990 resultados para Locomotor sensitization


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Pharmacological treatments currently used in ethanol addiction are inefficient, requiring new drugs for this purpose. The pro-drug N-Acetylcysteine (N-Ac) has shown efficacy in the treatment of addiction to cocaine and nicotine in preclinical research and clinical pilot studies. When administered, N-Ac is subsequently converted to cysteine, and cystine, which has an action on the central nervous system. However, there are few data about the possible application of N-Ac in the ethanol addiction. Behavioral sensitization is the gradual increase of the psychostimulant effects induced by repeated administration of drugs of abuse, including ethanol, and its development has been linked to important neuroadaptations in addiction. These neuroadaptations occur in neural circuits that mediate the reinforcing properties of these drugs and may involve several proteins. The ΔFosB protein accumulates in neurons after repeated activation and mediates long lasting changes in response to drugs of abuse. These changes are manifested mainly in the nucleus accumbens (Acb) and prefrontal cortex (PFC) neurons. The aim of the study was to evaluate the effects of N-Ac treatment in the development of ethanol behavioral sensitization and in alterations in the ΔFosB protein in mice. Swiss male mice were exposed to a standardized behavioral sensitization protocol to the experimental conditions of the laboratory and treated with N-Ac. At the end of behavioral sensitization procedure, animals were euthanized and their brains removed for ΔFosB quantification by Western blotting. Two experiments of behavioral sensitization were performed to the standardization of the protocol. The first, although effective in demonstrating the development of behavioral sensitization, was not effective in allowing the evaluation of the expression of the behavioral sensitization. The age of the animals and the conditions of luminosity and color of locomotion apparatus were changed and a new...

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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OBJETIVO: Apresentar a experiência de uma instituição brasileira no ensino da Reumatologia na graduação médica, cujo projeto pedagógico é estruturado em metodologias ativas de aprendizado. MÉTODOS: Realizou-se um estudo descritivo, com abordagem qualitativa dos conteúdos referentes à Reumatologia no curso de Medicina do Centro Universitário do Estado do Pará (Cesupa). RESULTADOS: O sistema musculoesquelético é abordado no segundo e sétimo semestres, nos módulos referentes ao sistema locomotor e Clínica Médica II, respectivamente, sendo que cada etapa e cada atividade apresentam objetivos específicos mínimos. Além do conteúdo teórico, no sétimo semestre, os alunos realizam atendimentos no ambulatório de Reumatologia, quando existe maior ênfase na elaboração correta de anamnese e exame físico. No internato, os alunos retornam ao ambulatório de Reumatologia e, neste momento, as habilidades de diagnóstico, de investigação e de terapêutica são as mais exigidas. CONCLUSÃO: Ainda há muito para evoluir em busca de um modelo ideal para o ensino da Reumatologia, porém, cumprindo as principais recomendações disponíveis para a boa prática do ensino na graduação, podemos proporcionar ao futuro médico conhecimento, habilidade e experiências capazes de ajudá-lo na condução desses pacientes.

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Pharmacological treatments currently used in ethanol addiction are inefficient, requiring new drugs for this purpose. The pro-drug N-Acetylcysteine (N-Ac) has shown efficacy in the treatment of addiction to cocaine and nicotine in preclinical research and clinical pilot studies. When administered, N-Ac is subsequently converted to cysteine, and cystine, which has an action on the central nervous system. However, there are few data about the possible application of N-Ac in the ethanol addiction. Behavioral sensitization is the gradual increase of the psychostimulant effects induced by repeated administration of drugs of abuse, including ethanol, and its development has been linked to important neuroadaptations in addiction. These neuroadaptations occur in neural circuits that mediate the reinforcing properties of these drugs and may involve several proteins. The ΔFosB protein accumulates in neurons after repeated activation and mediates long lasting changes in response to drugs of abuse. These changes are manifested mainly in the nucleus accumbens (Acb) and prefrontal cortex (PFC) neurons. The aim of the study was to evaluate the effects of N-Ac treatment in the development of ethanol behavioral sensitization and in alterations in the ΔFosB protein in mice. Swiss male mice were exposed to a standardized behavioral sensitization protocol to the experimental conditions of the laboratory and treated with N-Ac. At the end of behavioral sensitization procedure, animals were euthanized and their brains removed for ΔFosB quantification by Western blotting. Two experiments of behavioral sensitization were performed to the standardization of the protocol. The first, although effective in demonstrating the development of behavioral sensitization, was not effective in allowing the evaluation of the expression of the behavioral sensitization. The age of the animals and the conditions of luminosity and color of locomotion apparatus were changed and a new...

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Osteosarcoma (OS) is the most common primary malignant bone tumor, usually developing in children and adolescents, and is highly invasive and metastatic, potentially developing chemoresistance. Thus, novel effective treatment regimens are urgently needed. This study was the first to investigate the anticancer effects of dehydroxymethylepoxyquinomicin (DHMEQ), a highly specific nuclear factor-kappa B (NF-kappa B) inhibitor, on the OS cell lines HOS and MG-63. We demonstrate that NF-kappa B blockade by DHMEQ inhibits proliferation, decreases the mitotic index, and triggers apoptosis of OS cells. We examined the effects of combination treatment with DHMEQ and cisplatin, doxorubicin, or methotrexate, drugs commonly used in OS treatment. Using the median effect method of Chou and Talalay, we evaluated the combination indices for simultaneous and sequential treatment schedules. In all cases, combination with a chemotherapeutic drug produced a synergistic effect, even at low single-agent cytotoxic levels. When cells were treated with DHMEQ and cisplatin, a more synergistic effect was obtained using simultaneous treatment. For the doxorubicin and methotrexate combination, a more synergistic effect was achieved with sequential treatment using DHMEQ before chemotherapy. These synergistic effects were accompanied by enhancement of chemoinduced apoptosis. Interestingly, the highest apoptotic effect was reached with sequential exposure in both cell lines, independent of the chemotherapeutic agent used. Likewise, DHMEQ decreased cell invasion and migration, crucial steps for tumor progression. Our data suggest that combining DHMEQ with chemotherapeutic drugs might be useful for planning new therapeutic strategies for OS treatment, mainly in resistant and metastatic cases. Anti-Cancer Drugs 23:638-650 (C) 2012 Wolters Kluwer Health broken vertical bar Lippincott Williams & Wilkins.

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Cohabitation for 14 days with Ehrlich tumor-bearing mice was shown to increase locomotor activity, to decrease hypothalamic noradrenaline (NA) levels, to increase NA turnover and to decrease innate immune responses and decrease the animals' resistance to tumor growth. Cage mates of a B16F10 melanoma-bearer mice were also reported to show neuroimmune changes. Chemosignals released by Ehrlich tumor-bearing mice have been reported to be relevant for the neutrophil activity changes induced by cohabitation. The present experiment was designed to further analyze the effects of odor cues on neuroimmune changes induced by cohabitation with a sick cage mate. Specifically, the relevance of chemosignals released by an Ehrlich tumor-bearing mouse was assessed on the following: behavior (open-field and plus maze); hypothalamic NA levels and turnover; adrenaline (A) and NA plasmatic levels; and host resistance induced by tumor growth. To comply with such objectives, devices specifically constructed to analyze the influence of chemosignals released from tumor-bearing mice were employed. The results show that deprivation of odor cues released by Ehrlich tumor-bearing mice reversed the behavioral, neurochemical and immune changes induced by cohabitation. Mice use scents for intraspecies communication in many social contexts. Tumors produce volatile organic compounds released into the atmosphere through breath, sweat, and urine. Our results strongly suggest that volatile compounds released by Ehrlich tumor-injected mice are perceived by their conspecifics, inducing the neuroimmune changes reported for cohabitation with a sick companion. (C) 2011 Elsevier Inc. All rights reserved.

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Objective To determine whether activation of transient receptor potential vanilloid 4 (TRPV-4) induces inflammation in the rat temporomandibular joint (TMJ), and to assess the effects of TRPV-4 agonists and proinflammatory mediators, such as a protease-activated receptor 2 (PAR-2) agonist, on TRPV-4 responses. Methods Four hours after intraarticular injection of carrageenan into the rat joints, expression of TRPV-4 and PAR-2 in trigeminal ganglion (TG) neurons and in the TMJs were evaluated by real-time reverse transcriptionpolymerase chain reaction and immunofluorescence, followed by confocal microscopy. The functionality of TRPV-4 and its sensitization by a PAR-2activating peptide (PAR-2AP) were analyzed by measuring the intracellular Ca2+ concentration in TMJ fibroblast-like synovial cells or TG neurons. Plasma extravasation, myeloperoxidase activity, and the head-withdrawal threshold (index of mechanical allodynia) were evaluated after intraarticular injection of selective TRPV-4 agonists, either injected alone or coinjected with PAR-2AP. Results In the rat TMJs, TRPV-4 and PAR-2 expression levels were up-regulated after the induction of inflammation. Two TRPV-4 agonists specifically activated calcium influx in TMJ fibroblast-like synovial cells or TG neurons. In vivo, the agonists triggered dose-dependent increases in plasma extravasation, myeloperoxidase activity, and mechanical allodynia. In synovial cells or TG neurons, pretreatment with PAR-2AP potentiated a TRPV-4 agonistinduced increase in [Ca2+]i. In addition, TRPV-4 agonistinduced inflammation was potentiated by PAR-2AP in vivo. Conclusion In this rat model, TRPV-4 is expressed and functional in TG neurons and synovial cells, and activation of TRPV-4 in vivo causes inflammation in the TMJ. Proinflammatory mediators, such as PAR-2 agonists, sensitize the activity of TRPV-4. These results identify TRPV-4 as an important signal of inflammation in the joint.

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This study investigated whether perinatal exposure to picrotoxin, a GABA(A) antagonist, modifies the effect of muscimol, a GABA(A) agonist, on the sexual behavior of adult male rats. Two hours after birth and then once daily during the next 9 days of lactation, dams received picrotoxin (0.75 mg/kg subcutaneously) or saline (1 ml/kg subcutaneously). The adult male offspring from the picrotoxin and saline groups received saline (1 ml/kg intraperitoneally) or muscimol (1 mg/kg intraperitoneally), and 15 min later, their sexual behavior was assessed. Muscimol treatment in the saline-exposed group increased the mount and intromission latencies. However, these effects were absent in the picrotoxin-exposed groups. The latencies to first ejaculation, postejaculatory mount, and intromission were decreased in both picrotoxin-exposed groups relative to the saline-exposed groups. The picrotoxin + muscimol-treated rats required more intromissions to ejaculate and the picrotoxin-exposed groups made more ejaculations than the saline-exposed groups. Thus, muscimol treatment did not increase the mount and intromission latencies following picrotoxin exposure, but increased the ejaculation frequency, which did not differ between the picrotoxin + muscimol and the picrotoxin + saline groups. These data indicate that perinatal picrotoxin treatment interfered with GABA(A) receptor development Behavioural Pharmacology 23:703-709 (c) 2012 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

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Objective This study investigated environmental endotoxin exposure during early life, sensitization to aeroallergens, the production of cytokines by LPS-stimulated leukocytes, and the development of a wheezing phenotype in a prospective cohort of infants with high risk of developing allergic diseases. Materials and Methods Eighty-four infants were followed from birth until 30 months of age. We assessed endotoxin concentration in house dust of their homes during the first 6 months of life. At age 30 months they were clinically evaluated to determine the development of wheezing and other clinical events, were skin prick tested, and had blood samples collected for the evaluation of cytokine release by LPS-stimulated peripheral blood mononuclear cells (PBMC). Results The level of endotoxin exposure during early life was not associated with development of a wheezing phenotype. On the other hand a higher incidence of respiratory infections occurred among recurrent wheezing (RW) infants. PBMC from RW children exposed to higher levels of environmental endotoxin (above 50?EU/mg) released less Interleukin (IL)-12p70 and IFN-? compared to the non-RW group. TNF-a, IL-10, IL-4, IL-5, and IL17 production by LPS-stimulated PBMC from RW and non-RW children was equivalent in both groups of environmental endotoxin exposure. Conclusion In this prospective cohort of infants with high risk of developing allergic diseases we observed that RW and non-RW children were exposed to similar levels of endotoxin early in life. LPS-stimulated PBMC from RW infants exposed to higher levels of endotoxin released significantly less IL-12 and IFN-? compared to non-RW infants. Pediatr Pulmonol. 2012. 47:10541060. (C) 2012 Wiley Periodicals, Inc.

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Since there was no Portuguese questionnaire to evaluate cutaneous allodynia, which has been pointed out as a risk factor of migraine, we aimed to perform the cross-cultural adaptation of the 12 item Allodynia Symptom Checklist for the Brazilian population and to test its measurement properties. It consisted in six stages: translation, synthesis, back translation, revision by a specialist committee, pretest and submission the documents to the committee. In the pretest stage, the questionnaire was applied to 30 migraineurs of both sexes, who had some difficulty in understanding it. Thus, a second version was applied to 30 additional subjects, with no difficulties being reported. The mean filling out time was 3'36", and the internal consistency was 0.76. To test reproducibility, 15 other subjects filled out the questionnaire at two different times, it was classified as moderate (weighted kappa=0.58). We made available to Brazilian population an easy, quick and reliable questionnaire.

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Subterranean organisms are excellent models for chronobiological studies, yet relatively few taxa have been investigated with this focus. Former results were interpreted as a pattern of regression of circadian locomotor activity rhythms in troglobitic (exclusively subterranean) species. In this paper we report results of experiments with cave fishes showing variable degrees of troglomorphism (reduction of eyes, melanic pigmentation and other specializations related to the hypogean life) submitted to light-dark cycles, preceded and followed by several days in constant darkness. Samples from seven species have been monitored in our laboratory for the detection of significant circadian rhythms in locomotor activity: S. typhlops, an extremely troglomophic species, presented the lowest number of significant components in the circadian range (only one individual out of eight in DD1 and three other fish in LD), all weak (low values of spectral power). Higher incidence of circadian components was observed for P. kronei - only one among six studied catfish without significant circadian rhythms under DD1 and DD2; spectral powers were generally high. Intermediate situations were observed for the remaining species, however all of them presented relatively strong significant rhythms under LD. Residual oscillations (circadian rhythms in DD2) were detected in at least part of the studied individuals of all species but S. typhlops, without a correlation with spectral powers of LD rhythms, i.e., individuals exhibiting residual oscillations were not necessarily those with the strongest LD rhythms. In conclusion, the accumulated evidence for troglobitic fishes strongly supports the hypothesis of external, environmental selection for circadian locomotor rhythms.

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We studied locomotor activity rhythms of C57/Bl6 mice under a chronic jet lag (CJL) protocol (ChrA(6/2)), which consisted of 6-hour phase advances of the light-dark schedule (LD) every 2 days. Through periodogram analysis, we found 2 components of the activity rhythm: a short-period component (21.01 +/- 0.04 h) that was entrained by the LD schedule and a long-period component (24.68 +/- 0.26 h). We developed a mathematical model comprising 2 coupled circadian oscillators that was tested experimentally with different CJL schedules. Our simulations suggested that under CJL, the system behaves as if it were under a zeitgeber with a period determined by (24 -[phase shift size/days between shifts]). Desynchronization within the system arises according to whether this effective zeitgeber is inside or outside the range of entrainment of the oscillators. In this sense, ChrA(6/2) is interpreted as a (24 - 6/2 = 21 h) zeitgeber, and simulations predicted the behavior of mice under other CJL schedules with an effective 21-hour zeitgeber. Animals studied under an asymmetric T = 21 h zeitgeber (carried out by a 3-hour shortening of every dark phase) showed 2 activity components as observed under ChrA(6/2): an entrained short-period (21.01 +/- 0.03 h) and a long-period component (23.93 +/- 0.31 h). Internal desynchronization was lost when mice were subjected to 9-hour advances every 3 days, a possibility also contemplated by the simulations. Simulations also predicted that desynchronization should be less prevalent under delaying than under advancing CJL. Indeed, most mice subjected to 6-hour delay shifts every 2 days (an effective 27-hour zeitgeber) displayed a single entrained activity component (26.92 +/- 0.11 h). Our results demonstrate that the disruption provoked by CJL schedules is not dependent on the phase-shift magnitude or the frequency of the shifts separately but on the combination of both, through its ratio and additionally on their absolute values. In this study, we present a novel model of forced desynchronization in mice under a specific CJL schedule; in addition, our model provides theoretical tools for the evaluation of circadian disruption under CJL conditions that are currently used in circadian research.

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We present four cases of headache with variable intensity, located in close proximity to a craniotomy incision which was performed for non-traumatic reasons. Since manual palpation of the scar often triggers pain, and infiltration with local anesthetics reduce or abolish the pain in some patients, we suggest that neuromas or nerve entrapment in the scars, as a result of the surgery, are responsible for headaches. Although local infiltrations or nerve blocks are often used for diagnostic reasons, herein we consider that they are also of therapeutic value. We review the current known pathophysiology of post-craniotomy headaches and present a hypothesis suggesting a greater recognition of the potential contribution of neuroma formation in areas of scars tissue to contribute to this kind of headache.

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We evaluated the effects of aerobic exercise (AE) on airway inflammation, exhaled nitric oxide levels (ENO), airway remodeling, and the expression of Thl, Th2 and regulatory cytokines in a guinea pig asthma model. Animals were divided into 4 groups: non-trained and non-sensitized (C), non-sensitized and AE (AE), ovalbumin-sensitized and non-trained (OVA), and OVA-sensitized and AE (OVA + AE). OVA inhalation was performed for 8 weeks, and AE was conducted for 6 weeks beginning in the 3rd week of OVA sensitization. Compared to the other groups, the OVA + AE group had a reduced density of eosinophils and lymphocytes, reduced expression of interleukin (IL)-4 and IL-13 and an increase in epithelium thickness (p < 0.05). AE did not modify airway remodeling or ENO in the sensitized groups (p > 0.05). Neither OVA nor AE resulted in differences in the expression of IL-2, IFN-gamma, IL-10 or IL1-ra. Our results show that AE reduces the expression of Th2 cytokines and allergic airway inflammation and induces epithelium remodeling in sensitized guinea pigs. (c) 2012 Elsevier B.V. All rights reserved.