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Summary: Age-related alterations in the immune system are starting to emerge as key contributors to impairments found in aged organs. A decline in regenerative capacity is a hallmark of tissue aging; however, the contribution of immune aging to regenerative failure is just starting to be explored. Here, we apply a strategy combining single-cell RNA sequencing with flow cytometry, histological analysis, and functional assays to perform a complete analysis of the immune environment of the aged regenerating skeletal muscle on a time course following injury with single-cell resolution. Our results reveal an unanticipated complexity and functional heterogeneity in immune populations within the skeletal muscle that have been regarded as homogeneous. Furthermore, we uncover a profound remodeling of both myeloid and lymphoid compartments in aging. These discoveries challenge established notions on immune regulation of skeletal muscle regeneration, providing a set of potential targets to improve skeletal muscle health and regenerative capacity in aging.

Privacy violations concern many social networking sites users. Here, we seek to understand how it might affect SNS use reduction. In Study 1, we untangle a mechanism through which this concern drives SNS use reduction. To do so, we leverage the stressor-strain-outcome framework (SSO) and examine whether privacy concerns can trigger fatigue, which in turn motivates intended SNS reduction. To extend this view, we theorize on how SNS addiction can moderate the abovementioned framework. This first study shows that privacy can indirectly lead to SNS use reduction and that addiction negatively impacts the adoption of healthy SNS use. In Study 2, we build on fear appeal theories to examine whether privacy fear appeals can drive actual SNS use reduction. It was demonstrated that privacy fear appeals effectively promote a limited and more controlled SNS use.

Abstract Staphylococcus aureus is a frequent agent of bacteraemia. This bacterium has a variety of virulence traits that allow the establishment and maintenance of infection. This study explored the virulence profile of S. aureus strains causing paediatric bacteraemia (SAB) in Manhiça district, Mozambique. We analysed 336 S. aureus strains isolated from blood cultures of children younger than 5 years admitted to the Manhiça District Hospital between 2001 and 2019, previously characterized for antibiotic susceptibility and clonality. The strains virulence potential was evaluated by PCR detection of the Panton-Valentine leucocidin (PVL) encoding genes, lukS-PV/lukF-PV, assessment of the capacity for biofilm formation and pathogenicity assays in Galleria mellonella. The overall carriage of PVL-encoding genes was over 40%, although reaching ~ 70 to 100% in the last years (2014 to 2019), potentially linked to the emergence of CC152 lineage. Strong biofilm production was a frequent trait of CC152 strains. Representative CC152 and CC121 strains showed higher virulence potential in the G. mellonella model when compared to reference strains, with variations within and between CCs. Our results highlight the importance of monitoring the emergent CC152-MSSA-PVL+ and other lineages, as they display important virulence traits that may negatively impact the management of SAB paediatric patients in Manhiça district, Mozambique.

Threatened benthic ecosystems need urgent tools for effective bioassessment and relevant management. EU Marine Strategy Framework Directive (MSFD) obligates member states to achieve GES (Good Environmental Status) for 11 descriptors of environmental state (MSFD; 2008/56/EC). From all of the descriptors, D4 that focuses on Food Webs is the most functional-oriented indicator, but also the most challenging to implement due to our limited knowledge on benthic interactions. Particularly, it is still unclear how spatially and temporally regulated abiotic variables determine the entire benthic food webs, and which benthic food web attributes best respond to these spatially and temporally derived environmental variations. To fill this gap, we measured the natural isotopic ratios (δ13C and δ15N) of macrobenthic organisms and their food sources and build twelve food web topologies across three distinct sites (Navigator, Gambia, Tróia) in summer and winter during two consecutive years. To assess these food web topologies, we applied isotopic metrics, further integrated with univariate and multivariate analysis to find food web-based indicators that best respond to these spatial and temporal variability.We found clear spatial patterns associated to an increase in primary production and quantity and quality of organic matter (OM). Sites with higher organic load and less quality OM (Navigator and Gambia) had simpler food webs, likely associated to high abundance of opportunistic meiobenthic species. Site located inside protected area (Tróia) with high quality OM had the most complex food web characterized by high diversity of specialist consumers that used more efficiently available resources. Similarity metrics were valuable complementary tool that helped to further disentangle the causes of spatial variability, in this case distinguishing between two food webs (Navigator and Gambia) that had similar structures but different resource utilization.The temporal patterns were not so evident than the spatial patterns, although significant differences were reported between sampling occasions for the same metrics (maximum trophic position and the percentage of carnivores and omnivores, p

Mixed connective tissue disease is an autoimmune disorder with overlapping features of systemic lupus erythematosus, systemic sclerosis and polymyositis. Cardiac involvement is common, being pericarditis the most frequent manifestation, as also pulmonary hypertension. The authors present a case of a woman with one year of symptoms of polyarthritis and myalgia with gradual muscle weakness and weight loss, with severe impaired mobility in the last months. The initial evaluation showed an inflammatory systemic condition with an infiltrative pattern in echocardiogram, with pulmonary hypertension, that was confirmed by cardiac magnetic resonance. After an extensive study, where infiltrative cardiomyopathies were a differential diagnosis, the patient meet criteria to mixed connective disease with signs of pulmonary hypertension and an atypical cardiac involvement. Immunosuppressive treatment and rehabilitation were initiated and one year after the patient remains asymptomatic without any limitations.

Polθ has been recently identified as a therapeutic target in cancer but specific inhibitors are currently unavailable. Here, the authors identify small molecule inhibitors of Polθ’s polymerase activity which elicit BRCA1/2 synthetic lethality, enhance the effect of PARP inhibitors and target PARP inhibitor resistance caused by 53BP1/Shieldin pathway defects.

Objectives: Multiparametric magnetic resonance imaging (mpMRI) is a useful tool to diagnose prostate cancer (PCa) but its cost is not negligible. In order to reduce costs and minimize time to diagnosis, it is necessary to establish which patients benefit the most from doing mpMRI prior to prostate biopsy (PB). Our aim was to test if mpMRI still predicts PCa and clinically significant PCa (csPCa) in patients with high clinical suspicion of cancer, defined as prostate specific antigen (PSA) > 10 ng/ml, PSA-Density (PSAD) > 0.15 ng/ml/cc or suspicious digital rectal examination (DRE). Materials and methods: We retrospectively collected data on 206 patients who underwent mpMRI before PB at our Department from January 2017 to July 2018. mpMRI results were classified using Prostate Imaging Reporting and Data System (PI-RADS) version 2. In primary analysis, we evaluated the association of mpMRI with PCa and csPCa and stratified this model for low and high clinical suspicion of cancer. In secondary analysis, we determined the rate of negative PB results in patients with high suspicion of cancer and compared theses rates with those obtained if only those with PI-RADS 3-5 would be biopsied. Results: In primary analysis and overall, mpMRI was predictive of PCa and csPCa. In stratified analysis, mpMRI was still significantly associated with csPCa in patients with PSA > 10 ng/ml and PSAD > 0.15 ng/ml/cc, but not in those with suspicious DRE. In secondary analysis, negative result rates were lower if only patients with PI-RADS 3-5 were biopsied, even in subgroups with high suspicion of cancer based on PSA and PSAD. In patients with suspicious DRE, however, the rate of negative results did not change significantly if only patients with PI-RADS 3-5 were biopsied. Conclusions: mpMRI is still useful in predicting csPCa in patients with PSA > 10 ng/mL and PSAD > 0.15 ng/ml/cc. If DRE is suspicious, though, mpMRI might be no longer useful in the prediction of PCa.

The respiratory tract is constantly exposed to pathogens that require iron for proliferation and virulence. Pulmonary iron levels are increased in several lung diseases and associated with increased susceptibility to infections. However, regulation of lung iron homeostasis and its cross talk to pulmonary immune responses are largely unexplored. Here we investigated how increased lung iron levels affect the early pulmonary inflammatory response. We induced acute local pulmonary inflammation via aerosolized LPS in a mouse model of hereditary hemochromatosis type 4 (Slc40a1C326S/C326S), which is hallmarked by systemic and pulmonary iron accumulation, specifically in alveolar macrophages. We show that Slc40a1C326S/C326S mice display a mild attenuation in the LPS-induced pulmonary inflammatory response, with a reduced upregulation of some pro-inflammatory cytokines and chemokines. Despite mildly reduced cytokine levels, there is no short-term impairment in the recruitment of neutrophils into the bronchoalveolar space. These data suggest that increased pulmonary iron levels do not strongly alter the acute inflammatory response of the lung.

Retinal homeostasis relies on intricate coordination of cell death and survival in response to stress and damage. Signaling mechanisms that coordinate this process in the adult retina remain poorly understood. Here we identify Decapentaplegic (Dpp) signaling in Drosophila and its mammalian homologue Transforming Growth Factor-beta (TGFβ) superfamily, that includes TGFβ and Bone Morphogenetic Protein (BMP) signaling arms, as central mediators of retinal neuronal death and tissue survival following acute damage. Using a Drosophila model for UV-induced retinal damage, we show that Dpp released from immune cells promotes tissue loss after UV-induced retinal damage. Interestingly, we find a dynamic response of retinal cells to this signal: in an early phase, Dpp-mediated stimulation of Saxophone/Smox signaling promotes apoptosis, while at a later stage, stimulation of the Thickveins/Mad axis promotes tissue repair and survival. This dual role is conserved in the mammalian retina through the TGFβ/BMP signaling, as supplementation of BMP4 or inhibition of TGFβ using small molecules promotes retinal cell survival, while inhibition of BMP negatively affects cell survival after light-induced photoreceptor damage and NMDA induced inner retinal neuronal damage. Our data identify key evolutionarily conserved mechanisms by which retinal homeostasis is maintained.

Emerging evidence suggests that pulmonary iron accumulation is implicated in a spectrum of chronic lung diseases. However, the mechanism(s) involved in pulmonary iron deposition and its role in the in vivo pathogenesis of lung diseases remains unknown. Here we show that a point mutation in the murine ferroportin gene, which causes hereditary hemochromatosis type 4 (Slc40a1C326S), increases iron levels in alveolar macrophages, epithelial cells lining the conducting airways and lung parenchyma, and in vascular smooth muscle cells. Pulmonary iron overload is associated with oxidative stress, restrictive lung disease with decreased total lung capacity and reduced blood oxygen saturation in homozygous Slc40a1C326S/C326S mice compared to wild-type controls. These findings implicate iron in lung pathology, which is so far not considered a classical iron-related disorder.

No Estado de São Paulo a década de 1960 foi marcada pela implantação de diversos processos de renovação educacional e ao mesmo tempo se ultimava o processo de tramitação do projeto da Lei de Diretrizes e Bases da Educação Nacional. Em ambos os casos o debate educacional era perpassado por questões políticas atinentes à perspectiva de redemocratização da sociedade brasileira, colocada pelo Pós-Guerra e pelo término da ditadura Vargas. Seria plausível conceber articulações entre os dois tipos de processo, mas, ao contrário, o que se verificava eram discrepâncias. Este trabalho analisa essas discrepâncias visando discutir os conflitos que se estabeleceram entre a expectativa de fazer da educação um suporte para a modernização econômica e as concepções segundo as quais a educação deveria, antes de tudo, promover a inserção da maioria da população no processo de construção de uma sociedade democrática.

O topiramato é um fármaco antiepilético usado no tratamento da epilepsia, estabilização do humor e prevenção da enxaqueca. Habitualmente bem tolerado, está associado pouco frequentemente a efeitos secundários oftalmológicos, tais como miopização e glaucoma agudos. É relatado o caso clinico de uma adolescente de 17anos, medicada com topiramato, que recorreu ao serviço de urgência por diminuição súbita da acuidade visual (AV) bilateral. No exame inicial constatou-se miopização e a biomicroscopia ultrassónica (UBM) revelou efusão uveal e edema do corpo ciliar com anteriorização do diafragma iris-cristalino e estreitamento angular bilateral, tendo sido suspenso o topiramato. Um mês após a interrupção a doente demonstrou reversão do quadro para emetropização e normalização das estruturas anatómicas, confirmada pela UBM. Os autores pretendem alertar para as complicações oftalmológicas de um fármaco amplamente usado, ressaltando a importância de um diagnóstico precoce evitando graves consequências, nomeadamente evolução para glaucoma agudo e potencial perda da AV.

Regeneration is an important process in multicellular organisms, responsible for homeostatic renewal and repair of different organs after injury. Immune cell activation is observed at early stages of the regenerative response and its regulation is essential for regenerative success. Thus, immune regulators play central roles in optimizing regenerative responses. Neurotrophic factors (NTFs) are secreted molecules, defined by their ability to support neuronal cell types. However, emerging evidence suggests that they can also play important functions in the regulation of immune cell activation and tissue repair. Here we discuss the literature supporting a role of NTFs in the regulation of inflammation and regeneration. We will focus, in particular, in the emerging roles of mesencephalic astrocyte-derived neurotrophic factor (MANF) and cerebral dopamine neurotrophic factor (CDNF) in the regulation of immune cell function and in the central role that immune modulation plays in their biological activity in vivo. Finally, we will discuss the potential use of these factors to optimize regenerative success in vivo, both within and beyond the nervous system.

Joint hypermobility syndrome (JHS) is a hereditary connective tissue disorder characterized by symptomatic generalized joint hypermobility. Other features such as luxations and subluxations, periarticular lesions and cutaneous or other organ manifestations due to collagen defects are included in JHS clinical criteria. JHS may be clinically indistinct from Ehlers-Danlos syndrome hypermobility type (EDS). We report the case of a 14 year old male patient, with chronic low back pain and generalized joint hypermobility. He also presented a marfanoid habitus, hand joint alterations and striae in the right dorsal region. He fulfilled the Brighton Criteria therefore, after excluding other connective tissue diseases, the diagnosis of JHS was established. JHS is an underestimated and underdiagnosed disease, and must be contemplated in front of musculoskeletal pain associated with generalized hypermobility. The authors describe this case highlighting the importance of looking for signs and symptoms which allow the earlier diagnosis and management.

Disorders of iron metabolism are largely attributed to an excessive or insufficient expression of hepcidin, the master regulator of systemic iron homeostasis. Here, we investigated whether drugs targeting genetic regulators of hepcidin can affect iron homeostasis. We focused our efforts on drugs approved for clinical use to enable repositioning strategies and/or to reveal iron-related side effects of widely prescribed therapeutics. To identify hepcidin-modulating therapeutics, we re-evaluated data generated by a genome-wide RNAi screen for hepcidin regulators. We identified ‘druggable’ screening hits and validated those by applying RNAi of potential drug targets and small-molecule testing in a hepatocytic cell line, in primary murine and human hepatocytes and in mice. We initially identified spironolactone, diclofenac, imatinib and Suberoylanilide hydroxamic acid (SAHA) as hepcidin modulating drugs in cellular assays. Among these, imatinib and spironolactone further suppressed liver hepcidin expression in mice. Our results demonstrate that a commonly used anti-hypertensive drug, spironolactone, which is prescribed for the treatment of heart failure, acne and female hirsutism, as well as imatinib, a first-line, lifelong therapeutic option for some frequent cancer types suppress hepcidin expression in cultured cells and in mice. We expect these results to be of relevance for patient management, which needs to be addressed in prospective clinical studies.

Mice lacking Cdk6 kinase activity suffer from mild anemia accompanied by elevated numbers of Ter119+ cells in the bone marrow. The animals show hardly any alterations in erythroid development, indicating that Cdk6 is not required for proliferation and maturation of erythroid cells. There is also no difference in stress erythropoiesis following hemolysis in vivo. However, Cdk6−/− erythrocytes have a shortened lifespan and are more sensitive to mechanical stress in vitro, suggesting differences in cytoskeletal architecture. Erythroblasts contain both Cdk4 and Cdk6, while mature erythrocytes apparently lack Cdk4 and their Cdk6 is partly associated with the cytoskeleton. We used mass spectrometry to show that Cdk6 interacts with a number of proteins involved in cytoskeleton organization. Cdk6−/− erythroblasts show impaired F-actin formation and lower levels of gelsolin, which interacts with Cdk6. We also found that Cdk6 regulates the transcription of a panel of genes involved in actin (de-)polymerization. Cdk6-deficient cells are sensitive to drugs that interfere with the cytoskeleton, suggesting that our findings are relevant to the treatment of patients with anemia – and may be relevant to cancer patients treated with the new generation of CDK6 inhibitors.

Natural toxins such as those produced by freshwater cyanobacteria have been regarded as an emergent environmental threat. However, the impact of these water contaminants in agriculture is not yet fully understood. The aim of this work was to investigate microcystin-LR (MC-LR) toxicity in Lycopersicon esculentum and the toxin accumulation in this horticultural crop. Adult plants (2 month-old) grown in a greenhouse environment were exposed for 2 weeks to either pure MC-LR (100 μg/L) or Microcystis aeruginosa crude extracts containing 100 μg/L MC-LR. Chlorophyll fluorescence was measured, leaf proteome investigated with two-dimensional gel electrophoresis and Matrix Assisted Laser Desorption Ionization Time-of-Flight (MALDI-TOF)/TOF, and toxin bioaccumulation assessed by liquid chromatography-mass spectrometry (LC-MS)/MS. Variations in several protein markers (ATP synthase subunits, Cytochrome b6-f complex iron-sulfur, oxygen-evolving enhancer proteins) highlight the decrease of the capacity of plants to synthesize ATP and to perform photosynthesis, whereas variations in other proteins (ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit and ribose-5-phosphate isomerase) suggest an increase of carbon fixation and decrease of carbohydrate metabolism reactions in plants exposed to pure MC-LR and cyanobacterial extracts, respectively. MC-LR was found in roots (1635.21 μg/kg fw), green tomatoes (5.15–5.41 μg/kg fw), mature tomatoes (10.52–10.83 μg/kg fw), and leaves (12,298.18 μg/kg fw). The results raise concerns relative to food safety and point to the necessity of monitoring the bioaccumulation of water toxins in agricultural systems affected by cyanotoxin contamination.

A strong mechanistic link between the regulation of iron homeostasis and oxygen sensing is evident in the lung, where both systems must be properly controlled to maintain lung function. Imbalances in pulmonary iron homeostasis are frequently associated with respiratory diseases, such as chronic obstructive pulmonary disease and with lung cancer. However, the underlying mechanisms causing alterations in iron levels and the involvement of iron in the development of lung disorders are incompletely understood. Here, we review current knowledge about the regulation of pulmonary iron homeostasis, its functional importance, and the link between dysregulated iron levels and lung diseases. Gaining greater knowledge on how iron contributes to the pathogenesis of these diseases holds promise for future iron-related therapeutic strategies.

PURPOSE: The present a novel adenocarcinoma model in athymic mice. METHODS: Seven athymic mice were used. Colon diversion and distal fistula were made. Adenocarcinoma cells were inoculated in the submucosa of fistula. Tumor growth was monitored daily. Scintigraphy with 99mTc-MIBI was performed to identify the tumor. RESULTS: The model of distal colon cancer is feasible. Tumor detection was possible by both, macroscopically and molecular imaging. All resections demonstrated poorly differentiated tumors. Colon obstruction occurred in one case, similarly to evolution in human tumors of distal colon. CONCLUSION: The proposed model of distal colon cancer is feasible, allows for easy monitoring of tumoral growth by both, macroscopically and molecular imaging, and is suitable for studying the evolution of tumor with implementation of cytotoxic therapy in vivo.OBJETIVO: Apresentar novo modelo de adenocarcinoma distal em camundongos atímicos. MÉTODOS: Foram utilizados sete camundongos atímicos. Desvio do cólon distal e fístula foram feitas. Células de adenocarcinoma foram inoculadas na submucosa da fístula. O crescimento do tumor foi monitorado diariamente. Cintilografia com 99mTc-MIBI foi realizada para identificar o tumor. RESULTADOS: O modelo de câncer de cólon distal é viável. Detecção do tumor foi possível macroscopicamente e por imagem molecular. Todas as ressecções demonstraram tumores pouco diferenciados. Obstrução do cólon ocorreu em um caso, de forma semelhante à evolução em tumores humanos do cólon distal. CONCLUSÃO: O modelo de câncer do cólon distal proposto é viável, permite a monitorização fácil do crescimento tumoral macroscopicamente e por imagem molecular, sendo adequado para o estudo da evolução de tumor com aplicação de terapia citotóxica in vivo.

Objectives: to report a case of hypereosinophilic syndrome which presented clinically acute coronary syndrome. Materials and methods: we describe a case of a 69-year-old woman with acute coronary syndrome and peripheral hypereosinophilia. Results: the condition rapidly evolved to severe heart failure. Coronary disease was excluded by cardiac catheterization. Systemic corticosteroid therapy was initiated and further secondary causes of hypereosinophilia were excluded.

The proneural gene Atoh1 is crucial for the development of inner ear hair cells and it requires the function of the transcription factor Sox2 through yet unknown mechanisms. In the present work, we used the chicken embryo and HEK293T cells to explore the regulation of Atoh1 by Sox2. The results show that hair cells derive from Sox2-positive otic progenitors and that Sox2 directly activates Atoh1 through a transcriptional activator function that requires the integrity of Sox2 DNA binding domain. Atoh1 activation depends on Sox transcription factor binding sites (SoxTFBS) present in the Atoh1 3' enhancer where Sox2 directly binds, as shown by site directed mutagenesis and chromatin immunoprecipitation (ChIP). In the inner ear, Atoh1 enhancer activity is detected in the neurosensory domain and it depends on Sox2. Dominant negative competition (Sox2HMG-Engrailed) and mutation of the SoxTFBS abolish the reporter activity in vivo. Moreover, ChIP assay in isolated otic vesicles shows that Sox2 is bound to the Atoh1 enhancer in vivo. However, besides activating Atoh1, Sox2 also promotes the expression of Atoh1 negative regulators and the temporal profile of Atoh1 activation by Sox2 is transient suggesting that Sox2 triggers an incoherent feed-forward loop. These results provide a mechanism for the prosensory function of Sox2 in the inner ear. We suggest that sensory competence is established early in otic development through the activation of Atoh1 by Sox2, however, hair cell differentiation is prevented until later stages by the parallel activation of negative regulators of Atoh1 function.

Bronchial-associated lymphoid tissue (BALT) lymphoma is a rare condition that accounts for only 0.5-1% of all malignant lung tumours. We present the case of a 66-year-old man admitted with pneumonia for further study and therapy. Initially the sputum was positive for Mycobacterium tuberculosis complex using polymerase chain reaction technology and antituberculous therapy was initiated. Due to the lack of imagiological improvement, the patient underwent a pulmonary transthoracic biopsy that revealed BALT lymphoma. Months later, Mycobacterium chelonae was identified and specific therapy was started with clarithromycin and tobramycin, before initiating BALT treatment with cyclophosphamide. There are only a few documented cases of BALT lymphoma associated with Mycobacterium. In this case M. chelonae might have been present before BALT lymphoma, contributing as an immunologic stimulus, or appeared afterwards, in the neoplastic context. BALT has an indolent evolution with a good prognosis and that is the reason why some experts favour a “watchful waiting” option.