bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterisation of the role of Vrp1 in cell fusion during the development of visceral muscle of Drosophila melanogaster
Authors: Eriksson Therese , Varshney Gaurav , Aspenström Pontus , Palmer Ruth H
Published: August 2010

Background

InDrosophilamuscle cell fusion takes place both during the formation of the somatic mesoderm and the visceral mesoderm, giving rise to the skeletal muscles and the gut musculature respectively. The core process of myoblast fusion is believed to be similar for both organs. The actin cytoskeleton regulator Verprolin acts by binding to WASP, which in turn binds to the Arp2/3 complex and thus activates actin polymerization. While Verprolin has been shown to be important for somatic muscle cell fusion, the function of this protein in visceral muscle fusion has not been determined.

Results

Verprolin is specifically expressed in the fusion competent myoblasts of the visceral mesoderm, suggesting a role in visceral mesoderm fusion. We here describe a novel Verprolin mutant allele which displays subtle visceral mesoderm fusion defects in the form of mislocalization of the immunoglobulin superfamily molecule Duf/Kirre, which is required on the myoblast cell surface to facilitate attachment between cells that are about to fuse, indicating a function for Verprolin in visceral mesoderm fusion. We further show that Verprolin mutant cells are capable of both migrating and fusing and that the WASP-binding domain of Verprolin is required for rescue of the Verprolin mutant phenotype.

Conclusions

Verprolin is expressed in the visceral mesoderm and plays a role in visceral muscle fusion as shown by mislocalization of Duf/Kirre in theVerprolinmutant, however it is not absolutely required for myoblast fusion in either the visceral or the somatic mesoderm.
Evaluation of HIV protease and nucleoside reverse transcriptase inhibitors on proliferation, necrosis, apoptosis in intestinal epithelial cells and electrolyte and water transport and epithelial barrier function in mice
Authors: Braga Neto Manuel B , Aguiar Carolina V , Maciel Jamilly G , Oliveira Bruna MC , Sevilleja Jesus E , Oriá Reinaldo B , Brito Gerly AC , Warren Cirle A , Guerrant Richard L , Lima Aldo AM
Published: August 2010

Background

Protease inhibitors (PI's) and reverse transcriptase drugs are important components of highly active antiretroviral therapy (HAART) for treating human acquired immunodeficiency syndrome (AIDS). Long-term clinical therapeutic efficacy and treatment compliance of these agents have been limited by undesirable side-effects, such as diarrhea. This study aims to investigate the effects of selected antiretroviral agents on intestinal histopathology and functionin vivoand on cell proliferation and deathin vitro.

Methods

Selected antiretroviral drugs were given orally over 7 days, to Swiss mice, as follows: 100 mg/kg of nelfinavir (NFV), indinavir (IDV), didanosine (DDI) or 50 mg/kg of zidovudine (AZT). Intestinal permeability measured by lactulose and mannitol assays; net water and electrolyte transport, in perfused intestinal segments; and small intestinal morphology and cell apoptosis were assessed in treated and control mice.In vitrocell proliferation was evaluated using the WST-1 reagent and apoptosis and necrosis by flow cytometry analysis.

Results

NFV, IDV, AZT and DDI caused significant reductions in duodenal and in jejunal villus length (p < 0.05). IDV and AZT increased crypt depth in the duodenum and AZT increased crypt depth in the jejunum. NFV, AZT and DDI significantly decreased ileal crypt depth. All selected antiretroviral drugs significantly increased net water secretion and electrolyte secretion, except for DDI, which did not alter water or chloride secretion. Additionally, only NFV significantly increased mannitol and lactulose absorption. NFV and IDV caused a significant reduction in cell proliferationin vitroat both 24 h and 48 h. DDI and AZT did not alter cell proliferation. There was a significant increase in apoptosis rates in IEC-6 cells after 24 h with 70 ug/mL of NFV (control: 4.7% vs NFV: 22%) while IDV, AZT and DDI did not show any significant changes in apoptosis compared to the control group. In jejunal sections, IDV and NFV significantly increased the number of TUNEL positive cells.

Conclusion

The PI's, NFV and IDV, increased cell apoptosisin vivo, water and electrolyte secretion and intestinal permeability and decreased villus length and cell proliferation. NFV was the only drug tested that increased cell apoptosisin vitro. The nucleoside reverse transcriptase inhibitors, AZT and DDI, did not affect cell apoptosis or proliferation. These findings may partly explain the intestinal side-effects associated with PI's.
Genome wide screen identifies microsatellite markers associated with acute adverse effects following radiotherapy in cancer patients
Authors: Michikawa Yuichi , Suga Tomo , Ishikawa Atsuko , Hayashi Hideki , Oka Akira , Inoko Hidetoshi , Iwakawa Mayumi , Imai Takashi
Published: August 2010

Background

The response of normal tissues in cancer patients undergoing radiotherapy varies, possibly due to genetic differences underlying variation in radiosensitivity.

Methods

Cancer patients (n = 360) were selected retrospectively from the RadGenomics project. Adverse effects within 3 months of radiotherapy completion were graded using the National Cancer Institute Common Toxicity Criteria; high grade group were grade 3 or more (n = 180), low grade group were grade 1 or less (n = 180). Pooled genomic DNA (gDNA) (n = 90 from each group) was screened using 23,244 microsatellites. Markers with different inter-group frequencies (Fisher exact testP< 0.05) were analyzed using the remaining pooled gDNA. Silencing RNA treatment was performed in cultured normal human skin fibroblasts.

Results

Forty-seven markers had positive association values; including one in theSEMA3Apromoter region (P = 1.24 × 10-5).SEMA3Aknockdown enhanced radiation resistance.

Conclusions

This study identified 47 putative radiosensitivity markers, and suggested a role forSEMA3Ain radiosensitivity.
A progressive declining in the burden of malaria in north-eastern Tanzania
Authors: Mmbando Bruno P , Vestergaard Lasse S , Kitua Andrew Y , Lemnge Martha M , Theander Thor G , Lusingu John PA
Published: August 2010

Background

The planning and assessment of malaria interventions is complicated due to fluctuations in the burden of malaria over time. Recently, it has been reported that the burden of malaria in some parts of Africa has declined. However, community-based longitudinal data are sparse and the reasons for the apparent decline are not well understood.

Methods

Malaria prevalence and morbidity have been monitored in two villages in north-eastern Tanzania; a lowland village and a highland village from 2003 to 2008. Trained village health workers treated presumptive malaria with the Tanzanian first-line anti-malarial drug and collected blood smears that were examined later. The prevalence of malaria parasitaemia across years was monitored through cross-sectional surveys.

Results

The prevalence of malaria parasitaemia in the lowland village decreased from 78.4% in 2003 to 13.0% in 2008, whereas in the highland village, the prevalence of parasitaemia dropped from 24.7% to 3.1% in the same period. Similarly, the incidence of febrile malaria episodes in the two villages dropped by almost 85% during the same period and there was a marked reduction in the number of young children who suffered from anaemia in the lowland village.

Conclusion

There has been a marked decline in malaria in the study villages during the past few years. This decline is likely to be due to a combination of factors that include improved access to malaria treatment provided by the trained village helpers, protection from mosquitoes by increased availability of insecticide-impregnated bed nets and a reduced vector density. If this decline in malaria morbidity is sustained, it will have a marked effect on the disease burden in this part of Tanzania.
A mouse model to study infection against porcine circovirus type 2: viral distribution and lesions in mouse
Authors: Li Jun , Yuan Xiaoyuan , Zhang Chaofan , Miao Lanfei , Wu Jiaqiang , Shi Jianli , Xu Shaojian , Cui Shangjin , Wang Jinbao , Ai Hongbin
Published: August 2010

Background

Little information is known about viral distribution and transmission of porcine circovirus type 2 (PCV2) in species other than swine. It is still a debated topic whether the PCV2 could be infected and caused clinical lesions. Our study is aimed to estimate the susceptibility of Kunming mouse to PCV2. Forty-eight, 6-week-old Kunming mice were randomly divided into four groups. Group A (C1-C12) was inoculated with PK-15 cell culture as a control group. Group B (sPCV1-12) was inoculated orally and intramuscularly with PCV2 (106.2TCID50/ml). Group C (mPCV1-12) was inoculated orally and intramuscularly with PCV2 (106.2TCID50/ml) and a booster inoculation at days 14 and 28 after the first inoculation. Group D (MixPCV1-12) was unvaccinated but released into Group C. Each group was sacrificed at 7, 14, 28, and 42 days post-inoculation, respectively. Necropsy was checked on every mouse. Sera samples were collected for the test of PCV2 specific antibody. Tissues were collected for histopathology study and polymerase chain reaction (PCR).

Results

The results showed that viral replication, seroconversion, and microscopic lesions were found in inoculated mice. Continuous existence of PCV2 viruses in lymph nodes have been confirmed by PCR, which took at least seven days for the virus to be transferred into other organs from the primary interface, and the diffusion to thymus had been retarded for seven days. Special PCV2 antibody could be found in PCV2 inoculation mice and was significantly higher than that in the control. Further more, microscopic lesions and the main target of PCV2 focused in the lymph nodes with a characteristic depletion and occasional necrosis of lymphocytes in the cortex and paracortex were found in inoculated mice.

Conclusions

The Kunming mouse could be infected by PCV2 virus and used as a PCV2 infected experimental model.
Dynamics of Sundarban estuarine ecosystem: eutrophication induced threat to mangroves
Authors: Manna Suman , Chaudhuri Kaberi , Bhattacharyya Somenath , Bhattacharyya Maitree
Published: August 2010

Background

Sundarbans is the largest chunk of mangrove forest and only tiger mangrove land in the world. Compared to the rich species diversity and uniqueness, very few studies have so far been conducted here, mainly due to its inaccessibility. This study explores water quality, density of biomass, species diversity, phytoplankton abundance and bacterial population of a tidal creek in Sunderban estuary during the post and pre monsoon period of 2008-09.

Results

Phytoplankton community was observed to be dominated by diatoms (Biacillariophyceae) followed by Pyrrophyceae (Dinoflagellates) and Chlorophyceae. A total of 46 taxa belonging to 6 groups were recorded. Other algal groups were Cyanophyceae, Euglenophyceae and Chrysophyceae. Species diversity was highest in summer (March) and lowest in winter season (November) in all the sample stations indicating its close correlation with ambient temperature. Species evenness was fairly high in all five stations throughout the study period. Present study indicated that dissolved oxygen, nutrients and turbidity are the limiting factors for the phytoplankton biomass. The estuary was in eutrophic condition (Chlorophyll-a ≥10 μg/L) in winter. During the month of May phytoplankton biomass declined and at high salinity level (21.2PSU) new phytoplankton species take over, which are definitely better resilient to the high saline environment. Bio-indicator species likePolykrikos schwartzil, Dinophysis norvegica and Prorocentrum concavumpoints to moderately polluted water quality of the estuary.

Conclusion

Eutrophication as well as presence of toxic Dinoflagellates and Cyanophyceae in the tidal creek of Sundarban estuary definitely revealed the deteriorated status of the water quality. The structure and function of the mangrove food web is unique, driven by both marine and terrestrial components. But little attention has been paid so far to the adaptive responses of mangrove biota to the various disturbances, and now our work unfolds the fact that marine status of Sundarban estuary is highly threatened which in turn will affect the ecology of the mangrove. This study indicates that ecosystem dynamics of the world heritage site Sundarban may facilitate bioinvasion putting a question mark on the sustainability of mangroves.
Ethnomedicinal uses of Hagenia abyssinica (Bruce) J.F. Gmel. among rural communities of Ethiopia
Authors: Assefa Biruktayet , Glatzel Gerhard , Buchmann Christine
Published: August 2010

Ethiopian communities highly depend on local plant resources to secure their subsistence and health. Local tree resources are exploited and used intensively for medicinal purposes. This study provides insight into the medicinal importance of Hagenia abyssinica as well as the degree of threat on its population. An ethnobotanical study was carried out to document medicinal uses of Hagenia abyssinica by rural communities of North and Southeastern Ethiopia. The study was conducted using an integrated approach of group discussions, observation, a local market survey and interviews. A total of 90 people were interviewed among whom elderly and traditional healers were the key informants. Societies in the study sites still depend on Hagenia abyssinica for medicine. All plant parts are used to treat different aliments. Tree identification, collection and utilization were different among the studied communities. In spite of its significance, interest in utilizing flowers of Hagenia abyssinica as an anthelmintic seems to be diminishing, notably among young people. This is partly because the medicine can be harmful when it is taken in large quantities. Nowadays, the widely used Hagenia abyssinica is endangered primarily due to various anthropogenic impacts. This in turn may become a threat for the associated knowledge. It is recommended to assist communities in documenting their traditional knowledge. Measures for conserving species are urgently needed.
Predictive biomarker discovery through the parallel integration of clinical trial and functional genomics datasets
Authors: Swanton Charles , Larkin James M , Gerlinger Marco , Eklund Aron C , Howell Michael , Stamp Gordon , Downward Julian , Gore Martin , Futreal P Andrew , Escudier Bernard , Andre Fabrice , Albiges Laurence , Beuselinck Benoit , Oudard Stephane , Hoffmann Jens , Gyorffy Balázs , Torrance Chris J , Boehme Karen A , Volkmer Hansjuergen , Toschi Luisella , Nicke Barbara , Beck Marlene , Szallasi Zoltan
Published: August 2010

The European Union multi-disciplinary Personalised RNA interference to Enhance the Delivery of Individualised Cytotoxic and Targeted therapeutics (PREDICT) consortium has recently initiated a framework to accelerate the development of predictive biomarkers of individual patient response to anti-cancer agents. The consortium focuses on the identification of reliable predictive biomarkers to approved agents with anti-angiogenic activity for which no reliable predictive biomarkers exist: sunitinib, a multi-targeted tyrosine kinase inhibitor and everolimus, a mammalian target of rapamycin (mTOR) pathway inhibitor. Through the analysis of tumor tissue derived from pre-operative renal cell carcinoma (RCC) clinical trials, the PREDICT consortium will use established and novel methods to integrate comprehensive tumor-derived genomic data with personalized tumor-derived small hairpin RNA and high-throughput small interfering RNA screens to identify and validate functionally important genomic or transcriptomic predictive biomarkers of individual drug response in patients. PREDICT's approach to predictive biomarker discovery differs from conventional associative learning approaches, which can be susceptible to the detection of chance associations that lead to overestimation of true clinical accuracy. These methods will identify molecular pathways important for survival and growth of RCC cells and particular targets suitable for therapeutic development. Importantly, our results may enable individualized treatment of RCC, reducing ineffective therapy in drug-resistant disease, leading to improved quality of life and higher cost efficiency, which in turn should broaden patient access to beneficial therapeutics, thereby enhancing clinical outcome and cancer survival. The consortium will also establish and consolidate a European network providing the technological and clinical platform for large-scale functional genomic biomarker discovery. Here we review our current understanding of molecular mechanisms driving resistance to anti-angiogenesis agents, the current limitations of laboratory and clinical trial strategies and how the PREDICT consortium will endeavor to identify a new generation of predictive biomarkers.
Role of CD27/CD70 pathway of activation in immunity and tolerance
Authors: Denoeud Julie , Moser Muriel
Published: August 2010

The CD70/CD27 axis has gained increasing interest among the immunologists, because of its capacity to regulate immunity versus tolerance. Recent studies clearly show that expression of CD70 may prevent tolerance induced by antigen presentation in the steady-state, i.e., by nonactivated DCs. In addition, CD27 signaling appears critical for T cell expansion and survival and therefore, induction of long-term memory. It contributes to germinal center formation, B cell activation, and production of neutralizing antibodies but can also be subverted by viruses, in particular, during chronic infections. The potential role of the CD27/CD70 pathway in the course of inflammatory diseases, as in EAE, arthritis, and inflammatory bowel disease models, suggests that CD70 may be a target for immune intervention. Conversely, the potency of costimulation through CD27 suggests that the CD27/CD70 axis could be exploited for the design of anti-cancer vaccines.
The extracellular matrix and disease: an interview with Zena Werb
Authors: Kain Kristin H.
Published: August 2010

Zena Werb’s pioneering efforts brought recognition to the idea that the extracellular matrix has a profound influence in determining cell fate. Here, she discusses how a ‘rocky’ start in geophysics led her to a career that is changing the way we think about cancer.
Casein kinase 1 regulates human hypoxia-inducible factor HIF-1
Authors: Kalousi Alkmini , Mylonis Ilias , Politou Anastasia S. , Chachami Georgia , Paraskeva Efrosyni , Simos George
Published: August 2010

Hypoxia-inducible factor 1 (HIF-1), a transcriptional activator that mediates cellular response to hypoxia and a promising target of anticancer therapy, is essential for adaptation to low oxygen conditions, embryogenesis and tumor progression. HIF-1 is a heterodimer of HIF-1α, expression of which is controlled by oxygen levels as well as by various oxygen-independent mechanisms, and HIF-1β (or ARNT), which is constitutively expressed. In this work, we investigate the phosphorylation of the N-terminal heterodimerization (PAS) domain of HIF-1α and identify Ser247 as a major site of in vitro modification by casein kinase 1δ (CK1δ). Mutation of this site to alanine, surprisingly, enhanced the transcriptional activity of HIF-1α, a result phenocopied by inhibition or small interfering RNA (siRNA)-mediated silencing of CK1δ under hypoxic conditions. Conversely, overexpression of CK1δ or phosphomimetic mutation of Ser247 to aspartate inhibited HIF-1α activity without affecting its stability or nuclear accumulation. Immunoprecipitation and in vitro binding experiments suggest that CK1-dependent phosphorylation of HIF-1α at Ser247 impairs its association with ARNT, a notion also supported by modeling the structure of the complex between HIF-1α and ARNT PAS-B domains. We suggest that modification of HIF-1α by CK1 represents a novel mechanism that controls the activity of HIF-1 during hypoxia by regulating the interaction between its two subunits.
CHMP2B mutants linked to frontotemporal dementia impair maturation of dendritic spines
Authors: Belly Agnès , Bodon Gilles , Blot Béatrice , Bouron Alexandre , Sadoul Rémy , Goldberg Yves
Published: August 2010

The highly conserved ESCRT-III complex is responsible for deformation and cleavage of membranes during endosomal trafficking and other cellular activities. In humans, dominant mutations in the ESCRT-III subunit CHMP2B cause frontotemporal dementia (FTD). The decade-long process leading to this cortical degeneration is not well understood. One possibility is that, akin to other neurodegenerative diseases, the pathogenic protein affects the integrity of dendritic spines and synapses before any neuronal death. Using confocal microscopy and 3D reconstruction, we examined whether expressing the FTD-linked mutants CHMP2Bintron5 and CHMP2BΔ10 in cultured hippocampal neurons modified the number or structure of spines. Both mutants induced a significant decrease in the proportion of large spines with mushroom morphology, without overt degeneration. Furthermore, CHMP2BΔ10 induced a drop in frequency and amplitude of spontaneous excitatory postsynaptic currents, suggesting that the more potent synapses were lost. These effects seemed unrelated to changes in autophagy. Depletion of endogenous CHMP2B by RNAi resulted in morphological changes similar to those induced by mutant CHMP2B, consistent with dominant-negative activity of pathogenic mutants. Thus, CHMP2B is required for spine growth. Taken together, these results demonstrate that a mutant ESCRT-III subunit linked to a human neurodegenerative disease can disrupt the normal pattern of spine development.
ProbKnot: Fast prediction of RNA secondary structure including pseudoknots
Authors: Bellaousov Stanislav , Mathews David H.
Published: August 2010

It is a significant challenge to predict RNA secondary structures including pseudoknots. Here, a new algorithm capable of predicting pseudoknots of any topology, ProbKnot, is reported. ProbKnot assembles maximum expected accuracy structures from computed base-pairing probabilities in O(N2) time, where N is the length of the sequence. The performance of ProbKnot was measured by comparing predicted structures with known structures for a large database of RNA sequences with fewer than 700 nucleotides. The percentage of known pairs correctly predicted was 69.3%. Additionally, the percentage of predicted pairs in the known structure was 61.3%. This performance is the highest of four tested algorithms that are capable of pseudoknot prediction. The program is available for download at: http://rna.urmc.rochester.edu/RNAstructure.html.
Dilemmas of citizenship: Young people's conceptions of un/employment rights and responsibilities
Authors: Gibson Stephen
Published: August 2010

This paper draws on the concept of ideological dilemmas in order to explore how a sample of young people constructed potentially contrary themes of liberal citizenship in discussions of un/employment. The study took place in the context of recent policy developments in the UK which have sought to place a renewed emphasis upon notions of responsible citizenship in relation to both welfare and education policy. A total of 58 participants were interviewed in 24 semi‐structured group interviews. In response to direct questions on un/employment, participants could resolve dilemmas concerning welfare rights and the responsibility to contribute to society by emphasizing a criterion of effortfulness, thereby adopting a primarily individualistic explanation of unemployment. In other contexts however, this could be replaced by an emphasis on social explanations of unemployment. In particular, participants could treat immigration as a cause of unemployment. These findings are interpreted in terms of people's capacity to construct rhetorical strategies based upon different ideological themes in particular contexts. They are discussed in relation to previous research on social policy discourse and recent debates regarding the appropriateness of seeking to identify ideological themes in discourse.
Dielectric and thermal properties of epoxy/boron nitride nanotube composites
Authors: Zhi Chunyi Y. , Bando Yoshio , Terao Takeshi , Tang Chengchun , Golberg Dmitri
Published: August 2010

We report the fabrication of and investigations into the dielectric and thermal properties of epoxy/boron nitride nanotube (BNNT) composites. It was found that BNNT fillers can effectively adjust the dielectric constant of epoxy. Moreover, the thermal conductivity of epoxy was improved by up to 69 % with 5 wt % BNNTs. Our studies indicate that BNNTs are promising nanofillers for polymers, to obtain and control an adjustable dielectric property and improved thermal conductivity.
Affine Tallini Sets and Grassmannians
Authors: Ferrara Dentice Eva , Lo Re Pia Maria
Published: August 2010

In 1982/1983 A. Bichara and F. Mazzocca characterized the Grassmann space Gr(h, 𝔸) of index h of an affine space 𝔸 of dimension at least 3 over a skew-field K by means of the intersection properties of the three disjoint families of maximal singular subspaces of Gr(h, 𝔸) and, till now, their result represents the only known characterization of Gr(h, 𝔸). If K is a commutative field and 𝔸 has finite dimension m, then the image under the well known Plücker morphism is a proper subset of PG(M, K), , called the affine Grassmannian of the h-subspaces of 𝔸. The aim of this paper is to introduce the notion of Affine Tallini Set and provide a natural and intrinsic characterization of from the point-line geometry point of view. More precisely, we prove that if a projective space over a skew-field K contains an Affine Tallini Set Δ satisfying suitable axioms on “perp” of lines, then the skew-field K is forced to be a commutative field and Δ is an affine Grassmannian, up to projections. Furthermore, several results concerning Affine Tallini Sets are stated and proved.
Leading Tip Drives Soma Translocation via Forward F-Actin Flow during Neuronal Migration
Authors: He Min , Zhang Zheng-hong , Guan Chen-bing , Xia Di , Yuan Xiao-bing
Published: August 2010

Neuronal migration involves coordinated extension of the leading process and translocation of the soma, but the relative contribution of different subcellular regions, including the leading process and cell rear, in driving soma translocation remains unclear. By local manipulation of cytoskeletal components in restricted regions of cultured neurons, we examined the molecular machinery underlying the generation of traction force for soma translocation during neuronal migration. In actively migrating cerebellar granule cells in culture, a growth cone (GC)-like structure at the leading tip exhibits high dynamics, and severing the tip or disrupting its dynamics suppressed soma translocation within minutes. Soma translocation was also suppressed by local disruption of F-actin along the leading process but not at the soma, whereas disrupting microtubules along the leading process or at the soma accelerated soma translocation. Fluorescent speckle microscopy using GFP-α-actinin showed that a forward F-actin flow along the leading process correlated with and was required for soma translocation, and such F-actin flow depended on myosin II activity. In migrating neurons, myosin II activity was high at the leading tip but low at the soma, and increasing or decreasing this front-to-rear difference accelerated or impeded soma advance. Thus, the tip of the leading process actively pulls the soma forward during neuronal migration through a myosin II-dependent forward F-actin flow along the leading process.
Local Neural Processing and the Generation of Dynamic Motor Commands within the Saccadic Premotor Network
Authors: Van Horn Marion R. , Mitchell Diana E. , Massot Corentin , Cullen Kathleen E.
Published: August 2010

The ability to accurately control movement requires the computation of a precise motor command. However, the computations that take place within premotor pathways to determine the dynamics of movements are not understood. Here we studied the local processing that generates dynamic motor commands by simultaneously recording spikes and local field potentials (LFPs) in the network that commands saccades. We first compared the information encoded by LFPs and spikes recorded from individual premotor and motoneurons (saccadic burst neurons, omnipause neurons, and motoneurons) in monkeys. LFP responses consistent with net depolarizations occurred in association with bursts of spiking activity when saccades were made in a neuron's preferred direction. In contrast, when saccades were made in a neuron's nonpreferred direction, neurons ceased spiking and the associated LFP responses were consistent with net hyperpolarizations. Surprisingly, hyperpolarizing and depolarizing LFPs encoded movement dynamics with equal robustness and accuracy. Second, we compared spiking responses at one hierarchical level of processing to LFPs at the next stage. Latencies and spike-triggered averages of LFP responses were consistent with each neuron's place within this circuit. LFPs reflected relatively local events (<500 μm) and encoded important features not available from the spiking train (i.e., hyperpolarizing response). Notably, quantification of their time-varying profiles revealed that a precise balance of depolarization and hyperpolarization underlies the production of precise saccadic eye movement commands at both motor and premotor levels. Overall, simultaneous recordings of LFPs and spiking responses provides an effective means for evaluating the local computations that take place to produce accurate motor commands.
Appetitive and Aversive Goal Values Are Encoded in the Medial Orbitofrontal Cortex at the Time of Decision Making
Authors: Plassmann Hilke , O'Doherty John P. , Rangel Antonio
Published: August 2010

An essential feature of choice is the assignment of goal values (GVs) to the different options under consideration at the time of decision making. This computation is done when choosing among appetitive and aversive items. Several groups have studied the location of GV computations for appetitive stimuli, but the problem of valuation in aversive contexts at the time of decision making has been ignored. Thus, although dissociations between appetitive and aversive components of value signals have been shown in other domains such as anticipatory and outcome values, it is not known whether appetitive and aversive GVs are computed in similar brain regions or in separate ones. We investigated this question using two different functional magnetic resonance imaging studies while human subjects placed real bids in an economic auction for the right to eat/avoid eating liked/disliked foods. We found that activity in a common area of the medial orbitofrontal cortex and the dorsolateral prefrontal cortex correlated with both appetitive and aversive GVs. These findings suggest that these regions might form part of a common network.
Synaptic Activity and Activity-Dependent Competition Regulates Axon Arbor Maturation, Growth Arrest, and Territory in the Retinotectal Projection
Authors: Fredj Naila Ben , Hammond Sarah , Otsuna Hideo , Chien Chi-Bin , Burrone Juan , Meyer Martin P.
Published: August 2010

In the retinotectal projection, synapses guide retinal ganglion cell (RGC) axon arbor growth by promoting branch formation and by selectively stabilizing branches. To ask whether presynaptic function is required for this dual role of synapses, we have suppressed presynaptic function in single RGCs using targeted expression of tetanus toxin light-chain fused to enhanced green fluorescent protein (TeNT-Lc:EGFP). Time-lapse imaging of singly silenced axons as they arborize in the tectum of zebrafish larvae shows that presynaptic function is not required for stabilizing branches or for generating an arbor of appropriate complexity. However, synaptic activity does regulate two distinct aspects of arbor development. First, single silenced axons fail to arrest formation of highly dynamic but short-lived filopodia that are a feature of immature axons. Second, single silenced axons fail to arrest growth of established branches and so occupy significantly larger territories in the tectum than active axons. However, if activity-suppressed axons had neighbors that were also silent, axonal arbors appeared normal in size. A similar reversal in phenotype was observed when single TeNT-Lc:EGFP axons are grown in the presence of the NMDA receptor antagonist MK801 [(+)-5-methyl-10,11- dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate]. Although expansion of arbor territory is prevented when neighbors are silent, formation of transient filopodia is not. These results suggest that synaptic activity by itself regulates filopodia formation regardless of activity in neighboring cells but that the ability to arrest growth and focusing of axonal arbors in the target is an activity-dependent, competitive process.
NADPH Oxidase-Dependent Regulation of T-Type Ca2+Channels and Ryanodine Receptors Mediate the Augmented Exocytosis of Catecholamines from Intermittent Hypoxia-Treated Neonatal Rat Chromaffin Cells
Authors: Souvannakitti Dangjai , Nanduri Jayasri , Yuan Guoxiang , Kumar Ganesh K. , Fox Aaron P. , Prabhakar Nanduri R.
Published: August 2010

Nearly 90% of premature infants experience the stress of intermittent hypoxia (IH) as a consequence of recurrent apneas (periodic cessation of breathing). In neonates, catecholamine secretion from the adrenal medulla is critical for maintaining homeostasis under hypoxic stress. We recently reported that IH treatment enhanced hypoxia-evoked catecholamine secretion and [Ca2+]iresponses in neonatal rat adrenal chromaffin cells and involves reactive oxygen species (ROS). The purpose of the present study was to identify the source(s) of ROS generation and examine the mechanisms underlying the enhanced catecholamine secretion by IH. Neonatal rats of either sex (postal day 0–5) were exposed to either IH or normoxia. IH treatment increased NADPH oxidase (NOX) activity, upregulated NOX2 and NOX4 transcription in adrenal medullae, and a NOX inhibitor prevented the effects of IH on hypoxia-evoked chromaffin cell secretion. IH upregulated Cav3.1 and Cav3.2 T-type Ca2+channel mRNAs via NOX/ROS signaling and augmented T-type Ca2+current in IH-treated chromaffin cells. Mibefradil, a blocker of T-type Ca2+channels attenuated the effects of hypoxia on [Ca2+]iand catecholamine secretion in IH-treated cells. In Ca2+-free medium, IH-treated cells exhibited higher basal [Ca2+]ilevels and more pronounced [Ca2+]iresponses to hypoxia compared with controls, and blockade of ryanodine receptors (RyRs) prevented these effects. RyR2 and RyR3 mRNAs were upregulated, RyR2 was S-glutathionylated in IH-treated adrenal medullae, and NOX/ROS inhibitors prevented these effects. These results demonstrate that neonatal IH treatment leads to NOX/ROS-dependent recruitment of T-type Ca2+channels and RyRs, resulting in augmented [Ca2+]imobilization and catecholamine secretion.
Describing the Brain in Autism in Five Dimensions—Magnetic Resonance Imaging-Assisted Diagnosis of Autism Spectrum Disorder Using a Multiparameter Classification Approach
Authors: Ecker Christine , Marquand Andre , Mourão-Miranda Janaina , Johnston Patrick , Daly Eileen M. , Brammer Michael J. , Maltezos Stefanos , Murphy Clodagh M. , Robertson Dene , Williams Steven C. , Murphy Declan G. M.
Published: August 2010

Autism spectrum disorder (ASD) is a neurodevelopmental condition with multiple causes, comorbid conditions, and a wide range in the type and severity of symptoms expressed by different individuals. This makes the neuroanatomy of autism inherently difficult to describe. Here, we demonstrate how a multiparameter classification approach can be used to characterize the complex and subtle structural pattern of gray matter anatomy implicated in adults with ASD, and to reveal spatially distributed patterns of discriminating regions for a variety of parameters describing brain anatomy. A set of five morphological parameters including volumetric and geometric features at each spatial location on the cortical surface was used to discriminate between people with ASD and controls using a support vector machine (SVM) analytic approach, and to find a spatially distributed pattern of regions with maximal classification weights. On the basis of these patterns, SVM was able to identify individuals with ASD at a sensitivity and specificity of up to 90% and 80%, respectively. However, the ability of individual cortical features to discriminate between groups was highly variable, and the discriminating patterns of regions varied across parameters. The classification was specific to ASD rather than neurodevelopmental conditions in general (e.g., attention deficit hyperactivity disorder). Our results confirm the hypothesis that the neuroanatomy of autism is truly multidimensional, and affects multiple and most likely independent cortical features. The spatial patterns detected using SVM may help further exploration of the specific genetic and neuropathological underpinnings of ASD, and provide new insights into the most likely multifactorial etiology of the condition.
Oral taste recognition in health volunteers
Authors: Costa Milton Melciades Barbosa , Santana Eliane , Almeida Juliana de
Published: August 2010

CONTEXT: Taste food recognition has an important role in the nutritional conditions and also allows protection of the organism integrity against foods potentially dangerous. OBJECTIVE: To investigate the presence of the selective taste regions on the tongue and also the palate participation in the oral taste definition. METHODS: A standard tongue divided in six regions was exposed with the four basic tastes (sweet, salted, sour and bitter), 10 times each. Thirteen volunteers were studied from both side and 34 only from one side, performing 240 tests with opened mouth and 240 with closing mouth, just after tongue sapid stimulation. A second group, with 12 volunteers, had its taste recognition studied, with and without palate isolation, using silicone prosthesis (n = 120). RESULTS: From results, chi-square (3×2) and (2×2), nonparametric independency test with P = 0.05 were obtained. CONCLUSIONS: Anterior, medium and posterior regions of the tongue, at both sides, had the same taste discriminative capacity. Nevertheless, closed mouth increased immediate and late recognition capacity by palate participation. It was possible to admit that palate participation increase the sapid perception in the mouth, by recruitment of the palate taste receptors and also by fluid compression and its scattering over tongue surface.
Clinical benefits after the implementation of a multimodal perioperative protocol in elderly patients
Authors: Aguilar-Nascimento José Eduardo de , Salomão Alberto Bicudo , Caporossi Cervantes , Diniz Breno Nadaf
Published: August 2010

CONTEXT: Multimodal protocol of perioperative care may enhance recovery after surgery. Based on evidence these new routines of perioperative care changed conventional prescriptions in surgery. OBJECTIVE: To evaluate the results of a multimodal protocol (ACERTO protocol) in elderly patients. METHODS: Non-randomized historical cohort study was performed at the surgical ward of a tertiary university hospital. One hundred seventeen patients aged 60 and older were submitted to elective abdominal operations under either conventional (n = 42; conventional group, January 2004-June 2005) or a fast-track perioperative protocol named ACERTO (n = 75; ACERTO group, July 2005-December 2007). Main endpoints were preoperative fasting time, postoperative day of re-feeding, volume of intravenous fluids, length of hospital stay and morbidity. RESULTS: The implantation of the ACERTO protocol was followed by a decrease in both preoperative fasting (15 [8-20] vs 4 [2-20] hours, P<0.001) and postoperative day of refeeding (1st [1st-10th] vs 0 [0-5th] PO day; P<0.01), and intravenous fluids (10.7 [2.5-57.5] vs 2.5 [0.5-82] L, P<0.001). The changing of protocols reduced the mean length of hospital stay by 4 days (6[1-43] vs 2[1-97] days; P = 0.002) and surgical site infection rate by 85.7% (19%; 8/42 vs 2.7%; 2/75, P<0.001; relative risk = 1.20; 95% confidence interval = 1.03-1.39). Per-protocol analysis showed that hospital stay in major operations diminished only in patients who completed the protocol (P<0.01). CONCLUSION: The implementation of multidisciplinary routines of the ACERTO protocol diminished both hospitalization and surgical site infection in elderly patients submitted to abdominal operations.
Treatment of inflammatory bowel disease and pregnancy: a review of the literature
Authors: Correia Lucianna Motta , Bonilha Danielle Queiroz , Ramos Juliana Dantas , Ambrogini Orlando , Miszputen Sender Jankiel
Published: August 2010

CONTEXT: The inflammatory bowel disease is diagnosed frequently among woman of childbearing capacity. The management must be carefully because there are potential risks for the mother and fetus. RESULTS AND CONCLUSIONS: We review literature about the management of inflammatory bowel disease in pregnancy. Some studies are needed to ensure the best approach to inflammatory bowel disease in pregnant women.
Turkey's Accession to the European Union in terms of impact on the EU's security and defense policies: potential and drawbacks
Authors: Pinto Maria do Céu
Published: August 2010

This study explores the impact of Turkey's likely entry in the European Union (EU) in terms of the EU's foreign, security and defense policies. It reviews Turkish capabilities, namely its military capabilities, which could provide the EU with valuable defense assets. There are differences related to Turkey's relations with the EU, which have increasingly spilled over into the NATO, hindering the development of cooperation over crisis management operations. The article then delves in the implications of Turkey's strategic geographical location to EU policies. It reviews how far the EU and Turkey may have convergent interests in some of the neighboring regions, especially in the Middle East.
Redemocratização e direitos humanos: a política para refugiados no Brasil
Authors: Moreira Julia Bertino
Published: August 2010

O presente trabalho analisa a política para refugiados no Brasil dos anos 1990 aos dias atuais. Diante do contexto internacional marcado pelos novos temas globais, dentre os quais direitos humanos e migrações forçadas, e do processo de redemocratização no plano doméstico, o tema dos refugiados foi tratado no país, atrelado aos direitos humanos.
Exportação de democracia na política externa norte-americana no pós-Guerra-Fria: doutrinas e o uso da força
Authors: Santos Maria Helena de Castro
Published: August 2010

O artigo analisa os pilares da política externa americana no pós-guerra fria, mirando o lugar que ai ocupa democracia e sua relação com segurança. Busca-se mais especificamente as bases da doutrina da política externa que justificam a exportação de democracia pelo uso da força. Utilizou-se a análise de conteúdo quantitativa e qualitativa de 415 discursos dos Presidentes e Secretários de Estado entre 1989 e 2008.
Avaliação histológica da próstata de cães adultos sexualmente intactos
Authors: Alves C.E. Fonseca , Faleiro M.B.R. , Amorim R. Laufer , De Moura V.M.B.D.
Published: August 2010

Avaliou-se histologicamente a próstata de 30 cães adultos e idosos sexualmente intactos que apresentavam ou não sintomatologia clínica de doença prostática, e verificou-se a incidência de possíveis alterações da glândula. Dentre as alterações encontradas, a hiperplasia prostática benigna constituiu o diagnóstico mais comum, 85,6% (n=24), seguida por prostatite crônica, 64,3% (n=18), displasia do epitélio glandular, 42,8% (n=12), atrofia do epitélio glandular, 39,3% (n=11), infiltrado inflamatório focal, 25% (n=7), dilatação glandular focal, 21,4% (n=6), prostatite aguda, 7,1% (n=2), metaplasia escamosa, 3,6%, (n=1), metástase de neoplasia sistêmica, 3,6% (n=1) e abscesso prostático, 3,6% (n=1). Como em muitos casos os cães são assintomáticos, ressalta-se a importância da realização rotineira de exames clínicos específicos, como o toque retal e a ultrassonografia, para o diagnóstico precoce e o tratamento das afecções prostáticas.
Qualidade espermática de sêmen de cães naturalmente infectados por Leishmania sp:
Authors: Labat É. , Carreira J.T. , Matsukuma B.H. , Martins M.T.A. , Lima V.M.F. , Bomfim S.R.M. , Perri S.H.V. , Koivisto M.B.
Published: August 2010

Avaliaram-se alterações espermáticas associadas à infecção por leishmaniose no sêmen de cães naturalmente infectados, utilizando-se, durante oito semanas consecutivas, ejaculados de seis cães soronegativos e seis cães soropositivos. As amostras foram colhidas uma vez por semana e avaliadas quanto ao volume, concentração, motilidade, vigor, morfologia espermática, integridade da cromatina, avaliação simultânea da integridade da membrana plasmática, acrossoma e potencial mitocondrial. Concomitantemente foram dosadas a proteína total do plasma seminal e sanguíneo. A leishmaniose visceral causou aumento dos defeitos maiores e menores nos espermatozoides dos animais acometidos pelo estágio moderado a severo da doença. Em estágios mais avançados da enfermidade, a integridade das membranas acrossomal e plasmática foi afetada negativamente. Não foi possível estabelecer um critério quanto à avaliação do potencial mitocondrial. A incidência de alterações morfológicas nos animais acometidos não promoveu aumento de injurias à cromatina. Todos os animais com leishmaniose apresentaram hiperproteinemia do sêmen.
Suplementação de betaglucano a dietas de leitões de 21 a 60 dias de idade
Authors: Mendes C.B.S. , Fontes D.O. , Guedes R.M.C. , Silva F.C.O. , Silva M.A. , Oliveira J.S.V. , Fernandes I.S. , Fontes F.A.P.V.
Published: August 2010

Realizou-se um experimento com 1.500 leitões distribuídos em delineamento experimental de blocos ao acaso com cinco tratamentos: controle e com suplementação de 60, 120, 180 e 240g de betaglucano por tonelada de dieta. Foram analisadas as variáveis ganho de peso diário, peso final, consumo de dieta diário e conversão alimentar nos períodos de 21 a 35, 21 a 49 e 21 a 60 dias de idade. Houve aumento linear significativo do peso final e do ganho de peso diário de leitões suplementados com betaglucano na dieta dos 21 aos 60 dias de idade. A inclusão de 240g/ton. proporcionou aumento no peso final de 800g, o que corresponde ao aumento de 3,2% em relação aos animais do grupo-controle. O ganho de peso diário foi 4,7% mais alto para o grupo de animais tratados com 240g/ton. Não se observou efeito significativo dos tratamentos sobre: consumo diário de dieta, conversão alimentar, atividade da enzima superóxido dismutase nem sobre a resposta imune.
Fontes de lipídios na dieta de poedeiras: desempenho produtivo e qualidade dos ovos
Authors: Oliveira D.D. , Baião N.C. , Cançado S.V. , Figueiredo T.C. , Lara L.J.C. , Lana A.M.Q.
Published: August 2010

Os efeitos de fontes de lipídios na dieta de poedeiras sobre o desempenho produtivo e a qualidade do ovo foram verificados em dois experimentos. Foram utilizados quatro tratamentos, definidos de acordo com a fonte lipídica adicionada nas rações: óleo de soja, óleo de girassol, óleo de linhaça e ração controle (sem adição de óleo). Os experimentos foram realizados com poedeiras de 20 e 54 semanas de idade, respectivamente, com duração de oito semanas. Avaliaram-se os parâmetros produtivos - consumo de ração, conversão alimentar, produção e peso dos ovos - e de qualidade do ovo - porcentagens de gema, albúmen e casca, sólidos da gema, unidades Haugh, pH do albúmen, e cor da gema. Somente o peso do ovo de poedeiras jovens foi afetado pela inclusão de óleos vegetais na ração. Esses ovos apresentaram maior peso e maior porcentagem de gema que os produzidos pelas poedeiras jovens alimentadas com ração-controle. Concluiu-se que a utilização de diferentes fontes de lipídios na ração de poedeiras não altera o desempenho produtivo e a qualidade interna dos ovos, com exceção do peso do ovo de poedeiras novas, que aumenta com a utilização de óleos vegetais.