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1.
Sci Rep ; 14(1): 3108, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326394

RESUMO

TRUEFAD (TRUE Fiber Atrophy Distinction) is a bioimagery user-friendly tool developed to allow consistent and automatic measurement of myotube diameter in vitro, muscle fiber size and type using rodents and human muscle biopsies. This TRUEFAD package was set up to standardize and dynamize muscle research via easy-to-obtain images run on an open-source plugin for FIJI. We showed here both the robustness and the performance of our pipelines to correctly segment muscle cells and fibers. We evaluated our pipeline on real experiment image sets and showed consistent reliability across images and conditions. TRUEFAD development makes possible systematical and rapid screening of substances impacting muscle morphology for helping scientists focus on their hypothesis rather than image analysis.


Assuntos
Fibras Musculares Esqueléticas , Software , Humanos , Reprodutibilidade dos Testes , Fibras Musculares Esqueléticas/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Técnicas de Cultura de Células
2.
Nutrients ; 15(17)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37686798

RESUMO

Aging is associated with a decline in muscle mass and function, leading to increased risk for mobility limitations and frailty. Dietary interventions incorporating specific nutrients, such as pea proteins or inulin, have shown promise in attenuating age-related muscle loss. This study aimed to investigate the effect of pea proteins given with inulin on skeletal muscle in old rats. Old male rats (20 months old) were randomly assigned to one of two diet groups for 16 weeks: a 'PEA' group receiving a pea-protein-based diet, or a 'PEA + INU' group receiving the same pea protein-based diet supplemented with inulin. Both groups showed significant postprandial stimulation of muscle p70 S6 kinase phosphorylation rate after consumption of pea proteins. However, the PEA + INU rats showed significant preservation of muscle mass with time together with decreased MuRF1 transcript levels. In addition, inulin specifically increased PGC1-α expression and key mitochondrial enzyme activities in the plantaris muscle of the old rats. These findings suggest that dietary supplementation with pea proteins in combination with inulin has the potential to attenuate age-related muscle loss. Further research is warranted to explore the underlying mechanisms and determine the optimal dosage and duration of intervention for potential translation to human studies.


Assuntos
Proteínas de Ervilha , Humanos , Masculino , Animais , Ratos , Lactente , Inulina/farmacologia , Músculo Esquelético , Suplementos Nutricionais , Envelhecimento
3.
Waste Manag ; 170: 103-111, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37562200

RESUMO

The pozzolanic reaction of fly ashes with calcium-based additives can be effectively used to solidify and chemically stabilize (S&S process) highly concentrated brines inside a cementitious matrix. However, complex interactions between the fly ash, the additive, and the brine typically affect the phases formed at equilibrium, and the resulting solid capacity to successfully encapsulate the brine and its contaminants. Here, the performances of two types of fly ash (a Class C and Class F fly ash) are assessed when combined with different additives (two types of cement, or lime with and without NaAlO2), and two types of brine (NaCl or CaCl2) over a range of concentrations (0 ≤ [Cl-] ≤ 2 M). The best performing matrices - i.e., the matrices with the highest Cl-containing phases content - were identified using XRD and TGA. The experimental results were then combined with thermodynamic modeling to dissociate the contribution of the fly ash from that of the additives. All results were implemented in a machine learning model that showed good accuracy at predicting the fly ash degree of reaction, allowing for the robust prediction of extended systems performance when combined with thermodynamic modeling.


Assuntos
Cinza de Carvão , Eliminação de Resíduos , Eliminação de Resíduos/métodos , Cálcio , Cloreto de Sódio , Cloreto de Cálcio
4.
Sci Rep ; 13(1): 8773, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37253964

RESUMO

Microsporidia are obligate intracellular parasites able to infect a wide range of hosts from invertebrates to vertebrates. The success of their invasion process is based on an original organelle, the polar tube, which is suddenly extruded from the spore to inoculate the sporoplasm into the host cytoplasm. The polar tube is mainly composed of proteins named polar tube proteins (PTPs). A comparative analysis allowed us to identify genes coding for 5 PTPs (PTP1 to PTP5) in the genome of the microsporidian Anncaliia algerae. While PTP1 and PTP2 are found on the whole polar tube, PTP3 is present in a large part of the extruded polar tube except at its end-terminal part. On the contrary, PTP4 is specifically detected at the end-terminal part of the polar tube. To complete PTPs repertoire, sequential sporal protein extractions were done with high concentration of reducing agents. In addition, a method to purify polar tubes was developed. Mass spectrometry analysis conducted on both samples led to the identification of a PTP3-like protein (PTP3b), and a new PTP (PTP7) only found at the extremity of the polar tube. The specific localization of PTPs asks the question of their roles in cell invasion processes used by A. algerae.


Assuntos
Proteínas Fúngicas , Microsporídios , Animais , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Microsporídios/genética , Microsporídios/metabolismo , Citoplasma/metabolismo , Organelas/metabolismo
5.
Exp Psychol ; 69(5): 275-283, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36655887

RESUMO

When participants read a text for comprehension while identifying a target letter, the letter is more often missed in a frequent function word than in a less frequent content word. This is the missing-letter effect. Studies have shown the importance of both frequency and word function. The role of each of these factors in development is less understood. The goal of this study was to revisit the influence of frequency and word function in the missing-letter effect in development with better-controlled stimuli. Two hundred sixteen participants took part in this study and were divided into five groups (6-7 years, 8 years, 9 years, 10-11 years, and university students). They were asked to read four experimental texts for comprehension and to circle a target letter. The results showed a basic missing-letter effect with more omissions for a frequent function word than a less frequent content word for every group. When frequency was controlled, we found a word function effect as early as 6-7 years of age, with more omissions for a function word than a content word. In contrast, when word function was controlled, an effect of frequency was only significant for adults and 8-year-olds. These results clarify discrepancies in the literature and support the importance of rigorous stimuli control.


Assuntos
Leitura , Adulto , Humanos
6.
J Med Chem ; 63(13): 6774-6783, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32453569

RESUMO

We herein report the first thorough analysis of the structure-permeability relationship of semipeptidic macrocycles. In total, 47 macrocycles were synthesized using a hybrid solid-phase/solution strategy, and then their passive and cellular permeability was assessed using the parallel artificial membrane permeability assay (PAMPA) and Caco-2 assay, respectively. The results indicate that semipeptidic macrocycles generally possess high passive permeability based on the PAMPA, yet their cellular permeability is governed by efflux, as reported in the Caco-2 assay. Structural variations led to tractable structure-permeability and structure-efflux relationships, wherein the linker length, stereoinversion, N-methylation, and peptoids site-specifically impact the permeability and efflux. Extensive nuclear magnetic resonance, molecular dynamics, and ensemble-based three-dimensional polar surface area (3D-PSA) studies showed that ensemble-based 3D-PSA is a good predictor of passive permeability.


Assuntos
Compostos Macrocíclicos/química , Compostos Macrocíclicos/metabolismo , Peptídeos/química , Células CACO-2 , Humanos , Membranas Artificiais , Permeabilidade
7.
Int J Cancer ; 145(5): 1346-1357, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30807645

RESUMO

Aberrant activation in fibroblast growth factor signaling has been implicated in the development of various cancers, including squamous cell lung cancer, squamous cell head and neck carcinoma, colorectal and bladder cancer. Thus, fibroblast growth factor receptors (FGFRs) present promising targets for novel cancer therapeutics. Here, we evaluated the activity of a novel pan-FGFR inhibitor, rogaratinib, in biochemical, cellular and in vivo efficacy studies in a variety of preclinical cancer models. In vitro kinase activity assays demonstrate that rogaratinib potently and selectively inhibits the activity of FGFRs 1, 2, 3 and 4. In line with this, rogaratinib reduced proliferation in FGFR-addicted cancer cell lines of various cancer types including lung, breast, colon and bladder cancer. FGFR and ERK phosphorylation interruption by rogaratinib treatment in several FGFR-amplified cell lines suggests that the anti-proliferative effects are mediated by FGFR/ERK pathway inhibition. Furthermore, rogaratinib exhibited strong in vivo efficacy in several cell line- and patient-derived xenograft models characterized by FGFR overexpression. The observed efficacy of rogaratinib strongly correlated with FGFR mRNA expression levels. These promising results warrant further development of rogaratinib and clinical trials are currently ongoing (ClinicalTrials.gov Identifiers: NCT01976741, NCT03410693, NCT03473756).


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias/tratamento farmacológico , Piperazinas/farmacologia , Pirróis/farmacologia , Receptores de Fatores de Crescimento de Fibroblastos/antagonistas & inibidores , Tiofenos/farmacologia , Animais , Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/metabolismo , Fosforilação/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Nat Commun ; 9(1): 2169, 2018 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-29867088

RESUMO

Understanding the dissolution of silicate glasses and minerals from atomic to macroscopic levels is a challenge with major implications in geoscience and industry. One of the main uncertainties limiting the development of predictive models lies in the formation of an amorphous surface layer--called gel--that can in some circumstances control the reactivity of the buried interface. Here, we report experimental and simulation results deciphering the mechanisms by which the gel becomes passivating. The study conducted on a six-oxide borosilicate glass shows that gel reorganization involving high exchange rate of oxygen and low exchange rate of silicon is the key mechanism accounting for extremely low apparent water diffusivity (∼10-21 m2 s-1), which could be rate-limiting for the overall reaction. These findings could be used to improve kinetic models, and inspire the development of new molecular sieve materials with tailored properties as well as highly durable glass for application in extreme environments.

9.
Sci Rep ; 8(1): 3761, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29491348

RESUMO

The porous structure and mass transport characteristics of disordered silicate porous media were investigated via a geometry based analysis of water confined in the pores. Disordered silicate porous media were constructed to mimic the dissolution behavior of an alkali aluminoborosilicate glass, i.e., soluble Na and B were removed from the bulk glass, and then water molecules and Na were introduced into the pores to provide a complex porous structure filled with water. This modelling approach revealed large surface areas of disordered porous media. In addition, a number of isolated water molecules were observed in the pores, despite accessible porous connectivity. As the fraction of mobile water was approximately 1%, the main water dynamics corresponded to vibrational motion in a confined space. This significantly reduced water mobility was due to strong hydrogen-bonding water-surface interactions resulting from the large surface area. This original approach provides a method for predicting the porous structure and water transport characteristics of disordered silicate porous media.

10.
ChemMedChem ; 13(5): 437-445, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29451369

RESUMO

Rogaratinib (BAY 1163877) is a highly potent and selective small-molecule pan-fibroblast growth factor receptor (FGFR) inhibitor (FGFR1-4) for oral application currently being investigated in phase 1 clinical trials for the treatment of cancer. In this publication, we report its discovery by de novo structure-based design and medicinal chemistry optimization together with its pharmacokinetic profile.


Assuntos
Descoberta de Drogas , Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirróis/farmacologia , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Tiofenos/farmacologia , Humanos , Modelos Moleculares , Estrutura Molecular , Piperazinas/química , Inibidores de Proteínas Quinases/química , Pirróis/química , Bibliotecas de Moléculas Pequenas/química , Tiofenos/química
11.
Nutrients ; 6(12): 5500-16, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25470375

RESUMO

Although the management of malnutrition is a priority in older people, this population shows a resistance to refeeding. Fresh bee pollen contains nutritional substances of interest for malnourished people. The aim was to evaluate the effect of fresh bee pollen supplementation on refeeding efficiency in old malnourished rats. Male 22-month-old Wistar rats were undernourished by reducing food intake for 12 weeks. The animals were then renourished for three weeks with the same diet supplemented with 0%, 5% or 10% of fresh monofloral bee pollen. Due to changes in both lean mass and fat mass, body weight decreased during malnutrition and increased after refeeding with no between-group differences (p < 0.0001). Rats refed with the fresh bee pollen-enriched diets showed a significant increase in muscle mass compared to restricted rats (p < 0.05). The malnutrition period reduced the muscle protein synthesis rate and mTOR/p70S6kinase/4eBP1 activation, and only the 10%-pollen diet was able to restore these parameters. Mitochondrial activity was depressed with food restriction and was only improved by refeeding with the fresh bee pollen-containing diets. In conclusion, refeeding diets that contain fresh monofloral bee pollen improve muscle mass and metabolism in old, undernourished rats.


Assuntos
Abelhas , Suplementos Nutricionais , Metabolismo Energético , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Estado Nutricional , Pólen , Desnutrição Proteico-Calórica/dietoterapia , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Adiposidade , Fatores Etários , Animais , Proteínas de Transporte/metabolismo , Citocinas/sangue , Modelos Animais de Doenças , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Músculo Esquelético/fisiopatologia , Fosfoproteínas/metabolismo , Desnutrição Proteico-Calórica/sangue , Desnutrição Proteico-Calórica/enzimologia , Desnutrição Proteico-Calórica/fisiopatologia , Ratos Wistar , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Aumento de Peso
12.
Aging Cell ; 13(6): 1001-11, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25139155

RESUMO

Obesity and aging are characterized by decreased insulin sensitivity (IS) and muscle protein synthesis. Intramuscular ceramide accumulation has been implicated in insulin resistance during obesity. We aimed to measure IS, muscle ceramide level, protein synthesis, and activation of intracellular signaling pathways involved in translation initiation in male Wistar young (YR, 6-month) and old (OR, 25-month) rats receiving a low- (LFD) or a high-fat diet (HFD) for 10 weeks. A corresponding cellular approach using C2C12 myotubes treated with palmitate to induce intracellular ceramide deposition was taken. A decreased ability of adipose tissue to store lipids together with a reduced adipocyte diameter and a development of fibrosis were observed in OR after the HFD. Consequently, OR fed the HFD were insulin resistant, showed a strong increase in intramuscular ceramide level and a decrease in muscle protein synthesis associated with increased eIF2α phosphorylation. The accumulation of intramuscular lipids placed a lipid burden on mitochondria and created a disconnect between metabolic and regulating pathways in skeletal muscles of OR. In C2C12 cells, palmitate-induced ceramide accumulation was associated with a decreased protein synthesis together with upregulated eIF2α phosphorylation. In conclusion, a reduced ability to expand adipose tissues was found in OR, reflecting a lower lipid buffering capacity. Muscle mitochondrial activity was affected in OR conferring a reduced ability to oxidize fatty acids entering the muscle cell. Hence, OR were more prone to ectopic muscle lipid accumulation than YR, leading to decreased muscle protein anabolism. This metabolic change is a potential therapeutic target to counter sarcopenic obesity.


Assuntos
Tecido Adiposo/metabolismo , Fator de Iniciação 2 em Eucariotos/metabolismo , Resistência à Insulina/fisiologia , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Sarcopenia/metabolismo , Envelhecimento/metabolismo , Animais , Ceramidas , Dieta Hiperlipídica , Modelos Animais de Doenças , Masculino , Ratos , Ratos Wistar , Transdução de Sinais , eIF-2 Quinase
16.
Biotechnol J ; 2(2): 221-31, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17219461

RESUMO

3-Acyloxyl-2-oxopropyl ethers of umbelliferone were investigated as new fluorogenic substrates for lipases and esterases. The aliphatic primary alcohol-leaving group released the fluorescent product umbelliferone by an enolization/beta-elimination reaction similar to the triose phosphate isomerase (TIM) reaction. A similarly designed phenylacetamide provided a fluorescent probe for penicillin G acylase, whereby the enolization/beta-elimination sequence from the intermediate aminoketone was very fast and spontaneous even under acidic conditions. The corresponding epoxyketone was not fluorogenic with epoxide hydrolases (EH). These substrates represent periodate-free Clips-otrade mark substrates.


Assuntos
Esterases/metabolismo , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Lipase/metabolismo , Penicilina Amidase/metabolismo , Acetamidas/química , Acetamidas/metabolismo , Epóxido Hidrolases/metabolismo , Hidrólise , Espectroscopia de Ressonância Magnética , Modelos Químicos , Estrutura Molecular , Espectrometria de Fluorescência , Especificidade por Substrato , Umbeliferonas/química , Umbeliferonas/metabolismo
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