bluuebunny/crossref_metadata_2025 huggingface dataset:
Multi Objective Optimization of Friction Stir Processing Parameters on Mg AZ31B Alloy Using Grey Relational Analysis
Authors: Venkateswarlu Ganta , Davidson M. Joseph , Tagore Gogineni Ravindranath , Sammaiah Pulla
Published: March 2014

This paper presents the multi-response optimisation of friction stir processing (FSP) process of AZ 31 Mg alloy for an optimal parametric combination to yield maximum tensile strength and elongation using Taguchi and Grey relational analysis (GRA). In this study, the FSP process parameters such as rotational speed, traverse speed and tool tilt angle have been selected. The experiments were planned using Taguchi parametric design L
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with various combinations of process parameters. Statistical technique ANOVA was used to determine percentage of contribution of process parameters. Optimal results have been verified through confirmation experiments. The results indicate that rotational speed has more effect on responses followed by traverse speed and tool tilt angle. In addition, mathematical models were developed to establish relationship between different process variables and outcomes.
New CNC Programming Functions Based on Elliptical Motion
Authors: Omirou Sotiris L. , Fyrillas Marios M.
Published: March 2014

This paper proposes a set of four elliptical features that can enhance the programming capabilities of a modern CNC system. Namely, a real-time interpolation algorithm for motion generation along an ellipse and its offset, machining of an elliptical pocket, and drilling a series of equidistant holes along an elliptical path. The paper analytically describes the implementation of the new functions while the G-codes, along with their complementary requisite data needed to be introduced in the CNC part program, are exemplified with simulation and actual machining tests for each feature.
Pragmatic Approach for Assembly Lines Selection Based on Discrete-Event Simulation
Authors: Peças Paulo , Folgado Raquel , Henriques Elsa
Published: March 2014

This paper presents a pragmatic approach to the study of the influence of tasks time variability in the performance of linear and parallel assembly lines. Discrete event simulation is used to assess the performance of several configurations for two assembly line balancing problems, and for four different levels of time variability. From the simulation studies, a set of equations were developed allowing the prediction of the assembly line performance, measured by the cycle time for common ALBPs, with considerable accuracy. These equations show the interactions between the sum of average task times, the balancing difficulty of the problem and the tasks time variability, as well as the number of workstations and their level of parallelism. With these equations it's possible to reduce the search for the best candidate solutions (number of workstations and level of parallelism) for a given target cycle time, considering the time variability level of the problem. With this approach, the assembly line designer is able to select beforehand the possible feasible solutions in a more practical way when using simulation software.
Neural Correlates of Personal Space Intrusion
Authors: Holt Daphne J. , Cassidy Brittany S. , Yue Xiaomin , Rauch Scott L. , Boeke Emily A. , Nasr Shahin , Tootell Roger B. H. , Coombs Garth
Published: March 2014

A parietal-frontal network in primates is thought to support many behaviors occurring in the space around the body, including interpersonal interactions and maintenance of a particular “comfort zone” or distance from other people (“personal space”). To better understand this network in humans, we used functional MRI to measure the responses to moving objects (faces, cars, simple spheres) and the functional connectivity of two regions in this network, the dorsal intraparietal sulcus (DIPS) and the ventral premotor cortex (PMv). We found that both areas responded more strongly to faces that were moving toward (vs away from) subjects, but did not show this bias in response to comparable motion in control stimuli (cars or spheres). Moreover, these two regions were functionally interconnected. Tests of activity-behavior associations revealed that the strength of DIPS-PMv connectivity was correlated with the preferred distance that subjects chose to stand from an unfamiliar person (personal space size). In addition, the magnitude of DIPS and PMv responses was correlated with the preferred level of social activity. Together, these findings suggest that this parietal-frontal network plays a role in everyday interactions with others.
Antipsychotic-Like Actions of the Satiety Peptide, Amylin, in Ventral Striatal Regions Marked by Overlapping Calcitonin Receptor and RAMP-1 Gene Expression
Authors: Baisley Sarah K. , Bremer Quentin Z. , Bakshi Vaishali P. , Baldo Brian A.
Published: March 2014

Amylin is a calcitonin-related peptide co-secreted with insulin, which produces satiety through brainstem-localized receptors; however, its effects in forebrain are poorly understood. The nucleus accumbens shell (AcbSh) exhibits among the densest concentrations of high-affinity amylin binding; nevertheless, these receptors have not been explored beyond one study showing dopamine antagonist-like effects of intra-Acb amylin on feeding and associated behavior (Baldo and Kelley, 2001). Here, we investigated whether intra-Acb amylin signaling modulates prepulse inhibition (PPI), a measure of sensorimotor gating deficient in several illnesses including schizophrenia. First,in situhybridization revealed marked anatomical gradients for both receptor activity-modifying protein-1 (RAMP-1) and calcitonin receptor gene (CT-R) expression in striatum [coexpression of these genes yields a high-affinity amylin-1 receptor (AMY1-R)], with highest overlap in the medial AcbSh. Intra-AcbSh amylin infusions in rats (0, 30, and 100 ng) reversed amphetamine (AMPH)-induced PPI disruption without affecting baseline startle; dorsal striatal amylin infusions had no effect. Coinfusion of AC187 (20 μg), an antagonist for AMY1-R, blocked the ability of amylin to normalize AMPH-induced PPI disruption, showing the specificity of AcbSh amylin effects to the AMY1-R. Intra-AcbSh AC187 on its own disrupted PPI in a haloperidol-reversible manner (0.1 mg/kg). Thus, AMY1-R may be a potential target for the development of putative antipsychotics or adjunct treatments that oppose metabolic side effects of current medications. Moreover, AMY1-Rs may represent a novel way to modulate activity preferentially in ventral versus dorsal striatum.
Nicotine Enhances Excitability of Medial Habenular Neurons via Facilitation of Neurokinin Signaling
Authors: Dao Dang Q. , Perez Erika E. , Teng Yanfen , Dani John A. , De Biasi Mariella
Published: March 2014

The medial habenula (MHb) densely expresses nicotinic acetylcholine receptors (nAChRs) and participates in nicotine-related behaviors such as nicotine withdrawal and regulating nicotine intake. Although specific nAChR subunits are identified as being involved in withdrawal behavior, the cellular mechanisms through which nicotine acts to cause this aversive experience is unclear. Here, we demonstrate an interaction between the nicotinic and neurokinin signaling systems that may form the basis for some symptoms experienced during nicotine withdrawal. Using patch-clamp electrophysiology in mouse brain slices, we show that nicotine (1 μm) increases intrinsic excitability in MHb neurons. This nicotine-induced phenomenon requires α5-containing nAChRs and depends on intact neurokinin signaling. The effect is blocked by preincubation with neurokinin 1 (NK1; L-732138, 10 μm) and NK3 (SB222200, 2 μm) antagonists and mimicked by NK1 (substance P, 100 nm) and NK3 (neurokinin B [NKB], 100 nm) agonists. Microinjections (1 μl) of L-732138 (50 nm) and SB222200 (100 nm) into the MHb induces withdrawal behavior in chronic nicotine-treated (8.4 mg/kg/d, 2 weeks) mice. Conversely, withdrawal behavior is absent with analogous microinjections into the lateral habenula of nicotine-treated mice or in mice chronically treated with a vehicle solution. Further, chronic nicotine reduces nicotine's acute modulation of intrinsic excitability while sparing modulation by NKB. Our work elucidates the interplay between two neuromodulatory signaling systems in the brain through which nicotine acts to influence intrinsic excitability. More importantly, we document a neuroadaptation of this mechanism to chronic nicotine exposure and implicate these mechanisms collectively in the emergence of nicotine withdrawal behavior.
Memory Reactivation in Healthy Aging: Evidence of Stimulus-Specific Dedifferentiation
Authors: St-Laurent Marie , Abdi Hervé , Bondad Ashley , Buchsbaum Bradley R.
Published: March 2014

We investigated how aging affects the neural specificity of mental replay, the act of conjuring up past experiences in one's mind. We used functional magnetic resonance imaging (fMRI) and multivariate pattern analysis to quantify the similarity between brain activity elicited by the perception and memory of complex multimodal stimuli. Young and older human adults viewed and mentally replayed short videos from long-term memory while undergoing fMRI. We identified a wide array of cortical regions involved in visual, auditory, and spatial processing that supported stimulus-specific representation at perception as well as during mental replay. Evidence of age-related dedifferentiation was subtle at perception but more salient during mental replay, and age differences at perception could not account for older adults' reduced neural reactivation specificity. Performance on a post-scan recognition task for video details correlated with neural reactivation in young but not in older adults, indicating that in-scan reactivation benefited post-scan recognition in young adults, but that some older adults may have benefited from alternative rehearsal strategies. Although young adults recalled more details about the video stimuli than older adults on a post-scan recall task, patterns of neural reactivation correlated with post-scan recall in both age groups. These results demonstrate that the mechanisms supporting recall and recollection are linked to accurate neural reactivation in both young and older adults, but that age affects how efficiently these mechanisms can support memory's representational specificity in a way that cannot simply be accounted for by degraded sensory processes.
Passive Immunization with Tau Oligomer Monoclonal Antibody Reverses Tauopathy Phenotypes without Affecting Hyperphosphorylated Neurofibrillary Tangles
Authors: Castillo-Carranza Diana L. , Sengupta Urmi , Guerrero-Muñoz Marcos J. , Lasagna-Reeves Cristian A. , Gerson Julia E. , Singh Gurpreet , Estes D. Mark , Barrett Alan D. T. , Dineley Kelly T. , Jackson George R. , Kayed Rakez
Published: March 2014

Recent findings suggest that tau oligomers, which form before neurofibrillary tangles (NFTs), are the true neurotoxic tau entities in neurodegenerative tauopathies, including Alzheimer's disease (AD). Studies in animal models of tauopathy suggest that tau oligomers play a key role in eliciting behavioral and cognitive impairments. Here, we used a novel tau oligomer-specific monoclonal antibody (TOMA) for passive immunization in mice expressing mutant human tau. A single dose of TOMA administered either intravenously or intracerebroventricularly was sufficient to reverse both locomotor and memory deficits in a mouse model of tauopathy for 60 d, coincident with rapid reduction of tau oligomers but not phosphorylated NFTs or monomeric tau. Our data demonstrate that antibody protection is mediated by extracellular and rapid peripheral clearance. These findings provide the first direct evidence in support of a critical role for tau oligomers in disease progression and validate tau oligomers as a target for the treatment of AD and other neurodegenerative tauopathies.
Genetic Evidence for the Adhesion Protein IgSF9/Dasm1 to Regulate Inhibitory Synapse Development Independent of its Intracellular Domain
Authors: Mishra Archana , Traut Matthias H. , Becker Lore , Klopstock Thomas , Stein Valentin , Klein Rüdiger
Published: March 2014

Normal brain function requires balanced development of excitatory and inhibitory synapses. An imbalance in synaptic transmission underlies many brain disorders such as epilepsy, schizophrenia, and autism. Compared with excitatory synapses, relatively little is known about the molecular control of inhibitory synapse development. We used a genetic approach in mice to identify the Ig superfamily member IgSF9/Dasm1 as a candidate homophilic synaptic adhesion protein that regulates inhibitory synapse development. IgSF9 is expressed in pyramidal cells and subsets of interneurons in the CA1 region of hippocampus. Electrophysiological recordings of acute hippocampal slices revealed that genetic inactivation of theIgSF9gene resulted in fewer functional inhibitory synapses; however, the strength of the remaining synapses was unaltered. These physiological abnormalities were correlated with decreased expression of inhibitory synapse markers inIgSF9−/−mice, providing anatomical evidence for a reduction in inhibitory synapse numbers, whereas excitatory synapse development was normal. Surprisingly, knock-in mice expressing a mutant isoform of IgSF9 lacking the entire cytoplasmic domain (IgSF9ΔC/ΔCmice) had no defects in inhibitory synapse development, providing genetic evidence that IgSF9 regulates synapse development via ectodomain interactions rather than acting itself as a signaling receptor. Further, we found that IgSF9 mediated homotypic binding and cell aggregation, but failed to induce synapse formation, suggesting that IgSF9 acts as a cell adhesion molecule (CAM) to maintain synapses. JuvenileIgSF9−/−mice exhibited increased seizure susceptibility indicative of an imbalance in synaptic excitation and inhibition. These results provide genetic evidence for a specific role of IgSF9 in inhibitory synapse development/maintenance, presumably by its CAM-like activity.
Selective Microtubule-Based Transport of Dendritic Membrane Proteins Arises in Concert with Axon Specification
Authors: Petersen Jennifer D. , Kaech Stefanie , Banker Gary
Published: March 2014

The polarized distribution of membrane proteins to axonal or somatodendritic neuronal compartments is fundamental to nearly every aspect of neuronal function. The polarity of dendritic proteins depends on selective microtubule-based transport; the vesicles that carry these proteins are transported into dendrites but do not enter the axon. We used live-cell imaging of fluorescently tagged dendritic and axonal proteins combined with immunostaining for initial segment and cytoskeletal markers to evaluate different models of dendrite-selective transport in cultured rat hippocampal neurons. In mature neurons, dendritic vesicles that entered the base of the axon stopped at the proximal edge of the axon initial segment, defined by immunostaining for ankyrinG, rather than moving into the initial segment itself. In contrast, axonal vesicles passed through the initial segment without impediment. During development, dendrite-selective transport was detected shortly after axons formed, several days before initial segment assembly, before the appearance of a dense actin meshwork in the initial segment, and before dendrites acquire microtubules of mixed polarity orientation. Indeed, some elements of selective transport were detected even before axon specification. These findings are inconsistent with models for selective transport that depend on the presence of an F-actin-based cytoplasmic filter in the initial segment or that posit that transport into dendrites is mediated by dyneins translocating along minus-end out microtubules. Instead our results suggest that selective transport involves the coordinated regulation of the different motor proteins that mediate dendritic vesicle transport and that the selectivity of motor-microtubule interactions is one facet of this process.
Parametric Alpha- and Beta-Band Signatures of Supramodal Numerosity Information in Human Working Memory
Authors: Spitzer Bernhard , Fleck Sebastian , Blankenburg Felix
Published: March 2014

Numerosity can be assessed by analog estimation, similar to a continuous magnitude, or by discrete quantification of the individual items in a set. While the extent to which these two processes rely on common neural mechanisms remains debated, recent studies of sensory working memory (WM) have identified an oscillatory signature of continuous magnitude information, in terms of quantitative modulations of prefrontal upper beta activity (20–30 Hz). Here, we examined how such parametric oscillatory WM activity may also reflect the abstract assessment of the numerosity of discrete items. We recorded EEG while participants (n= 24) processed the number of stimulus pulses presented in the visual, auditory, or tactile modality, under otherwise identical experimental conditions. Behavioral response profiles showed varying degrees of analog estimation and of discretized quantification in the different modalities. During sustained processing in WM, the amplitude of posterior alpha oscillations (8–13 Hz) reflected the increased memory load associated with maintaining larger sets of discrete items. In contrast, earlier numerosity-dependent modulations of right prefrontal upper beta (20–30 Hz) specifically reflected the extent to which numerosity was assessed by analog estimation, both between and within presentation modalities. Together, the analog approximation—but not the discretized representation—of numerosity information exhibited a parametric oscillatory signature akin to a continuous sensory magnitude. The results suggest dissociable oscillatory mechanisms of abstract numerosity integration, at a supramodal processing stage in human WM.
Retrograde BMP Signaling Modulates Rapid Activity-Dependent Synaptic Growth via Presynaptic LIM Kinase Regulation of Cofilin
Authors: Piccioli Zachary D. , Littleton J. Troy
Published: March 2014

TheDrosophilaneuromuscular junction (NMJ) is capable of rapidly budding new presynaptic varicosities over the course of minutes in response to elevated neuronal activity. Using live imaging of synaptic growth, we characterized this dynamic process and demonstrated that rapid bouton budding requires retrograde bone morphogenic protein (BMP) signaling and local alteration in the presynaptic actin cytoskeleton. BMP acts during development to provide competence for rapid synaptic growth by regulating the levels of the Rho-type guanine nucleotide exchange factor Trio, a transcriptional output of BMP–Smad signaling. In a parallel pathway, we find that the BMP type II receptor Wit signals through the effector protein LIM domain kinase 1 (Limk) to regulate bouton budding. Limk interfaces with structural plasticity by controlling the activity of the actin depolymerizing protein Cofilin. Expression of constitutively active or inactive Cofilin in motor neurons demonstrates that increased Cofilin activity promotes rapid bouton formation in response to elevated synaptic activity. Correspondingly, the overexpression of Limk, which inhibits Cofilin, inhibits bouton budding. Live imaging of the presynaptic F-actin cytoskeleton reveals that activity-dependent bouton addition is accompanied by the formation of new F-actin puncta at sites of synaptic growth. Pharmacological disruption of actin turnover inhibits bouton budding, indicating that local changes in the actin cytoskeleton at pre-existing boutons precede new budding events. We propose that developmental BMP signaling potentiates NMJs for rapid activity-dependent structural plasticity that is achieved by muscle release of retrograde signals that regulate local presynaptic actin cytoskeletal dynamics.
Extended Wakefulness: Compromised Metabolics in and Degeneration of Locus Ceruleus Neurons
Authors: Zhang Jing , Zhu Yan , Zhan Guanxia , Fenik Polina , Panossian Lori , Wang Maxime M. , Reid Shayla , Lai David , Davis James G. , Baur Joseph A. , Veasey Sigrid
Published: March 2014

Modern society enables a shortening of sleep times, yet long-term consequences of extended wakefulness on the brain are largely unknown. Essential for optimal alertness, locus ceruleus neurons (LCns) are metabolically active neurons that fire at increased rates across sustained wakefulness. We hypothesized that wakefulness is a metabolic stressor to LCns and that, with extended wakefulness, adaptive mitochondrial metabolic responses fail and injury ensues. The nicotinamide adenine dinucleotide-dependent deacetylase sirtuin type 3 (SirT3) coordinates mitochondrial energy production and redox homeostasis. We find that brief wakefulness upregulates SirT3 and antioxidants in LCns, protecting metabolic homeostasis. Strikingly, mice lacking SirT3 lose the adaptive antioxidant response and incur oxidative injury in LCns across brief wakefulness. When wakefulness is extended for longer durations in wild-type mice, SirT3 protein declines in LCns, while oxidative stress and acetylation of mitochondrial proteins, including electron transport chain complex I proteins, increase. In parallel with metabolic dyshomeostasis, apoptosis is activated and LCns are lost. This work identifies mitochondrial stress in LCns upon wakefulness, highlights an essential role for SirT3 activation in maintaining metabolic homeostasis in LCns across wakefulness, and demonstrates that extended wakefulness results in reduced SirT3 activity and, ultimately, degeneration of LCns.
Causal Control of Medial–Frontal Cortex Governs Electrophysiological and Behavioral Indices of Performance Monitoring and Learning
Authors: Reinhart Robert M. G. , Woodman Geoffrey F.
Published: March 2014

Adaptive human behavior depends on the capacity to adjust cognitive processing after an error. Here we show that transcranial direct current stimulation of medial–frontal cortex provides causal control over the electrophysiological responses of the human brain to errors and feedback. Using one direction of current flow, we eliminated performance-monitoring activity, reduced behavioral adjustments after an error, and slowed learning. By reversing the current flow in the same subjects, we enhanced performance-monitoring activity, increased behavioral adjustments after an error, and sped learning. These beneficial effects fundamentally improved cognition for nearly 5 h after 20 min of noninvasive stimulation. The stimulation selectively influenced the potentials indexing error and feedback processing without changing potentials indexing mechanisms of perceptual or response processing. Our findings demonstrate that the functioning of mechanisms of cognitive control and learning can be up- or down-regulated using noninvasive stimulation of medial–frontal cortex in the human brain.
A new generalization of the logarithmic series distribution
Authors: Mishra A.
Published: March 2014

A new generalization of the logarithmic series distribution has been obtained as a limiting case of the zero-truncated Mishra’s [10] generalized negative binomial distribution (GNBD). This distribution has an advantage over the Mishra’s [9] quasi logarithmic series distribution (QLSD) as its moments appear in compact forms unlike the QLSD. This makes the estimation of parameters easier by the method of moments. The first four moments of this distribution have been obtained and the distribution has been fitted to some well known data-sets to test its goodness of fit.
The influence of weakly \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage{bbm} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \(\mathcal{H}\) \end{document}-subgroups on the structure of finite groups
Authors: Asaad M. , Al-Shomrani M. , Heliel A.
Published: March 2014

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\end{document}-subgroup in G, where m is a fixed positive integer. Our results improve and extend the main results of Skiba [13], Jaraden and Skiba [11], Guo and Wei [8], Tong-Veit [15] and Li et al. [12].
Convergence of logarithmic means of multiple Walsh-Fourier series
Authors: Gát György , Goginava Ushangi
Published: March 2014

The maximal Orlicz spaces such that the mixed logarithmic means of multiple Walsh-Fourier series for the functions from these spaces converge in measure and in norm are found.
Integrative Chemistry-Based Generation of Novel Three Dimensional Macrocellular Carbonaceous Biofuel Cell
Authors: Flexer Victoria , Brun Nicolas , Destribats Mathieu , Backov Rénal , Mano Nicolas
Published: March 2014

Here we report the first membrane-less biofuel cell made by using three-dimensional carbonaceous foam electrodes. We first developed a new synthetic pathway to produce a new carbonaceous foam electrode material with increased porosity both in the meso and macroporous scale. We proved that by increasing the porosity of our three-dimensional foams we could increase the current density of our modified electrodes. Then, by choosing the right combination of enzyme and mediator, and the right loading of active components, we achieved unprecedentedly high current densities for an anodic system. Finally, we combined the improved cathode and anode to build a new membrane-less hybrid enzymatic biofuel cell consisting of a mediated anode and a mediator-less cathode.
Mitral flow propagation velocity in non-sedated healthy cats
Authors: Silva A.C. , Muzzi R.A.L. , Oberlender G. , Muzzi L.A.L. , Coelho M.R. , Nogueira R.B.
Published: March 2014

Mitral flow propagation velocity (Vp) is an index used to evaluate the left ventricular diastolic function. Its influence on human and small animal cardiopathies has been studied; however there are few reports evaluating this variable in domestic felines. In addition, there is a lack of studies in non-sedated healthy cats. Therefore, the purpose of this study was to establish values for Vp and its correlation with other echocardiographic indexes in non-sedated healthy cats in order to provide new perspectives related to diastolic function in this species. Twenty-six clinically healthy cats were submitted to echocardiography to assess the animals' cardiac conditions. Variables such as age, heart rate (HR), body surface area (BSA), initial (E mitral) and late (A mitral) ventricular filling waves, isovolumic relaxation time (IVRT) and E/IVRT relation were correlated to Vp. No proven relation between any of these variables and Vp was observed in this present study, except for HR and BSA. In the variability analysis, higher values were verified for inter-observer analysis. This study concludes that Vp proved to be an useful index for estimating left ventricular relaxation in non-sedated healthy domestic cats and provides reference ranges for this variable.
Ejaculados individuais e pools de sêmen: diferenças em condições experimentais
Authors: Mascarenhas R.M. , Xavier P.R. , Marques Júnior A.P.
Published: March 2014

Avaliaram-se ejaculados caninos individuais e pools de sêmen submetidos a dois tratamentos de renovação do meio diluidor. Sêmen de seis cães foi coletado, na forma de ejaculados individuais e pools de sêmen, diluído na proporção de 1:1 em meio Tris-Gema, centrifugado a 500g/10min, e o pellet ressuspendido até concentração final de 50x10(6) espermatozoides/mL. O sêmen foi resfriado a 0,26ºC/min, entre 37 e 16ºC, e 0,08ºC/min, entre 16 a 8ºC, e mantido em geladeira a 5ºC por 14 dias. No Tratamento 1, o meio diluidor foi renovado a cada seis dias, e no Tratamento 2 aos 12 dias. O sêmen foi avaliado, a cada 48 horas, quanto à motilidade espermática, utilizando-se o Sperm Class Analyser® (SCA), e quanto à integridade de membranas pelo teste hiposmótico e coloração com PI/CFDA. A formação de pools de sêmen simplificou sua manipulação, principalmente com relação ao aumento do volume da amostra disponível; no entanto, resultados obtidos a partir de ejaculados individuais mostraram diferenças entre tratamentos, não identificadas nos pools de sêmen.
Avaliação histopatológica de órgãos reprodutivos e bexiga de fêmeas suínas descartadas
Authors: Ritterbusch G.A. , Rocha C. Sá , Ciacci-Zanella J.R. , Amaral A.L. , Coldebella A. , Ascoli K.R. , Mores N.
Published: March 2014

Em um sistema intensivo de produção de suínos, as falhas reprodutivas são uma das principais razões de descarte de matrizes e queda nos índices produtivos. A infecção urinária (cistite) e as endometrites são consideradas importantes causas de descarte em fêmeas suínas, por terem consequências reprodutivas relevantes e elevarem a taxa de reposição do plantel. O presente estudo teve o objetivo de avaliar o aparelho reprodutivo e a bexiga de fêmeas suínas de descarte normal de granjas, bem como investigar a existência de relação entre as patologias encontradas. Foram examinadas 79 matrizes suínas oriundas de 20 rebanhos localizados no Estado de Santa Catarina. De cada fêmea foram coletados os ovários, fragmentos de útero e bexiga. Dentre as fêmeas avaliadas, 32 (40,5%) tinham diferentes graduações de cistite, 24 (30,4%) tinham algum tipo de inflamação uterina, e 9 (11,4%) estavam em anestro, com ovários inativos. Contudo, não foi observada dependência significativa entre cistite e endometrite nas amostras analisadas.
Ultrassonografia transcraniana em cães hígidos: padronização da técnica e descrição anatômica
Authors: Cintra T.C.F. , Carvalho C.F. , Canola J.C. , Nepomuceno A.C.
Published: March 2014

O interesse pelo estudo do sistema nervoso central vem crescendo na Medicina Veterinária. A ultrassonografia transcraniana (USTC) tem a vantagem de não ser invasiva e ter baixo custo quando comparada à tomografia computadorizada (TC) e à imagem em ressonância magnética (RM). O osso temporal tem sido utilizado como janela acústica na realização da USTC em seres humanos. Este trabalho teve como objetivo correlacionar imagens ultrassonográficas transcranianas obtidas através das janelas temporal e occipital com a anatomia encefálica em cães adultos hígidos, e padronizar a técnica de exame. Foram utilizados 37 cães adultos, sem raça definida: 30 animais in vivo, para realização da técnica, e sete cadáveres, para a secção do encéfalo, à similitude dos planos de imagem obtidos ao USTC. Os dados foram analisados utilizando o teste não paramétrico de Wilcoxon. Os resultados obtidos indicaram que a USTC é um método diagnóstico viável para a avaliação do encéfalo de cães com peso corporal até 10kg, por meio de planos dorsal e dorsais oblíquos, sem a necessidade de anestesiar o paciente.
Miocardite crônica em um cão naturalmente infectado com Leishmania (Leishmania) infantum chagasi: aspectos clínicos e patológicos
Authors: Mendes R.S. , Gurjão T.A. , Oliveira L.M. , Santana V.L. , Tafuri W.L. , Santos J.R.S. , Dantas A.F.M. , Souza A.P.
Published: March 2014

A leishmaniose visceral (LV) é uma doença infecciosa crônica frequentemente fatal causada pela Leishmania infantum chagasi nas Américas. A enfermidade pode acometer vários órgãos, determinando diferentes manifestações clínicas. Contudo o envolvimento do coração raramente tem sido reportado em cães infectados por Leishmania sp. Dessa forma, descreve-se um caso de miocardite crônica com repercussões clínicas e patológicas em um cão naturalmente infectado por Leishmania infantum chagasi. A positividade para Leishmaniose Visceral foi determinada pela presença de anticorpos antiLeishmania sp. nos testes sorológicos (RIFI, ELISA e DPP) e confirmada por visualização de formas amastigotas de Leishmania sp. em punção aspirativa do linfonodo poplíteo. O exame cardiovascular revelou alterações radiográficas, eletrocardiográficas, na pressão arterial e nos biomarcardores cardíacos. Após eutanásia, amostras de tecido cardíaco foram avaliadas histologicamente e submetidas à imunomarcação, onde foi observado infiltrado mononuclear (plasmo-histiolinfocitário), com presença de estruturas arredondadas de coloracão marrom-amareladas (imunomarcadas), indicando formas amastigotas de Leishmania infantum chagasi no miocárdio. Os aspectos etiopatogênicos da leishmaniose visceral sobre o miocárdio neste caso podem estar relacionados tanto à presença do parasita quanto à resposta "reacional inespecífica" do tecido à agressão do parasita no organismo. Todavia ainda não se sabem se as cepas de Leishmania infantum chagasi da região semiárida paraibana apresentam algum tropismo por tecido cardíaco ou se induzem a reação imunológica cruzada, com implicações clínicas.
Produção de biocompostos com atividade antimicrobiana de Streptomyces sp. ante isolados de mastite caprina
Authors: Nascimento T. Pajeú , Porto C.S. , Teixeira M.F.S. , Porto T.S. , Porto A.L.F.
Published: March 2014

Actinomicetos são um dos principais produtores de enzimas, vitaminas e metabólitos secundários, destacando-se o gênero Streptomyces, o qual tem uma ampla capacidade de produção de antibióticos eficazes no combate a diferentes microrganismos, entre eles o Staphylococcus sp. Em virtude dessa eficiência no combate a patógenos, o objetivo deste trabalho foi avaliar a produção de metabólitos com atividade antimicrobiana produzidos por 67 Streptomyces isolados de liquens da região amazônica, ante isolados de mastite caprina (Staphylococcus aureus) do estado de Pernambuco, Brasil. Foi utilizado um planejamento fatorial para avaliar a influência das fontes de carbono (glicose) 0%, 0,5% e 1% e de nitrogênio (farinha de soja) 1%, 2,5% e 4% na produção dos antimicrobianos, bem como das variáveis pH, biomassa e atividade antimicrobiana. Dos Streptomyces estudados, o DPUA 1566 foi o que se destacou por formação de halos de inibição entre 18 e 26mm ante os isolados de mastite caprina. Foi possível verificar que a fonte de carbono inibiu a produção de antimicrobianos quando submetidos a uma concentração de glicose de 1%; com a retirada desta, os Streptomyces apresentaram uma elevada capacidade de produção de metabólitos com atividade antimicrobiana tendo potencial para o tratamento de mastite caprina.
Dextrocardia with situs solitus and inversion apex-basis axis in lesser anteater (Tamandua tetradactyla): case report
Authors: Pinheiro V.L.C. , Pereira L.C. , Lima A.R. , Branco E.
Published: March 2014

Dextrocardia is a rare cardiac anomaly where the heart is situated on the right antimeres of the thorax. This study had the objective of describing a case of dextrocardia with situs solitus and apex-basis axis inversion in a lesser anteater (Tamandua tetradactyla) between five evaluated animals, all from the area of Mine Bauxite - Paragominas - Para. The arterial system was filled with contrasted latex and the animals were fixed with 10% formaldehyde and a posterior dissection was done. The heart of an animal was found in right antimere with inversion of the base-apex axis. The right atrium was more developed then the left and the pulmonary veins arrived directly in the left ventricle. The main vases of the base were identified with some topographic alterations resulting in: aorta dorsal to the cava caudal vein, pulmonary artery dorsal and cranial to aorta, pulmonary veins ventral to the pulmonary artery, cava caudal vein in ventral plain and cava cranial vein in dorsal plan in relation to the other vessels. Internally there were four cardiac chambers, with absence of septal communication.
Avaliação ultrassonográfica do bulbo ocular em cães submetidos à facoemulsificação com ou sem implante de lente intraocular
Authors: Pavan P.T. , Ranzani J.J.T. , Almeida M.F. , Mamprim M.J. , Brandão C.V.S.
Published: March 2014

Este trabalho objetivou descrever e comparar as alterações ultrassonográficas encontradas em bulbos oculares de cães submetidos à facoemulsificação, com ou sem implante de lente intraocular (LIO), no intuito de auxiliar no diagnóstico de alterações decorrentes da cirurgia e do implante da LIO, bem como sua correspondência com alterações clínicas. Dezenove cães portadores de catarata (21 olhos) foram submetidos ao procedimento de facoemulsificação e avaliados no pós-operatório tardio, aos cinco anos de evolução. Constituíram-se três grupos experimentais: afácicos (CA), formados por 11 cães; pseudofácicos (PP), com implante de duas LIOs em piggyback (n=5); e pseudofácicos (PL), com implante de uma LIO veterinária (n=5). Após exame oftálmico, todos foram submetidos ao exame ultrassonográfico, sob anestesia tópica, com transdutor linear multifrequencial de 10MHz; adicionalmente foram avaliadas medidas biométricas dos bulbos do olho. As principais alterações observadas foram: luxação da LIO, descolamento de retina, hialose asteroide e degeneração vítrea. O exame ultrassonográfico mostrou-se como excelente ferramenta diagnóstica e possibilitou a confirmação e a classificação dessas alterações. Na biometria ocular, pelas medidas entre o corpo ciliar e a câmara vítrea, o implante em piggyback resultou em redução destas em relação aos demais procedimentos instituídos, não havendo diferença ente o comprimento axial e a câmara anterior.
Perfil de sensibilidade de células sésseis e planctônicas de Escherichia coli a antimicrobianos usados no tratamento da mastite bovina
Authors: Costa J.C.M. , Espeschit I.F. , Pieri F.A. , Carvalho I.A. , Moreira M.A.S.
Published: March 2014

Escherichia coli é um micro-organismo altamente adaptativo e sua habilidade em formar biofilmes pode ser fundamental na resistência a tratamentos com antimicrobianos. A avaliação da concentração mínima inibitória (CMI) vem sendo utilizada para verificar a sensibilidade dos micro-organismos aos antimicrobianos. Entretanto, quando se avaliam células sésseis, a concentração do antimicrobiano requerido para erradicação do biofilme é maior do que a determinada pela CMI. Objetivou-se comparar as CMI com as concentrações mínimas de erradicação de biofilmes (CMEB) de antimicrobianos usados no tratamento da mastite em 27 isolados de E. coli produtores de biofilmes provenientes de mastite. Os isolados foram submetidos a testes de sensibilidade a antimicrobianos usados no tratamento da mastite, tanto para células planctônicas, por meio da CMI, quanto para células sésseis, pela avaliação da CMEB. Os resultados revelaram uma alta sensibilidade: apenas quatro (14,8%) isolados obtiveram valores da CMI elevados, variando de 4 a 10µg/mL, sendo classificados como resistentes. Para os demais isolados (85,2%), os valores foram menores, variando de 0,125 a 2µg/mL, classificados como sensíveis. A avaliação de CMEB indicou que a concentração dos antimicrobianos necessária para eliminar as células sésseis variou de 100µg/mL a 500µg/mL. Os valores de CMEB foram significativamente maiores nos isolados grandes e moderados produtores de biofilmes em relação aos isolados fracos produtores de biofilmes (p<0,001). Não houve correlação entre os valores de CMEB e CMI (p>0,05). A escolha da terapêutica antimicrobiana correta para o tratamento de infecções intramamárias em bovinos relacionadas com a produção de biofilmes parece exigir a aplicação de testes mais específicos. Testes de susceptibilidade antimicrobiana baseados apenas em valores de CMI mostraram-se ineficazes em determinar com precisão a susceptibilidade das células bacterianas sésseis.
Viabilidade de embriões vitrificados oriundos da fertilização in vitro de oócitos de vacas suplementadas com canola
Authors: Domingues M.C.N. , Rigolon L.P. , Cavalieri F.L.B. , Seko M.B. , Albuquerque K. , Zancheta C.G.
Published: March 2014

Avaliou-se a produção de oócitos e embriões de vacas Nelore in vitro e a resistência à vitrificação. Foram utilizadas 12 vacas Nelore, distribuídas aleatoriamente em dois tratamentos: T1-tratados com canola em grão (2,0kg/animal/dia) e T2-controle. Cada animal foi aspirado quatro vezes para obtenção de óocitos para fecundação in vitro. Os oócitos foram quantificados e classificados em viáveis ou inviáveis. Os zigotos foram cultivados in vitro e, sete dias após, os embriões foram avaliados quanto à qualidade e grau de desenvolvimento e vitrificados em hastes próprias. Na sequência, foram descongelados e cultivados em 6, 12 e 24 horas, observando-se a taxa de expansão e eclosão. Não houve diferenças (P>0,05) no número total de oócitos viáveis, T1=12,7% e T2=11,0%, na taxa de clivagem, T1=60,6% e T2=61,4%, e taxa de blastocistos, T1=23,7% e T2=27,0%, em função do tratamento. Também não houve influência na taxa de re-expansão, T1=70,5 e T2=59,6%, após a vitrificação e descongelamento. Todavia houve diferença (P<0,06) para a taxa de eclosão, T1=69,2 e T2=35,7. Conclui-se que a adição de canola na dieta de vacas não alterou a produção de embriões; entretanto, os embriões resultantes de oócitos coletados de vacas alimentadas com canola são mais resistentes à vitrificação.
Platelet rich plasma associated with heterologous fresh and thawed chondrocytes on osteochondral lesions of rabbits
Authors: Filgueiras R.R. , Del Carlo R.J. , Alves N.P. , Viloria M.I.V. , McManus C.M. , Castro M.B. , Filgueiras F.P.F. , Monteiro B.S. , Almeida R.M. , Andrade R.R.
Published: March 2014

Chondrocytes obtained from stifle joint of New Zealand White rabbits were cultivated. Half of cells were maintained in culture for later implantation and the others frozen during six months to evaluate viability. A circular osteochondral defect was created in the right stifle of other twenty seven rabbits. The control group (CG) received no treatment. The thawed (TH) and fresh (FH) heterologous groups received, respectively, an implant of cultivated thawed or fresh heterologous chondrocytes associated with platelet rich plasma (PRP). The CG group showed greatest pain and lameness compared to the other groups seven days after the implantation. Microscopically, at 45 and 90 days, the TH and FH groups showed filling with cartilaginous tissue containing chondrocytes surrounded by a dense matrix of glycosaminoglycans. In the CG group, healing occurred with vascularized fibrous connective tissue without integration to the subchondral bone. Cryopreserved heterologous chondrocytes were viable for implantation and healing of osteochondral lesions; the association with PRP allows the fixation of cells in the lesion and offers growth factors which accelerates repair with tissue similar to articular hyaline cartilage.
Avaliação macroscópica e microscópica de implante de Biomembrana em estômago de coelhos (Oryctolagus cuniculus)
Authors: Ferreira A.R.S. , Machado M.R.F. , Melo V.S. , Martins L.L. , Leal L.M. , Sartori L.C.A.
Published: March 2014

Neste estudo foi implantado um retalho de biomembrana de látex natural em substituição a um fragmento da parede de estômago de coelhos albinos, raça Nova Zelândia, adultos, machos não castrados (n=12), com o intuito de avaliar o processo de reparação tecidual no que se refere à biocompatibilidade, à capacidade de reparação tecidual e a possíveis complicações. Aos 15, 30 e 60 dias de pós-operatório, os animais foram sacrificados, mediante o emprego de tiopental sódico (200mg kg-1), para posterior avaliação macroscópica e análise histopatológica da interface do implante com o tecido nativo. Macroscopicamente, aos 15, 30 e 60 dias de pós-operatório observou-se presença de aderências na face serosa. Aos 60 dias de pós-operatório, em todos os animais avaliados, a biomembrana não foi encontrada. Sob microscopia de luz, aos 15 e 30 dias, verificaram-se descontinuidade das camadas muscular e mucosa, presença de infiltrado inflamatório polimorfonuclear. Foram visualizados vasos sanguíneos e fibras musculares. Aos 60 dias, as camadas mucosa, muscular estavam completamente reconstituídas. O implante foi biocompatível e forneceu arcabouço para orientação e desenvolvimento das camadas teciduais do estômago, mediante processos de reparação, restabelecendo a estrutura do órgão.
Stability and adaptability analysis of Tabapuã bulls for performance traits according to the herd level
Authors: Marçal M.F. , Ferraz Filho P.B. , Souza J.C. , Silva L.O.C. , Gomes F.J. , Freitas J.A.
Published: March 2014

In order to study the stability and adaptability of Tabapuã cattle for the characteristic weight at 120 days of maternal effect, we used methods based on linear regression. The analysis included differences in the expected progeny of five sire sin herds located in four farms in the states of Bahia, (herds 1and 2), Paraná (herd 3) and Minas Gerais (herd 4). The results show that the performance of bulls depend largely on the genetic variability of the matrices for different characteristics in herds studied, allowing the recommendation of a specific breeding herd. Analyses of adaptability and stability discriminated performance differences in herds. Bulls were identified as adapted and perfectly stable, bulls with general adaptation, and with specific adaptation to favorable and unfavorable environments.
Radioisótopo e modelagem matemática na avaliação da suplementação de fitase em dietas para suínos em crescimento
Authors: Mota L.C. , Moreira J.A. , Patino R.M. , Oliveira R.L.R , Vitti D.M.S.S.
Published: March 2014

O objetivo deste trabalho foi avaliar os efeitos da inclusão de níveis crescentes de enzima fitase em dietas para suínos em fase de crescimento, por meio do uso de modelagem matemática. Foram utilizados dados de 20 leitões mestiços, machos castrados, pesando em média, 26,8kg. Os animais ficaram alojados em gaiolas metabólicas individuais para a coleta de fezes e urina, onde permaneceram por um período de 17 dias. Utilizou-se o delineamento experimental de blocos ao acaso, com cinco tratamentos e quatro repetições. A dieta experimental fornecida aos leitões foi à base de milho e farelo de soja, suplementada com cinco níveis crescentes de enzima fitase (0, 250, 500, 750 e 1000UF/kg), correspondendo a 0; 0,01; 0,02; 0,03 e 0,04%, respectivamente. As variáveis avaliadas foram: ingestão, excreção, fluxo e refluxo do P nos compartimentos (trato digestivo, corrente sanguínea, tecidos moles e ossos). A enzima fitase não interferiu no P consumido (P>0,05 (F10), no P excretado na urina (F02), no fluxo e refluxo do P nos ossos (F32 e F23) e nos tecidos moles (F42 e F24), entretanto observou-se redução no P excretado nas fezes (F01) em 8,92%; 26,76%; 22,53% e 28,64% para os níveis 0, 250, 500, 750 e 1000UF/kg, respectivamente, e efeito linear positivo para o P endógeno (F12). Pode-se utilizar dietas à base de milho e farelo de soja com 50% de P por fosfato bicálcico, adicionando-se 250UF/kg de dieta para suínos em crescimento, o que reduz em 27% as excreções de P nas fezes.