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In vivo, cells interact with the extracellular matrix (ECM), which provides a multitude of biophysical and biochemical signals that modulate cellular behavior. Inspired by this, we explored a new methodology to develop a more physiomimetic polysaccharide-based matrix for 3D cell culture. Maleimide-modified alginate (AlgM) derivatives were successfully synthesized using DMTMM to activate carboxylic groups. Thiol-terminated cell-adhesion peptides were tethered to the hydrogel network to promote integrin binding. Rapid and efficient in situ hydrogel formation was promoted by thiol-Michael addition "click" chemistry via maleimide reaction with thiol-flanked protease-sensitive peptides. Alginate derivatives were further ionically crosslinked by divalent ions present in the medium, which led to greater stability and allowed longer cell culture periods. By tailoring alginate's biofunctionality we improved cell-cell and cell-matrix interactions, providing an ECM-like 3D microenvironment. We were able to systematically and independently vary biochemical and biophysical parameters to elicit specific cell responses, creating custom-made 3D matrices. DMTMM-mediated maleimide incorporation is a promising approach to synthesizing AlgM derivatives that can be leveraged to produce ECM-like matrices for a broad range of applications, from in vitro tissue modeling to tissue regeneration.
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Alginatos , Química Click , Matriz Extracelular , Hidrogéis , Maleimidas , Compostos de Sulfidrila , Humanos , Alginatos/química , Adesão Celular/efeitos dos fármacos , Reagentes de Ligações Cruzadas/química , Matriz Extracelular/metabolismo , Matriz Extracelular/química , Hidrogéis/química , Hidrogéis/síntese química , Maleimidas/química , Compostos de Sulfidrila/químicaRESUMO
Pool refuges are critical for maintaining stream fish diversity in increasingly intermittent streams. Yet, the patterns and drivers of beta diversity of native and non-native fish in pool refuges remain poorly known. Focusing on Mediterranean streams, we decomposed beta diversity of native and non-native fish into richness difference (RichDiff) and species replacement (Repl), and local (LCBD, LCBDRichDiff and LCBDRepl) and species (SCBD) contributions. We assessed the influence of environmental and spatial factors associated with drought and damming fragmentations on beta diversity components and LCBDs, and of local species richness and occupancy on LCBDs and SCBD, respectively. Overall, non-native species showed a more limited occupancy of pool refuges than native fish. RichDiff dominated beta diversity, though it was influenced by drought and damming fragmentations for native fish and local environment for non-native fish. Repl for native fish was slightly influenced by local environment, but for non-native fish was largely driven by drought and damming, albeit with a contribution of local environment as well. LCBD and LCBDRichDiff increased in pools in low order streams for native fish and at low elevations for non-native fish, and with high or low species richness. SCBD was higher for native species with intermediated pool occupancy, but for non-native species with low occupancy. Our results suggest that stream fragmentation may drive native species loss and non-native species replacement in pool refuges, and that environmental filtering may shape non-native species loss. Pools in lower order streams harbouring unique species-rich or species-poor assemblages should be prioritize for conservation and restoration, respectively, and pools at low elevation with unique non-native assemblages should deserve control efforts. We encourage the partitioning of beta diversity and individual analysis of native and non-native fish in intermittent streams, which may be key in stressing the importance of pool refuges in safeguarding native fish diversity.
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Biodiversidade , Secas , Peixes , Rios , Animais , Espécies Introduzidas , EcossistemaRESUMO
Introduction: Rare disorders that are genetically and clinically heterogeneous, such as mitochondrial diseases (MDs), have a challenging diagnosis. Nuclear genes codify most proteins involved in mitochondrial biogenesis, despite all mitochondria having their own DNA. The development of next-generation sequencing (NGS) technologies has revolutionized the understanding of many genes involved in the pathogenesis of MDs. In this new genetic era, using the NGS approach, we aimed to identify the genetic etiology for a suspected MD in a cohort of 450 Portuguese patients. Methods: We examined 450 patients using a combined NGS strategy, starting with the analysis of a targeted mitochondrial panel of 213 nuclear genes, and then proceeding to analyze the whole mitochondrial DNA. Results and Discussion: In this study, we identified disease-related variants in 134 (30%) analyzed patients, 88 with nuclear DNA (nDNA) and 46 with mitochondrial DNA (mtDNA) variants, most of them being pediatric patients (66%), of which 77% were identified in nDNA and 23% in mtDNA. The molecular analysis of this cohort revealed 72 already described pathogenic and 20 novel, probably pathogenic, variants, as well as 62 variants of unknown significance. For this cohort of patients with suspected MDs, the use of a customized gene panel provided a molecular diagnosis in a timely and cost-effective manner. Patients who cannot be diagnosed after this initial approach will be further selected for whole-exome sequencing. Conclusion: As a national laboratory for the study and research of MDs, we demonstrated the power of NGS to achieve a molecular etiology, expanding the mutational spectrum and proposing accurate genetic counseling in this group of heterogeneous diseases without therapeutic options.
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The International Union of Pure and Applied Chemistry (IUPAC) has a long tradition of supporting the compilation of chemical data and their evaluation through direct projects, nomenclature and terminology work, and partnerships with international scientific bodies, government agencies and other organizations. The IUPAC Interdivisional Subcommittee on Critical Evaluation of Data (ISCED) has been established to provide guidance on issues related to the evaluation of chemical data. In this first report we define the general principles of the evaluation of scientific data and describe best practices and approaches to data evaluation in chemistry.
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The São Domingos mine is within the Iberian Pyrite Belt, a mining district with large concentrations of polymetallic massive sulfide deposits. Mine waste heaps are considered extreme environments, since they contain high total concentrations of potentially hazardous elements (PHE), which contribute to inhibiting the development of most plants. Autochthonous plant species, such as Cistus salviifolius L., are able to grow naturally in this degraded environment, and may contribute to minimizing the negative chemical impacts and improving the landscape quality. However, the environmental rehabilitation processes associated with the development of these plants (phytostabilization) are very slow, so the use of materials/wastes to improve some physicochemical properties of the matrix is necessary in order to speed up the process. This work studied the effectiveness of the phytostabilization with C. salviifolius of gossan mine wastes from the mine of São Domingos amended with organic and inorganic wastes in order to construct Technosols. The mine wastes have an acid pH (≈3.5), high total concentrations of PHE and low concentrations of organic C and available nutrients. The best vegetative development occurred without visible signs of toxicity in the Technosols containing a mixture of agriculture residues. These treatments allowed the improvement of the soil-plant system providing a better plant cover and improved several chemical properties of mine wastes, helping to speed up the environmental rehabilitation.
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Humanos , Masculino , Adulto , Receptor 1 de Folato , Ácido Fólico , Distrofias Neuroaxonais , ParaplegiaRESUMO
BACKGROUND: Maspin (SERPINB5) is a potential tumor suppressor gene with pleiotropic biological activities, including regulation of cell proliferation, death, adhesion, migration and gene expression. Several studies indicate that nuclear localization is essential for maspin tumor suppression activity. We have previously shown that the EGFR activation leads to maspin nuclear localization in MCF-10A cells. The present study investigated which EGFR downstream signaling molecules are involved in maspin nuclear localization and explored a possible role of cell-cell contact in this process. METHODS: MCF-10A cells were treated with pharmacological inhibitors against EGFR downstream pathways followed by EGF treatment. Maspin subcellular localization was determined by immunofluorescence. Proteomic and interactome analyses were conducted to identify maspin-binding proteins in EGF-treated cells only. To investigate the role of cell-cell contact these cells were either treated with chelating agents or plated on different cell densities. Maspin and E-cadherin subcellular localization was determined by immunofluorescence. RESULTS: We found that PI3K-Akt and JAK2-STAT3, but not MAP kinase pathway, regulate EGF-induced maspin nuclear accumulation in MCF-10A cells. We observed that maspin is predominantly nuclear in sparse cell culture, but it is redistributed to the cytoplasm in confluent cells even in the presence of EGF. Proteomic and interactome results suggest a role of maspin on post-transcriptional and translation regulation, protein folding and cell-cell adhesion. CONCLUSIONS: Maspin nuclear accumulation is determined by an interplay between EGFR (via PI3K-Akt and JAK2-STAT3 pathways) and cell-cell contact. Video Abstract.
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Comunicação Celular/genética , Janus Quinase 2/genética , Fator de Transcrição STAT3/genética , Serpinas/genética , Linhagem Celular Tumoral , Núcleo Celular/genética , Núcleo Celular/ultraestrutura , Proliferação de Células/genética , Fator de Crescimento Epidérmico/genética , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Proteínas Quinases Ativadas por Mitógeno/genética , Fosfatidilinositol 3-Quinases/genética , Proteômica , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais/genéticaRESUMO
BACKGROUND: Here we describe a new class of cryptides (peptides encrypted within a larger protein) with antimicrobial properties, named schistocins, derived from SmKI-1, a key protein in Shistosoma mansoni survival. This is a multi-functional protein with biotechnological potential usage as a therapeutic molecule in inflammatory diseases and to control schistosomiasis. METHODS: We used our algorithm enCrypted, to perform an in silico proteolysis of SmKI-1 and a screening for potential antimicrobial activity. The selected peptides were chemically synthesized, tested in vitro and evaluated by both structural (CD, NMR) and biophysical (ITC) studies to access their structure-function relationship. RESULTS: EnCrypted was capable of predicting AMPs in SmKI-1. Our biophysical analyses described a membrane-induced conformational change from random coil-to-α-helix and a peptide-membrane equilibrium for all schistocins. Our structural data allowed us to suggest a well-known mode of peptide-membrane interaction in which electrostatic attraction between the cationic peptides and anionic membranes results in the bilayer disordering. Moreover, the NMR H/D exchange data with the higher entropic contribution observed for the peptide-membrane interaction showed that schistocins have different orientations upon the membrane. CONCLUSIONS: This work demonstrate the robustness for using the physicochemical features of predicted peptides in the identification of new bioactive cryptides. Besides, it demonstrates the relevance of combining these analyses with biophysical methods to understand the peptide-membrane affinity and improve further algorithms. GENERAL SIGNIFICANCE: Bioprospecting cryptides can be conducted through data mining of protein databases demonstrating the success of our strategy. The peptides-based agents derived from SmKI-1 might have high impact for system-biology and biotechnology.
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Antibacterianos/farmacologia , Antifúngicos/farmacologia , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Schistosoma mansoni/química , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Candida/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Proteínas Citotóxicas Formadoras de Poros/síntese química , Proteínas Citotóxicas Formadoras de Poros/química , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacosRESUMO
Dyslipidemia is a main driver of cardiovascular diseases. The ability of macrophages to scavenge excess lipids implicate them as mediators in this process and understanding the mechanisms underlying macrophage lipid metabolism is key to the development of new treatments. Here, we investigated how adipose tissue macrophages regulate post-prandial cholesterol transport. Single-cell RNA sequencing and protected bone marrow chimeras demonstrated that ingestion of lipids led to specific transcriptional activation of a population of resident macrophages expressing Lyve1, Tim4, and ABCA1. Blocking the phosphatidylserine receptor Tim4 inhibited lysosomal activation and the release of post-prandial high density lipoprotein cholesterol following a high fat meal. Both effects were recapitulated by chloroquine, an inhibitor of lysosomal function. Moreover, clodronate-mediated cell-depletion implicated Tim4+ resident adipose tissue macrophages in this process. Thus, these data indicate that Tim4 is a key regulator of post-prandial cholesterol transport and adipose tissue macrophage function and may represent a novel pathway to treat dyslipidemia.
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Transportador 1 de Cassete de Ligação de ATP/metabolismo , Tecido Adiposo/metabolismo , Colesterol/metabolismo , Macrófagos/metabolismo , Proteínas de Membrana/metabolismo , Período Pós-Prandial/fisiologia , Tecido Adiposo/citologia , Animais , HDL-Colesterol/metabolismo , Dieta Hiperlipídica , Metabolismo dos Lipídeos , Lisossomos/metabolismo , Macrófagos/citologia , Camundongos , Obesidade/metabolismo , Obesidade/patologia , Ativação Transcricional , Proteínas de Transporte Vesicular/metabolismoAssuntos
Asma/diagnóstico , Aplicativos Móveis/normas , Rinite Alérgica/diagnóstico , Inquéritos e Questionários/normas , Adolescente , Telefone Celular , Feminino , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Medidas de Resultados Relatados pelo Paciente , Telemedicina , Adulto JovemRESUMO
PURPOSE: It is postulated that patients with different types of pituitary neuroendocrine tumors (PitNETs) may present a higher incidence of cancer. Factors underlying individuals becoming overweight, such as insulin resistance, hyperleptinemia, and low-grade inflammation, may play a role in the risk of differentiated thyroid carcinoma (DTC) in such patients. This study aimed to investigate the frequency of and obesity-related risk factors associated with DTC in patients with PitNETs. METHODS: This cross-sectional study involved 149 patients with nonacromegalic PitNETs (AG group), 71 patients with acromegaly (ACRO group), and 156 controls (CG group). All participants underwent insulin and blood glucose measurements with the determination of the homeostatic model assessment-insulin resistance (HOMA-IR) index, leptin, and high-sensitivity C-reactive protein (hsCRP), and they also underwent thyroid ultrasound. Clinically significant nodules were biopsied for subsequent cytopathological evaluation, and participants were operated on when indicated. RESULTS: Patients in the AG group had high levels of insulin resistance and significantly higher levels of leptin and hsCRP compared with those of patients in the ACRO group. There were no cases of DTC in the AG group; two findings, one incidental, of DTC occurred in the CG group, and three cases of DTC were present in the ACRO group. Acromegaly was associated with DTC after adjusted analysis. CONCLUSIONS: Our findings in patients with nonacromegalic PitNETs do not indicate a high risk for DTC despite the presence of metabolic and inflammatory risk factors for neoplastic events. In contrast, acromegaly promotes a greater risk of DTC.
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Adenocarcinoma/etiologia , Fatores de Risco Cardiometabólico , Inflamação/complicações , Tumores Neuroendócrinos/complicações , Neoplasias Hipofisárias/complicações , Neoplasias da Glândula Tireoide/etiologia , Acromegalia/complicações , Acromegalia/epidemiologia , Acromegalia/metabolismo , Adenocarcinoma/epidemiologia , Adenocarcinoma/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia/metabolismo , Brasil/epidemiologia , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Incidência , Inflamação/epidemiologia , Inflamação/metabolismo , Insulina/metabolismo , Resistência à Insulina/fisiologia , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/epidemiologia , Tumores Neuroendócrinos/metabolismo , Neoplasias Hipofisárias/epidemiologia , Neoplasias Hipofisárias/metabolismo , Fatores de Risco , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/metabolismo , Adulto JovemRESUMO
Background Maspin (SERPINB5) is a potential tumor suppressor gene with pleiotropic biological activities, including regulation of cell proliferation, death, adhesion, migration and gene expression. Several studies indicate that nuclear localization is essential for maspin tumor suppression activity. We have previously shown that the EGFR activation leads to maspin nuclear localization in MCF-10A cells. The present study investigated which EGFR downstream signaling molecules are involved in maspin nuclear localization and explored a possible role of cell–cell contact in this process. Methods MCF-10A cells were treated with pharmacological inhibitors against EGFR downstream pathways followed by EGF treatment. Maspin subcellular localization was determined by immunofluorescence. Proteomic and interactome analyses were conducted to identify maspin-binding proteins in EGF-treated cells only. To investigate the role of cell–cell contact these cells were either treated with chelating agents or plated on different cell densities. Maspin and E-cadherin subcellular localization was determined by immunofluorescence. Results We found that PI3K-Akt and JAK2-STAT3, but not MAP kinase pathway, regulate EGF-induced maspin nuclear accumulation in MCF-10A cells. We observed that maspin is predominantly nuclear in sparse cell culture, but it is redistributed to the cytoplasm in confluent cells even in the presence of EGF. Proteomic and interactome results suggest a role of maspin on post-transcriptional and translation regulation, protein folding and cell–cell adhesion. Conclusions Maspin nuclear accumulation is determined by an interplay between EGFR (via PI3K-Akt and JAK2-STAT3 pathways) and cell–cell contact.
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Betacoronavirus , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Brasil/epidemiologia , COVID-19 , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/terapia , Humanos , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/terapia , SARS-CoV-2 , Tuberculose/terapiaRESUMO
Reproduction of Trachurus picturatus off the western Portuguese coast was studied over 1 yr. During histological analyses, the presence of Kudoa sp. was detected in advanced vitellogenic oocytes. Kudoa infections are known to cause economic loss through the induction of post-mortem liquefaction of fish muscles, but ovarian infection as reported in this study will seriously affect the reproductive potential of the species and thus impact fisheries productivity. Only females showed gonad infection which led to total degradation of advanced vitellogenic oocytes. No macroscopic, somatic or condition indices revealed differences between infected and uninfected females, rendering this infection event a concealed suppression of reproduction.
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Doenças dos Peixes , Infecções/veterinária , Myxozoa , Perciformes , Animais , Feminino , Ovário , Doenças Parasitárias em AnimaisRESUMO
BACKGROUND AND PURPOSE: Acquired hepatocerebral degeneration (AHD) and hepatic encephalopathy (HE) are neurological complications of chronic liver disease (CLD) with portosystemic shunt. While HE is common, AHD is a rare entity, and the clinical imaging relationships observed in small series lack validation in large patient cohorts. The aim of this study was to characterize a cohort of AHD patients and to explore possible associations with HE coexistence. METHODS: We performed a retrospective analysis of patients with a working AHD diagnosis, between 2008 and 2019. Clinical, laboratory, imaging and neuropsychological results at first neurological observation were reviewed and compared between the 'AHD' group and the 'AHD with HE' group. RESULTS: A total of 76 patients were recruited. The most frequent neurological manifestations were neuropsychiatric (93.4%) and extrapyramidal (84.2%). Only 38% of patients had hypermanganesemia. Compared with the AHD group, the AHD with HE group had more hyperkinetic movement disorders (71.4% vs. 38.5%; P = 0.05), a higher number of patients on the dementia spectrum (57.7% vs. 20%; P = 0.04), higher median ammonia levels (P = 0.014) and more widespread cortico-subcortical and pyramidal involvement on brain magnetic resonance imaging. Nineteen patients underwent liver transplantation, with significantly improved survival (P = 0.006). DISCUSSION: Hepatic encephalopathy and AHD often coexist in the same patient. Seventy-six patients with CLD and AHD were evaluated, making this one of the largest reported AHD cohorts. Blood manganese level was a weak diagnostic marker in AHD. Early liver function restoration through liver transplantation improved survival. Our report provides a detailed description of the phenotype and long-term outcome of AHD, with relevance for diagnosis and treatment.
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Encefalopatia Hepática , Encefalopatia Hepática/epidemiologia , Encefalopatia Hepática/etiologia , Degeneração Hepatolenticular/complicações , Degeneração Hepatolenticular/epidemiologia , Humanos , Cirrose Hepática , Transplante de Fígado , Estudos RetrospectivosRESUMO
Current paleontological techniques to separate vertebrate fossils from encasing iron-rich cements by chemical means are limited by the low solubility of common iron(III) hydroxide oxides such as hematite and goethite. This study examines novel geochemical extractions capable of selectively dissolving iron(III) hydroxide oxides, in aqueous solutions of pH 9-11, without damaging fossilised bones or teeth (hydroxidecarbonate-apatite). This involves the siderophore ligands pyridoxal isonicotinoyl hydrazone (PIH), salicylaldehyde isonicotinoyl hydrazone (SIH), and acetohydroxamic acid (aHA), whose coordination complexes with iron(III) show exceptionally high formation stability constants. The methods have been tested on natural hematite and fossil containing samples from the Riversleigh World Heritage Area in Australia. Both 0.01â mol dm-3 aHA and 0.001â mol dm-3 PIH at pHâ 9.7 were able to dissolve over 0.1â mmol dm-3 of the goethite coating bone fragments.