The lack of clear understanding of the pathophysiology of chronic pain could explain why we currently have only a few effective treatments. Understanding how pain relief is realised during placebo ...analgesia could help develop improved treatments for chronic pain. Here, we tested whether experimental placebo analgesia was associated with altered resting-state cortical activity in the alpha frequency band of the electroencephalogram (EEG). Alpha oscillations have been shown to be influenced by top-down processes, which are thought to underpin the placebo response. Seventy-three healthy volunteers, split into placebo or control groups, took part in a well-established experimental placebo procedure involving treatment with a sham analgesic cream. We recorded ongoing (resting) EEG activity before, during, and after the sham treatment. We show that resting alpha activity is modified by placebo analgesia. Post-treatment, alpha activity increased significantly in the placebo group only (p < 0.001). Source analysis suggested that this alpha activity might have been generated in medial components of the pain network, including dorsal anterior cingulate cortex, medial prefrontal cortex, and left insula. These changes are consistent with a cognitive state of pain expectancy, a key driver of the placebo analgesic response. The manipulation of alpha activity may therefore present an exciting avenue for the development of treatments that directly alter endogenous processes to better control pain.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Exposure to the hight-fat diet may alter the control of food intake promoting hyperphagia and obesity. The objective of this study was to investigate the effects of this diet on dopamine receptors ...(drd1 and drd2), proopiomelanocortin (pomc), neuropeptideY (npy) genes expression, and preference food in adult rats. Wistar female rats were fed a hight-fat or control diet during pregnancy and lactation. The offspring were allocated into groups: Lactation - Control (C) and High-fat (H). Post-weaning - Control Control (CC), offspring of mothers C, fed a control diet after weaning; Control Hight-fat (CH), offspring of mothers C, fed a hight-fat diet after weaning; Hight-fat Control (HC), offspring of mothers H, fed with control diet after weaning; and Hight-fat Hight-fat (HH), offspring of mothers H, fed a H diet after weaning. The groups CH and HH presented greater expression of drd1 in comparison to the CC. The drd2 of CH and HC presented higher gene expression than did CC. HH presented higher pomc expression in comparison to the other groups. HC also presented greater expression in comparison to CH. The npy of HH presented greater expression in relation to CH and HC. HH and HC have had a higher preference for a high-fat diet at 102º life's day. The high-fat diet altered the gene expression of the drd1, drd2, pomc and npy, and influencing the food preference for high-fat diet.
We describe a Bayesian estimation and inference procedure for fMRI time series based on the use of General Linear Models (GLMs). Importantly, we use a spatial prior on regression coefficients which ...embodies our prior knowledge that evoked responses are spatially contiguous and locally homogeneous. Further, using a computationally efficient Variational Bayes framework, we are able to let the data determine the optimal amount of smoothing. We assume an arbitrary order Auto-Regressive (AR) model for the errors. Our model generalizes earlier work on voxel-wise estimation of GLM-AR models and inference in GLMs using Posterior Probability Maps (PPMs). Results are shown on simulated data and on data from an event-related fMRI experiment.
Non‐metallic inclusion removal from liquid steel in a tundish is studied using two‐phase flow modelling by Particle Image Velocimetry (PIV) techniques and mathematical simulation. The removal ...efficiency is studied as a function of Flow Control Devices (FCD) arrangements inside the tundish, gas bubbling and mass flow rate. The mathematical two‐phase model includes an Eulerian‐Eulerian approach for the gas‐liquid system and a Lagrange approach for the solid particles trajectories. The validation of this model was acceptably proved through PIV measurements and colour tracer experiments in a two‐phase water model. The removal efficiency of the tundish in the cases of gas bubbling becomes independent of particle size and FCD arrangements. An increase of mass flow rate decreases the particle mean residence time in the tundish and therefore the removal efficiency. Under the same conditions coupling‐uncoupling phenomena of solid particles from the liquid flow depends strongly on their response time. Where this phenomena occurs, it is determined that the particle response time in the model goes from 10−5 to 10−3 seconds for particle size ranging from 20 to 160 μm, respectively; this transition is dependent on particles size and mass flow rate.
ABSTRACT Brucella ovis, a non-zoonotic species, is the etiological agent of ovine brucellosis, an infectious disease of clinical or subclinical occurrence in sheep flocks. Until then, there is no ...serological study of anti-Brucella ovis antibodies in purebred sheep herds. This study aimed to determine the presence of anti-Brucella ovis antibodies in purebred sheep flocks with breeding purposes from Parana State. Blood samples from 728 animals, of which 563 were females and 165 males, between 8 and 56 months of age from the six major sheep producing mesoregions of Parana, were submitted to detection of anti-Brucella ovis antibodies by the Agar Gel Immunodiffusion technique using an antigen from the bacteria Brucella ovis (Reo 198). The results indicate the presence of this disease in purebred sheep from Parana State in a low occurrence of 0.27% (2/728). The only two positive animals were rams, Santa Inês breed, from the same flock in the East Center region of Parana, without clinical disease. In conclusion, Brucella ovis is present in purebred sheep in Parana State, Brazil, and this low occurrence may have occurred due to rigorous breeding systems that may contribute to reduce the transmission of this disease.
RESUMO Brucella ovis, espécie não zoonótica, é o agente etiológico da brucelose ovina, doença infecciosa de ocorrência clínica ou subclínica. Atualmente, não existe estudo sorológico de anticorpos anti-Brucella ovis em rebanhos de ovinos puros de origem. Este estudo teve como objetivo determinar a presença de anticorpos anti-Brucella ovis em rebanhos ovinos de raça pura de origem, com fins reprodutivos do estado do Paraná. Amostras de sangue de 728 animais, sendo 563 fêmeas e 165 machos, entre oito e 56 meses de idade, pertencentes a seis principais mesorregiões produtoras de ovinos no Paraná, foram submetidas à detecção de anticorpos anti-Brucella ovis pela técnica de imunodifusão em ágar gel usando-se um antígeno da bactéria Brucella ovis (Reo 198). Os resultados indicam a presença da doença em ovinos puros de origem do estado do Paraná em baixa ocorrência de 0,27% (2/728). Os dois únicos animais positivos foram reprodutores da raça Santa Inês, do mesmo rebanho da região Centro Leste do Paraná, sem manifestação clínica. Em conclusão, Brucella ovis está presente em ovinos puros de origem no estado do Paraná, e essa baixa ocorrência pode ter ocorrido devido a sistemas rigorosos de criação, que podem contribuir para a redução da transmissão dessa doença.
ABSTRACT The aim of this work was to report the occurrence of dicephalus iniodymus monauchenos in a Nellore newborn. A three-days old calf, from in vitro production, with duplication of the head and ...a history of cesarean birth was attended. On physical examination, the dicephalus, iniodymus and monauchenos, which were almost the same size and shape, had four eyes and four ears. Computed tomography showed the presence of two skulls fused with a common occipital foramen, two nasopharynxes, oropharynxes with the presence of a cleft lip and a cleft palate in the right head, which continued in a single esophagus and a single trachea. At necropsy, the presence of duplication of the cerebrum and cerebellum was observed, with union of the parts in the region of the trapezoid body of the brainstem and continued as a single spinal cord. This study characterizes the clinical, tomographic, and necropsy findings of a dicephalus Nelore neonate.
RESUMO O objetivo deste trabalho foi relatar a ocorrência de Dicephalus Iniodymus Monauchenos em um neonato da raça Nelore de produção in vitro. Foi atendida uma fêmea bovina, de três dias de idade, com duplicação das cabeças e histórico de nascimento por meio de cesariana. No exame físico, observou-se a dicefalia, Iniodymus e Monauchenos, apresentando quatro olhos e quatro orelhas. Na tomografia computadorizada, constatou-se a presença de dois crânios fundidos com um forame occipital comum, duas nasofaringes, orofaringes com presença de lábio leporino e fenda palatina na cabeça direita, que continuavam em um único esôfago e em uma única traqueia. Na necropsia, observou-se a presença de duplicação do encéfalo e cerebelo, com união das partes na região do corpo trapezoide do tronco encefálico, que continuavam como uma única medula espinhal. Este estudo caracteriza os achados clínicos, tomográficos e de necropsia de um neonato Nelore dicefálico.
ABSTRACT This study aimed to evaluate copper sulfate solutions at 5% and 10% concentrations in footbaths from three dairy farms (A, B and C) with free stall and compost barn production systems, ...located in the municipality of Arapoti, Parana, Brazil. Farms A, B and C were composed of 537, 88 and 208 lactating cows, respectively, all conditioned to the use of a footbath. Every seven days, before and after the passage of each batch of cows through the footbath, samples of the solution were collected for the evaluation of pH, temperature, and the volume of the solution measured. Farms A and C had higher pH alkalinization due to the greater number of batch passages, from the third batch onwards, and also a reduction in the volume of the solution. It is concluded that the volume varied both with the number of animals that passed through the footbath and with the deposition of organic matter in the solution. The concentration of 10% copper sulfate solution was not able to inhibit pH changes. Furthermore, there was no standardization in the dimensions of the footbaths on the farms.
RESUMO Objetivou-se avaliar as soluções de sulfato de cobre nas concentrações de 5% e 10%, em pedilúvios de três propriedades leiteiras (A, B e C), com sistemas de produção “free stall” e “compost barn”, localizadas no município de Arapoti, Paraná, Brasil. As propriedades A, B e C eram compostas por 537, 88 e 208 vacas em lactação, respectivamente, todas condicionadas ao uso do pedilúvio. A cada sete dias, antes e após a passagem de cada lote de vacas pelo pedilúvio, foram colhidas amostras da solução para a avaliação do pH, da temperatura e do volume. As propriedades A e C tiveram alcalinização maior do pH devido ao maior número de passagem de lotes, a partir do terceiro lote, com redução também do volume da solução. Conclui-se que o volume variou tanto com o número de animais que passaram pelo pedilúvio quanto com a deposição de matéria orgânica na solução. A concentração da solução de sulfato de cobre a 10% não foi capaz de inibir as alterações de pH. Além disso, não houve padronização das dimensões dos pedilúvios nas fazendas.
Bayesian model averaging in EEG/MEG imaging Trujillo-Barreto, Nelson J.; Aubert-Vázquez, Eduardo; Valdés-Sosa, Pedro A.
NeuroImage,
04/2004, Letnik:
21, Številka:
4
Journal Article
Recenzirano
Odprti dostop
In this paper, the Bayesian Theory is used to formulate the Inverse Problem (IP) of the EEG/MEG. This formulation offers a comparison framework for the wide range of inverse methods available and ...allows us to address the problem of model uncertainty that arises when dealing with different solutions for a single data. In this case, each model is defined by the set of assumptions of the inverse method used, as well as by the functional dependence between the data and the Primary Current Density (PCD) inside the brain. The key point is that the Bayesian Theory not only provides for posterior estimates of the parameters of interest (the PCD) for a given model, but also gives the possibility of finding posterior expected utilities unconditional on the models assumed. In the present work, this is achieved by considering a third level of inference that has been systematically omitted by previous Bayesian formulations of the IP. This level is known as Bayesian model averaging (BMA). The new approach is illustrated in the case of considering different anatomical constraints for solving the IP of the EEG in the frequency domain. This methodology allows us to address two of the main problems that affect linear inverse solutions (LIS): (a) the existence of ghost sources and (b) the tendency to underestimate deep activity. Both simulated and real experimental data are used to demonstrate the capabilities of the BMA approach, and some of the results are compared with the solutions obtained using the popular low-resolution electromagnetic tomography (LORETA) and its anatomically constraint version (cLORETA).
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