bluuebunny/crossref_metadata_2025 huggingface dataset:
Changing Microcircuits in the Subplate of the Developing Cortex
Authors: Viswanathan Sarada , Bandyopadhyay Sharba , Kao Joseph P. Y. , Kanold Patrick O.
Published: February 2012

Subplate neurons (SPNs) are a population of neurons in the mammalian cerebral cortex that exist predominantly in the prenatal and early postnatal period. Loss of SPNs prevents the functional maturation of the cerebral cortex. SPNs receive subcortical input from the thalamus and relay this information to the developing cortical plate and thereby can influence cortical activity in a feedforward manner. Little is known about potential feedback projections from the cortical plate to SPNs. Thus, we investigated the spatial distribution of intracortical synaptic inputs to SPNsin vitroin mouse auditory cortex by photostimulation. We find that SPNs fell into two broad classes based on their distinct spatial patterns of synaptic inputs. The first class of SPNs receives inputs from only deep cortical layers, while the second class of SPNs receives inputs from deep as well as superficial layers including layer 4. We find that superficial cortical inputs to SPNs emerge in the second postnatal week and that SPNs that receive superficial cortical input are located more superficially than those that do not. Our data thus suggest that distinct circuits are present in the subplate and that, while SPNs participate in an early feedforward circuit, they are also involved in a feedback circuit at older ages. Together, our results show that SPNs are tightly integrated into the developing thalamocortical and intracortical circuit. The feedback projections from the cortical plate might enable SPNs to amplify thalamic inputs to SPNs.
Arrest of Myelination and Reduced Axon Growth When Schwann Cells Lack mTOR
Authors: Sherman Diane L. , Krols Michiel , Wu Lai-Man N. , Grove Matthew , Nave Klaus-Armin , Gangloff Yann-Gaël , Brophy Peter J.
Published: February 2012

In developing peripheral nerves, differentiating Schwann cells sort individual axons from bundles and ensheath them to generate multiple layers of myelin. In recent years, there has been an increased understanding of the extracellular and intracellular factors that initiate and stimulate Schwann cell myelination, together with a growing appreciation of some of the signaling pathways involved. However, our knowledge of how Schwann cell growth is regulated during myelination is still incomplete. The mammalian target of rapamycin (mTOR) is a core kinase in two major complexes, mTORC1 and mTORC2, that regulate cell growth and differentiation in a variety of mammalian cells. Here we show that elimination of mTOR from murine Schwann cells prevented neither radial sorting nor the initiation of myelination. However, normal postnatal growth of myelinating Schwann cells, both radially and longitudinally, was highly retarded. The myelin sheath in the mutant was much thinner than normal; nevertheless, sheath thickness relative to axon diameter (g-ratio) remained constant in both wild-type and mutant nerves from P14 to P90. Although axon diameters were normal in the mutant at the initiation of myelination, further growth as myelination proceeded was retarded, and this was associated with reduced phosphorylation of neurofilaments. Consistent with thinner axonal diameters and internodal lengths, conduction velocities in mutant quadriceps nerves were also reduced. These data establish a critical role for mTOR signaling in both the longitudinal and radial growth of the myelinating Schwann cell.
Bimodal Optomotor Response to Plaids in Blowflies: Mechanisms of Component Selectivity and Evidence for Pattern Selectivity
Authors: Saleem Aman B. , Longden Kit D. , Schwyn Daniel A. , Krapp Holger G. , Schultz Simon R.
Published: February 2012

Many animals estimate their self-motion and the movement of external objects by exploiting panoramic patterns of visual motion. To probe how visual systems process compound motion patterns, superimposed visual gratings moving in different directions, plaid stimuli, have been successfully used in vertebrates. Surprisingly, nothing is known about how visually guided insects process plaids. Here, we explored in the blowfly how the well characterized yaw optomotor reflex and the activity of identified visual interneurons depend on plaid stimuli. We show that contrary to previous expectations, the yaw optomotor reflex shows a bimodal directional tuning for certain plaid stimuli. To understand the neural correlates of this behavior, we recorded the responses of a visual interneuron supporting the reflex, the H1 cell, which was also bimodally tuned to the plaid direction. Using a computational model, we identified the essential neural processing steps required to capture the observed response properties. These processing steps have functional parallels with mechanisms found in the primate visual system, despite different biophysical implementations. By characterizing other visual neurons supporting visually guided behaviors, we found responses that ranged from being bimodally tuned to the stimulus direction (component-selective), to responses that appear to be tuned to the direction of the global pattern (pattern-selective). Our results extend the current understanding of neural mechanisms of motion processing in insects, and indicate that the fly employs a wider range of behavioral responses to multiple motion cues than previously reported.
Neuronal Responses in the Nucleus Accumbens Shell during Sexual Behavior in Male Rats
Authors: Matsumoto Jumpei , Urakawa Susumu , Hori Etsuro , de Araujo Mariana F. P. , Sakuma Yasuo , Ono Taketoshi , Nishijo Hisao
Published: February 2012

Previous behavioral studies have indicated that the nucleus accumbens (NAc) shell of a male rat is involved in its sexual behavior; however, no previous studies have investigated neuronal activities in the male rat NAc shell during sexual behavior. To investigate this issue, we recorded single unit activities in the NAc shell of male rats during sexual behavior. Of 123 NAc shell neurons studied, 53, 47, and 40 neurons exhibited significantly changed firing rates at various times during intromission, genital auto-grooming, and sniffing of females, respectively. The two types of NAc shell neurons [putative fast spiking interneurons (pFSIs) and medium spiny neurons (pMSNs)] responded differently during sexual behavior. First, more pFSIs than pMSNs exhibited inhibitory responses to thrusting with intromission and genital grooming, while pFSIs and pMSNs responded similarly to sniffing of females. Second, both pFSIs and pMSNs responded differently to thrusting with and without intromission. Furthermore, NAc shell neuronal activity was significantly different across the different phases of sexual behavior, and the number of NAc shell neurons with delta oscillation, which is related to behavioral inhibition, and high gamma oscillation, which is related to reward perception, increased after ejaculation. Together, our results suggest that the NAc shell is deeply involved in sexual behavior, and changes in NAc shell neuronal activity are related to performance of sexual behavior, encoding cues or contexts related to sexual behavior, reward-related processing, and the inhibition of sexual behavior after ejaculation.
Neuronal Glutamate Transporters Regulate Glial Excitatory Transmission
Authors: Tsai Ming-Chi , Tanaka Kohichi , Overstreet-Wadiche Linda , Wadiche Jacques I.
Published: February 2012

In the CNS, excitatory amino acid transporters (EAATs) localized to neurons and glia terminate the actions of synaptically released glutamate. Whereas glial transporters are primarily responsible for maintaining low ambient levels of extracellular glutamate, neuronal transporters have additional roles in shaping excitatory synaptic transmission. Here we test the hypothesis that the expression level of the Purkinje cell (PC)-specific transporter, EAAT4, near parallel fiber (PF) release sites controls the extrasynaptic glutamate concentration transient following synaptic stimulation. Expression of EAAT4 follows a parasagittal banding pattern that allows us to compare regions of high and low EAAT4-expressing PCs. Using EAAT4 promoter-driven eGFP reporter mice together with pharmacology and genetic deletion, we show that the level of neuronal transporter expression influences extrasynaptic transmission from PFs to adjacent Bergmann glia (BG). Surprisingly, a twofold difference in functional EAAT4 levels is sufficient to alter signaling to BG, although EAAT4 may only be responsible for removing a fraction of released glutamate. These results demonstrate that physiological regulation of neuronal transporter expression can alter extrasynaptic neuroglial signaling.
Astrocytes Control the Development of the Migration-Promoting Vasculature Scaffold in the Postnatal Brain via VEGF Signaling
Authors: Bozoyan Lusine , Khlghatyan Jivan , Saghatelyan Armen
Published: February 2012

New neurons are constantly being generated in the postnatal subventricular zone. They have to migrate long distances via the rostral migratory stream (RMS) to reach their final destination in the olfactory bulb (OB). In adults, these neuronal precursors migrate in chains, ensheathed by astrocytic processes, and travel toward the OB along blood vessels (BVs) that topographically outline the RMS. The molecular and cellular mechanisms leading to the development of the RMS and the formation of the migration-promoting vasculature scaffold in the adult mice remain unclear. We now reveal that astrocytes orchestrate the formation and structural reorganization of the vasculature scaffold in the RMS and, during early developmental stages, the RMS contains only a few BVs oriented randomly with respect to the migrating neuroblasts. The first parallel BVs appeared at the outer border of the RMS, where vascular endothelial growth factor (VEGF)-expressing astrocytes are located. Gain-of-function and loss-of-function experiments revealed that astrocyte-derived VEGF plays a crucial role in the formation and growth of new BVs. Real-time videoimaging also showed that the migration of neuronal precursors in the developing RMS differs substantially from neuronal displacement in the adult migratory stream partially because of not yet fully developed vasculature scaffold. The downregulation of VEGFin vivo, specifically in the astrocytes of the developing RMS, affected the development of the vasculature scaffold and led to alterations in neuroblast migration. Altogether, our results demonstrate that astrocytes orchestrate the formation and growth of parallel BVs, crucial migration-promoting scaffolds in the adult migratory stream, via VEGF signaling.
LRRK2 Inhibition Attenuates Microglial Inflammatory Responses
Authors: Moehle Mark S. , Webber Philip J. , Tse Tonia , Sukar Nour , Standaert David G. , DeSilva Tara M. , Cowell Rita M. , West Andrew B.
Published: February 2012

Missense mutations inleucine-rich repeat kinase 2 (LRRK2)cause late-onset Parkinson's disease (PD), and common genetic variation inLRRK2modifies susceptibility to Crohn's disease and leprosy. High levels of LRRK2 expression in peripheral monocytes and macrophages suggest a role for LRRK2 in these cells, yet little is known about LRRK2 expression and function in immune cells of the brain. Here, we demonstrate a role for LRRK2 in mediating microglial proinflammatory responses and morphology. In a murine model of neuroinflammation, we observe robust induction of LRRK2 in microglia. Experiments with toll-like receptor 4 (TLR4)-stimulated rat primary microglia show that inflammation increases LRRK2 activity and expression, while inhibition of LRRK2 kinase activity or knockdown of protein attenuates TNFα secretion and nitric oxide synthase (iNOS) induction. LRRK2 inhibition blocks TLR4 stimulated microglial process outgrowth and impairs ADP stimulated microglial chemotaxis. However, actin inhibitors that phenocopy inhibition of process outgrowth and chemotaxis fail to modify TLR4 stimulation of TNFα secretion and inducible iNOS induction, suggesting that LRRK2 acts upstream of cytoskeleton control as a stress-responsive kinase. These data demonstrate LRRK2 in regulating responses in immune cells of the brain and further implicate microglial involvement in late-onset PD.
Monologue Conflicts: The Terms of Operatic Criticism in Pierre Estève and Jean-Jacques Rousseau
Authors: Stevens Blake
Published: February 2012

Jean-Jacques Rousseau's entry for “monologue” in his Dictionnaire de musique (1767) marks the first appearance of the term in French musical lexicography. This definition, which would exert an influence on later discussion of the form, synthesizes principles drawn from poetics and dramaturgy with stylistic arguments developed during the Querelle des Bouffons. The entry powerfully and succinctly conveys an Italianate conception of the form by promoting an idiom (récitatif obligé) associated with Italian practice as the exemplary realization of monologic discourse. This essay places Rousseau's account in the context of French criticism from Le Cerf de la Viéville, writing early in the eigtheenth century, to Pierre Estève, writing in the early 1750s. Treatment of the monologue at mid-century attests not only to a critical interest in exemplary scenes, particularly the famous monologue from Armide, “Enfin il est en ma puissance,” but also to readings of monologues as markers of national musical style. Against Rousseau's identification of monologue with récitatif obligé stands the more pluralistic model of Estève, who described a range of vocal idioms linked to dramatic context and meaning. Moreover, Estève attempted to account not only for newer works of Rameau but also for revivals of the tragédies en musique of Lully and Campra. Consideration of Estève's examples of characteristic scenes illustrates a tendency to equate monologic discourse with effects of interruption and the suspension of dialogue, even when other characters are present onstage.
Reading a Relationship: Solo-Tutti Interaction and Dramatic Trajectory in Beethoven's Second Piano Concerto
Authors: Tusa Michael C.
Published: February 2012

The evolving relationship between the solo and the tutti over the course of Beethoven's Piano Concerto No. 2 in B♭ major, op. 19, contributes to its individuality as a piece of music and provides clues for understanding its significance for Beethoven's early career. A structural analysis of solo-tutti interaction reveals a double trajectory spanning the concerto, one leading from relative opposition between the protagonists to proximity or agreement, and the other from the leadership of the tutti to that of the soloist. The extant sources of the protracted genesis of the concerto provide evidence for how Beethoven may have contemplated alternative enactments of the solo-tutti relationship in the first movement and suggest reasons behind his decision to replace the early (if not in fact original) conclusion to the concerto, the Rondo in B♭ major WoO 6, with the definitive finale of op. 19. The essay concludes with some thoughts on the implications of the solo-tutti relationship in op. 19 for the ways that the young Beethoven positioned himself within Viennese society and its musical heritage.
Characterization of multiple first exons in murine prolactin receptor gene and the effect of prolactin on their expression in the choroid plexus
Authors: Tabata Hidemi , Kobayashi Momoko , Ikeda Junko H , Nakao Nobuhiro , Saito Toru R , Tanaka Minoru
Published: February 2012

Prolactin (Prl) receptor (Prlr) gene is expressed in various brain regions, with the highest level present in the choroid plexus, a site for receptor-mediated PRL transport from the blood to cerebrospinal fluid. We investigated the regulatory mechanism ofPrlrgene expression by PRL in the murine choroid plexus. We first examined the organization of the alternative first exons in murinePrlrgene. In addition to the three known first exons, mE11, mE12, and mE13, two first exons, mE14and mE15, were newly identified by cDNA cloning. Each first exon variant ofPrlrmRNA exhibited tissue-specific or generic expression. In the choroid plexus of mice, the expression levels ofmE13-,mE14-, andmE15-PrlrmRNAs were increased in the lactating mice compared with those in the diestrus mice. Furthermore, the expression level ofmE14-PrlrmRNA was decreased in the PRL-deficient (Prl−/−) mice compared with the PRL-normal (Prl+/+andPrl+/−) mice. In the ovariectomizedPrl−/−mice, the expression level ofmE14-PrlrmRNA was significantly increased by PRL administration but not by 17β-estradiol administration. The expression levels of the two last exon variants ofPrlrmRNAs, encoding the long and short cytoplasmic regions of PRLR, were also increased in the lactating mice and decreased in thePrl−/−mice. These findings suggest that PRL stimulates thePrlrgene expression through the transcriptional activation of mE14first exon, leading to increases in the long- and short-form variants ofPrlrmRNA in the murine choroid plexus.
Understanding and Predicting the Fitness Decline of Shrunk Populations: Inbreeding, Purging, Mutation, and Standard Selection
Authors: García-Dorado Aurora
Published: February 2012

The joint consequences of inbreeding, natural selection, and deleterious mutation on mean fitness after population shrinkage are of great importance in evolution and can be critical to the conservation of endangered populations. I present simple analytical equations that predict these consequences, improving and extending a previous heuristic treatment. Purge is defined as the “extra” selection induced by inbreeding, due to the “extra” fitness disadvantage (2d) of homozygotes for (partially) recessive deleterious alleles. Its effect is accounted for by using, instead of the classical inbreeding coefficient f, a purged inbreeding coefficient g that is weighed by the reduction of the frequency of deleterious alleles caused by purging. When the effective size of a large population is reduced to a smaller stable value N (with Nd ≥ 1), the purged inbreeding coefficient after t generations can be predicted as gt ≈ [(1 – 1/2N) gt-1 + 1/2N](1 – 2d ft-1), showing how purging acts upon previously accumulated inbreeding and how its efficiency increases with N. This implies an early fitness decay, followed by some recovery. During this process, the inbreeding depression rate shifts from its ancestral value (δ) to that of the mutation–selection–drift balance corresponding to N (δ*), and standard selection cancels out the inbreeding depression ascribed to δ*. Therefore, purge and inbreeding operate only upon the remaining δ − δ*. The method is applied to the conservation strategy in which family contributions to the breeding pool are equal and is extended to make use of genealogical information. All these predictions are checked using computer simulation.
Neural Maintenance Roles for the Matrix Receptor Dystroglycan and the Nuclear Anchorage Complex in Caenorhabditis elegans
Authors: Johnson Robert P , Kramer James M
Published: February 2012

Recent studies in Caenorhabditis elegans have revealed specific neural maintenance mechanisms that protect soma and neurites against mispositioning due to displacement stresses, such as muscle contraction. We report that C. elegans dystroglycan (DG) DGN-1 functions to maintain the position of lumbar neurons during late embryonic and larval development. In the absence of DGN-1 the cell bodies of multiple lumbar neuron classes are frequently displaced anterior of their normal positions. Early but not later embryonic panneural expression of DGN-1 rescues positional maintenance, suggesting that dystroglycan is required for establishment of a critical maintenance pathway that persists throughout later developmental stages. Lumbar neural maintenance requires only a membrane-tethered N-terminal domain of DGN-1 and may involve a novel extracellular partner for dystroglycan. A genetic screen for similar lumbar maintenance mutants revealed a role for the nesprin/SYNE family protein ANC-1 as well as for the extracellular protein DIG-1, previously implicated in lumbar neuron maintenance. The involvement of ANC-1 reveals a previously unknown role for nucleus–cytoskeleton interactions in neural maintenance. Genetic analysis indicates that lumbar neuron position is maintained in late embryos by parallel DGN-1/DIG-1 and ANC-1–dependent pathways, and in larvae by separate DGN-1 and ANC-1 pathways. The effect of muscle paralysis on late embryonic- or larval-stage maintenance defects in mutants indicates that lumbar neurons are subject to both muscle contraction-dependent and contraction-independent displacement stresses, and that different maintenance pathways may protect against specific types of displacement stress.
A Test for Selection Employing Quantitative Trait Locus and Mutation Accumulation Data
Authors: Rice Daniel P , Townsend Jeffrey P
Published: February 2012

Evolutionary biologists attribute much of the phenotypic diversity observed in nature to the action of natural selection. However, for many phenotypic traits, especially quantitative phenotypic traits, it has been challenging to test for the historical action of selection. An important challenge for biologists studying quantitative traits, therefore, is to distinguish between traits that have evolved under the influence of strong selection and those that have evolved neutrally. Most existing tests for selection employ molecular data, but selection also leaves a mark on the genetic architecture underlying a trait. In particular, the distribution of quantitative trait locus (QTL) effect sizes and the distribution of mutational effects together provide information regarding the history of selection. Despite the increasing availability of QTL and mutation accumulation data, such data have not yet been effectively exploited for this purpose. We present a model of the evolution of QTL and employ it to formulate a test for historical selection. To provide a baseline for neutral evolution of the trait, we estimate the distribution of mutational effects from mutation accumulation experiments. We then apply a maximum-likelihood-based method of inference to estimate the range of selection strengths under which such a distribution of mutations could generate the observed QTL. Our test thus represents the first integration of population genetic theory and QTL data to measure the historical influence of selection.
TORC2 Signaling Is Antagonized by Protein Phosphatase 2A and the Far Complex in Saccharomyces cerevisiae
Authors: Pracheil Tammy , Thornton Janet , Liu Zhengchang
Published: February 2012

The target of rapamycin (TOR) kinase, a central regulator of eukaryotic cell growth, exists in two essential, yet distinct, TOR kinase complexes in the budding yeast Saccharomyces cerevisiae: rapamycin-sensitive TORC1 and rapamycin-insensitive TORC2. Lst8, a component of both TOR complexes, is essential for cell viability. However, it is unclear whether the essential function of Lst8 is linked to TORC1, TORC2, or both. To that end, we carried out a genetic screen to isolate lst8 deletion suppressor mutants. Here we report that mutations in SAC7 and FAR11 suppress lethality of lst8Δ and TORC2-deficient (tor2-21) mutations but not TORC1 inactivation, suggesting that the essential function of Lst8 is linked only to TORC2. More importantly, characterization of lst8Δ bypass mutants reveals a role for protein phosphatase 2A (PP2A) in the regulation of TORC2 signaling. We show that Far11, a member of the Far3-7-8-9-10-11 complex involved in pheromone-induced cell cycle arrest, interacts with Tpd3 and Pph21, conserved components of PP2A, and deletions of components of the Far3-7-8-9-10-11 complex and PP2A rescue growth defects in lst8Δ and tor2-21 mutants. In addition, loss of the regulatory B′ subunit of PP2A Rts1 or Far11 restores phosphorylation to the TORC2 substrate Slm1 in a tor2-21 mutant. Mammalian Far11 orthologs FAM40A/B exist in a complex with PP2A known as STRIPAK, suggesting a conserved functional association of PP2A and Far11. Antagonism of TORC2 signaling by PP2A-Far11 represents a novel regulatory mechanism for controlling spatial cell growth of yeast.
Mortality rates due to amyotrophic lateral sclerosis in São Paulo City from 2002 to 2006
Authors: Matos Sheila Evangelista de , Conde Mônica Tilli Reis Pessoa , Fávero Francis Meire , Taniguchi Mauro , Quadros Abrahão Augusto Juviniano , Fontes Sissy Veloso , Oliveira Acary Souza Bulle
Published: February 2012

OBJECTIVE: To describe the mortality rates of amyotrophic lateral sclerosis (ALS) in the city of São Paulo as a function of demographics, year, and region. METHOD: This was a retrospective descriptive study. Information was obtained from death certificates registered at the Program for the Improvement of Mortality Information, Municipal Health Department (PRO-AIM/SMS), coded as G12.2 according to International Classification of Diseases (ICD-10), from 2002 to 2006. RESULTS: Over the studied time, were found 326 deaths (51.6% women, overall mean age of 64.1 years). Highest deaths percentages happened in those from 60 to 69 and 70 to 79 years and in white individuals. ALS mortality rates ranged 0.44/100,000 in 2002 and 0.76/100,000 in 2006. No significant changes overtime in administrative districts were found. CONCLUSION: ALS mortality rates in São Paulo were lower in comparison to other countries, however any risk factor in our environment, lifestyle or genetic characteristics were found.
Epidemiology of amyotrophic lateral sclerosis patients in a centre in Buenos Aires
Authors: Bettini Mariela , Gargiulo-Monachelli Gisella M. , Rodríguez Gabriel , Rey Raul C. , Peralta Liliana Martinez , Sica Roberto E.P.
Published: February 2012

Sporadic amyotrophic lateral sclerosis (sALS) is considered a multifactorial disease with genetic and environmental factors causing motor neuron degeneration. OBJECTIVE: To describe the epidemiological and occupational characteristics of patients with sALS who attended the Ramos Mejía Hospital at Buenos Aires, Argentina. METHOD: We analyzed the medical records of sALS patients diagnosed between 2001 and 2008. All occupations were coded according to the International Standard Classification of Occupation (ISCO). RESULTS: 187 patients were assessed, 38.5% were women and 61.5% men. Mean age at diagnosis was 55 years. 16% of them came from rural areas; 68% of the studied population had no health insurance. 40% were employed in elementary occupations, 19 were technicians and 8 handicraftsmen. CONCLUSION: The most represented profession was elementary occupation. A large proportion of patients came from rural areas, which might suggest an increased risk of environmental exposure to an unknown agent in those regions.
Neuroimaging in stroke and non-stroke pusher patients
Authors: Santos-Pontelli Taiza Elaine Grespan , Pontes-Neto Octavio Marques , Araujo Draulio Barros de , Santos Antonio Carlos dos , Leite João Pereira
Published: February 2012

Pusher behavior (PB) is a disorder of postural control affecting patients with encephalic lesions. This study has aimed to identify the brain substrates that are critical for the occurrence of PB, to analyze the influence of the midline shift (MS) and hemorrhagic stroke volume (HSV) on the severity and prognosis of the PB. We identified 31 pusher patients of a neurological unit, mean age 67.4±11.89, 61.3% male. Additional neurological and functional examinations were assessed. Neuroimaging workup included measurement of the MS, the HSV in patients with hemorrhagic stroke, the analysis of the vascular territory, etiology and side of the lesion. Lesions in the parietal region (p=0.041) and thalamus (p=0.001) were significantly more frequent in PB patients. Neither the MS nor the HSV were correlated with the PB severity or recovery time.
Thermal record of the test tubes method used for small fibers assessment
Authors: Collina Denny D. , Villarroel Manoel F. , Tierra-Criollo Carlos Julio
Published: February 2012

In Brazil, the test that uses test tubes filled with cold water (25ºC) and tubes filled with water heated to a temperature of 45ºC is recommended by the Ministry of Health as a way of evaluate thermal sensitivity on the injured skin of leprosy patients. The purpose of this work was to quantify the thermal stimulation applied to the skin, as well as the temperature variation of the heated water and of the tube's outer surface during stimulation sessions. The experiment had the participation of 14 healthy volunteers (31.2±11.4 years-old), ten of which were male (33.1±13.5 years-old) and four were female (26.5±4.7 years-old). Three consecutive stimulation sessions were carried out, each of them with four stimuli. The maximum skin temperature at the end of the stimuli was measured at 35.8±0.6ºC. Such temperature values may be useful in the assessment of the loss of small fibers, which are responsible for the sensation of warmth.
Behavioral investigation of mice with experimental autoimmune encephalomyelitis
Authors: Rodrigues David Henrique , Vilela Márcia de Carvalho , Lacerda-Queiroz Norinne , Miranda Aline Silva de , Sousa Larissa Fonseca da Cunha , Reis Helton José dos , Teixeira Antônio Lúcio
Published: February 2012

Multiple sclerosis is a neuroinflammatory disease that results in serious neurological disability. Besides physical impairment, behavioral symptoms are also common in patients with multiple sclerosis. Experimental autoimmune encephalomyelitis (EAE) is considered to be a model of multiple sclerosis and mimics the main features of the disease, such as demyelination and motor impairment. In this work, we aimed to study behavioral parameters in animals with EAE using the MOG35-55 model in C57BL/6 mice. We analyzed memory and anxiety in animals using the elevated plus maze, the step down inhibitory avoidance task and the memory recognition test. No differences in any tests were found when comparing controls and animals induced with EAE. Therefore, we conclude that behavioral changes in animals with EAE induced with MOG35-55 are probably subtle or absent.
Validation of a Brazilian quantitative sensory testing (QST) device for the diagnosis of small fiber neuropathies
Authors: Schestatsky Pedro , Stefani Luciana Cadore , Sanches Paulo Roberto , Silva Júnior Danton Pereira da , Torres Iraci Lucena Silva , Dall-Agnol Letizzia , Balbinot Luciane Fachin , Caumo Wolnei
Published: February 2012

Quantitative sensory testing (QST) is defined as the determination of thresholds for sensory perception under controlled stimulus. Our aim was to validate a new QST device for Brazilian sample. In 20 healthy adults, thermoalgesic thresholds were assessed using a QST prototype (Heat Pain Stimulator-1.1.10; Brazil). A 30 × 30 mm² thermode with a 1°C/s stimulus change rate were applied. Thresholds of three consecutive stimuli were averaged in two different sessions separated by at least two weeks. Additionally long thermal heat pain stimulus was performed. To evaluate the consistency of our method we also analyzed 11 patients with small fiber neuropathy. Results showed good reproducibility of thermal perception thresholds in normal individuals and plausible abnormal thresholds in patients. We conclude that our QST device is reliable when analyzing the nociceptive pathway in controls and patients.
Rethinking the neurological examination I: static balance assessment
Authors: Maranhão-Filho Péricles A. , Maranhão Eliana Teixeira , Silva Marcos Martins da , Lima Marco Antônio
Published: February 2012

The authors advocate a modernization of the neurologic exam with regard to the evaluation of static equilibrium through the application of some easily performed and interpreted bedside maneuvers like the Clinical Test of Sensory Integration and Balance - modified and the Functional Reach Test. The authors also believe that these and other assessments, such as that of the risk of falling for elderly patients, should be incorporated into the routine neurological examination.
Desenvolvimento dos biocombustíveis no Brasil e no Leste Asiático: experiências e desafios
Authors: Masiero Gilmar
Published: February 2012

Este artigo resume o papel que as novas tecnologias e as políticas governamentais têm desempenhado na evolução da indústria dos biocombustíveis no Brasil e no Leste Asiático. Ele documenta os fatores que contribuíram para que o Brasil, China, Japão e Coreia do Sul se tornassem produtores e consumidores de biocombustíveis, bem como a extensão em que essa fonte de energia tem sido efetivamente adotada em cada uma dessas economias. Em seguida, avalia a extensão do comércio e da cooperação em biocombustíveis entre os três países do Leste Asiático e o Brasil. Argumenta que o Japão é muito mais avançado em sua cooperação sobre biocombustíveis com o Brasil e que nas demais economias asiáticas existe grande potencial para maior cooperação.
O Relatório Meltzer de 2000 e a reforma do Banco Mundial e do FMI
Authors: Pereira João Márcio Mendes
Published: February 2012

O artigo discute as propostas do Relatório Meltzer para a reforma do Banco Mundial e do Fundo Monetário Internacional. Esse relatório resultou do trabalho realizado entre 1998 e 2000 por uma comissão do Congresso americano. Discute também a resposta do Tesouro americano àquelas propostas e mostra como algumas delas foram implementadas seletivamente pelo governo de George W. Bush.
Brasil y la región: una potencia emergente y la integración regional sudamericana
Authors: Santos Sergio Caballero
Published: February 2012

En los últimos años, Brasil se está convirtiendo en una potencia mundial, a la vez que se le considera el líder regional. En este trabajo se aborda el papel creciente de Brasil en el ámbito internacional, al tiempo que aumentan las tensiones con sus vecinos. ¿Cuál es la prioridad de la política exterior brasileña: las relaciones regionales o los asuntos mundiales?
Promessa tecnológica e vantagem combatente
Authors: Proença Júnior Domício
Published: February 2012

Para compreender como se vai desde promessas tecnológicas presentes ou futuras até a disponibilidade, pronta e concreta, de vantagem combatente, este artigo enquadra tal processo como a articulação da lógica política com a gramática dos meios de força. Apresenta-se uma ilustração histórica que busca trazer à mente algumas coisas sobre as quais se pensar.
Brazil and the institutionalization of South America: from hemispheric estrangement to cooperative hegemony
Authors: Teixeira Carlos Gustavo Poggio
Published: February 2012

This article argues that Brazil went from a posture of estrangement in relation to the hemispheric project represented by the Free Trade Area of the Americas (FTAA) to a strategy of cooperative hegemony aimed at institutionalizing the South American space and increasing the costs of the FTAA for the United States. Although Brazil was initially isolated, US lack of leadership combined with events at the subregional level ended up turning the tide in the direction of Brazilian interests. These factors help to understand the current institutional configuration of South America.
Instituições e grupos de interesse: a União Europeia nas negociações agrícolas da Rodada Doha (2001-2005)
Authors: Carvalho Maria Izabel Valladão de
Published: February 2012

Este artigo aborda a influência dos grupos de interesse dos produtores rurais nas posições adotadas pela UE durante a Rodada Doha. As propostas defendidas pelos dois atores foram comparadas e analisadas. Argumenta-se que as diferenças de posições encontradas podem ser explicadas pelas regras institucionais do processo decisório da Política Comercial Comum da UE. A conclusão destaca que as pressões dos grupos de interesse afetaram parcialmente as posturas da UE na Rodada Doha e não impediram que avanços se efetivassem nesse contexto.
Growth, nodulation and nitrogen fixation of cowpea in soils amended with composted tannery sludge
Authors: Santos Joseany Andrade , Nunes Luís Alfredo Pinheiro Leal , Melo Wanderley José de , Figueiredo Marcia Barreto do Vale , Singh Rajeev Pratap , Bezerra Antônio Aécio Carvalho , Araújo Ademir Sérgio Ferreira de
Published: February 2012

Tannery wastes generation is increasing every year and a suitable method for tannery sludge management is necessary in order to decrease this environmental problem. The composting is recognized as a suitable method for sludge recycling.. The effect of tannery sludge compost (TSC) rates on growth, nodulation and N fixation of cowpea was investigated. Sandy and clayey soils were amended with TSC at rates of 0, 7.5, 15, 30, and 60 t ha-1. The shoot dry weight of cowpea plants 45 days after emergence (DAE) was greater in the TSC-amended than in the unamended soil. In the sandy soil, nodule dry weight increased with TSC application 45 DAE. In the clayey soil, 45 DAE, nodule dry weight decreased with TSC amendment levels greater than 7.5 t ha-1 compared to the unamended control. The application of TSC increased N accumulation in the cowpea plants. The results suggest that cowpea responds differently to TSC depending on the amendment rate and initial soil type.
Soil water retention and s index after crop rotation and chiseling
Authors: Calonego Juliano Carlos , Rosolem Ciro Antonio
Published: February 2012

Soil compaction can be minimized either mechanically or biologically, using plant species with vigorous root systems. An experiment was carried out with soybean (Glycine max) in rotation with triticale (X Triticosecale) and sunflower (Helianthus annuus) in fall-winter associated with pearl millet (Pennisetum glaucum), grain sorghum (Sorghum bicolor) or sunn hemp (Crotalaria juncea) in spring. Crop rotation under no-till was compared with mechanical chiseling. The experiment was carried out in Botucatu, São Paulo State, Brazil. Soil quality was estimated using the S index and soil water retention curves (in the layers of 0-0.05, 0.075-0.125, 0.15-0.20, 0.275-0.325, and 0.475-0.525 m deep). Crop rotation and chiseling improved soil quality, increasing the S index to over 0.035 to a depth of 20 cm in the soil profile. The improved soil quality, as shown by the S index, makes the use of mechanical chiseling unnecessary, since after 3 years the soil physical quality under no-tilled crop rotation and chiseling was similar.
Estimativa da capacidade de campo pela curva de retenção e pela densidade de fluxo da água
Authors: Brito Alexsandro dos Santos , Libardi Paulo Leonel , Mota Jaedson Cláudio Anunciato , Moraes Sergio Oliveira
Published: February 2012

A capacidade de campo é um parâmetro de inegável relevância para o manejo adequado da irrigação. A partir da determinação confiável do conteúdo de água no solo na capacidade de campo, pode-se otimizar a produtividade das culturas agrícolas, maximizando a eficiência do uso da água pelas plantas e evitando a contaminação do lençol freático por lixiviação de fertilizantes e agroquímicos. Nesse sentido, o trabalho teve como objetivo avaliar a capacidade de campo (a) pelo cálculo da densidade de fluxo da água durante o processo de redistribuição no experimento clássico de determinação desse parâmetro e (b) a partir de uma dada tensão da água na curva de retenção, em um Latossolo Vermelho-Amarelo textura média, localizado em área experimental da Escola Superior de Agricultura Luiz de Queiroz, município de Piracicaba, Estado de São Paulo (Brasil). Para isso, instalaram-se no solo, até a profundidade de 1,9 m, 60 tubos de acesso a uma sonda de nêutrons, numa rede de malha quadrada de 5 m (6 x 10 pontos amostrais), e, adjacente a cada tubo, dois tensiômetros, um a 0,75 m e outro a 0,85 m de profundidade. Nos 60 pontos (locais) amostrais, desenvolveu-se um experimento similar ao experimento clássico de determinação da capacidade de campo, no qual o solo foi devidamente submetido a uma lâmina de infiltração visando à saturação do seu perfil; sua superfície, coberta com lona plástica para evitar fluxo de água através dela; e a redistribuição da água, monitorada até a profundidade de 0,8 m durante 20 dias. Observou-se que o conteúdo de água correspondente a uma densidade de fluxo de 1,0 mm dia-1 é a melhor estimativa da capacidade de campo para esse solo, uma vez que as densidades de fluxo de 0,1 e 0,01 mm dia-1, também recomendadas para estimar a capacidade de campo, são muito baixas, a ponto de não terem sido alcançadas neste estudo. Quanto aos resultados obtidos pelo método baseado na curva de retenção, utilizando-se o conteúdo de água correspondente à tensão de 10 kPa em curvas de retenção elaboradas no campo e no laboratório também para os 60 pontos, na profundidade de 0,8 m, observou-se que os valores obtidos a partir das curvas de retenção elaboradas no campo e no laboratório subestimaram e superestimaram, respectivamente, aqueles baseados na densidade de fluxo da água de 1,0 mm dia-1, e a medida de campo foi mais confiável.
Distribution and vertical stratification of carbon and nitrogen in soil under different managements in the pampean region of Argentina
Authors: Álvarez Carina Rosa , Costantini Alejandro Oscar , Bono Alfredo , Taboada Miguel Ángel , Boem Flavio Hernán Gutiérrez , Fernández Patricia Lilia , Prystupa Pablo
Published: February 2012

One of the expected benefits of no-tillage systems is a higher rate of soil C sequestration. However, higher C retention in soil is not always apparent when no-tillage is applied, due e.g., to substantial differences in soil type and initial C content. The main purpose of this study was to evaluate the potential of no-tillage management to increase the stock of total organic C in soils of the Pampas region in Argentina. Forty crop fields under no-tillage and conventional tillage systems and seven undisturbed soils were sampled. Total organic C, total N, their fractions and stratification ratios and the C storage capacity of the soils under different managements were assessed in samples to a depth of 30 cm, in three layers (0-5, 5-15 and 15-30 cm). The differences between the C pools of the undisturbed and cultivated soils were significant (p < 0.05) and most pronounced in the top (0-5 cm) soil layer, with more active C near the soil surface (undisturbed > no-tillage > conventional tillage). Based on the stratification ratio of the labile C pool (0-5/5-15 cm), the untilled were separated from conventionally tilled areas. Much of the variation in potentially mineralizable C was explained by this active C fraction (R² = 0.61) and by total organic C (R² = 0.67). No-till soils did not accumulate more organic C than conventionally tilled soils in the 0-30 cm layer, but there was substantial stratification of total and active C pools at no till sites. If the C stratification ratio is really an indicator of soil quality, then the C storage potential of no-tillage would be greater than in conventional tillage, at least in the surface layers. Particulate organic C and potentially mineralizable C may be useful to evaluate variations in topsoil organic matter.
DRIS formulas for evaluation of nutritional status of cupuaçu trees
Authors: Dias Jairo Rafael Machado , Wadt Paulo Guilherme Salvador , Perez Daniel Vidal , Silva Lucielio Manoel da , Lemos Cleigiane de Oliveira
Published: February 2012

DRIS, an Diagnosis and Recommendation Integrated System, is a tool to evaluate the nutritional status of plants. Different DRIS formulas have been proposed to improve the efficiency of the crop nutrition diagnoses. The objective of this study was to compare the nutritional diagnosis of the formulas of Beaufils (1973), of Jones (1981) and of Elwali and Gascho (1984), based on the degree of agreement in commercial orchards of Theobrama grandiflorum trees. Leaf samples of 5 to 18 year-old cupuaçu trees were collected from 153 commercial orchards in agroforestry and monoculture systems in the state of Rondonia, Brazil. Bivariate relationships between nutrition concentrations in healthy trees were used to calculate DRIS norms. DRIS indices were calculated based on the different formulas and interpreted by the Potential Fertilizer Response method, in five categories. The DRIS norms, DRIS index calculations and their interpretations were developed using the DRIS Cupuaçu computer program (www.dris.com.br). The different DRIS formulas resulted in similar diagnoses with a degree of agreement of > 90% for the nutrients N, P, K, Ca, and Mg.
Effects of erosion and deposition on particle size distribution of deposited farmland soils on the chinese loess plateau
Authors: Zhao Pei , Shao Ming An , Omran Wail , Amer Abdel-monem Mohamed
Published: February 2012

Particle size distribution (PSD) in the soil profile is strongly related to erosion, deposition, and physical and chemical processes. Water cycling and plant growth are also affected by PSD. Material sedimented upstream of the dam constructions formed large areas of deposited farmland (DF) soils on the Chinese Loess Plateau (CLP), which has been the site of the most severe soil erosion in the world. Two DFs without tillage on the CLP were chosen to study the combined effect of erosion and check dams on PSD. Eighty-eight layers (each 10 cm thick) of filled deposited farmland (FDF) soils and 22 layers of silting deposited farmland (SDF) soils of each studied soil profile were collected and 932 soil samples were investigated using laser granulometry. The particle sizes were stratified in both DFs based on soil properties and erosion resistance. The obtained results of clay and silt fractions showed similar horizontal distribution, indicating parallel characteristics of erosion and deposition processes. Fine sand represented the largest fraction, suggesting the preferential detachment of this fraction. The most erodible range of particle sizes was 0.25-0.5 mm, followed by 0.2-0.25 mm in the studied soil profiles. The correlation between particle size and soil water contents tended to increase with increasing water contents in FDF. Due to the abundant shallow groundwater, the relationship between particle size and soil water content in SDF was lost. Further studies on PSD in the DF area are needed to enhance the conservation management of soil and water resources in this region.
Influence of organic-mineral fertilization of an oxisol on soil chemical properties and Bracharia brizantha production
Authors: Schiavoni Edmar Andrade , Alves Marlene Cristina , Souza Zigomar Menezes de , Costa Frederick Gonçalves
Published: February 2012

The use of organic-mineral fertilizer produced by the manufacturing industry of lysine and threonine amino acids can improve the fertility of tropical soils. The objective of this study was to evaluate the influence of different doses of the organic-mineral fertilizer named Ajifer L-14 on chemical properties and on the response with increased production of a forage on a Red Latosol in the northwestern region of São Paulo State, Brazil. A randomized block design was used with seven treatments and four replications. The treatments consisted of: T1- control (without application of Ajifer L-14); T2- control (natural vegetation); T3- mineral fertilization according to crop requirements and soil analysis (application of 1.35 kg plot-1 of urea, 2.20 single superphosphate, and 0.51 KCl, corresponding to 60 of N, 40 P2O5 and 30 kg ha-1 of K2O); T4- fertilization with Ajifer L-14 according to the recommendation resulting from the soil chemical analysis (40 L plot-1, corresponding to 60 kg ha-1 N); T5- fertilization with Ajifer L-14, at a rate of 150 % of the recommended values (60 L plot-1, corresponding to 90 kg ha-1 N); T6- fertilization with Ajifer L-14 at a rate of 50 % of the recommended values (20 L plot-1, corresponding to 30 kg ha-1 N); T7- fertilization with Ajifer L-14 at a rate of 125 % of the recommended values (50 L plot-1, corresponding to 75 kg ha-1 N); T8- fertilization with Ajifer L-14 at a rate of 75 % of the recommended values (30 L plot-1, corresponding to 45 kg ha-1 N). The following soil chemical properties were evaluated (layers 0.0-0.1 and 0.1-0.2 m): P, organic matter, pH, K+, Ca2+, Mg2+, cation exchange capacity, potential acidity, and base saturation. The application of this organic-mineral fertilizer does not influence the soil chemical properties. Regression analysis indicated a polynomial relationship between the application rates of organic-mineral fertilizer and the production of dry matter and crude protein of Bracharia Brizantha.