Effects of mild running on substantia nigra during early neurodegeneration

Moderate physical exercise acts at molecular and behavioural levels, such as interfering in neuroplasticity, cell death, neurogenesis, cognition and motor functions. Therefore, the aim of this study is to analyse the cellular effects of moderate treadmill running upon substantia nigra during early neurodegeneration. Aged male Lewis rats (9-month-old) were exposed to rotenone 1mg/kg/day (8 weeks) and 6 weeks of moderate treadmill running, beginning 4 weeks after rotenone exposure. Substantia nigra was extracted and submitted to proteasome and antioxidant enzymes activities, hydrogen peroxide levels and Western blot to evaluate tyrosine hydroxylase (TH), alpha-synuclein, Tom-20, PINK1, TrkB, SLP1, CRMP-2, Rab-27b, LC3II and Beclin-1 level. It was demonstrated that moderate treadmill running, practiced during early neurodegeneration, prevented the increase of alpha-synuclein and maintained the levels of TH unaltered in substantia nigra of aged rats. Physical exercise also stimulated autophagy and prevented impairment of mitophagy, but decreased proteasome activity in rotenone-exposed aged rats. Physical activity also prevented H2O2 increase during early neurodegeneration, although the involved mechanism remains to be elucidated. TrkB levels and its anterograde trafficking seem not to be influenced by moderate treadmill running. In conclusion, moderate physical training could prevent early neurodegeneration in substantia nigra through the improvement of autophagy and mitophagy

Plant Extracts Stimulate the Autophagy-Lysosomal Protein Clearance Pathway and Improve Brain Synapse Markers in an Explant Model of Age-Related Protein Accumulation Stress

Brain aging causes gradual protein accumulation pathology as clearance systems depreciate, leading to synaptic compromise, cognitive decline, and contributing as the primary risk factor of dementia. Removal of old and damaged proteins becomes less efficient with age, Poor nutrition is thought to influence cognitive aging and a growing number of studies point to natural products and a healthy diet as avenues for promoting brain health. The aim of this study was to screen a group of plant extracts for the ability to amplify the brain’s autophagy-lysosomal protein clearance pathway and to determine if such amplification reduces synaptic decline in a brain slice model of protein accumulation stress. Using slice cultures of rat hippocampus, a brain region vulnerable to Alzheimer’s disease and aging, plant extracts (1-500 µg/ml) were applied daily for 3 days, followed by assessment for changes in synaptic markers and components of theautophagy-lysosomal pathway as compared to vehicle-treated samples. The extract-infused hippocampal slice cultures were also treated with the lysosomal inhibitor chloroquine (CQN) and tested for protection against protein accumulation stress-induced synaptic compromise. American ginseng (P. quinquefolius) and bacopa (B. monnieri) extracts markedly enhanced the lysosomal protease cathepsin B (CatB). They both produced a nearly 4-fold increase in the 30-kDa active form of CatB (CatB-30), whereas only brain tissue treated with American ginseng exhibited a correlation between CatB levels and improved measures of the synaptic protein GluR1. Small increases in CatB-30 were produced by extracts from Panax ginseng and wild blueberry (V. myrtillus). Also a primary outcome, American ginseng-treated slices were less prone to synaptic decline due to CQN-mediated protein accumulation stress. Plant extracts differentially enrich CatB in hippocampal tissue in a manner that positively influences synaptic integrity. Enhancing the autophagy-lysosomal pathway protected brain synapses in a model of age-related deficiency in protein clearance activity, suggesting a need for additional studies to test for benefits in aged animals with cognitive impairment

Domain and Geometry Agnostic CNNs for Left Atrium Segmentation in 3D Ultrasound

Segmentation of the left atrium and deriving its size can help to predict and detect various cardiovascular conditions. Automation of this process in 3D Ultrasound image data is desirable, since manual delineations are time-consuming, challenging and observer-dependent. Convolutional neural networks have made improvements in computer vision and in medical image analysis. They have successfully been applied to segmentation tasks and were extended to work on volumetric data. In this paper we introduce a combined deep-learning based approach on volumetric segmentation in Ultrasound acquisitions with incorporation of prior knowledge about left atrial shape and imaging device. The results show, that including a shape prior helps the domain adaptation and the accuracy of segmentation is further increased with adversarial learning

Ecology and Geography of Plague Transmission Areas in Northeastern Brazil

Plague in Brazil is poorly known and now rarely seen, so studies of its ecology are difficult. We used ecological niche models of historical (1966-present) records of human plague cases across northeastern Brazil to assess hypotheses regarding environmental correlates of plague occurrences across the region. Results indicate that the apparently focal distribution of plague in northeastern Brazil is indeed discontinuous, and that the causes of the discontinuity are not necessarily only related to elevation—rather, a diversity of environmental dimensions correlate to presence of plague foci in the region. Perhaps most interesting is that suitable areas for plague show marked seasonal variation in photosynthetic mass, with peaks in April and May, suggesting links to particular land cover types. Next steps in this line of research will require more detailed and specific examination of reservoir ecology and natural history

Aß42-mediated proteasome inhibition and associated tau pathology in hippocampus are governed by a lysosomal response involving cathepsin B: Evidence for protective crosstalk between protein clearance pathways

Impaired protein clearance likely increases the risk of protein accumulation disorders including Alzheimer’s disease (AD). Protein degradation through the proteasome pathway decreases with age and in AD brains, and the Aß42 peptide has been shown to impair proteasome function in cultured cells and in a cell-free model. Here, Aß42 was studied in brain tissue to measure changes in protein clearance pathways and related secondary pathology. Oligomerized Aß42 (0.5–1.5 µM) reduced proteasome activity by 62% in hippocampal slice cultures over a 4-6-day period, corresponding with increased tau phosphorylation and reduced synaptophysin levels. Interestingly, the decrease in proteasome activity was associated with a delayed inverse effect, >2-fold increase, regarding lysosomal cathepsin B (CatB) activity. The CatB enhancement did not correspond with the Aß42-mediated phospho-tau alterations since the latter occurred prior to the CatB response. Hippocampal slices treated with the proteasome inhibitor lactacystin also exhibited an inverse effect on CatB activity with respect to diminished proteasome function. Lactacystin caused earlier CatB enhancement than Aß42, and no correspondence was evident between up-regulated CatB levels and the delayed synaptic pathology indicated by the loss of pre- and postsynaptic markers. Contrasting the inverse effects on the proteasomal and lysosomal pathways by Aß42 and lactacystin, such were not found when CatB activity was up-regulated two-fold with Z-Phe-Ala-diazomethylketone (PADK). Instead of an inverse decline, proteasome function was increased marginally in PADK-treated hippocampal slices. Unexpectedly, the proteasomal augmentation was significantly pronounced in Aß42-compromised slices, while absent in lactacystin-treated tissue, resulting in >2-fold improvement for nearly complete recovery of proteasome function by the CatB-enhancing compound. The PADK treatment also reduced Aß42-mediated tau phosphorylation and synaptic marker declines, corresponding with the positive modulation of both proteasome activity and the lysosomal CatB enzyme. These findings indicate that proteasomal stress contributes to AD-type pathogenesis and that governing such pathology occurs through crosstalk between the two protein clearance pathways

Inhibitor of Endocannabinoid Deactivation Protects Against In Vitro and In Vivo Neurotoxic Effects of Paraoxon

The anticholinesterase paraoxon (Pxn) is related to military nerve agents that increase acetylcholine levels, trigger seizures, and cause excitotoxic damage in the brain. In rat hippocampal slice cultures, high-dose Pxn was applied resulting in a presynaptic vulnerability evidenced by a 64% reduction in synapsin IIb (syn IIb) levels, whereas the postsynaptic protein GluR1 was unchanged. Other signs of Pxninduced cytotoxicity include the oxidative stress-related production of stable 4-hydroxynonenal (4-HNE)-protein adducts. Next, the Pxn toxicity was tested for protective effects by the fatty acid amide hydrolase (FAAH) inhibitor AM5206, a compound linked to enhanced repair signaling through the endocannabinoid pathway. The Pxn-mediated declines in syn IIb and synaptophysin were prevented by AM5206 in the slice cultures. To test if the protective results in the slice model translate to an in vivo model, AM5206 was injected i.p. into rats, followed immediately by subcutaneous Pxn administration. The toxin caused a pathogenic cascade initiated by seizure events, leading to presynaptic marker decline and oxidative changes in the hippocampus and frontal cortex. AM5206 exhibited protective effects including the reduction of seizure severity by 86%, and improving balance and coordination measured 24 h post-insult. As observed in hippocampal slices, the FAAH inhibitor also prevented the Pxn-induced loss of syn IIb in vivo. In addition, the AM5206 compound reduced the 4-HNE modifications of proteins and the ß1 integrin activation events both in vitro and in vivo. These results indicate that Pxn exposure produces oxidative and synaptic toxicity that leads to the behavioral deficits manifested by the neurotoxin. In contrast, the presence of FAAH inhibitor AM5206 offsets the pathogenic cascade elicited by the Pxn anticholinesterase

The depression in visual impairment trial (DEPVIT): trial design and protocol

<b>Background</b> The prevalence of depression in people with a visual disability is high but screening for depression and referral for treatment is not yet an integral part of visual rehabilitation service provision. One reason for this may be that there is no good evidence about the effectiveness of treatments in this patient group. This study is the first to evaluate the effect of depression treatments on people with a visual impairment and co morbid depression.<p></p> <b>Methods/design</b> The study is an exploratory, multicentre, individually randomised waiting list controlled trial. Participants will be randomised to receive Problem Solving Therapy (PST), a ‘referral to the GP’ requesting treatment according to the NICE’s ‘stepped care’ recommendations or the waiting list arm of the trial. The primary outcome measure is change (from randomisation) in depressive symptoms as measured by the Beck’s Depression Inventory (BDI-II) at 6 months. Secondary outcomes include change in depressive symptoms at 3 months, change in visual function as measured with the near vision subscale of the VFQ-48 and 7 item NEI-VFQ at 3 and 6 months, change in generic health related quality of life (EQ5D), the costs associated with PST, estimates of incremental cost effectiveness, and recruitment rate estimation.<p></p> <b>Discussion</b> Depression is prevalent in people with disabling visual impairment. This exploratory study will establish depression screening and referral for treatment in visual rehabilitation clinics in the UK. It will be the first to explore the efficacy of PST and the effectiveness of NICE’s ‘stepped care’ approach to the treatment of depression in people with a visual impairment.<p></p&gt

Peripheral biomarkers to diagnose obstructive sleep apnea in adults: A systematic review and meta-analysis

Background: Obstructive Sleep Apnea (OSA) has been recognized as a major health concern worldwide, given its increasing prevalence, difficulties in diagnosis and treatment, and impact on health, economy, and society. Clinical guidelines highlight the need of biomarkers to guide OSA clinical decision-making, but so far, without success. In this systematic review and meta-analysis, registered on the International Prospective Register of Systematic Reviews database (ID CRD42020132556), we proposed to gather and further explore candidates identified in the literature as potential OSA biomarkers. Methods: Search strategies for eight different databases (PubMed/Medline, Cochrane Library, Biblioteca Virtual da Saúde, Web of Science, EMBASE, World Intellectual Property Organization database, and bioRxiV and medRxiV Preprint Servers) were developed. We identified studies exploring potential biomarkers of OSA, in peripheral samples of adults, with and without OSA, with no comorbidities defined in study inclusion criteria, published after the last systematic review and meta-analysis conducted on OSA biomarkers, until May 31st, 2020. Risk of bias was assessed through the 14-item Quality Assessment Tool for Diagnostic Accuracy Studies. Demographic, clinical, and candidate biomarkers' data were collected and analyzed via random effects meta-analyses. Findings: Among the 1512 unique studies screened, 120 met the inclusion criteria and 16 studies with low risk of bias were selected for meta-analyses. The selected 16 studies enrolled a total of 2156 participants, from which 1369 were diagnosed with OSA and 787 were disease-free controls. The assessed variables showed high heterogeneity. From the 38 biomarker candidates evaluated, only two were evaluated in more than one study. Most studies pinpointed candidates with more potential for OSA prognosis. ADAM29, FLRT2 and SLC18A3 mRNA levels in PBMCs, Endocan and YKL-40 levels in serum, and IL-6 and Vimentin levels in plasma revealed the most promising candidates for OSA diagnosis. Interpretation: Although the current systematic review and meta-analysis allowed us to identify candidates to further explore as potential biomarkers in future studies, it is evident that OSA biomarkers research is still at an early stage. Most findings derive from small-size single-center study cohorts and single-candidate studies. We point several gaps in current OSA biomarker research that may guide into new directions and approaches towards the identification of OSA biomarkers.info:eu-repo/semantics/publishedVersio

Newborns in the emergency department: a one-year study

Introdução: Os serviços de urgência pediátrica são ambientes particularmente deletérios para os recém-nascidos. A identifica - ção precoce da doença neste grupo é fundamental, uma vez que o atraso diagnóstico pode estar associado a consequências graves. A maioria dos sistemas de triagem utilizados nos serviços de urgência pediátrica não possui algoritmos específicos para os recém-nascidos. Este estudo teve como objetivos caracterizar os recém-nascidos que recorreram ao serviço de urgência pediátrica, analisar a sua categorização pelo Sistema de Triagem de Manchester e identificar fatores de risco associados ao internamento. Métodos: Estudo retrospetivo efetuado pela análise dos dados de recém-nascidos admitidos no serviço de urgência pediátrica no ano de 2012. Resultados: Foram incluídos 779 recém-nascidos com idade média de 16,78 dias. Os principais diagnósticos de admissão foram as infeções respiratórias (21,9%) e a cólica do lactente (21%). Ficaram internados 22,2%, sendo os principais motivos as infe - ções respiratórias baixas (19,7%), os episódios de apparent life threatening event (15%) e as gastroenterites agudas (10,8%). A presença de hipoxemia e a realização de exames complementares no serviço de urgência pediátrica associaram-se a maior taxa de internamento (p = 0,001), assim como a atribuição de nível de prioridade “urgente”, “muito urgente” ou “emergente” pelo Sistema de Triagem de Manchester (p = 0,001). Discussão: O recurso dos recém-nascidos ao serviço de urgência pediátrica neste hospital ocorre maioritariamente por situa- ções de doença aguda. Os diagnósticos de admissão mais frequentes apresentam pouca gravidade clínica, já que contribuem pouco para o número de internamentos. Verifica-se uma correlação entre o nível de prioridade atribuído pelo Sistema de Triagem de Manchester e a necessidade de internamento neste grupo etário.Background: Paediatric emergency departments are par- ticularly deleterious environments for newborns. Early identification of disease in this group is essential since diag - nostic delay may be associated with serious consequences. Most triage systems used in emergency departments have no specific algorithms for newborns. This study aims to characterise newborns admitted to an emergency depart- ment and to identify factors associated with the need for hospitalisation. It also aims to analyse the categorisation of newborns by the Manchester Triage System. Methods: This was a retrospective study of newborns admitted to the paediatric emergency department during 2012. Results: A total of 779 newborns were included, with a mean age of 16.78 days. The main causes of admission were respiratory infections (21.9%) and infant colic (21%). A total of 22.2% newborns were hospitalised, the main motives being lower respiratory tract infections (19.7%), apparent life-threatening events (15%) and acute gastro- enteritis (10.8%). Hypoxaemia and and complementary exams were associated with a higher hospitalisation rate (p=0.001). Categorisation as urgent, very urgent or emer- gent priority by the Manchester Triage System was also associated with higher hospitalisation rates (p=0.001). Discussion: Newborns went to the paediatric emer- gency department mainly because of acute disease. The most common admission diagnoses were not clinically severe, since they contributed little to the hospitalisa - tion rate. There was a correlation between the priority level assigned by the Manchester Triage System and the need for hospitalisation in this age-group

The Value of Right Ventricular Longitudinal Strain in the Evaluation of Adult Patients With Repaired Tetralogy of Fallot: a New Tool for a Contemporary Challenge

OBJECTIVE: The role of right ventricular longitudinal strain for assessing patients with repaired tetralogy of Fallot is not fully understood. In this study, we aimed to evaluate its relation with other structural and functional parameters in these patients. METHODS: Patients followed-up in a grown-up CHD unit, assessed by transthoracic echocardiography, cardiac MRI, and treadmill exercise testing, were retrospectively evaluated. Right ventricular size and function and pulmonary regurgitation severity were assessed by echocardiography and MRI. Right ventricular longitudinal strain was evaluated in the four-chamber view using the standard semiautomatic method. RESULTS: In total, 42 patients were included (61% male, 32±8 years). The mean right ventricular longitudinal strain was -16.2±3.7%, and the right ventricular ejection fraction, measured by MRI, was 42.9±7.2%. Longitudinal strain showed linear correlation with tricuspid annular systolic excursion (r=-0.40) and right ventricular ejection fraction (r=-0.45) (all p<0.05), which in turn showed linear correlation with right ventricular fractional area change (r=0.50), pulmonary regurgitation colour length (r=0.35), right ventricular end-systolic volume (r=-0.60), and left ventricular ejection fraction (r=0.36) (all p<0.05). Longitudinal strain (β=-0.72, 95% confidence interval -1.41, -0.15) and left ventricular ejection fraction (β=0.39, 95% confidence interval 0.11, 0.67) were independently associated with right ventricular ejection fraction. The best threshold of longitudinal strain for predicting a right ventricular ejection fraction of <40% was -17.0%. CONCLUSIONS: Right ventricular longitudinal strain is a powerful method for evaluating patients with tetralogy of Fallot. It correlated with echocardiographic right ventricular function parameters and was independently associated with right ventricular ejection fraction derived by MRI.info:eu-repo/semantics/publishedVersio