Therefore, connection frequency in the fifth week is higher in theFmr1KO compared with WT, indicating a state of hyperconnectivity. These alterations are due to postsynaptic deletion ofFmr1. At early ages (2 weeks), postsynapticFmr1promoted the maturation of cell-to-cell connections, but not their number. These findings indicate that impaired connection pruning at later ages, and not an excess of connection formation, underlies the hyperconnectivity in theFmr1KO mouse. FMRP did not appear to regulate synapses individually, but instead regulated cell-to-cell connectivity in which groups of synapses mediating a single cell-to-cell connection are uniformly removed, retained, and matured. Although we do not link connection pruning directly to the pruning of structurally defined synapses, this study nevertheless provides an important model system for studying altered pruning in FXS.
Nonvisual Complex Spike Signals in the Rabbit Cerebellar Flocculus
Authors: Winkelman Beerend H. J. , Belton Tim , Suh Minah , Coesmans Michiel , Morpurgo Menno M. , Simpson John I.
Published: February 2014

In addition to the well-known signals of retinal image slip, floccular complex spikes (CSs) also convey nonvisual signals. We recorded eye movement and CS activity from Purkinje cells in awake rabbits sinusoidally oscillated in the dark on a vestibular turntable. The stimulus frequency ranged from 0.2 to 1.2 Hz, and the velocity amplitude ranged from 6.3 to 50°/s. The average CS modulation was evaluated at each combination of stimulus frequency and amplitude. More than 75% of the Purkinje cells carried nonvisual CS signals. The amplitude of this modulation remained relatively constant over the entire stimulus range. The phase response of the CS modulation in the dark was opposite to that during the vestibulo-ocular reflex (VOR) in the light. With increased frequency, the phase response systematically shifted from being aligned with contraversive head velocity toward peak contralateral head position. At fixed frequency, the phase response was dependent on peak head velocity, indicating a system nonlinearity. The nonvisual CS modulation apparently reflects a competition between eye movement and vestibular signals, resulting in an eye movement error signal inferred from nonvisual sources. The combination of this error signal with the retinal slip signal in the inferior olive results in a net error signal reporting the discrepancy between the actual visually measured eye movement error and the inferred eye movement error derived from measures of the internal state. The presence of two error signals requires that the role of CSs in models of the floccular control of VOR adaption be expanded beyond retinal slip.
Neural Responses to Target Features outside a Search Array Are Enhanced during Conjunction but Not Unique-Feature Search
Authors: Painter David R. , Dux Paul E. , Travis Susan L. , Mattingley Jason B.
Published: February 2014

The visual world is typically too complex to permit full apprehension of its content from a single fixation. Humans therefore use visual search to direct attention and eye movements to locations or objects of interest in cluttered scenes. Psychophysical investigations have revealed that observers can select target elements from within an array of distractors on the basis of their spatial location or simple features, such as color. It remains unclear, however, how stimuli that lie outside the current search array are represented in the visual system. To investigate this, we recorded continuous neural activity using EEG while participants searched a foveal array of colored targets and distractors, and ignored irrelevant objects in the periphery. Search targets were defined either by a unique feature within the array or by a conjunction of features. Objects outside the array could match the target or distractor color within the array, or otherwise possessed a baseline (neutral) color present only in the periphery. The search array and irrelevant peripheral objects flickered at unique rates and thus evoked distinct frequency-tagged neural oscillations. During conjunction but not unique-feature search, target-colored objects outside the array evoked enhanced activity relative to distractor-colored and neutral objects. The results suggest that feature-based selection applies to stimuli at ignored peripheral locations, but only when central targets compete with distractors within the array. Distractor-colored and neutral objects evoked equivalent oscillatory responses, suggesting that feature-based selection at ignored locations during visual search arises exclusively from enhancement rather than suppression of neural activity.
Large Somatic Synapses on Neurons in the Ventral Lateral Lemniscus Work in Pairs
Authors: Berger Christina , Meyer Elisabeth M.M. , Ammer Julian J. , Felmy Felix
Published: February 2014

In the auditory system, large somatic synapses convey strong excitation that supports temporally precise information transfer. The information transfer of such synapses has predominantly been investigated in the endbulbs of Held in the anterior ventral cochlear nucleus and the calyx of Held in the medial nucleus of the trapezoid body. These large synapses either work as relays or integrate over a small number of inputs to excite the postsynaptic neuron beyond action potential (AP) threshold. In the monaural system, another large somatic synapse targets neurons in the ventral nucleus of the lateral lemniscus (VNLL). Here, we comparatively analyze the mechanisms of synaptic information transfer in endbulbs in the VNLL and the calyx of Held in juvenile Mongolian gerbils. We find that endbulbs in the VNLL are functionally surface-scaled versions of the calyx of Held with respect to vesicle availability, release efficacy, and synaptic peak currents. This functional scaling is achieved by different calcium current kinetics that compensate for the smaller AP in VNLL endbulbs. However, the average postsynaptic current in the VNLL fails to elicit APs in its target neurons, even though equal current suffices to generate APs in neurons postsynaptic to the calyx of Held. In the VNLL, a postsynaptic A-type outward current reduces excitability and prevents AP generation upon a single presynaptic input. Instead, coincidence detection of inputs from two converging endbulbs is ideal to reliably trigger APs. Thus, even large endbulbs do not guarantee one-to-one AP transfer. Instead, information flow appears regulated by circuit requirements.
Representation of Outcome Risk and Action in the Anterior Caudate Nucleus
Authors: Yanike Marianna , Ferrera Vincent P.
Published: February 2014

The anterior caudate nucleus is essential for goal-directed behavior because it links outcome information to actions. It is well known that caudate neurons provide a variety of reward-related and action signals. However, it is still unclear how the two signals are integrated. We investigated whether and how outcome risk modulates spatial representation. We recorded neural activity in the anterior caudate nucleus while monkeys made saccades to multiple spatial targets, each associated with either fixed (safe) or variable (risky) amount of reward. We report that individual neurons combined the outcome reward signal with spatial information about the direction of saccades. These signals could be reliably read out from the populations of neurons. Moreover, the prospect of a risky outcome improved the quality of spatial information. These results provide direct evidence that global spatial representation in the caudate is modulated by outcome, which can be important for flexible control of behavior, particularly during learning and habit formation, when outcomes vary.
ASIC1a Activation Enhances Inhibition in the Basolateral Amygdala and Reduces Anxiety
Authors: Pidoplichko Volodymyr I. , Aroniadou-Anderjaska Vassiliki , Prager Eric M. , Figueiredo Taiza H. , Almeida-Suhett Camila P. , Miller Steven L. , Braga Maria F. M.
Published: February 2014

The discovery that even small changes in extracellular acidity can alter the excitability of neuronal networks via activation of acid-sensing ion channels (ASICs) could have therapeutic application in a host of neurological and psychiatric illnesses. Recent evidence suggests that activation of ASIC1a, a subtype of ASICs that is widely distributed in the brain, is necessary for the expression of fear and anxiety. Antagonists of ASIC1a, therefore, have been proposed as a potential treatment for anxiety. The basolateral amygdala (BLA) is central to fear generation, and anxiety disorders are characterized by BLA hyperexcitability. To better understand the role of ASIC1a in anxiety, we attempted to provide a direct assessment of whether ASIC1a activation increases BLA excitability. In rat BLA slices, activation of ASIC1a by low pH or ammonium elicited inward currents in both interneurons and principal neurons, and increased spontaneous IPSCs recorded from principal cells significantly more than spontaneous EPSCs. Epileptiform activity induced by high potassium and low magnesium was suppressed by ammonium. Antagonism of ASIC1a decreased spontaneous IPSCs more than EPSCs, and increased the excitability of the BLA network, as reflected by the pronounced increase of evoked field potentials, suggesting that ASIC1a channels are active in the basal state.In vivoactivation or blockade of ASIC1a in the BLA suppressed or increased, respectively, anxiety-like behavior. Thus, in the rat BLA, ASIC1a has an inhibitory and anxiolytic function. The discovery of positive ASIC1a modulators may hold promise for the treatment of anxiety disorders.
Absence of Transient Receptor Potential Vanilloid-1 Accelerates Stress-Induced Axonopathy in the Optic Projection
Authors: Ward Nicholas J. , Ho Karen W. , Lambert Wendi S. , Weitlauf Carl , Calkins David J.
Published: February 2014

How neurons respond to stress in degenerative disease is of fundamental importance for identifying mechanisms of progression and new therapeutic targets. Members of the transient receptor potential (TRP) family of cation-selective ion channels are candidates for mediating stress signals, since different subunits transduce a variety of stimuli relevant in both normal and pathogenic physiology. We addressed this possibility for the TRP vanilloid-1 (TRPV1) subunit by comparing how the optic projection ofTrpv1−/−mice and age-matched C57 controls responds to stress from elevated ocular pressure, the critical stressor in the most common optic neuropathy, glaucoma. Over a 5 week period of elevated pressure induced by microbead occlusion of ocular fluid,Trpv1−/−accelerated both degradation of axonal transport from retinal ganglion cells to the superior colliculus and degeneration of the axons themselves in the optic nerve. Ganglion cell body loss, which is normally later in progression, occurred in nasal sectors ofTrpv1−/−but not C57 retina. Pharmacological antagonism of TRPV1 in rats similarly accelerated ganglion cell axonopathy. Elevated ocular pressure resulted in differences in spontaneous firing rate and action potential threshold current inTrpv1−/−ganglion cells compared with C57. In the absence of elevated pressure, ganglion cells in the two strains had similar firing patterns. Based on these data, we propose that TRPV1 may help neurons respond to disease-relevant stressors by enhancing activity necessary for axonal signaling.