137 resultados para central-nervous-system
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Gender may produce different characteristics in the manifestation of systemic lupus erythematosus (SLE). The present study investigated the influence of gender on clinical, laboratory, autoantibodies and histopathological classes of lupus nephritis (LN). As much as 81 patients diagnosed with SLE (ACR criteria) and active nephritis, who underwent renal biopsy between 1999 and 2004, and who had frozen serum samples and clinical data available from the time of biopsy, were selected for this study. The presence of anti-P and antichromatin antibodies was measured using ELISA, and anti-dsDNA was measured using indirect immunofluorescence. All of the renal biopsies were reviewed in a blinded manner by the same expert renal pathologist. The charts were extensively reviewed for demographic and renal features obtained at the time of the biopsy. Of the 81 patients (13.6%), 11 were male SLE patients. Both male and female lupus patients were of similar age and race, and had similar durations of lupus and renal disease. The female patients had more cutaneous (95.7 vs. 45.5%, P = 0.0001) and haematological (52.9 vs. 18.2%, P = 0.04) involvements than the male SLE patients. In addition, the articular data, central nervous system analyses, serositis findings and SLEDAI scores were similar in both experimental groups. Positivity for anti-dsDNA, anti-ribosomal P and antichromatin did not differ between the two groups, and both groups showed similarly low C3 or C4 serum levels. Our analysis indicated that no histopathological class of LN was predominant in both males and females. Interestingly, the serum creatinine levels were higher in the male SLE patients compared to the female SLE group (3.16 +/- A 2.49 vs. 1.99 +/- A 1.54 mg/dL, P = 0.03), with an increased frequency of high creatinine (81.8 vs. 47.1%, P = 0.04) as well as renal activity index (7.6 +/- A 3.5 vs. 4.8 +/- A 3.5, P = 0.02). In addition, whilst the mean levels of proteinuria, cylindruria and serum albumin were markedly altered, they were comparable between both lupus men and women. Moreover, the frequencies of dialysis, renal transplantation and death were similar between the two groups. These data suggest that male patients had a more severe LN compared to women diagnosed with this renal abnormality.
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Introduction. Chagas` disease is endemic in South America. Objective. This research reviewed the experience with cardiac transplantation in Chagas` disease, emphasizing reactivation, immunosuppression, and mortality. Methods. Over 25 years from March 1985 to March 2010, 107/409 (26.2%) patients with Chagas` disease underwent heart transplantation, patients including 74 (71.1%) men and 72 (67.2%), in functional class IV with 33 (30.8%) on vasopressors and 17 (10.7%) on mechanical circulatory support. Results. The diagnosis of disease reactivation was performed by identifying the parasite in the myocardium (n = 23; 71.8%) in the subcutaneous tissue (n = 8; 25.0%), in blood (n = 11; 34.3%), or in central nervous tissue (n = 1; 3.1%). Hospital mortality was 17.7% (n = 19) due to infection (n = 6; 31.5%), graft dysfunction (n = 6; 31.5%), rejection (n 4; 21.1%), or sudden death (n = 2; 10.5%). Late mortality was 27 (25.2%) cases, which were distributed as: rejection (n = 6; 22.2%), infection (n = 6; 22.2%), (n = lymphoma 4; 14.8%), sarcoma (n = 2; 7.4%), for constrictive pericarditis (n = 2; 7.4%) reactivation of Chagas` disease in the central nervous system (n = 1; 7.1%). Conclusions. Transplantation in Chagas` disease has peculiar problems that differ from other etiologies due to the possibility of disease reactivation and the increased possibility of emergence of cancers. However, transplantation is the only treatment able to modify the natural progression of the disease in its terminal phase. Early diagnosis and rapid introduction of benzonidazole reverses the histological patterns. Immunosuppression, especially steroids, predisposes to the development of cancer and disease reactivation.
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Background and purpose: Tinnitus is a frequent disorder which is very difficult to treat and there is compelling evidence that tinnitus is associated with functional alterations in the central nervous system. Targeted modulation of tinnitus-related cortical activity has been proposed as a promising new treatment approach. We aimed to investigate both immediate and long-term effects of low frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS) in patients with tinnitus and normal hearing. Methods: Using a parallel design, 20 patients were randomized to receive either active or placebo stimulation over the left temporoparietal cortex for five consecutive days. Treatment results were assessed by using the Tinnitus Handicap Inventory. Ethyl cysteinate dimmer-single photon emission computed tomography (SPECT) imaging was performed before and 14 days after rTMS. Results: After active rTMS there was significant improvement of the tinnitus score as compared to sham rTMS for up to 6 months after stimulation. SPECT measurements demonstrated a reduction of metabolic activity in the inferior left temporal lobe after active rTMS. Conclusion: These results support the potential of rTMS as a new therapeutic tool for the treatment of chronic tinnitus, by demonstrating a significant reduction of tinnitus complaints over a period of at least 6 months and significant reduction of neural activity in the inferior temporal cortex, despite the stimulation applied on the superior temporal cortex.
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Vitamin D (VD), is a steroid hormone with multiple functions in the central nervous system (CNS), producing numerous physiological effects mediated by its receptor (VDR). Clinical and experimental studies have shown a link between VD dysfunction and epilepsy. Along these lines, the purpose of our work was to analyze the relative expression of VDR mRNA in the hippocampal formation of rats during the three periods of pilocarpine-induced epilepsy. Male Wistar rats were divided into five groups: (1) control group; rats that received saline 0.9%, i.p. and were killed 7 days after its administration (CTRL, n = 8), (2) SE group; rats that received pilocarpine and were killed 4 h after SE (SE, n = 8), (3) Silent group-7 days; rats that received pilocarpine and were killed 7 days after SE (SIL 7d, n = 8), (4) Silent group-14 days; rats that received pilocarpine and were killed 14 days after SE (SIL 14d, n = 8), (5) Chronic group; rats that received pilocarpine and were killed 60 days after the first spontaneous seizure, (chronic, n = 8). The relative expression of VDR mRNA was determined by real-time PCR. Our results showed an increase of the relative expression of VDR mRNA in the SIL 7 days, SIL 14 days and Chronic groups, respectively (0.060 +/- 0.024; 0.052 +/- 0.035; 0.085 +/- 0.055) when compared with the CTRL and SE groups (0.019 +/- 0.017; 0.019 +/- 0.025). These data suggest the VDR as a possible candidate participating in the epileptogenesis process of the pilocarpine model of epilepsy. (C) 2008 Elsevier Inc. All rights reserved.
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Medulloblastomas are the most common malignant tumors of the central nervous system in childhood. The incidence is about 19-20% between children younger than 16 years old with peak incidence between 4 and 7 years. Despite its sensibility to no specific therapeutic means like chemotherapy and radiotherapy, the treatment is very aggressive and frequently results in regression, growth deficit, and endocrine dysfunction. From this point of view, new treatment approaches are needed such as molecular targeted therapies. Studies in glioblastoma demonstrated that ASPM gene was overexpressed when compared to normal brain and ASPM inhibition by siRNA-mediated inhibits tumor cell proliferation and neural stem cell proliferation, supporting ASPM gene as a potential molecular target in glioblastoma. The aim of this work was to evaluate ASPM expression in medulloblastoma fragment samples, and to compare the results with the patient clinical features. Analysis of gene expression was performed by quantitative PCR real time using SYBR Green system in tumor samples from 37 children. The t test was used to analyze the gene expression, and Mann-Whitney test was performed to analyze the relationship between gene expressions and clinical characteristics. Kaplan-Meier test evaluated curve survival. All samples overexpressed ASPM gene more than 40-fold. However, we did not find any association between the overexpressed samples and the clinical parameters. ASPM overexpression may modify the ability of stem cells to differentiate during the development of the central nervous system, contributing to the development of medulloblastoma, a tumor of embryonic origin from cerebellar progenitor cells.
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It is known that physical activity triggers changes in the central nervous system Adult rats, trained on treadmills for 4 weeks, and a group of sedentary rats was submitted to contuse moderate spinal cord injury A group of sedentary rats was submitted to a sham operation The trained group continued running on treadmill after lesion for 4 weeks Motor behavior evaluated by BBB score was smaller in the sedentary group compared to the trained rats by 7 days after lesion Computerized activity monitor showed clear-cut differences in spontaneous motor parameters in trained rats only before lesion After surgery, sedentary rats showed changes in motor parameters but not in later periods of analysis Animals were euthanized by 28 days after surgery, and their spinal cords were processed for Nissl staining and immunohistochemistry The number of the remaining neurons and the lesion areal and lesion volume fractions were obtained by stereological method The number of the remaining neurons did not change after training Lesion volume and lesion areal fraction per section were smaller in the trained group Lesion index was more pronounced in the sedentary group Microdensitometric image analysis demonstrated a microglial reaction, astroglial activation, and glial FGF-2 production more pronounced in the spinal cord of sedentary animals GAP-43 was higher in caudal levels of contusion in the sedentary group In conclusion, treadmill running may favor a better functional recovery in the acute period after spinal cord lesion and wound repair processes leading to neuroprotection (C) 2010 Elsevier B V All rights reserved
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This paper analyzes the astroglial and neuronal responses in subtelencephalic structures, following a bilateral ablation of the telencephalon in the Columba livia pigeons. Control birds received a sham operation. Four months later the birds were sacrificed and their brains processed for glial fribillary acid protein (GFAP) and neurofilament immunohistochemistry, markers for astrocytes and neurons, respectively. Computer-assisted image analysis was employed for quantification of the immunoreactive labeling in the nucleus rotundus (N.Rt) and the optic tectum (OT) of the birds. An increased number of GFAP immunoreactive astrocytes were found in several subregions of the N.Rt (p .001), as well as in layers 1, 2cd, 3, and 6 of the OT (p .001) of the lesioned animals. Neurofilament immunoreactivity decreased massively in the entire N.Rt of the lesioned birds; however, remaining neurons with healthy aspect showing large cytoplasm and ramified branches were detected mainly in the periphery of the nucleus. In view of the recently described paracrine neurotrophic properties of the activated astrocytes, the data of the present study may suggest a long-lasting neuroglial interaction in regions of the lesioned bird brain far from injury. Such events may trigger neuronal plasticity in remaining brain structures that may lead spontaneous behavior recovery as the one promoted here even after a massive injury.
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We have observed in previous studies that 6-hydroxydopamine (6-OHDA)-induced lesions in the nigrostriatal dopamine (DA) system promote increases of the astroglial basic fibroblast growth factor (FGF-2, bFGF) synthesis in the ascending DA pathways, event that could be modified by adrenosteroid hormones. Here, we first evaluated the changes of microglial reactivity in relation to the FGF-2-mediated trophic responses in the lesioned nigrostriatal DA system. 6-OHDA was injected into the left side of the rat substantia nigra. The OX42 immunohistochemistry combined with stereology showed the time course of the microglial activation. The OX42 immunoreactivity (IR) was already increased in the pars compacta of the substantia nigra (SNc) and ventral tegmental area (VTA) 2 h after the 6-OHDA injection, peaked on day 7, and remained increased on the 14th day time-interval. In the neostriatum, OX42 immunoreactive (ir) microglial profiles increased at 24 h, peaked at 72 h, was still increased at 7 days but not 14 days after the 6-OHDA injection. Two-colour immunofluorescence analysis of the tyrosine hydroxylase (TH) and OX42 IRs revealed the presence of small patches of TH IR within the activated microglia. A decreased FGF-2 IR was seen in the cytoplasm of DA neurons of the SNc and VTA as soon as 2 h after 6-OHDA injection. The majority of the DA FGF-2 ir cells of these regions had disappeared 72 h after neurotoxin. The astroglial FGF-2 IR increased in the SNc and VTA, which peaked on day 7. Two-colour immunofluorescence and immunoperoxidase analyses of the FGF-2 and OX42 IRs revealed no FGF-2 IR within the reactive or resting microglia. Second, we have evaluated in a series of biochemical experiments whether adrenocortical manipulation can interfere with the nigral lesion and the state of local astroglial reaction, looking at the TH and GFAP levels respectively. Rats were adrenalectomized (ADX) and received a nigral 6-OHDA stereotaxical injection 2 days later and sacrificed up to 3 weeks after the DA lesion. Western blot analysis showed time-dependent decrease and elevation of TH and GFAP levels, respectively, in the lesioned versus contralateral midbrain sides, events potentiated by ADX and worsened by corticosterone replacement. ADX decreased the levels of FGF-2 protein (23 kDa isoform) in the lesioned side of the ventral midbrain compared contralaterally. The results indicate that reactive astroglia, but not reactive microglia, showed an increased FGF-2 IR in the process of DA cell degeneration induced by 6-OHDA. However, interactions between these glial cells may be relevant to the mechanisms which trigger the increased astroglial FGF-2 synthesis and thus may be related to the trophic state of DA neurons and the repair processes following DA lesion. The findings also gave further evidence that adrenocortical hormones may regulate astroglial-mediated trophic mechanisms and wound repair events in the lesioned DA system that may be relevant to the progression of Parkinson`s disease.
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Glutamatergic transmission through metabotropic and ionotropic receptors, including kainate receptors, plays an important role in the nucleus of the solitary tract (NTS) functions. Glutamate system may interact with several other neurotransmitter systems which might also be influenced by steroid hormones. In the present study we analyzed the ability of systemic kainate to stimulate rat NTS neurons, which was evaluated by c-Fos as a marker of neuronal activation, and also to change the levels of NTS neurotransmitters such as GABA, NPY, CGRP, GAL, NT and NO by means of quantitative immunohistichemistry combined with image analysis. The analysis was also performed in adrenalectomized and kainate stimulated rats in order to evaluate a possible role of adrenal hormones on NTS neurotransmission. Male Wistar rats (3 month-old) were used in the present study. A group of 15 rats was submitted either to bilateral adrenalectomy or sham operation. Forty-eight hours after the surgeries, adrenalectomized rats received a single intraperitoneal injection of kainate (12 mg/kg) and the sham-operated rats were injected either with saline or kainate and sacrificed 8 hours later. The same experimental design was applied in a group of rats in order to register the arterial blood pressure. Systemic kainate decreased the basal values of mean arterial blood pressure (35%) and heart rate (22%) of sham-operated rats, reduction that were maintained in adrenalectomized rats. Kainate triggered a marked elevation of c-Fos positive neurons in the NTS which was 54% counteracted by adrenalectomy. The kainate activated NTS showed changes in the immunoreactive levels of GABA (143% of elevation) and NPY (36% of decrease), which were not modified by previous ablation of adrenal glands. Modulation in the levels of CGRP, GAL and NT immunoreactivities were only observed after kainate in the adrenalectomized rats. Treatments did not alter NOS labeling. It is possible that modulatory function among neurotransmitter systems in the NTS might be influenced by steroid hormones and the implications for central regulation of blood pressure or other visceral regulatory mechanisms control should be further investigated.
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Objetive: To evaluate the effects of conjugated equine estrogens (CEE) on the pilocarpine-induced epilepsy in rats. Study design: 40 female rats were divided into: GPC (positive control) presented ""status epilepticus"" (SE) induced by pilocarpine; GOC(ovariectomized control) only castrated; GNC (negative control) received only saline solution; GPE received pilocarpine, presented SE, castrated and received 50 mu g/kg CEE treatment; GPV received pilocarpine, castrated and received propylene glycol (vehicle). The animals were monitored by a video system. At the end of observation, the brains removed for later histologic analysis using Neo-Timm and Nissl methods. Results: The GPE presented a reduction in number of seizures compared to GPV. The Neo-Timm analysis showed that GPV had greater sprouting of mossy fibers, with a denser band in the area of the dentate gyrus hilum compared to GPE. On Nissl staining, GPE showed evident neuronal loss in the CA3 area. GPV presented loss in CA1 and dentate gyrus. Conclusion: Estrogen may have a protecting effect on the central nervous system. (C) 2008 Elsevier Ireland Ltd. All rights reserved.
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Study design: A prospective, non-randomized clinical series trial. Objective: To evaluate the effect of autogenous undifferentiated stem cell infusion for the treatment of patients with chronic spinal cord injury (SCI) on somatosensory evoked potentials (SSEPs). Setting: A public tertiary hospital in Sao Paulo, Brazil. Methods: Thirty-nine consecutive patients with diagnosed complete cervical and thoracic SCI for at least 2 years and with no cortical response in the SSEP study of the lower limbs were included in the trial. The trial patients underwent peripheral blood stem cell mobilization and collection. The stem cell concentrate was cryopreserved and reinfused through arteriography into the donor patient. The patients were followed up for 2.5 years and submitted to SSEP studies to evaluate the improvement in SSEPs after undifferentiated cell infusion. Results: Twenty-six (66.7%) patients showed recovery of somatosensory evoked response to peripheral stimuli after 2.5 years of follow-up. Conclusion: The 2.5-year trial protocol proved to be safe and improved SSEPs in patients with complete SCI. Sponsorship: None. Spinal Cord (2009) 47, 733-738; doi: 10.1038/sc.2009.24; published online 31 March 2009
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Purpose of review To explore recent findings bridging childhood development and common late-life mental disorders in the elderly. Recent findings We addressed aging as a part of the developmental process in central nervous system, typical and atypical neurodevelopment focusing on genetic and environmental risk factors and their interplay and links between psychopathology from childhood to the elderly, unifying theoretical perspectives and preventive intervention strategies. Summary Current findings suggest that childhood development is strictly connected to psychiatric phenotypes across the lifespan. Although we are far from a comprehensive understanding of mental health trajectories, some initial findings document both heterotypic and homotypic continuities from childhood to adulthood and from adulthood to the elderly. Our review also highlights the urgent need for investigations on preventive interventions in individuals at risk for mental disorders.
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Centella asiatica (L.) Urb an is distributed widely in South America and Asia and is known as a therapeutic agent in folk medicine, capable of improving memory and treating several neurological disorders. Asiaticoside is one of the compounds found in C asiatica leaves that is suggested to be responsible for its pharmacological potential. Phospholipase A(2) (PLA(2)) is a group of enzymes that has abnormal activity in the central nervous system in some neuropsychiatric diseases. In this work, the asiaticoside present in C asiatica water extract was quantified by HPLC analysis. We also evaluated the activity of subtypes of PLA(2) in cerebellar samples from rats after C asiatica water extract treatment using a radioenzymatic assay. Asiaticoside was the major compound (84%) found in Centella water extract. We found a dose-dependent inhibitory effect of C asiatica water extract on the activity of Ca(2+)-independent PLA(2) (iPLA(2)) and cytosolic PLA(2) (cPLA(2)). The inhibition of these enzymes in the brain suggests that C asiatica may be useful to treat conditions associated with increased PLA(2) activity in the brain, such as epilepsy, stroke, multiple sclerosis and other neuropsychiatric disorders. (C) 2008 Elsevier GmbH. All rights reserved.
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Several epidemiological studies have linked particulate matter exposure to numerous adverse health effects on the respiratory, cardiovascular, and reproductive systems (Braga et al., 1999; Zanobetti et al., 2000; Anderson et al., 2001; Farhat et al., 2005). More recently, ambient levels of black carbon were associated to impaired cognitive function in children (Suglia et al., 2008), suggesting that the central nervous system (CNS) may be a target of air pollutants. The present study was conducted to (a) determine whether chronic residual oil fly ash (ROFA) exposure promotes behavioral changes and lipid peroxidation in rat brain areas, and (b) determine whether N-acetylcysteine (NAC), a general antioxidant, prevents these effects. Forty-five-day-old male Wistar rats were exposed or not to ROFA by intranasal instillation and were treated or not with NAC (150 mg/kg) ip for 30 days. One day later, rats were submitted to the open field test to evaluate the motor/exploratory activities and emotionality followed by decapitation. Striatum and cerebellum were dissected to determine lipid peroxidation by the accumulation of thiobarbituric acid-reactive substances (TBARS). ROFA instillation induced an increase in lipid peroxidation level in striatum (p = .033) and cerebellum (p = .030), as compared with the control group. NAC treatment blocked these changes. ROFA promoted a decrease in the frequency of peripheral walking (p = .006) and a decrease in exploration (p = .001), which were not blocked by N-acetylcysteine. The present study provides evidence that toxic particles, administered by the respiratory route, induce oxidative stress in structures of the central nervous system, as well as behavioral alterations. The administration of NAC reduces lipid peroxidation at the striatum and cerebellum levels, but does not influence behavioral disturbances.
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Epidemiological studies have demonstrated the adverse effects of particulate matter (PM) inhalation on the respiratory and cardiovascular systems. It has been reported that air pollution may affect the central nervous system and decrease cognitive function. In rats, residual oil fly ash (ROFA) instillation causes decreased motor activity and increased lipid peroxidation in the striatum and the cerebellum. Our objective was to determine whether chronic instillation of particles induces changes in learning and memory in rats and whether oxidants in the hippocampus may contribute to these adverse effects. Forty-five-day-old male Wistar rats were exposed to ROFA by intranasal instillation and were treated with N-acetylcysteine (NAC) at 150 mg/kg i.p. for 30 days. Control groups were exposed to ROFA, NAC, or neither. On days 1, 8, and 30 of the protocol, rats were submitted to the open field test to evaluate habituation. After the last open field session, the rats were killed by decapitation. The hippocampus was used to determine lipid peroxidation (LP) by the thiobarbituric acid-reactive substances test. ROFA instillation induced an increase in LP in the hippocampus compared to all treatment groups (p = .012). NAC treatment blocked these changes. All of the treatment groups presented a decrease in the frequency of peripheral walking (p = .001), rearing (p = .001), and exploration (p = .001) over time. Our study demonstrates that exposure to particles for 30 days and/or NAC treatment do not modify habituation to an open field, a simple form of learning and memory in rats, and that oxidative damage induced by ROFA does not modulate these processes.