Conspecific and heterospecific alarm substance induces behavioral responses in piau fish Leporinus piau

In ostariophysan fish, the detection of alarm substance released from the skin of a conspecific or a sympatric heterospecific may elicit alarm reactions or antipredator behavioral responses. In this study, experiments were performed to characterize and quantify the behavioral response threshold of Leporinus piau, both individually and in schools, to growing dilutions of conspecific (CAS) and heterospecific skin extract (HAS). The predominant behavioral response to CAS stock stimulation was biphasic for fish held individually, with a brief initial period of rapid swimming followed by a longer period of immobility or reduced swimming activity. As the dilution of skin extract was increased, the occurrence and magnitude of the biphasic alarm response tended to decrease, replaced by a slowing of locomotion. Slowing was the most common antipredator behavior, observed in 62.5% of animals submitted to HAS stimulation. School cohesion, measured as proximity of fish to the center of the school, and swimming activity near the water surface significantly increased after exposure to CAS when compared with the control group exposed to distilled water. Histological analysis of the epidermis revealed the presence of Ostariophysi-like club cells. The presence of these cells and the behavioral responses to conspecific and heterospecific skin extract stimulation suggest the existence of a pheromone alarm system in L. piau similar to that in Ostariophysi, lending further support for the neural processing of chemosensory information in tropical freshwater fish.

The A61 G EGF polymorphism is associated with development of extraaxial nervous system tumors but not with overall survival

Epidermal growth factor can activate several signaling pathways, leading to proliferation, differentiation, and tumorigenesis of epithelial tissues by binding with its receptor. The EGF protein is involved in nervous system development, and polymorphisms in the EGF gene on chromosome band 4q25 are associated with brain cancers. The purpose of this study was to investigate the association between the single-nucleotide polymorphism of EGF + 61 G/A and extraaxial brain tumors in a population of the southeast of Brazil. We analyzed the genotype distribution of this polymorphism in 90 patients and 100 healthy subjects, using the polymerase chain reaction restriction fragment length polymorphism technique. Comparison of genotype distribution revealed a significant difference between patients and control subjects (P < 0.001). The variant genotypes of A/G and G/G were associated with a significant increase of the risk of tumor development, compared with the homozygote A/A (P < 0.0001). When the analyses were stratified, we observed that the genotype GIG was more frequent in female patients (P = 0.021). The same genotype was observed more frequently in patients with low-grade tumors (P = 0.001). Overall survival rates did not show statistically significant differences. Our data suggest that the EGF A61 G polymorphism can be associated with susceptibility to development of these tumors. (C) 2010 Elsevier Inc. All rights reserved.

Effects of the levonorgestrel-releasing intrauterine system on cardiovascular risk markers in patients with endometriosis: a comparative study with the GnRH analogue

Background: The study was conducted to evaluate the cardiovascular risk markers associated with endometriosis and the influence of the levonorgestrel intrauterine system (LNG-TUS) compared with the GnRH analogue (GnRHa) leuprolide acetate on these risk markers after 6 months of treatment. Study Design: This was a randomized, prospective, open clinical Study, with 44 patients with laparoscopically and histologically confirmed endometriosis. Patients were randomized into two groups: the LNG-IUS group, composed of 22 patients who underwent LNG-IUS insertion., and the GnRHa group, composed of 22 patients who received a monthly GnRHa injection for 6 months. Body mass index systolic and diastolic arterial blood pressure; heart rate; and laboratory cardiovascular risk markers such as interlelikin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), C-reactive protein (CRP), homocysteine (HMC), lipid profile, total leukocytes and vascular cell adhesion molecule (VCAM) were measured before and 6 months after treatment. Results: After 6 months of treatment, a significant reduction in pain score occurred in both groups with no significant difference in improvement between the two medications evaluated. In the LNG-IUS group, from pretreatment to posttreatment period, there was a significant reduction in the levels (mean +/- SD) of VCAM (92.8 +/- 4.2 to 91.2 +/- 2.7 ng/mL, p=.04), CRP (0.38 +/- 0.30 to 0.28 +/- 0.21 mg/dL, p=.03), total cholesterol (247.0 +/- 85.0 to 180.0 +/- 31.0 mg/dL, p=.0002), triglycerides (118.0 +/- 76.0 to 86.5 +/- 41.5 mg/dL, p=.003), low-density lipoprotein cholesterol (160.5 +/- 66.0 to 114.5 +/- 25.5 mg/dL, p=.0005) and high-density lipoprotein cholesterol (63.0 +/- 20.5 to 48.5 +/- 10.5 mg/dL, p=.002). The GnRHa group showed an increase in HMC levels (11.5 +/- 2.9 to 13.0 +/- 2.7 mu mol/L, p=.04) and a reduction in IL-6 levels (4.3 +/- 3.9 to 2.3 +/- 0.8 pg/mL, p=.005), VCAM (94.0 +/- 3.8 to 92.0 +/- 1.6 ng/mL, p=.03) and total leukocytes (7330 +/- 2554 to 6350 +/- 1778, p=.01). In the GnRH group, the remaining variables, including lipid profile, did not show any statistical difference. Conclusions: This study shows that some cardiovascular risk markers are influenced by both GnRHa and the LNG-TUS, but the latter had a greater positive impact on the lipid profile, which could lead to a favorable effect during long-term treatment. (C) 2010 Elsevier Inc. All rights reserved.

A Dynamical Modeling to Study the Adaptive Immune System and the Influence of Antibodies in the Immune Memory

Immunological systems have been an abundant inspiration to contemporary computer scientists. Problem solving strategies, stemming from known immune system phenomena, have been successfully applied to chall enging problems of modem computing. Simulation systems and mathematical modeling are also beginning use to answer more complex immunological questions as immune memory process and duration of vaccines, where the regulation mechanisms are not still known sufficiently (Lundegaard, Lund, Kesmir, Brunak, Nielsen, 2007). In this article we studied in machina a approach to simulate the process of antigenic mutation and its implications for the process of memory. Our results have suggested that the durability of the immune memory is affected by the process of antigenic mutation.and by populations of soluble antibodies in the blood. The results also strongly suggest that the decrease of the production of antibodies favors the global maintenance of immune memory.

Multi-system neurological disease is common in patients with OPA1 mutations

Additional neurological features have recently been described in seven families transmitting pathogenic mutations in OPA1, the most common cause of autosomal dominant optic atrophy. However, the frequency of these syndromal `dominant optic atrophy plus` variants and the extent of neurological involvement have not been established. In this large multi-centre study of 104 patients from 45 independent families, including 60 new cases, we show that extra-ocular neurological complications are common in OPA1 disease, and affect up to 20% of all mutational carriers. Bilateral sensorineural deafness beginning in late childhood and early adulthood was a prominent manifestation, followed by a combination of ataxia, myopathy, peripheral neuropathy and progressive external ophthalmoplegia from the third decade of life onwards. We also identified novel clinical presentations with spastic paraparesis mimicking hereditary spastic paraplegia, and a multiple sclerosis-like illness. In contrast to initial reports, multi-system neurological disease was associated with all mutational subtypes, although there was an increased risk with missense mutations [odds ratio = 3.06, 95% confidence interval = 1.44-6.49; P = 0.0027], and mutations located within the guanosine triphosphate-ase region (odds ratio = 2.29, 95% confidence interval = 1.08-4.82; P = 0.0271). Histochemical and molecular characterization of skeletal muscle biopsies revealed the presence of cytochrome c oxidase-deficient fibres and multiple mitochondrial DNA deletions in the majority of patients harbouring OPA1 mutations, even in those with isolated optic nerve involvement. However, the cytochrome c oxidase-deficient load was over four times higher in the dominant optic atrophy + group compared to the pure optic neuropathy group, implicating a causal role for these secondary mitochondrial DNA defects in disease pathophysiology. Individuals with dominant optic atrophy plus phenotypes also had significantly worse visual outcomes, and careful surveillance is therefore mandatory to optimize the detection and management of neurological disability in a group of patients who already have significant visual impairment.

Involvement of the central nervous system in the chronic form of Chagas` disease

Background and purpose: Apart from the central nervous system parasitic invasion in chagasic immunodeficient patients and strokes due to heart lesions provoked by the disease, the typical neurological syndromes of the chronic phase of Chagas` disease (CD) have not yet been characterized, although involvement of the peripheral nervous system has been well documented. This study aims at investigating whether specific signs of central nervous system impairment might be associated with the disease. Methods: Twenty-seven patients suffering from the chronic form of Chagas` disease (CCD) and an equal number of controls matched for sex, age, educational and socio-cultural background, and coming from the same geographical regions, were studied using neurological examinations, magnetic resonance images, and electroencephalographic frequency analysis. Results: Nineteen patients were at the stage A of the cardiac form of the disease (without documented structural lesions or heart failure). Dizziness, brisk reflexes, and ankle and knee areflexia were significantly more prevalent in the patients than in the controls. The significant findings in quantitative electroencephalogram were an increase in the theta relative power and a decrease in the theta dominant frequency at temporal-occipital derivations. Subcortical, white matter demyelination was associated with diffuse theta bursts and theta-delta slowing in two patients. Conclusions: Our findings suggest a discrete and unspecific functional cortical disorder and possible white matter lesions in CD. The focal nervous system abnormalities in CD documented here did not seem to cause significant functional damage or severely alter the patient`s quality of life. (C) 2008 Elsevier B.V. All rights reserved.

Organophosphate-related ototoxicity: Description of the vestibulocochlear system ultrastructural aspects of guinea pigs

Organophosphate toxic agents are used in agriculture and are currently part of the group of toxic agents which can lead to hearing loss, in which we have solvents, metals and asphyxiation agents. Aim: to analyze the acute ototoxic action of a group of organophosphate agents in the vestibulocochlear system. This is a prospective experimental study. Materials and Methods: we used male albino guinea pigs, broken down into three groups, to which we provided distilled water (group 1 - control), agrotoxic agent - 0.3mg/Kg/day (group 2), agrotoxic - 3 mg/Kg/day (group 3), during 7 seven consecutive days. The most used agrotoxic agent was Tamaron BR (metamidophos). The anatomical evaluation of the cochlea, saccule and utricle was carried out by means of electronic scanning microscopy after the use of the agrotoxic agent. Results: the guinea pigs submitted to the organophosphate presented cochlear morphological alterations with lesions on the three turns analyzed, as well as cilia alterations in the saccule and utricle, intensified according to the agent dosage. Conclusion: the morphological alterations seen in the hair cells exposed to daily doses of organophosphate promote evidences of an acute deleterious effect of agrotoxic agents on the vestibulocochlear system.

The relationship between two types of upper eyelid movements: Saccades and pursuit

PURPOSE. To establish the relationship between upper eyelid saccades and upper eyelid pursuit movements. METHODS. Upper eyelid saccades and periodic sinusoidal upper eyelid pursuit movements were recorded in a sample of controls and patients with Graves upper eyelid retraction. A video-computerized system was used to register both types of movements that accompanied 60 of eye rotation across the upper and lower hemifields. The forced harmonic oscillator model was used to fit saccadic and pursuit movements. RESULTS. Mean mid-pupil eyelid distance for the Graves patients (6.6 +/- 1.1 mm) was significantly higher than for the controls (4.6 +/- 0.8 mm; t = 7.18; P < 0.00001). Despite the difference in the upper eyelid resting position, saccades and pursuit eyelid movements of both groups were extremely well fitted by underdamped solutions and steady forced solutions of the harmonic oscillator model, respectively. For the controls, the amplitude of the pursuit movements was well correlated with the upward and downward saccades. The amplitude of the eyelid movements of the Graves patients (saccades and pursuit) was significantly reduced compared with that of the controls. CONCLUSIONS. Saccadic and pursuit movements of the upper eyelid can be described by the harmonic oscillator model. In healthy subjects and Graves patients, the amplitude of pursuit lid movements is correlated to the saccade amplitude. Pursuit eyelid movements are more difficult to register than saccades, and their measurements do not allow clear separation of the relaxation and contraction properties of the upper eyelid retractors.

Is dystonic posturing during temporal lobe epileptic seizures the expression of an endogenous anticonvulsant system?

In temporal lobe epilepsy (TLE) seizures, tonic or clonic motor behaviors (TCB) are commonly associated with automatisms, versions, and vocalizations, and frequently occur during secondary generalization. Dystonias are a common finding and appear to be associated with automatisms and head deviation, but have never been directly linked to generalized tonic or clonic behaviors. The objective of the present study was to assess whether dystonias and TCB are coupled in the same seizure or are associated in an antagonistic and exclusive pattern. Ninety-one seizures in 55 patients with TLE due to mesial temporal sclerosis were analyzed. Only patients with postsurgical seizure outcome of Engel class I or II were included. Presence or absence of dystonia and secondary generalization was recorded. Occurrence of dystonia and occurrence of bilateral tonic or clonic behaviors were negatively correlated. Dystonia and TCB may be implicated in exclusive, non-coincidental, or even antagonistic effects or phenomena in TLE seizures. A neural network related to the expression of one behavioral response (e.g., basal ganglia activation and dystonia) might theoretically ""displace"" brain activation or disrupt the synchronism of another network implicated in pathological circuit reverberation and seizure expression. The involvement of basal ganglia in the blockade of convulsive seizures has long been observed in animal models. The question is: Do dystonia and underlying basal ganglia activation represent an attempt of the brain to block imminent secondary generalization? (C) 2007 Elsevier Inc. All rights reserved.

Assessment of synovitis with contrast-enhanced MRI using a whole-joint semiquantitative scoring system in people with, or at high risk of, knee osteoarthritis: the MOST study

Objectives To introduce a comprehensive and reliable scoring system for the assessment of whole-knee joint synovitis based on contrast-enhanced (CE) MRI. Methods Multicenter Osteoarthritis Study (MOST) is a cohort study of people with, or at high risk of, knee osteoarthritis (OA). Subjects are an unselected subset of MOST who volunteered for CE-MRI. Synovitis was assessed at 11 sites of the joint. Synovial thickness was scored semiquantitatively: grade 0 (< 2 mm), grade 1 (2-4 mm) and grade 2 (> 4 mm) at each site. Two musculoskeletal radiologists performed the readings and inter-and intrareader reliability was evaluated. Whole-knee synovitis was assessed by summing the scores from all sites. The association of Western Ontario and McMaster Osteoarthritis Index pain score with this summed score and with the maximum synovitis grade for each site was assessed. Results 400 subjects were included (mean age 58.8 +/- 7.0 years, body mass index 29.5 +/- 4.9 kg/m(2), 46% women). For individual sites, intrareader reliability (weighted kappa) was 0.67-1.00 for reader 1 and 0.60-1.00 for reader 2. Inter-reader agreement (kappa) was 0.67-0.92. For the summed synovitis scores, intrareader reliability (intraclass correlation coefficient (ICC)) was 0.98 and 0.96 for each reader and inter-reader agreement (ICC) was 0.94. Moderate to severe synovitis in the parapatellar subregion was associated with the higher maximum pain score (adjusted OR (95% CI), 2.8 (1.4 to 5.4) and 3.1 (1.2 to 7.9), respectively). Conclusions A comprehensive semiquantitative scoring system for the assessment of whole-knee synovitis is proposed. It is reliable and identifies knees with pain, and thus is a potentially powerful tool for synovitis assessment in epidemiological OA studies.

Analysis of the Ontogenetic Variation in the Venom Proteome/Peptidome of Bothrops jararaca Reveals Different Strategies to Deal with Prey

Previous studies have demonstrated that the pharmacological activities displayed by Bothrops jararaca venom undergo a significant ontogenetic shift. Variation in the venom proteome is a well-documented phenomenon; however, variation in the venom peptidome is poorly understood. We report a comparative proteomic and peptidomic analysis of venoms from newborn and adult specimens of B. jararaca and correlate it with the evaluation of important venom features. We demonstrate that newborn and adult venoms have similar hemorrhagic activities, while the adult venom has a slightly higher lethal activity in mice; however, the newborn venom is extremely more potent to kill chicks. The coagulant activity of newborn venom upon human plasma is 10 times higher than that of adult venom. These differences were clearly reflected in their different profiles of SDS-PAGE, gelatin zimography, immunostaining using specific antibodies, glycosylation pattern, and concanavalin A-binding proteins. Furthermore, we report for the first time the analysis of the peptide fraction of newborn and adult venoms by MALDI-TOF mass spectrometry and LC-MS/MS, which revealed different contents of peptides, while the bradykinin potentiating peptides (BPPs) showed rather similar profiles and were detected in the venoms showing their canonical sequences and also novel sequences corresponding to BPPs processed from their precursor protein at sites so far not described. As a result of these studies, we demonstrated that the ontogenetic shift in diet, from ectothermic prey in early life to endothermic prey in adulthood, and in animal size are associated with changes in the venom proteome in B. jararaca species.

Substitution of crude cell wall for neutral detergent fibre in the equations of the Cornell Net Carbohydrate and Protein System that predict carbohydrate fractions: application to sunflower (Helianthus annulus L.)

Prediction of carbohydrate fractions using equations from the Cornell Net Carbohydrate and Protein System (CNCPS) is a valuable tool to assess the nutritional value of forages. In this paper these carbohydrate fractions were predicted using data from three sunflower (Helianthus annuus L.) cultivars, fresh or as silage. The CNCPS equations for fractions B(2) and C include measurement of ash and protein-free neutral detergent fibre (NDF) as one of their components. However, NDF lacks pectin and other non-starch polysaccharides that are found in the cell wall (CW) matrix, so this work compared the use of a crude CW preparation instead of NDF in the CNCPS equations. There were no differences in the estimates of fractions B, and C when CW replaced NDF; however there were differences in fractions A and B2. Some of the CNCPS equations could be simplified when using CW instead of NDF Notably, lignin could be expressed as a proportion of DM, rather than on the basis of ash and protein-free NDF, when predicting CNCPS fraction C. The CNCPS fraction B(1) (starch + pectin) values were lower than pectin determined through wet chemistty. This finding, along with the results obtained by the substitution of CW for NDF in the CNCPS equations, suggests that pectin was not part of fraction B(1) but present in fraction A. We suggest that pectin and other non-starch polysaccharides that are dissolved by the neutral detergent solution be allocated to a specific fraction (B2) and that another fraction (B(3)) be adopted for the digestible cell wall carbohydrates.

Modeling the Competition Between Viruses in a Complex Plant-Pathogen System

In this article, we propose a mathematical model that describes the competition between two plant virus strains (MAV and PAV) for both the host plant (oat) and their aphid vectors. We found that although PAV is transmitted by two aphids and MAV by only one, this fact, by itself, does not explain the complete replacement of MAV by PAV in New York State during the period from 1961 through 1976; an interpretation that is in agreement with the theories of A. G. Power. Also, although MAV wins the competition within aphids, we assumed that, in 1961, PAV mutated into a new variant such that this new variant was able to overcome MAV within the plants during a latent period. As shown below, this is sufficient to explain the swap of strains; that is, the dominant MAV was replaced by PAV, also in agreement with Power`s expectations.

The GABAergic system contributes to the anxiolytic-like effect of essential oil from Cymbopogon citratus (lemongrass)

Ethnopharmacological relevance: The essential oil (EO) from Cymbopogon citratus (DC) Stapf is reported to have a wide range of biological activities and is widely used in traditional medicine as an infusion or decoction. However, despite this widely use, there are few controlled studies confirming its biological activity in central nervous system. Materials and methods: The anxiolytic-like activity of the EO was investigated in light/dark box (LDB) and marble-burying test (MBT) and the antidepressant activity was investigated in forced-swimming test (FST) in mice. Flumazenil, a competitive antagonist of benzodiazepine binding and the selective 5-HT(1A) receptor antagonist WAY100635 was used in experimental procedures to determine the action mechanism of EO. To exclude any false positive results in experimental procedures, mice were submitted to the rota-rod test. We also quantified some neurotransmitters at specific brain regions after EO oral acute treatment. Results: The present work found anxiolytic-like activity of the EO at the dose of 10 mg/kg in a LDB. Flumazenil, but not WAY100635, was able to reverse the effect of the EO in the LOB, indicating that the EO activity occurs via the GABA(A) receptor-benzodiazepine complex. Only at higher doses did the EO potentiate diethyl-ether-induced sleeping time in mice. In the FST and MBT, EO showed no effect. Finally, the increase in time spent in the light chamber, demonstrated by concomitant treatment with ineffective doses of diazepam (DZP) and the EO, revealed a synergistic effect of the two compounds. The lack of activity after long-term treatment in the LDB test might be related to tolerance induction, even in the DZP-treated group. Furthermore, there were no significant differences between groups after either acute or repeated treatments with the EO in the rota-rod test. Neurochemical evaluation showed no amendments in neurotransmitter levels evaluated in cortex, striatum, pons, and hypothalamus. Conclusions: The results corroborate the use of Cymbopogon citratus in folk medicine and suggest that the anxiolytic-like effect of its EO is mediated by the GABA(A) receptor-benzodiazepine complex. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

Behavior: A Relevant Tool for Brain-immune System Interaction Studies

Neuroimmunomodulation describes the field focused on understanding the mechanisms by which the central nervous system interacts with the immune system, potentially leading to changes in animal behavior. Nonetheless, not many articles dealing with neuroimmunomodulation employ behavior as an analytical endpoint. Even fewer papers deal with social status as a possible modifier of neuroimmune phenomena. In the described sets of experiments, we tackle both, using a paradigm of social dominance and subordination. We first review data on the effects of different ranks within a stable hierarchical relationship. Submissive mice in this condition display more anxiety-like behaviors, have decreased innate immunity, and show a decreased resistance to implantation and development of melanoma metastases in their lungs. This suggests that even in a stable, social, hierarchical rank, submissive animals may be subjected to higher levels of stress, with putative biological relevance to host susceptibility to disease. Second, we review data on how dominant and submissive mice respond differentially to lipopolysaccharide (LPS), employing a motivational perspective to sickness behavior. Dominant animals display decreased number and frequency in several aspects of behavior, particularly agonistic social interaction, that is, directed toward the submissive cage mate. This was not observed in submissive mice that maintained the required behavior expected by its dominant mate. Expression of sickness behavior relies on motivational reorganization of priorities, which are different along different social ranks, leading to diverse outcomes. We suggest that in vitro assessment of neuroimmune phenomena can only be understood based on the behavioral context in which they occur.