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Senior Project submitted to The Division of Arts of Bard College

Jornalismo na internet e as organizações Globo no mundo virtual: estudos de casos do G1, Globo.com, O Globo Online e Techtudo

Demonstra o desenvolvimento do jornalismo online no Brasil, representado pelas plataformas de notícias das Organizações Globo. Desta forma, são abordados assuntos como a evolução da Internet, assim como o não suprimento completo do jornal impresso, no cenário atual, perante uma sociedade conectada e exigente de informações mais completas, com a integração multimídia e de hiperlinks. A análise é elaborada por meio de quatro estudos de casos, assinalados por G1, Globo.com, O Globo online e TechTudo, além de dados absorvidos por meio de pesquisa, a fim de compreender o acesso diário aos veículos de notícias. O estudo aborda ainda questões fundamentais de design, como a fundamentação teórica da utilização das cores de sites, estruturação de grid, uso de fontes e demais quesitos do meio. Além disso, são destrinchadas notícias assinadas por profissionais de cada veículo, com o propósito de ter melhor conhecimento sobre o tipo de conteúdo oferecido para o internauta, apresentando seus prós e contras em comparação com os veículos impressos. Dessa forma, a análise busca apresentar de forma completa os quatro estudos de caso, verificando como é elaborada a aplicação das teorias abordadas. Por fim, a conclusão integraliza todos os pontos observados, tanto pela estruturação jornalística quanto pela linha de design implementada em cada site jornalístico, e observa as vantagens oferecidas pelo acesso de notícias por meio de veículos online, além dos contrapontos dos elementos faltantes, causados pela maturidade incompleta do conteúdo na plataforma no webjornalismo

Allosteric Modulation of NMDARs Reverses Patients' Autoantibody Effects in Mice

Background and Objectives To demonstrate that an analog (SGE-301) of a brain-derived cholesterol metabolite, 24(S)- hydroxycholesterol, which is a selective positive allosteric modulator (PAM) of NMDA re- ceptors (NMDARs), is able to reverse the memory and synaptic alterations caused by CSF from patients with anti-NMDAR encephalitis in an animal model of passive transfer of antibodies. Methods Four groups of mice received (days 1-14) patients' or controls' CSF via osmotic pumps connected to the cerebroventricular system and from day 11 were treated with daily sub- cutaneous injections of SGE-301 or vehicle (no drug). Visuospatial memory, locomotor activity (LA), synaptic NMDAR cluster density, hippocampal long-term potentiation (LTP), and paired-pulse facilitation (PPF) were assessed on days 10, 13, 18, and 26 using reported techniques. Results On day 10, mice infused with patients' CSF, but not controls' CSF, presented a significant visuospatial memory deficit, reduction of NMDAR clusters, and impairment of LTP, whereas LA and PPF were unaffected. These alterations persisted until day 18, the time of maximal deficits in this model. In contrast, mice that received patients' CSF but from day 11 were treated with SGE-301 showed memory recovery (day 13), and on day 18, all paradigms (memory, NMDAR clusters, and LTP) had reversed to values similar to those of controls. On day 26, no differences were observed among experimental groups. Discussion An oxysterol biology-based PAM of NMDARs is able to reverse the synaptic and memory deficits caused by CSF from patients with anti-NMDAR encephalitis. These findings suggest a novel adjuvant treatment approach that deserves future clinical evaluation

LGI1 antibodies alter Kv1.1 and AMPA receptors changing synaptic excitability, plasticity and memory

Leucine-rich glioma-inactivated 1 (LGI1) is a secreted neuronal protein that forms a trans-synaptic complex that includes the presynaptic disintegrin and metalloproteinase domain-containing protein 23 (ADAM23), which interacts with voltage-gated potassium channels Kv1.1, and the postsynaptic ADAM22, which interacts with AMPA receptors. Human autoantibodies against LGI1 associate with a form of autoimmune limbic encephalitis characterized by severe but treatable memory impairment and frequent faciobrachial dystonic seizures. Although there is evidence that this disease is immune-mediated, the underlying LGI1 antibody-mediated mechanisms are unknown. Here, we used patient-derived immunoglobulin G (IgG) antibodies to determine the main epitope regions of LGI1 and whether the antibodies disrupt the interaction of LGI1 with ADAM23 and ADAM22. In addition, we assessed the effects of patient-derived antibodies on Kv1.1, AMPA receptors, and memory in a mouse model based on cerebroventricular transfer of patient-derived IgG. We found that IgG from all patients (n = 25), but not from healthy participants (n = 20), prevented the binding of LGI1 to ADAM23 and ADAM22. Using full-length LGI1, LGI3, and LGI1 constructs containing the LRR1 domain (EPTP1-deleted) or EPTP1 domain (LRR3-EPTP1), IgG from all patients reacted with epitope regions contained in the LRR1 and EPTP1 domains. Confocal analysis of hippocampal slices of mice infused with pooled IgG from eight patients, but not pooled IgG from controls, showed a decrease of total and synaptic levels of Kv1.1 and AMPA receptors. The effects on Kv1.1 preceded those involving the AMPA receptors. In acute slice preparations of hippocampus, patch-clamp analysis from dentate gyrus granule cells and CA1 pyramidal neurons showed neuronal hyperexcitability with increased glutamatergic transmission, higher presynaptic release probability, and reduced synaptic failure rate upon minimal stimulation, all likely caused by the decreased expression of Kv1.1. Analysis of synaptic plasticity by recording field potentials in the CA1 region of the hippocampus showed a severe impairment of long-term potentiation. This defect in synaptic plasticity was independent from Kv1 blockade and was possibly mediated by ineffective recruitment of postsynaptic AMPA receptors. In parallel with these findings, mice infused with patient-derived IgG showed severe memory deficits in the novel object recognition test that progressively improved after stopping the infusion of patient-derived IgG. Different from genetic models of LGI1 deficiency, we did not observe aberrant dendritic sprouting or defective synaptic pruning as potential cause of the symptoms. Overall, these findings demonstrate that patient-derived IgG disrupt presynaptic and postsynaptic LGI1 signalling, causing neuronal hyperexcitability, decreased plasticity, and reversible memory deficits

Placental transfer of NMDAR antibodies causes reversible alterations in mice

Objective: To determine whether maternofetal transfer of NMDA receptor (NMDAR) antibodies has pathogenic effects on the fetus and offspring, we developed a model of placental transfer of antibodies. Methods: Pregnant C57BL/6J mice were administered via tail vein patients' or controls' immunoglobulin G (IgG) on days 14-16 of gestation, when the placenta is able to transport IgG and the immature fetal blood-brain barrier is less restrictive to IgG crossing. Immunohistochemical and DiOlistic (gene gun delivery of fluorescent dye) staining, confocal microscopy, standardized developmental and behavioral tasks, and hippocampal long-term potentiation were used to determine the antibody effects. Results: In brains of fetuses, patients' IgG, but not controls' IgG, bound to NMDAR, causing a decrease in NMDAR clusters and cortical plate thickness. No increase in neonatal mortality was observed, but offspring exposed in utero to patients' IgG had reduced levels of cell-surface and synaptic NMDAR, increased dendritic arborization, decreased density of mature (mushroom-shaped) spines, microglial activation, and thinning of brain cortical layers II-IV with cellular compaction. These animals also had a delay in innate reflexes and eye opening and during follow-up showed depressive-like behavior, deficits in nest building, poor motor coordination, and impaired social-spatial memory and hippocampal plasticity. Remarkably, all these paradigms progressively improved (becoming similar to those of controls) during follow-up until adulthood. Conclusions: In this model, placental transfer of patients' NMDAR antibodies caused severe but reversible synaptic and neurodevelopmental alterations. Reversible antibody effects may contribute to the infrequent and limited number of complications described in children of patients who develop anti-NMDAR encephalitis during pregnancy

Allosteric modulation of NMDA receptors prevents the antibody effects of patients with anti-NMDAR encephalitis

Anti-N-Methyl-D-Aspartate Receptor (NMDAR) encephalitis is an immune-mediated disease characterized by a complex neuropsychiatric syndrome in association with an antibody-mediated decrease of NMDAR. About 85% of patients respond to immunotherapy (and removal of an associated tumor if it applies), but it often takes several months or more than 1 year for patients to recover. There are no complementary treatments, beyond immunotherapy, to accelerate this recovery. Previous studies showed that SGE-301, a synthetic analog of 24(S)-hydroxycholesterol, which is a potent, and selective positive allosteric modulator of NMDAR, reverted the memory deficit caused by phencyclidine (a non-competitive antagonist of NMDAR), and prevented the NMDAR dysfunction caused by patients' NMDAR antibodies in cultured neurons. An advantage of SGE-301 is that it is optimized for systemic delivery such that plasma and brain exposures are sufficient to modulate NMDAR activity. Here, we used SGE-301 to confirm that in cultured neurons it prevented the antibody-mediated reduction of receptors, and then we applied it to a previously reported mouse model of passive cerebroventricular transfer of patients' CSF antibodies. Four groups were established: mice receiving continuous (14-day) infusion of patients' or controls' CSF, treated with daily subcutaneous administration of SGE-301 or vehicle (no drug). The effects on memory were examined with the novel object location (NOL) test at different time points, and the effects on synaptic levels of NMDAR (assessed with confocal microscopy) and plasticity (long-term potentiation [LTP]) were examined in the hippocampus on day 18, which in this model corresponds to the last day of maximal clinical and synaptic alterations. As expected, mice infused with patients' CSF antibodies, but not those infused with controls' CSF, and treated with vehicle developed severe memory deficit without locomotor alteration, accompanied by a decrease of NMDAR clusters and impairment of LTP. All antibody-mediated pathogenic effects (memory, synaptic NMDAR, LTP) were prevented in the animals that were treated with SGE-301, despite that this compound did not antagonize antibody binding. Additional investigations on the potential mechanisms related to these SGE-301 effects showed that (1) in cultured neurons SGE-301 prolonged the decay time of NMDAR-dependent spontaneous excitatory postsynaptic currents suggesting a prolonged open time of the channel, and (2) it significantly decreased the internalization of antibody-bound receptors suggesting that additional, yet unclear mechanisms, contribute in keeping unchanged the surface NMDAR density. Overall, these findings suggest that SGE-301, or similar modulators of NMDAR, could potentially serve as complementary treatment for anti-NMDAR encephalitis and deserve future investigations

Passive experimental autoimmune encephalomyelitis in C57BL/6 with MOG: evidence of involvement of B cells

Experimental autoimmune encephalomyelitis (EAE) is the most relevant animal model to study demyelinating diseases such as multiple sclerosis. EAE can be induced by active (active EAE) or passive (at-EAE) transfer of activated T cells in several species and strains of rodents. However, histological features of at-EAE model in C57BL/6 are poorly described. The aim of this study was to characterize the neuroinflammatory and neurodegenerative responses of at-EAE in C57BL/6 mice by histological techniques and compare them with that observed in the active EAE model. To develop the at-EAE, splenocytes from active EAE female mice were harvested and cultured in presence of MOG 35-55 and IL-12, and then injected intraperitoneally in recipient female C57BL6/J mice. In both models, the development of EAE was similar except for starting before the onset of symptoms and presenting a higher EAE cumulative score in the at-EAE model. Spinal cord histological examination revealed an increased glial activation as well as more extensive demyelinating areas in the at-EAE than in the active EAE model. Although inflammatory infiltrates composed by macrophages and T lymphocytes were found in the spinal cord and brain of both models, B lymphocytes were significantly increased in the at-EAE model. The co-localization of these B cells with IgG and their predominant distribution in areas of demyelination would suggest that IgG-secreting B cells are involved in the neurodegenerative processes associated with at-EAE

Application of infrared thermography in computer aided diagnosis

The invention of thermography, in the 1950s, posed a formidable problem to the research community: What is the relationship between disease and heat radiation captured with Infrared (IR) cameras? The research community responded with a continuous effort to find this crucial relationship. This effort was aided by advances in processing techniques, improved sensitivity and spatial resolution of thermal sensors. However, despite this progress fundamental issues with this imaging modality still remain. The main problem is that the link between disease and heat radiation is complex and in many cases even non-linear. Furthermore, the change in heat radiation as well as the change in radiation pattern, which indicate disease, is minute. On a technical level, this poses high requirements on image capturing and processing. On a more abstract level, these problems lead to inter-observer variability and on an even more abstract level they lead to a lack of trust in this imaging modality. In this review, we adopt the position that these problems can only be solved through a strict application of scientific principles and objective performance assessment. Computing machinery is inherently objective; this helps us to apply scientific principles in a transparent way and to assess the performance results. As a consequence, we aim to promote thermography based Computer-Aided Diagnosis (CAD) systems. Another benefit of CAD systems comes from the fact that the diagnostic accuracy is linked to the capability of the computing machinery and, in general, computers become ever more potent. We predict that a pervasive application of computers and networking technology in medicine will help us to overcome the shortcomings of any single imaging modality and this will pave the way for integrated health care systems which maximize the quality of patient care

Regional and experiential differences in surgeon preference for the treatment of cervical facet injuries: a case study survey with the AO Spine Cervical Classification Validation Group

Purpose: The management of cervical facet dislocation injuries remains controversial. The main purpose of this investigation was to identify whether a surgeon’s geographic location or years in practice influences their preferred management of traumatic cervical facet dislocation injuries. Methods: A survey was sent to 272 AO Spine members across all geographic regions and with a variety of practice experience. The survey included clinical case scenarios of cervical facet dislocation injuries and asked responders to select preferences among various diagnostic and management options. Results: A total of 189 complete responses were received. Over 50% of responding surgeons in each region elected to initiate management of cervical facet dislocation injuries with an MRI, with 6 case exceptions. Overall, there was considerable agreement between American and European responders regarding management of these injuries, with only 3 cases exhibiting a significant difference. Additionally, results also exhibited considerable management agreement between those with ≤ 10 and > 10 years of practice experience, with only 2 case exceptions noted. Conclusion: More than half of responders, regardless of geographical location or practice experience, identified MRI as a screening imaging modality when managing cervical facet dislocation injuries, regardless of the status of the spinal cord and prior to any additional intervention. Additionally, a majority of surgeons would elect an anterior approach for the surgical management of these injuries. The study found overall agreement in management preferences of cervical facet dislocation injuries around the globe