Purpose
To study the effects of dexamethasone sodium phosphate (Dex) on human trabecular meshwork (HTM) cells in vitro.
Methods
HTM cells were treated with Dex 2 mg/ml, 1 mg/ml, 0.5 mg/ml, ...0.25 mg/ml, 0.1 mg/ml, or 0.05 mg/ml for 24 h. Cell viability was measured by a trypan blue exclusion test. Caspase-3/7, -8, -9 and -12 activities were measured by fluorochrome assays as mean signal intensity (msi) to assess apoptosis. Mitochondrial dehydrogenase activity was determined by a WST assay to quantify mitochondrial damage.
Results
Mean cell viabilities of HTM cells exposed to Dex at the higher doses of 2 mg/ml, 1 mg/ml, and 0.5 mg/ml were reduced: 11.9 % ± 3.5 (
P
< 0.001), 31.2 % ± 3.2 (
P
< 0.001), and 76.6 % ± 4.4 (
P
< 0.01). At the lower doses of 0.25 mg/ml, 0.1 mg/ml or 0.05 mg/ml, no significant cell viability reductions were seen: 96.3 % ± 0.7 (
P
> 0.05), 95.3 % ± 2.5 (
P
> 0.05) and 93.8 % ± 2.3 (
P
> 0.05), respectively compared to untreated HTM cells (97.0 % ± 1.9). Caspase-3/7 activity (msi) of HTM cells exposed to Dex 2, 1 or 0.5 mg/ml was 21068 ± 2498 (
P
< 0.001), 26994 ± 3104 (
P
< 0.001) and 20416 ± 1150 (
P
< 0.001) compared to untreated HTM cells 1148 ± 803. Caspase-9 activity (msi) of HTM cells after exposure to Dex 2, 1 or 0.5 mg/ml was 14188 ± 1203 (
P
< 0.001), 13256 ± 1564 (
P
< 0.001) and 15041 ± 1584 (
P
< 0.001) compared to untreated HTM cells 1748 ± 524. The lower doses of Dex did not significantly increase caspase-3/7 or -9 activities. There were no increases for caspase-8 or -12 activities at any of the tested Dex doses. The WST assay showed mitochondrial dehydrogenase activities of 14.3 ± 0.7 (
P
< 0.001), 9.6 ± 0.3 (
P
< 0.001) and 56.0 ± 7.6 (
P
< 0.001) at 2 mg/ml, 1 mg/ml and 0.5 mg/ml Dex compared to untreated HTM cells (186.1 ± 15.0).
Conclusions
Dex at 0.25, 0.1 and 0.05 mg/ml clinical dose did not cause significant reduction in cell viability, increased apoptosis, or mitochondrial dysfunction of HTM cells in vitro. At high doses (2, 1 or 0.5 mg/ml) Dex caused apoptosis via mitochondrial pathways.
Abstract
Background
Neurofibromatosis type 2 (NF2) is a genetic tumor-predisposition disorder caused by NF2/merlin tumor suppressor gene inactivation. The hallmark of NF2 is formation of bilateral ...vestibular schwannomas (VS). Because merlin modulates activity of the Ras/Raf/mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway, we investigated repurposing drugs targeting MEK1 and/or MEK2 as a treatment for NF2-associated schwannomas.
Methods
Mouse and human merlin-deficient Schwann cell lines (MD-MSC/HSC) were screened against 6 MEK1/2 inhibitors. Efficacious drugs were tested in orthotopic allograft and NF2 transgenic mouse models. Pathway and proteome analyses were conducted. Drug efficacy was examined in primary human VS cells with NF2 mutations and correlated with DNA methylation patterns.
Results
Trametinib, PD0325901, and cobimetinib were most effective in reducing MD-MSC/HSC viability. Each decreased phosphorylated pERK1/2 and cyclin D1, increased p27, and induced caspase-3 cleavage in MD-MSCs. Proteomic analysis confirmed cell cycle arrest and activation of pro-apoptotic pathways in trametinib-treated MD-MSCs. The 3 inhibitors slowed allograft growth; however, decreased pERK1/2, cyclin D1, and Ki-67 levels were observed only in PD0325901 and cobimetinib-treated grafts. Tumor burden and average tumor size were reduced in trametinib-treated NF2 transgenic mice; however, tumors did not exhibit reduced pERK1/2 levels. Trametinib and PD0325901 modestly reduced viability of several primary human VS cell cultures with NF2 mutations. DNA methylation analysis of PD0325901-resistant versus -susceptible VS identified genes that could contribute to drug resistance.
Conclusion
MEK inhibitors exhibited differences in antitumor efficacy resistance in schwannoma models with possible emergence of trametinib resistance. The results support further investigation of MEK inhibitors in combination with other targeted drugs for NF2 schwannomas.
Display omitted
•Brazil is the world’s third largest banana producer.•Green bananas contain substantial starch content which can be extracted for industrial utilization, avoiding waste in their ...production cycle.•The understanding of starch properties of green bananas is essential for the industrial application.•The banana is presented as a potential source of native starches with special properties.
The starch market is constantly evolving and studies that provide information about the physical and rheological properties of native starches to meet the diverse demands of the sector are increasingly necessary. In this study starches obtained from five cultivars of banana were analyzed for size and shape of granules, crystallinity, chemical composition, resistant starch, swelling power, solubility, thermal and paste properties. The granules of starch were large (36.58–47.24μm), oval, showed crystallinity pattern type B and the index of crystallinity ranged from 31.94 to 34.06%. The phosphorus content ranged from 0.003 to 0.011%, the amylose ranged from 25.13 to 29.01% and the resistant starch ranged from 65.70 to 80.28%. The starches showed high peak viscosity and breakdown, especially those obtained from ‘Nanicão’ and ‘Grand Naine’. Peak temperature of gelatinization was around 71°C, the enthalpy change (ΔH) ranged from 9.45 to 14.73Jg−1. The starch from ‘Grand Naine’ showed higher swelling power (15.19gg−1) and the starch from ‘Prata-Anã’ higher solubility (11.61%). The starches studied are highlighted by their physical and chemical characteristics and may be used in several applications.
•Study of strategies to improve SCC eco-efficiency performance.•Review of SCC dosing methods.•Review of waste incorporation in SCCs.•Use of the desirability statistical function for eco-efficiency ...analysis.•Eco-efficiency comparison of SCCs containing waste.
This review article assesses the origin and mitigation routes for the environmental impacts of self-compacting concretes (SCC), analyzing existing dosing methodologies and comparing the incorporation of different residues. SCC is one of the most harmful concrete mixtures to the environment due to the higher contents of cement and chemical admixtures. Comparing the eco-efficiency of SCC based on mechanical performance showed that small changes in materials can modify the fluidity and strength and, consequently, the eco-efficiency of the mixture. Thus, incorporating residues can increase the eco-efficiency of SCCs since an efficient dosing methodology is used.
The digital era has perpetuated new pedagogies of collective participation in networks that requires reflection in the conventional education area, because of YouTube, as audiovisual platform of ...outstanding international recognition, concentrates an extensive repertoire of informal learning practices among young people. In this case, the research focuses on a form of literary expression driven by the new Booktube community, which is dedicated to the recommendation of books and the promotion of reading by focusing their messages through the videoblog format. This aspect, closely popularized in the platform, allow us to deepen new youth practices outside classroom that refer to the promotion of books and critical and judicious expression on aspects related to content, formats, genres and authors in a context supported by the media ecology. In order to deepen the reasons why youth reads currently, we developed a literature review starting with the transmedia literacy concept evaluating narrative and aesthetic competences and applying a content analysis and a case study that collects channels of two Spanish booktubers with high impact and community: Javier Ruescas and Fly like a Butterfly. Results discern an affinity space linked to the opinion of peers that promotes reading and writing, and the ability to interpret, describe, compare and reflect about the literary context.
In a previous scientific opinion on application EFSA‐GMO‐BE‐2016‐138, the EFSA Panel on Genetically Modified Organisms (GMO Panel) could not conclude on the comparative analysis and on the food/feed ...safety assessment of genetically modified (GM) oilseed rape (OSR) MS11 because of the lack of an appropriate compositional data set. Following a request from the European Commission, the GMO Panel assessed additional information related to OSR MS11 to complement the original scientific opinion. The GMO Panel concluded that the information submitted (on the composition of the two‐event stack MS11 × RF3) could not be used for the assessment of the composition of OSR MS11 and requested the applicant to perform a complementary set of field trials to generate additional data. The applicant did not perform the requested field trials and did not provide any new experimental data on the composition of OSR MS11. Hence, the GMO Panel is still not in the position to conclude on either the compositional analysis or the toxicological, allergenicity or nutritional assessment of OSR MS11. Therefore, the previous conclusions of the GMO Panel still hold.
Two commercial varieties of Peruvian carrot ('Amarela de Carandaí' and 'Senador Amaral') were processed into flour, starch and bagasse and chemically evaluated. The starch was extracted, modified ...with H2O2 and characterized by the physicochemical methods. By using the methylene blue dyeing, the granules of the modified starches showed intense blue color. The carboxyl content, the reducing power and the amount of the water liberated from the pastes after the freeze-thawing were higher for the oxidized starches and their pastes were clearer than those of the native starches of the two varieties from the two production areas. The RVA viscoamylography showed that the modified starches had lower viscosities with differences between the varieties. In the thermal analysis, the temperatures of the pyrolysis were higher for the native (310.37, 299.08, 311.18 ºC) than for the modified starches (294.16, 296.65 e 293.29 ºC) for both the varieties. This difference could be related with the larger surface of the granules due to the partial degradation promoted by the chemical modification. In almost all results, the differences were evident between the varieties but not for the cultivation places.
No presente trabalho duas variedades comerciais de mandioquinha-salsa ('Amarela de Carandaí' e 'Senador Amaral') obtidas dos municípios de Castro e de Piraí do Sul (Paraná) foram processadas para a obtenção de farinha, farelo e amido e essas três frações foram caracterizadas quimicamente. O amido foi extraído, modificado com H2O2 e caracterizado por meio de análises físico-químicas. Na coloração com azul de metileno os grânulos dos amidos oxidados apresentaram coloração azul mais intensa. O teor de carboxilas, o poder redutor e a quantidade de água liberada das pastas foram maiores para as amostras de amidos modificados. As pastas dos amidos modificados foram mais claras que as dos nativos. Na análise viscoamilográfica (RVA) os amidos modificados apresentaram as menores viscosidades e houve diferenças entre as variedades, sendo que o amido modificado da variedade Senador Amaral de Piraí do Sul apresentou os menores valores de pico de viscosidade. Na análise térmica, as temperaturas de pirólise foram mais altas para os amidos nativos das variedades da mandioquinha-salsa (310,37, 299,08, 311,18 ºC) do que para os amidos modificados (294,16, 296,65 e 293,29 ºC) e esta diferença pode estar relacionada a maior superfície dos grânulos de amido parcialmente degradados pela modificação oxidativa. Os resultados revelaram diferenças entre os amidos das duas variedades, mas não entre os locais de cultivo.
The authors discuss in this paper the role of inflammatory, anti-inflammatory, and regulatory cytokines in patients infected with different species of Leishmania in Amazonas State, Brazil. A ...comparative analysis was made of serum concentrations of these cytokines in the peripheral blood of 33 patients infected with cutaneous leishmaniasis. The isolates were identified as Leishmania guyanensis, L. naiffi, and L. amazonensis. Most (64%) of the patients were male ranging in age from 18 to 58 years. Protein expression profiles of IL-2, IL-4, IL-6, IL-10, IFN-γ, TNF-α, and IL-17 cytokines were shown to vary significantly between infected and noninfected (control group) individuals and according to the Leishmania species. Infection caused by L. guyanensis accounted for 73% of the cases and patients with this parasite also showed higher concentrations of IL-2, IFN-γ, IL-4, and IL-17 when compared to infection by L. amazonensis. Patients with infection caused by L. naiffi showed higher concentration of the cytokines analyzed when compared to uninfected patients; however, there was no statistically significant difference with the other species analyzed.
Absent in melanoma 2 (AIM2) is a sensor of cytosolic dsDNA and is responsible for the activation of inflammatory and host immune responses to DNA viruses and intracellular bacteria. AIM2 is a member ...of the hematopoietic interferon-inducible nuclear proteins with a 200 amino-acid repeat (HIN200) family, containing a pyrin domain (PYD) at the N-terminus. Several studies have demonstrated that AIM2 is responsible for host defense against intracellular bacteria such as Francisella tularensis, Listeria monocytogenes and Mycobacerium tuberculosis. However, the role of AIM2 in host defenses against Brucella is poorly understood. In this study, we have shown that AIM2 senses Brucella DNA in dendritic cells to induce pyroptosis and regulates type I IFN. Confocal microscopy of infected cells revealed co-localization between Brucella DNA and endogenous AIM2. Dendritic cells from AIM2 KO mice infected with B. abortus showed impaired secretion of IL-1β as well as compromised caspase-1 cleavage. AIM2 KO mice displayed increased susceptibility to B. abortus infection in comparison to wild-type mice, and this susceptibility was associated with defective IL-1β production together with reduced IFN-γ responses. In summary, the increased bacterial burden observed in vivo in AIM2 KO animals confirmed that AIM2 is essential for an effective innate immune response against Brucella infection.
A didática constituirá sempre um campo instável em que se procura um equilíbrio entre os vértices do triângulo clássico: o professor – o(s) aluno (s) que aprende(m) – a matéria ou disciplina a ...ensinar /aprender. Os tempos atuais são marcados por desafios enormes colocados à didática, em que avulta o trânsito massivo do ensino presencial para o ensino online, por imposição da pandemia COVID 19. Mas questionamentos mais antigos persistem, também eles merecedores de resposta. O objetivo central do presente artigo é o de examinar criticamente as implicações didáticas de dois documentos que, em Portugal, orientam os processos de ensino – aprendizagem na educação básica e no ensino secundário: o Perfil do Aluno à saída da escolaridade obrigatória de 12 anos e as Aprendizagens Essenciais a realizar ao longo desse período. O Projeto de Autonomia e Flexibilidade Curricular, em desenvolvimento desde 2017, consagra os princípios orientadores da ação das escolas, dos professores e dos alunos para a consecução do referido perfil e das aprendizagens a ele associadas. Adotando uma perspetiva crítica sobre o campo da didática, pretende-se mapear aquelas variáveis de contexto que mais poderão contribuir para o sucesso / insucesso do projeto. Os dados obtidos são interpretados com contributos da investigação em didática, da teoria curricular, da sociologia, da psicologia da aprendizagem, bem como do conhecimento científico sobre formação de professores. A metodologia utilizada é a da análise documental e a da análise de conteúdo. O resultado é um ensaio que poderá propiciar a reflexão acerca da inovação didática.
PDF
