33 research outputs found
Intrinsic up-regulation of 2-AG favors an area specific neuronal survival in different in vitro models of neuronal damage
BACKGROUND: The endocannabinoid 2-arachidonoyl glycerol (2-AG) acts as a retrograde messenger and modulates synaptic signaling e. g. in the hippocampus. 2-AG also exerts neuroprotective effects under pathological situations. To better understand the mechanism beyond physiological signaling we used Organotypic Entorhino-Hippocampal Slice Cultures (OHSC) and investigated the temporal regulation of 2-AG in different cell subsets during excitotoxic lesion and dendritic lesion of long range projections in the enthorhinal cortex (EC), dentate gyrus (DG) and the cornu ammonis region 1 (CA1).
RESULTS: 2-AG levels were elevated 24 h after excitotoxic lesion in CA1 and DG (but not EC) and 24 h after perforant pathway transection (PPT) in the DG only. After PPT diacylglycerol lipase alpha (DAGL) protein, the synthesizing enzyme of 2-AG was decreased when Dagl mRNA expression and 2-AG levels were enhanced. In contrast to DAGL, the 2-AG hydrolyzing enzyme monoacylglycerol lipase (MAGL) showed no alterations in total protein and mRNA expression after PPT in OHSC. MAGL immunoreaction underwent a redistribution after PPT and excitotoxic lesion since MAGL IR disappeared in astrocytes of lesioned OHSC. DAGL and MAGL immunoreactions were not detectable in microglia at all investigated time points. Thus, induction of the neuroprotective endocannabinoid 2-AG might be generally accomplished by down-regulation of MAGL in astrocytes after neuronal lesions.
CONCLUSION: Increase in 2-AG levels during secondary neuronal damage reflects a general neuroprotective mechanism since it occurred independently in both different lesion models. This intrinsic up-regulation of 2-AG is synergistically controlled by DAGL and MAGL in neurons and astrocytes and thus represents a protective system for neurons that is involved in dendritic reorganisation
Pediatric cancer and Li-Fraumeni/Li-Fraumeni-like syndromes : a review for the pediatrician
Introduction: cancer is the second leading cause of death in children between the ages of 0 and 14 years, corresponding to approximately 3% of all cases diagnosed in Brazil. A significant percentage (5-10%) of pediatric cancers are associated with hereditary cancer syndromes, including Li-Fraumeni/Li-Fraumeni-like syndromes (LFS/LFL), both of which are caused by TP53 germline mutations. Recent studies have shown that a specific TP53 mutation, known as p.R337H, is present in 1 in 300 newborns in Southern and Southeast Brazil. In addition, a significant percentage of children with LFS/LFL spectrum tumors in the region have a family history compatible with LFS/LFL. Objective: to review clinical relevant aspects of LFS/LFL by our multidisciplinary team with focus on pediatric cancer. ( continues) Methods: the NCBI (PubMed) and SciELO databases were consulted using the keywords Li-Fraumeni syndrome, Li-Fraumeni-like syndrome and pediatric cancer; and all manuscripts published between 1990 and 2014 using these keywords were retrieved and reviewed. Conclusion: although LFS/LFL is considered a rare disease, it appears to be substantially more common in certain geographic regions. Recognition of population- specific risks for the syndrome is important for adequate management of hereditary cancer patients and families. In Southern and Southeastern Brazil, LFS/ LFL should be considered in the differential diagnosis of children with cancer, especially if within the spectrum of the syndrome. Due to the complexities of these syndromes, a multidisciplinary approach should be sought for the counseling, diagnosis and management of patients and families affected by these disorders. Pediatricians and pediatric oncologists in areas with high prevalence of hereditary cancer syndromes have a central role in the recognition and proper referral of patients and families to genetic cancer risk evaluation and management programs.Câncer pediátrico e sÃndrome de Li-Fraumeni/Li-Fraumeni- like: uma revisão para o pediatra. Introdução: o câncer é a segunda principal causa de morte em crianças com idades entre 0 e 14 anos, correspondendo a cerca de 3% de todos os casos diagnosticados no Brasil. Um percentual significativo (5-10%) dos cânceres pediátricos são associados a sÃndromes hereditárias para câncer, incluindo Li-Fraumeni/Li-Fraumeni-like sÃndromes (LFS/LFL), causadas por mutações germinativas no gene TP53. Estudos recentes têm demonstrado que uma mutação especÃfica em TP53, conhecida como p.R337H, está presente em 1 em 300 recém-nascidos no Sul e Sudeste do Brasil. Além disso, um percentual significativo de crianças com tumores do espectro LFS/LFL na região têm uma história familiar compatÃvel com a sÃndrome. Objetivos: revisão dos aspectos clÃnicos relevantes da LFS/LFL por equipe multidisciplinar, com foco no câncer pediátrico Métodos: o NCBI (PubMed) e SciELO foram consultados, usando as palavras-chave sÃndrome de Li-Fraumeni,sÃndrome de Li-Fraumeni-like e câncer pediátrico. Todos os artigos publicados entre 1990 e 2014 usando essas palavras- chave foram recuperados e revisados. Conclusão: apesar de LFS/LFL ser considerada uma doença rara, ela parece ser mais frequente em certas regiões. Reconhecer os critérios e condutas para identificação de pacientes em risco para LFS/LFL é fundamental para o manejo adequado dos pacientes com câncer hereditários e suas famÃlias. Devido à complexidade dessas sÃndromes, a abordagem multidisciplinar deve ser realizada. Pediatras e oncologistas pediátricos em áreas com alta prevalência de sÃndromes hereditárias de câncer têm um papel central no reconhecimento e encaminhamento adequado dos pacientes e famÃlias para programas de avaliação do risco de câncer genético e de gestão
R-Flurbiprofen Reduces Neuropathic Pain in Rodents by Restoring Endogenous Cannabinoids
Background: R-flurbiprofen, one of the enantiomers of flurbiprofen racemate, is inactive with respect to cyclooxygenase inhibition, but shows analgesic properties without relevant toxicity. Its mode of action is still unclear. Methodology/Principal Findings: We show that R-flurbiprofen reduces glutamate release in the dorsal horn of the spinal cord evoked by sciatic nerve injury and thereby alleviates pain in sciatic nerve injury models of neuropathic pain in rats and mice. This is mediated by restoring the balance of endocannabinoids (eCB), which is disturbed following peripheral nerve injury in the DRGs, spinal cord and forebrain. The imbalance results from transcriptional adaptations of fatty acid amide hydrolase (FAAH) and NAPE-phospholipase D, i.e. the major enzymes involved in anandamide metabolism and synthesis, respectively. R-flurbiprofen inhibits FAAH activity and normalizes NAPE-PLD expression. As a consequence, R-Flurbiprofen improves endogenous cannabinoid mediated effects, indicated by the reduction of glutamate release, increased activity of the anti-inflammatory transcription factor PPAR gamma and attenuation of microglia activation. Antinociceptive effects are lost by combined inhibition of CB1 and CB2 receptors and partially abolished in CB1 receptor deficient mice. R-flurbiprofen does however not cause changes of core body temperature which is a typical indicator of central effects of cannabinoid-1 receptor agonists. Conclusion: Our results suggest that R-flurbiprofen improves the endogenous mechanisms to regain stability after axonal injury and to fend off chronic neuropathic pain by modulating the endocannabinoid system and thus constitutes an attractive, novel therapeutic agent in the treatment of chronic, intractable pain
Site-Specific and Time-Dependent Activation of the Endocannabinoid System after Transection of Long-Range Projections
Background: After focal neuronal injury the endocannabinioid system becomes activated and protects or harms neurons depending on cannabinoid derivates and receptor subtypes. Endocannabinoids (eCBs) play a central role in controlling local responses and influencing neural plasticity and survival. However, little is known about the functional relevance of eCBs in long-range projection damage as observed in stroke or spinal cord injury (SCI).
Methods: In rat organotypic entorhino-hippocampal slice cultures (OHSC) as a relevant and suitable model for investigating projection fibers in the CNS we performed perforant pathway transection (PPT) and subsequently analyzed the spatial and temporal dynamics of eCB levels. This approach allows proper distinction of responses in originating neurons (entorhinal cortex), areas of deafferentiation/anterograde axonal degeneration (dentate gyrus) and putative changes in more distant but synaptically connected subfields (cornu ammonis (CA) 1 region).
Results: Using LC-MS/MS, we measured a strong increase in arachidonoylethanolamide (AEA), oleoylethanolamide (OEA) and palmitoylethanolamide (PEA) levels in the denervation zone (dentate gyrus) 24 hours post lesion (hpl), whereas entorhinal cortex and CA1 region exhibited little if any changes. NAPE-PLD, responsible for biosynthesis of eCBs, was increased early, whereas FAAH, a catabolizing enzyme, was up-regulated 48hpl.
Conclusion: Neuronal damage as assessed by transection of long-range projections apparently provides a strong time-dependent and area-confined signal for de novo synthesis of eCB, presumably to restrict neuronal damage. The present data underlines the importance of activation of the eCB system in CNS pathologies and identifies a novel site-specific intrinsic regulation of eCBs after long-range projection damage
An endocannabinoid system is localized to the hypophysial pars tuberalis of Syrian hamsters and responds to photoperiodic changes
Evaluation of humanizing actions developed in pediatrics at the Hospital de ClÃnicas de Porto Alegre
A humanização compreende a valorização dos diferentes sujeitos implicados no processo de produção de saúde, o fomento da autonomia e do protagonismo desses sujeitos, o aumento do grau de co-responsabilidade, o estabelecimento de vÃnculos solidários e de participação coletiva no processo de gestão e atenção, assim como a identificação das necessidades sociais de saúde. Trata-se de uma pesquisa avaliativa, quantitativa, que buscou levantar as ações de humanização existentes no âmbito da internação pediátrica do Hospital de ClÃnicas de Porto Alegre. A pesquisa permitiu monitorar o processo de desenvolvimento e implantação de atividades extraassistenciais no âmbito da pediatria do Hospital de ClÃnicas. Nos resultados, podemos observar que, em relação à categoria públicoalvo, verificou-se que 64,2% dos programas abrangem crianças e adolescentes; 78,5%, familiares e acompanhantes; e 28,6%, equipe de saúde. Através deste trabalho, verificou-se que a avaliação das atividades desenvolvidas na internação pediátrica traduz o esforço desta equipe em buscar a humanização das suas ações. A inseparabilidade entre atenção e gestão, um dos princÃpios da polÃtica nacional de humanização, pode ser identificada através da valorização dos diferentes sujeitos implicados no processo de produção de saúde: usuários, trabalhadores e gestores.Humanization involves valuing different individuals implied in the health production process, fostering of autonomy and participation of these individuals, increased degree of co-responsibility, establishment of solidarity bonds and collective participation in the process of management and care, as well as identification of health social needs. This is an evaluative, quantitative study that aimed at surveying humanization actions within the scope of pediatric hospitalization at the Hospital de ClÃnicas de Porto Alegre. This study allowed us to monitor the development and implantation process of extra-care activities at a pediatric level at Hospital de ClÃnicas. Results concerning the target audience indicate that 64.2% of the programs are focused on children and adolescents; 78.5% on family members and companions; and 28.6% on health team. This study showed that the evaluation of activities developed in pediatric hospitalization translates the team’s effort in seeking humanization of its activities. Inseparability of care and management, one of the principles guiding the national humanization policy, can be identified through the value given to different individuals implied in the health production process: users, workers and managers