Structural and functional connectivity changes in response to short-term neurofeedback training with motor imagery.

Recent findings have been challenging current understanding of how fast the human brain change its structural and functional connections in response to training. One powerful way to deepen the inner workings of human brain plasticity is using neurofeedback (NFB) by fMRI, a technique that allows self-induced brain plasticity by means of modulating brain activity in real time. In the present randomized, double-blind and sham-controlled study, we use NFB to train healthy individuals to reinforce brain patterns related to motor execution while performing a motor imagery task, with no overt movement. After 1 h of NFB training, participants displayed increased fractional anisotropy (FA) in the sensorimotor segment of corpus callosum and increased functional connectivity of the sensorimotor resting state network. Increased functional connectivity was also observed in the default mode network. These results were not observed in the control group, which was trained with sham feedback. To our knowledge, this is the first demonstration of white matter FA changes following a very short training schedule (<1 h). Our results suggest that NFB by fMRI can be an interesting tool to explore dynamic aspects of brain plasticity and open new venues for investigating brain plasticity in healthy individuals and in neurological conditions.

Motor planning of goal-directed action is tuned by the emotional valence of the stimulus: a kinematic study.

The basic underpinnings of homeostatic behavior include interacting with positive items and avoiding negative ones. As the planning aspects of goal-directed actions can be inferred from their movement features, we investigated the kinematics of interacting with emotion-laden stimuli. Participants were instructed to grasp emotion-laden stimuli and bring them toward their bodies while the kinematics of their wrist movement was measured. The results showed that the time to peak velocity increased for bringing pleasant stimuli towards the body compared to unpleasant and neutral ones, suggesting higher easiness in undertaking the task with pleasant stimuli. Furthermore, bringing unpleasant stimuli towards the body increased movement time in comparison with both pleasant and neutral ones while the time to peak velocity for unpleasant stimuli was the same as for that of neutral stimuli. There was no change in the trajectory length among emotional categories. We conclude that during the "reach-to-grasp" and "bring-to-the-body" movements, the valence of the stimuli affects the temporal but not the spatial kinematic features of motion. To the best of our knowledge, we show for the first time that the kinematic features of a goal-directed action are tuned by the emotional valence of the stimuli.

Sorovares e perfil de suscetibilidade a antimicrobianos em Salmonella spp. isoladas de produtos de origem suína / Serovars and antimicrobial susceptibility of Salmonella spp. product isolated from swine

Foi analisado um total de 1824 cepas de Salmonella, isoladas de alimentos de origem suína, no período de janeiro/2005 a junho/2010. As cepas, provenientes de diferentes regiões do país, foram recebidas pelo Labent/IOC/FIocruz para caracterização antigênica conclusiva. Foram identificados 41 sorovares, destacando-se: Typhimurium, Derby, Enteritidis, Panama, Infantis e Anatum. Aspectos bacteriológicos e epidemiológicos relacionados a esses sorovares foram discutidos. O teste de suscetibilidade aos antimicrobianos foi realizado em 357 amostras, 257 (72%) foram resistentes a uma ou mais drogas, e destas, 31,9% mostraram-se multirresistentes. A variedade de sorovares observada neste estudo confirma o papel dos suínos na cadeia alimentar como importantes reservatórios de Salmonella, agravado ainda pelo elevado percentual de cepas resistentes a um ou mais antimicrobianos, alertando para uma condição de risco à saúde pública.

We analyzed a total of 1824 strains of Salmonella isolated from swine-origin foods from January/2005 to June/2010. The strains from different regions of the country were received by Labent/IOC/FIOCRUZ for conclusive antigenic characterization. We identified 41 serovars, of which these stood out: Typhimurium, Derby, Enteritidis, Panama, Infantis and Anatum. Bacteriological and epidemiological aspects related to these serovars were discussed. The antimicrobial susceptibility test was performed on 357 samples, 257 (72%) were resistant to one or more of these drugs and 31,9% were multiresistant. A variety of serovars were identified reinforcing the swine as an important reservoir of Salmonella in the food chain. The high rates of antimicrobial resistance obtained in this evaluation may represent a risk condition to human health.

Study of the utilization of light egg-type males: a proposal for the sustainability of the egg industry.

This study evaluated the performance and viability of light egg-type males, usually euthanized at the hatcheries, from White and Brown Leghorn laying hen lines. One-day-old male chicks, half from each hen line, were raised in floor pens until they were 42 d of age. The birds were distributed into 48 floor pens, furnished with tube feeders and nipple drinkers, and submitted to 24 h of continuous light, 3 feeding phases (1-7, 8-21, and 22-42 d) and diets composed of corn and soybean meal as the main ingredients. A completely randomized design was used in a 4 × 2 factorial arrangement (phase levels of ME dietary treatments × strain) of 6 replicates of 40 birds each. The variables evaluated were bird performance, carcass quality, and yield at 42 d of age. Mortality and cannibalism were not observed during the entire experimental period, although the birds' beaks were not trimmed. The brown males line showed higher feed consumption and BW gain and better feed conversion compared with the white male line (P< 0.05). Metabolizable energy (kcal/kg) levels of 3,200 (1 to 7 d), 3,050 (8 to 21 d), and 3,200 (22 to 42 d) provided better performance (P< 0.05) in both lines. The carcass yields were similar (P> 0.05) between the 2 lines; males from the white line showed higher breast yield, and the brown line males showed higher yield of thighs and drumstick (P< 0.05). The treatments had no effect on meat quality (P > 0.05). Overall, the results suggest that there is great viability for the use of male chicks from laying hens of both leghorn lines as a high quality protein source for human consumption.

Heterosis for meat quality and fatty acid profiles in crosses among Bos indicus and Bos taurus finished on pasture or grain.

Physicochemical properties and fatty acid profiles of meat from Bos indicus, Bos taurus and crossbred B. taurus×B. indicus bullocks (n=216), finished on pasture or grain, were used to estimate the effects of heterosis. Meat quality and fatty acid profiles generally benefited with crossbreeding, but the advantages from heterosis differed among finishing systems. The Warner-Bratzler shear-force in fresh and aged meat was reduced due to heterosis in pasture-finishing, but the effect was minor under grain-finishing. With pasture-finishing, heterosis caused an increase of 5% in CLA concentration, but few other changes in fatty acid profiles. In grain-finishing, heterosis caused a reduction in intramuscular fat and cholesterol, increased amounts of PUFA, n-6 fatty acids and PUFA/SFA ratio, and a decline in atherogenic index. The Δ(9) desaturase estimated activity in crossbreds showed a behavior close to B. indicus, suggesting the existence of few loci and a dominance genetic effect on enzymes involved in fatty acid synthesis and metabolism.

Role of the parietal cortex in predicting incoming actions.

Animal and human studies have shown that the parietal and the ventral premotor cortices constitute the neural substrate of the so-called mirror system. The word "mirror" originally referred to the discovery of neurons in non-human primates whose visual response echoes their motor response. This account proposes that action understanding and imitation depend on a mechanism which activates directly our own motor system as we observe the actions of other agents (Rizzolatti and Sinigaglia, 2010). Single unit recording experiments have also demonstrated that parietal neurons have predictive activity and discharge well ahead of a planned movement. Interestingly, patients with parietal damage can show impairments in their ability to imitate or understand an observed action, but they have also difficulties in monitoring early phases of their own movement planning, be it simple reaching movements or more complex object-directed actions. The fact that both deficits may co-occur after a parietal lesion raises the question whether this reflects the impairment of a common mechanism. To address this question we examined EEG activity in patients with selective lesions in the inferior parietal lobe (N=6) who were requested to watch passively a video showing an actor grasping a colored object. The object's color cued the subject that the actor was about to move. We recorded the Readiness Potential (RP), a marker of motor preparation which also arises when preparing to observe an action (Kilner et al., 2004). Parietal patients' performance was compared to that of neurologically normal subjects (n=9) and patients with a ventral premotor cortex lesion (N=4). We show that neurologically normal subjects and premotor patients exhibit a significant RP prior to the observed action, whereas no such RP is observed in parietal patients. Our results indicate that parietal cortex injury alters the ability to monitor the early planning phases not only of one's own actions but those of other agents as well. We speculate that parietal activity during action observation does not only or essentially reflect a mirroring process, as recently proposed by mirror neurons' account, but involve instead an anticipatory process which arises through prior learning and predictive mechanisms.

Genotype x environment interactions for fatty acid profiles in Bos indicus and Bos taurus finished on pasture or grain.

A study was conducted to characterize lipid profiles in the M. longissimus thoracis of commercial Brazilian beef and to assess how those profiles are influenced by finishing system, genetic group, and their interaction. Intramuscular fat (IMF) and fatty acid (FA) profiles were determined in 160 bulls of the Bos taurus (n = 75) and Bos indicus (n = 85) genetic groups, finished on pasture (n = 46) or with grain supplementation (n = 114) and slaughtered in a commercial abattoir. Finishing system had a major impact on the deposition of IMF, as well as on the concentration of SFA, PUFA, and their ratio, but genetic groups showed important differences in the ability to convert SFA into cis-9 MUFA and to convert 16:0 into 18:0. When compared with pasture-finished animals, those finished with grain had greater content of IMF and SFA (P < 0.01), similar amounts of MUFA (P > 0.05), and about one-half the amount of PUFA (P < 0.01). Except for MUFA, differences in FA profiles among finishing systems were mostly mediated through their effect on IMF, even though the relationship of IMF with groups of FA differed among finishing systems. Under grain finishing, B. taurus had less SFA and greater MUFA than B. indicus (P < 0.01), but no differences were observed in PUFA (P > 0.05). With pasture-finishing, no differences were observed among the 2 genetic groups in SFA and MUFA (P > 0.05), but PUFA were decreased in B. taurus (P < 0.01). When genetic groups were compared in grain-finishing, B. taurus had a decreased ability for elongation and B. indicus had a decreased aptitude for desaturation of FA. On the other hand, with pasture-finishing a greater deposition of intermediate FA from ruminal biohydrogenation was observed in B. indicus than in B. taurus. Overall, FA profiles were affected more by finishing system in B. indicus than in B. taurus.

Kinesthetic motor imagery modulates body sway.

The aim of this study was to investigate the effect of imagining an action implicating the body axis in the kinesthetic and visual motor imagery modalities upon the balance control system. Body sway analysis (measurement of center of pressure, CoP) together with electromyography (EMG) recording and verbal evaluation of imagery abilities were obtained from subjects during four tasks, performed in the upright position: to execute bilateral plantar flexions; to imagine themselves executing bilateral plantar flexions (kinesthetic modality); to imagine someone else executing the same movement (visual modality), and to imagine themselves singing a song (as a control imagery task). Body sway analysis revealed that kinesthetic imagery leads to a general increase in CoP oscillation, as reflected by an enhanced area of displacement. This effect was also verified for the CoP standard deviation in the medial-lateral direction. An increase in the trembling displacement (equivalent to center of pressure minus center of gravity) restricted to the anterior-posterior direction was also observed to occur during kinesthetic imagery. The visual imagery task did not differ from the control (sing) task for any of the analyzed parameters. No difference in the subjects' ability to perform the imagery tasks was found. No modulation of EMG data were observed across imagery tasks, indicating that there was no actual execution during motor imagination. These results suggest that motor imagery performed in the kinesthetic modality evokes motor representations involved in balance control.

[Food borne disease outbreaks caused by Salmonella enteritidis]. / Surtos de enfermidades transmitidas por alimentos causados por Salmonella enteritidis.

OBJECTIVE: It is to describe outbreaks of salmonellosis reported from July 1993 through June 1997 in the Northwest region of S. Paulo State, Brazil, one of the areas where several foodborne outbreaks of salmonellosis have been recently detected. METHOD: Data of 19 epidemiological investigations were analysed; 87 stool specimens and 38 food samples (including 12 of shell eggs) were processed for microbiological analysis. Salmonella strains were identified by serotyping, phagetyping and antimicrobial susceptibility testing. RESULTS: There were 906 ill persons including 295 hospitalized patients. Phage type 4 (PT 4) Salmonella Enteritidis strains were isolated from 80.5% of stool samples, from all food samples and from 41.7% of eggs. Of the outbreaks, 95.7% were associated with the consumption of food containing raw or undercooked eggs. All strains were susceptible to the 13 antimicrobials, except the strains from the nosocomial outbreak. CONCLUSIONS: The results obtained show the need for the implementation of control measures regarding egg and storage, as well as for guidance to the public as to the risks involved in the consumption of inadequately prepared eggs.

Observaçöes citológicas em conídios e células miceliais de humicola sp / Cytological observations in conidial and mycelial cells of humicola sp

Resumo: O objetivo desse estudo foi descrever aspectos do comportamento nuclear durante a divisäo miótica em conídios e células miceliais do fungo celulolítico Humicola so. A sequência dos eventos mitóticos foi similar aquela observada em outros fungos filamentosos. O número de cromossomos observados no final da metáfase näo pode ser determinado com segurança, mas pareceu estar entre 6 e 8. As culturas de Humicola sp frequentemente mostraram anastomose de hifas e a presença de núcleos na ponte hifal, o que permitiria a ocorrência de heterocariose,e indica que o ciclo parasexual pode ocorrer nessa espécie (au)

[Prevalence of virus B infection in a hospital community]. / Prevalência da infecção pelo vírus B na comunidade hospitalar.

The authors studied the prevalence of HBV markers among health care personnel of the University Hospital of the Federal University of Rio de Janeiro. The aim of study was to identify the high risk groups, in order to counsel vaccination of those groups, in order to counsel vaccination of those groups at risk as a routine. As a control group, a group of office workers of the hospital were chosen. A significant difference of incidence of HBV markers, mainly in surgeons (40%) and hemodialysis unit personnel (36.4%) when compared to the control group, was observed (p less than 0.05). The incidence increased with age and the time spent in the profession. The authors concluded that vaccination is indicated in surgeons hemodialysis personnel, dentists and laboratory personnel.