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  • Sanders Bager posted an update 1 day, 6 hours ago

    The transcription factor Nrf2 is a central regulator of anti-inflammatory and antioxidant mechanisms that contribute to the development and progression of various neurological disorders. Although the direct and indirect Nrf2 regulatory roles on inflammation have been reviewed in recent years, the in vivo evidence of Nrf2 function on lipopolysaccharide (LPS)-induced cognitive decline and characteristic alterations of reactive microglia and astrocytes remains incomplete. During the 3-5 days after LPS or saline injection, 5-6-month-old wildtype (WT) and Nrf2-/- C57BL/6 mice were subjected to the novel object recognition task. Immunohistochemistry staining was employed for analyses of brain cells. The Nrf2-/- mice displayed exacerbated LPS-induced cognition impairment (28.1 ± 9.6% in the discrimination index of the novel object recognition task), enhanced hippocampal reactive microgliosis and astrogliosis, and an increased expression level of the water channel transmembrane protein aquaporin 4 when compared with WT controls. In addition, similar overt effects of Nrf2 deficiency on LPS-induced characteristic alterations of brain cells were observed in the cortex and striatum regions of mice. In summary, this transgenic loss-of-function study provides direct in vivo evidence that highlights the functional importance of Nrf2 activation in regulating LPS-induced cognitive alteration, glial responses, and aquaporin 4 expression. This finding provides a better understanding of the complex nature of Nrf2 signaling and neuroprotection.Neonatal hypoxia-ischemia (HI) is the leading cause of mortality and morbidity in newborns, occurring in approximately 2% of live births. Neuroprotective actions of progesterone (PROG) have already been described in animal models of brain lesions. However, PROG actions on neonates are still controversial. Here, we treated male Wistar rats exposed to HI with PROG. Five experimental groups were defined (n = 6/group) according to the scheme of PROG administration (10 mg/kg) SHAM (animals submitted to a fictitious surgery, without ischemia induction, and maintained under normoxia), HI (animals undergoing HI), BEFORE (animals undergoing HI and receiving PROG immediately before HI), AFTER (animals undergoing HI and receiving PROG at 6 and 24 h after HI) and BEFORE/AFTER (animals undergoing HI and receiving PROG immediately before and 6 and 24 h after HI). At P14 (7 days following HI), the volumes of lesion of the cerebral hemisphere and the hippocampus ipsilateral to the cerebral ischemia were evaluated, along with p-Akt, cleaved caspase-3 and GFAP expression in the hippocampus. PROG reduces the loss of brain tissue caused by HI. Moreover, when administered after HI, PROG was able to increase p-Akt expression and reduce both cleaved caspase-3 and GFAP expression in the hippocampus. In summary, it was possible to observe a neuroprotective action of PROG on the brain of neonatal animals exposed to experimental HI. This is the first study suggesting PROG-dependent Akt activation is able to regulate negatively cleaved caspase-3 and GFAP expression protecting neonatal hypoxic-ischemic brain tissue from apoptosis and reactive gliosis.Miranda Fricker’s influential concept of epistemic injustice (Oxford University Press, Oxford, 2007) has recently seen application to many areas of interest, with an increasing body of healthcare research using the concept of epistemic injustice in order to develop both general frameworks and accounts of specific medical conditions and patient groups. This paper illuminates tensions that arise between taking steps to protect against committing epistemic injustice in healthcare, and taking steps to understand the complexity of one’s predicament and treat it accordingly. Work on epistemic injustice is therefore at risk of obfuscating legitimate and potentially fruitful inquiry. This paper uses Chronic Fatigue Syndrome/Myalgic Encephalomyelitis as a case study, but I suggest that the key problems identified could apply to other cases within healthcare, such as those classed as Medically Unexplained Illnesses, Functional Neurological Disorders and Psychiatric Disorders. BisindolylmaleimideI Future work on epistemic injustice in healthcare must recognise and attend to this tension to protect against unsatisfactory attempts to correct epistemic injustice.The main lysosomal protease cathepsin D (cathD) is essential for maintaining tissue homeostasis via its degradative function, and its loss leads to ceroid accumulation in the mammalian nervous system, which results in progressive neurodegeneration. Increasing evidence implies non-proteolytic roles of cathD in regulating various biological processes such as apoptosis, cell proliferation, and migration. Along these lines, we here showed that cathD is required for modulating dendritic architecture in the nervous system independent of its traditional degradative function. Upon cathD depletion, class I and class III arborization (da) neurons in Drosophila larvae exhibited aberrant dendritic morphology, including over-branching, aberrant turning, and elongation defects. Re-introduction of wild-type cathD or its proteolytically-inactive mutant dramatically abolished these morphological defects. Moreover, cathD knockdown also led to dendritic defects in the adult mushroom bodies, suggesting that cathD-mediated processes are required in both the peripheral and central nervous systems. Taken together, our results demonstrate a critical role of cathD in shaping dendritic architecture independent of its proteolytic function.PURPOSE To evaluate the detectability of AKA on aortic computed tomography angiography (CTA) using ultra-high-resolution computed tomography (UHRCT). MATERIALS AND METHODS Twenty-eight patients were enrolled. They underwent aortic CTA with UHRCT (UHRCTA) and had previously undergone aortic conventional CTA (CCTA). The injection protocol of UHRCTA was the same as that of CCTA. The bolus tracking technique was used. UHRCTA images were reconstructed with adaptive iterative dose reduction (strong) and with forward-projected model-based iterative reconstruction solution. The matrix size and slice thickness on UHRCT were 1024 and 0.25 mm, respectively, and those on conventional CT were 512 and 0.5 or 0.67 mm, respectively. The UHRCTA and CCTA images were visually compared by using four scales. A score of 4 or 3 indicated that the AKA was assessable. In this instance, the contrast-to-noise ratios of each UHRCTA were measured. The exposure dose and signal-to-noise ratios were also investigated. RESULTS The AKA visualization scores obtained with UHRCTA with forward-projected model-based iterative reconstruction solution were significantly higher than those with adaptive iterative dose reduction (p = 0.