Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
PLoS One ; 19(4): e0302394, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38669233

RESUMO

Digital speech recognition is a challenging problem that requires the ability to learn complex signal characteristics such as frequency, pitch, intensity, timbre, and melody, which traditional methods often face issues in recognizing. This article introduces three solutions based on convolutional neural networks (CNN) to solve the problem: 1D-CNN is designed to learn directly from digital data; 2DS-CNN and 2DM-CNN have a more complex architecture, transferring raw waveform into transformed images using Fourier transform to learn essential features. Experimental results on four large data sets, containing 30,000 samples for each, show that the three proposed models achieve superior performance compared to well-known models such as GoogLeNet and AlexNet, with the best accuracy of 95.87%, 99.65%, and 99.76%, respectively. With 5-10% higher performance than other models, the proposed solution has demonstrated the ability to effectively learn features, improve recognition accuracy and speed, and open up the potential for broad applications in virtual assistants, medical recording, and voice commands.


Assuntos
Redes Neurais de Computação , Interface para o Reconhecimento da Fala , Humanos , Fala/fisiologia , Algoritmos
2.
J Biol Chem ; 299(9): 105123, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37536630

RESUMO

Distinct functions mediated by members of the monopolar spindle-one-binder (MOB) family of proteins remain elusive beyond the evolutionarily conserved and well-established roles of MOB1 (MOB1A/B) in regulating tissue homeostasis within the Hippo pathway. Since MOB proteins are adaptors, understanding how they engage in protein-protein interactions and help assemble complexes is essential to define the full scope of their biological functions. To address this, we undertook a proximity-dependent biotin identification approach to define the interactomes of all seven human MOB proteins in HeLa and human embryonic kidney 293 cell lines. We uncovered >200 interactions, of which at least 70% are unreported on BioGrid. The generated dataset reliably recalled the bona fide interactors of the well-studied MOBs. We further defined the common and differential interactome between different MOBs on a subfamily and an individual level. We discovered a unique association between MOB3C and 7 of 10 protein subunits of the RNase P complex, an endonuclease that catalyzes tRNA 5' maturation. As a proof of principle for the robustness of the generated dataset, we validated the specific interaction of MOB3C with catalytically active RNase P by using affinity purification-mass spectrometry and pre-tRNA cleavage assays of MOB3C pulldowns. In summary, our data provide novel insights into the biology of MOB proteins and reveal the first interactors of MOB3C, components of the RNase P complex, and hence an exciting nexus with RNA biology.


Assuntos
Via de Sinalização Hippo , Mapeamento de Interação de Proteínas , Proteínas Serina-Treonina Quinases , Ribonuclease P , Humanos , Células HeLa , Via de Sinalização Hippo/fisiologia , Ribonuclease P/metabolismo , Células HEK293 , Subunidades Proteicas/metabolismo
3.
Int J Gen Med ; 16: 2933-2941, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457752

RESUMO

Objective: To investigate the serum soluble thrombomodulin (sTM) concentration in patients with sepsis-associated acute kidney injury (AKI) and to determine the value of sTM in predicting AKI and mortality in sepsis patients. Methods: This prospective observational study was conducted on 71 patients diagnosed with sepsis according to Sepsis 3 at the Intensive Care Unit, Hue Central Hospital, Vietnam, from September 2021 to February 2023. Results: Among 71 sepsis patients, there were 38 (53.5%) AKI cases, including 16 (22.5%) cases of stage 1 AKI, 14 (19.7%) cases of stage 2 AKI, 8 (11.3%) cases of stage 3 AKI, 16 (22.5%) cases of renal replacement therapy, 28 (39.4%) cases of septic shock, and 21 (29.6%) cases of mortality within 28 days. The concentrations of lactate and IL-6 in the AKI and mortality groups were statistically significantly greater than those in the non-AKI and survival groups (p < 0.05). The serum sTM concentration was 4.33 ng/mL, the serum sTM level in the AKI group was statistically significantly higher than that in the non-AKI group (sTM [4.71 vs 2.54 ng/mL, p < 0.001]), and the serum sTM level in the mortality group was statistically significantly higher than the survival group (sTM [4.78 vs 3.87 ng/mL, p < 0.001]). The AUC of sTM for predicting AKI was 0.864; the AUCs of sTM, IL-6, SOFA, and APACHE II for predicting mortality were 0.811, 0.671, 0.816, and 0.705, respectively. Conclusion: AKI was a prevalent complication among sepsis patients at the ICU. In the AKI and mortality groups, sTM concentration was statistically significantly higher than that in the non-AKI and survival groups. sTM was the predictor of acute kidney injury and mortality in patients with sepsis.

4.
Tissue Eng Part C Methods ; 29(8): 371-380, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37310900

RESUMO

The heart contains diverse endothelial cell types. We sought to characterize the endocardial endothelial cells (EECs), which line the chambers of the heart. EECs are relatively understudied, yet their dysregulation can lead to various cardiac pathologies. Due to the lack of commercial availability of these cells, we reported our protocol for isolating EECs from porcine hearts and for establishing an EEC population through cell sorting. In addition, we compared the EEC phenotype and fundamental behaviors to a well-studied endothelial cell line, human umbilical vein endothelial cells (HUVECs). The EECs stained positively for classic phenotypic markers such as CD31, von Willebrand Factor, and vascular endothelial (VE) cadherin. The EECs proliferated more quickly than HUVECs at 48 h (1310 ± 251 cells vs. 597 ± 130 cells, p = 0.0361) and at 96 h (2873 ± 257 cells vs. 1714 ± 342 cells, p = 0.0002). Yet EECs migrated more slowly than HUVECs to cover a scratch wound at 4 h (5% ± 1% wound closure vs. 25% ± 3% wound closure, p < 0.0001), 8 h (15% ± 4% wound closure vs. 51% ± 12% wound closure, p < 0.0001), and 24 h (70% ± 11% wound closure vs. 90% ± 3% wound closure, p < 0.0001). Finally, the EECs maintained their endothelial phenotype by positive expression of CD31 through more than a dozen passages (three populations of EECs showing 97% ± 1% CD31+ cells in over 14 passages). In contrast, the HUVECs showed significantly reduced CD31 expression over high passages (80% ± 11% CD31+ cells over 14 passages). These important phenotypic differences between EECs and HUVECs highlight the need for researchers to utilize the most relevant cell types when studying or modeling diseases of interest.


Assuntos
Endocárdio , Coração , Suínos , Humanos , Animais , Endocárdio/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Separação Celular/métodos , Células Cultivadas , Endotélio Vascular
5.
Polymers (Basel) ; 15(11)2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37299360

RESUMO

Cellulose, the most abundant natural polymer on earth, has recently gained attention for a large spectrum of applications. At a nanoscale, nanocelluloses (mainly involving cellulose nanocrystals or cellulose nanofibrils) possess many predominant features, such as highly thermal and mechanical stability, renewability, biodegradability and non-toxicity. More importantly, the surface modification of such nanocelluloses can be efficiently obtained based on the native surface hydroxyl groups, acting as metal ions chelators. Taking into account this fact, in the present work, the sequential process involving chemical hydrolysis of cellulose and autocatalytic esterification using thioglycolic acid was performed to obtain thiol-functionalized cellulose nanocrystals. The change in chemical compositions was attributed to thiol-functionalized groups and explored via the degree of substitution using a back titration method, X-ray powder diffraction, Fourier-transform infrared spectroscopy and thermogravimetric analysis. Cellulose nanocrystals were spherical in shape and ca. 50 nm in diameter as observed via transmission electron microscopy. The adsorption behavior of such a nanomaterial toward divalent copper ions from an aqueous solution was also assessed via isotherm and kinetic studies, elucidating a chemisorption mechanism (ion exchange, metal chelation and electrostatic force) and processing its operational parameters. In contrast to an inactive configure of unmodified cellulose, the maximum adsorption capacity of thiol-functionalized cellulose nanocrystals toward divalent copper ions from an aqueous solution was 4.244 mg g-1 at a pH of 5 and at room temperature.

6.
Metabolomics ; 19(6): 58, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37289273

RESUMO

BACKGROUND AND AIMS: SKN-1, a C. elegans transcription factor analogous to the mammalian NF-E2-related factor (Nrf2), has been known to promote oxidative stress resistance aiding nematodes' longevity. Although SKN-1's functions suggest its implication in lifespan modulation through cellular metabolism, the actual mechanism of how metabolic rearrangements contribute to SKN-1's lifespan modulation has yet to be well characterized. Therefore, we performed the metabolomic profiling of the short-lived skn-1-knockdown C. elegans. METHODS: We analyzed the metabolic profile of the skn-1-knockdown worms with nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography-tandem mass spectrometry (LC-MS/MS) and obtained distinctive metabolomic profiles compared to WT worms. We further extended our study with gene expression analysis to examine the expression level of genes encoding all metabolic enzymes. RESULTS: A significant increase in the phosphocholine and AMP/ATP ratio, potential biomarkers of aging, was observed, accompanied by a decrease in the transsulfuration metabolites, NADPH/NADP+ ratio, and total glutathione (GSHt), which are known to be involved in oxidative stress defense. skn-1-RNAi worms also exhibited an impairment in the phase II detoxification system, confirmed by the lower conversion rate of paracetamol to paracetamol-glutathione. By further examining the transcriptomic profile, we found a decrease in the expression of cbl-1, gpx, T25B9.9, ugt, and gst, which are involved in GSHt and NADPH synthesis as well as in the phase II detoxification system. CONCLUSION: Our multi-omics results consistently revealed that the cytoprotective mechanisms, including cellular redox reactions and xenobiotic detoxification system, contribute to the roles of SKN-1/Nrf2 in the lifespan of worms.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Acetaminofen/metabolismo , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Cromatografia Líquida , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Glutationa/metabolismo , Longevidade/genética , Mamíferos/metabolismo , Metabolômica , NADP/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Espectrometria de Massas em Tandem
7.
Exp Mol Med ; 55(5): 871-878, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37121968

RESUMO

Mitochondria are of fundamental importance in programmed cell death, cellular metabolism, and intracellular calcium concentration modulation, and inheritable mitochondrial disorders via mitochondrial DNA (mtDNA) mutation cause several diseases in various organs and systems. Nevertheless, mtDNA editing, which plays an essential role in the treatment of mitochondrial disorders, still faces several challenges. Recently, programmable editing tools for mtDNA base editing, such as cytosine base editors derived from DddA (DdCBEs), transcription activator-like effector (TALE)-linked deaminase (TALED), and zinc finger deaminase (ZFD), have emerged with considerable potential for correcting pathogenic mtDNA variants. In this review, we depict recent advances in the field, including structural biology and repair mechanisms, and discuss the prospects of using base editing tools on mtDNA to broaden insight into their medical applicability for treating mitochondrial diseases.


Assuntos
Genoma Mitocondrial , Doenças Mitocondriais , Humanos , Edição de Genes , Mitocôndrias/genética , Mitocôndrias/metabolismo , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Doenças Mitocondriais/genética , Doenças Mitocondriais/terapia , Doenças Mitocondriais/metabolismo
8.
Genes (Basel) ; 14(2)2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36833410

RESUMO

Programmable nucleases, such as zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas, are widely accepted because of their diversity and enormous potential for targeted genomic modifications in eukaryotes and other animals. Moreover, rapid advances in genome editing tools have accelerated the ability to produce various genetically modified animal models for studying human diseases. Given the advances in gene editing tools, these animal models are gradually evolving toward mimicking human diseases through the introduction of human pathogenic mutations in their genome rather than the conventional gene knockout. In the present review, we summarize the current progress in and discuss the prospects for developing mouse models of human diseases and their therapeutic applications based on advances in the study of programmable nucleases.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Humanos , Animais , Camundongos , Endonucleases/genética , Nucleases dos Efetores Semelhantes a Ativadores de Transcrição , Genoma
9.
Int J Mol Sci ; 24(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36674697

RESUMO

Anoctamin1 (ANO1), a calcium-activated chloride channel, is involved in the proliferation, migration, and invasion of various cancer cells including head and neck squamous cell carcinoma, lung cancer, and prostate cancer. Inhibition of ANO1 activity or downregulation of ANO1 expression in these cancer cells is known to exhibit anticancer effects. Resveratrol, a natural polyphenol abundant in wines, grapes, berries, soybeans, and peanuts, shows a wide variety of biological effects including anti-inflammatory, antioxidant, and anticancer activities. In this study, we investigated the effects of two stereoisomers of resveratrol on ANO1 activity and found that cis- and trans-resveratrol inhibited ANO1 activity with different potencies. Cis- and trans-resveratrol inhibited ANO1 channel activity with IC50 values of 10.6 and 102 µM, respectively, and had no significant effect on intracellular calcium signaling at 10 and 100 µM, respectively. In addition, cis-resveratrol downregulated mRNA and protein expression levels of ANO1 more potently than trans-resveratrol in PC-3 prostate cancer cells. Cis- and trans-resveratrol significantly reduced cell proliferation and cell migration in an ANO1-dependent manner, and both resveratrol isomers strongly increased caspase-3 activity, PARP cleavage, and apoptotic sub-G1 phase ratio in PC-3 cells. These results revealed that cis-resveratrol is a potent inhibitor of ANO1 and exhibits ANO1-dependent anticancer activity against human metastatic prostate cancer PC-3 cells.


Assuntos
Neoplasias de Cabeça e Pescoço , Neoplasias da Próstata , Masculino , Humanos , Resveratrol/farmacologia , Células PC-3 , Anoctamina-1/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Proteínas de Neoplasias/metabolismo
10.
Med Arch ; 77(6): 433-439, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38313115

RESUMO

Background: Thrombomodulin (TM) is a type-1 trans-membrane glycoprotein on endothelial cells which is known to be involved in various biochemical pathways. TM can be detected in biological fluids such as blood and urine under many forms. Soluble thrombomodulin (sTM), consist of various particles of TM, is the predominant agent which is created by enzymatic or chemical catalysis of the whole protein under divergent conditions. TM plays a vital role in protein C system and is crucial in the pathogenesis of Sepsis. Objective: To identify the serum level of soluble thrombomodulin (sTM) in groups of patients: sepsis and septic shock including their survival and fatal in-hospital outcome; and validate the death prediction of serum sTM in patients with sepsis. Methods: This prospective observational study was conducted in 63 patients who were diagnosed with sepsis, septic shock according to Sepsis 3 criteria at the ICU Department of Hue Central Hospital, Vietnam, from 3/2022 to 3/2023. Results: Twenty participants developed septic shock (31.7%), morality within 28-days was 19 patients (30.2%), 22 patients complicated with acute kidney injury that necessitated renal replacement therapy (34.9%), 30 patients required mechanical ventilation (47.6%), the median length of ICU stay was 8 (3-28) days. Serum level of lactate and creatinine were significantly higher in septic shock group compared with sepsis and survival group (p<0.05). The median sTM level in septic shock group and fatal group were 4.68(3.38-6.46) ng/mL and 4.68 (1.69-6.46) ng/mL, respectively. These results were significantly higher than sepsis group [3.62 (1.51-1.94) ng/mL] and survival group [3.73 (1.51-5.9) ng/mL] (p<0.05). The death predictive power of DIC score, APACHE II score, creatinine, sTM and SOFA presented with AUC values of 0.723, 0.726, 0.777, 0.803 and 0.807, respectively. There were no significant difference of serum level IL-6 and PCT between survival and fatal group. The median DIC score in fatal group was 7 (3-7), which was significantly higher than survival group 4 (2-7) (p= 0.001). Conclusion: Sepsis is a common diagnosis among ICU settings which links the critically ill patients to higher complications and mortalities. Serum level of sTM in septic shock and fatal groups were significantly higher than sepsis and survival groups. sTM is a reliable marker and should be used in predict severity and mortality in sepsis patients.


Assuntos
Sepse , Choque Séptico , Humanos , Creatinina , Células Endoteliais , Prognóstico , Curva ROC , Choque Séptico/complicações , Trombomodulina
11.
RSC Adv ; 12(54): 35436-35444, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36540239

RESUMO

As the most abundant natural biopolymer on earth, celluloses have long-term emerged as a capable platform for diverse purposes. In the context of metal nanoparticles applied to catalysis, the alternatives to traditional catalyst supports by using biomass-derived renewable materials, likely nanocelluloses, have been paid a great effort, in spite of being less exploited. In this study, cellulose nanocrystals were isolated from corn leaf via chemical treatment involving alkalizing, bleaching and acid hydrolysis. The crystallinity of obtained cellulose was evaluated in each step, focusing on the effects of reactant concentration and reaction time. Cellulose nanocrystals were characterized by powder X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), evidencing the presence of cellulose nanospheres (crystallinity index of 67.3% in comparison with 38.4% from untreated raw material) in the size range of 50 nm. Without using any additional surfactants or stabilizers, silver nanoparticles (AgNPs) well-dispersed on the surface of cellulose nanocrystals (silver content of 5.1 wt%) could be obtained by a simple chemical reduction using NaBH4 at room temperature. The catalytic activity was evaluated in the selective reductions of 4-nitrophenol towards 4-aminophenol and methyl orange towards aromatic amine derivatives in water at room temperature. The effects of catalyst amount and reaction time were also studied in both reduction processes, showing near-quantitative conversions within 5 minutes and obeying the pseudo-first-order kinetics, with the apparent kinetic rate constants of 8.9 × 10-3 s-1 (4-nitrophenol) and 13.6 × 10-3 s-1 (methyl orange). The chemical structure of the catalytic system was found to be highly stable during reaction and no metal leaching was detected in reaction medium, evidencing adaptability of cellulose nanocrystals in immobilizing noble metal nanoparticles.

12.
RSC Adv ; 12(39): 25753-25763, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36199345

RESUMO

A green synthesis using extract from Citrus maxima peel was developed to fabricate Au-Ce catalysts for the reduction of p-nitrophenol (PNP). Au nanoparticles with a diameter of 6.6 ± 2.5 nm were deposited onto the surface of CeO2 nanorods with a length of 33.1 ± 15.0 nm and a diameter of 7.1 ± 2.1 nm. The mesoporous and non-porous capillary structures of these materials were observed. The interaction between Au and CeO2 increased the specific surface area, pore diameter, and pore volume compared with pure CeO2 (90 m2 g-1, 23.8 Å, and 0.110 cm3 g-1 versus 72 m2 g-1, 23.0 Å, and 0.089 cm3 g-1). The splitting peaks of the surface oxygen and their shifting at lower temperatures compared with CeO2 nanorods were found thanks to the Au-CeO2 interaction, suggesting that their reduction occurred more easily. The synthesized Au-Ce catalysts exhibited excellent activity in the reduction of PNP to p-aminophenol. The 0.2Au-Ce catalyst was the most efficient one for PNP reduction, enabling the conversion of PNP in 30 minutes with a catalyst concentration of 20 mg L-1 and a PNP/NaBH4 molar ratio of 1/200. Moreover, the 0.2Au-Ce catalyst could be reused for at least five consecutive cycles without considerable loss of its activity.

13.
Nucleic Acids Res ; 50(14): 8154-8167, 2022 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-35848927

RESUMO

RNase P is a ribonucleoprotein (RNP) that catalyzes removal of the 5' leader from precursor tRNAs in all domains of life. A recent cryo-EM study of Methanocaldococcus jannaschii (Mja) RNase P produced a model at 4.6-Å resolution in a dimeric configuration, with each holoenzyme monomer containing one RNase P RNA (RPR) and one copy each of five RNase P proteins (RPPs; POP5, RPP30, RPP21, RPP29, L7Ae). Here, we used native mass spectrometry (MS), mass photometry (MP), and biochemical experiments that (i) validate the oligomeric state of the Mja RNase P holoenzyme in vitro, (ii) find a different stoichiometry for each holoenzyme monomer with up to two copies of L7Ae, and (iii) assess whether both L7Ae copies are necessary for optimal cleavage activity. By mutating all kink-turns in the RPR, we made the discovery that abolishing the canonical L7Ae-RPR interactions was not detrimental for RNase P assembly and function due to the redundancy provided by protein-protein interactions between L7Ae and other RPPs. Our results provide new insights into the architecture and evolution of RNase P, and highlight the utility of native MS and MP in integrated structural biology approaches that seek to augment the information obtained from low/medium-resolution cryo-EM models.


Assuntos
Proteínas Arqueais , Methanocaldococcus , Ribonuclease P , Proteínas Arqueais/metabolismo , Methanocaldococcus/enzimologia , Methanocaldococcus/genética , Conformação Proteica , RNA de Transferência/metabolismo , Ribonuclease P/metabolismo , Relação Estrutura-Atividade
14.
Ocul Surf ; 25: 92-100, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35690236

RESUMO

PURPOSE: MiR-146a upregulated in limbus vs. central cornea and in diabetic vs. non-diabetic limbus has emerged as an important immune and inflammatory signaling mediator in corneal epithelial wound healing. Our aim was to investigate the potential inflammation-related miR-146a target genes and their roles in normal and impaired diabetic corneal epithelial wound healing. METHODS: Our previous data from RNA-seq combined with quantitative proteomics of limbal epithelial cells (LECs) transfected with miR-146a mimic vs. mimic control were analyzed. Western blot and immunostaining were used to confirm the expression of miR-146a inflammatory target proteins in LECs and organ-cultured corneas. Luminex assay was performed on conditioned media at 6- and 20-h post-wounding in miR-146a mimic/inhibitor transfected normal and diabetic cultured LECs. RESULTS: Overexpression of miR-146a decreased the expression of pro-inflammatory TRAF6 and IRAK1 and downstream target NF-κB after challenge with lipopolysaccharide (LPS) or wounding. Additionally, miR-146a overexpression suppressed the production of downstream inflammatory mediators including secreted cytokines IL-1α, IL-1ß, IL-6 and IL-8, and chemokines CXCL1, CXCL2 and CXCL5. These cytokines and chemokines were upregulated in normal but not in diabetic LEC during wounding. Furthermore, we achieved normalized levels of altered secreted cytokines and chemokines in diabetic wounded LEC via specific inhibition of miR-146a. CONCLUSION: Our study documented significant impact of miR-146a on the expression of inflammatory mediators at the mRNA and protein levels during acute inflammatory responses and wound healing, providing insights into the regulatory role of miR-146a in corneal epithelial homeostasis in normal and diabetic conditions.


Assuntos
Córnea , Diabetes Mellitus , MicroRNAs , Cicatrização , Córnea/metabolismo , Citocinas/metabolismo , Humanos , Mediadores da Inflamação , MicroRNAs/genética
15.
Methods Mol Biol ; 2508: 9-17, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35737229

RESUMO

Suspension cell lines grow free-floating in the cell culture media without any attachment to the culture plate/vessel. Suspension cells typically mimic cells that exist in the circulation of multicellular animals such as mouse and humans. Generally, cell lines derived from the blood such as lymphocytes, megakaryocyte, and neutrophils grow in suspension. These cell lines can be used for experimental studies to understand the biology/biochemistry of cancer cells. In this chapter, procedures for working with suspension cell lines are provided, including protocols for thawing, culturing, and cryopreserving cancer cell lines. Importantly, this chapter demonstrates the best practices required to work with suspension cell lines, to minimize the risk of contaminations from adventitious microorganisms or from other cell lines.


Assuntos
Técnicas de Cultura de Células , Neoplasias , Animais , Técnicas de Cultura de Células/métodos , Linhagem Celular , Camundongos , Suspensões
16.
Integr Blood Press Control ; 15: 43-51, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35418780

RESUMO

Objective: This study aims to determine the serum levels of NT-proBNP in women with preeclampsia with and without severe signs and to evaluate the cardiovascular risks in these two groups of participants. Methods: A descriptive cross-sectional study was conducted on 52 women with preeclampsia in the Department of Gynecology and Obstetrics - Hue Central Hospital, from August 2019 to September 2020. Results: In preeclampsia women, the rate of hypertension in stage 3, stage 2, and stage 1 were 46.1%, 32.7%, and 21.2%, respectively. The average Sokolow-Lyon index in the preeclampsia group with and without severe signs was 22.25 ± 7.38mm, 20.16 ± 5.54mm, respectively. The average left ventricular mass index in the group of preeclampsia patients without and with severe signs was 92.27 ± 14.56g/m2 and 120.68 ± 16.47g/m2, respectively. The average ejection fraction in the group of preeclampsia patients without severe signs and with severe signs was 65.11 ± 3.45%, 56.21 ± 7.12%, correspondingly. In contrast, the difference between the two groups was statistically significant with p < 0.05. The plasma NT-proBNP level in the preeclampsia group without severe signs was 349.12 ± 93.51pg/mL, whereas the concentration in the preeclampsia group with severe signs was 725.32 ± 290.46pg/mL (p < 0.05). Conclusion: The NT-proBNP level was statistically significantly increased in the patients with preeclampsia. Analyzing and comparing the figures and changes found in two groups of PE patients, with and without severe signs, we suggest that women diagnosed with PE with severe signs have a higher risk of developing cardiovascular problems forthwith and henceforth.

17.
J Ethnopharmacol ; 289: 115061, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35114342

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Flos Magnoliae (the dried flower buds of Magnolia biondii Pamp, FM) is a known herbal traditional medicine used for the symptomatic relief of nasal congestion and rhinorrhea caused by rhinitis and sinusitis. Magnolol, a neolignan from the magnolia family, is a secondary metabolite known to have anti-allergic and anti-inflammatory effects. However, the underlying mechanisms and therapeutic effect of magnolol in the treatment of allergic rhinitis (AR) remain elusive. AIMS OF THE STUDY: Anoctamin 1 (ANO1), a calcium-activated anion channel, mediates mucus and electrolyte secretion in nasal airway epithelial cells, whereas calcium release-activated calcium channel protein 1 (ORAI1) participates in the activation of T-lymphocytes and mast cells. The aim of our study is to understand the mechanisms of action of magnolol against AR, i.e., whether it acts through the modulation of ANO1 and ORAI1 channels that are expressed in nasal epithelial cells and T-lymphocytes, respectively. MATERIALS AND METHODS: Whole-cell patch clamp was used to record the activity of ORAI1 and ANO1 ion channels in ORAI1 or ANO1 overexpressed HEK293T cells, while the Ussing chamber apparatus was used to measure electrolyte transport via the epithelium, in Calu-3 cells cultured in an air-liquid interface. Additionally, calcium imaging of Jurkat T-lymphocytes was used to assess changes in the intracellular calcium concentration. Magnolol toxicity was assessed using the CCK-8 assay, and its effect on T-lymphocyte proliferation was measured by labeling human primary T-lymphocytes with carboxyfluorescein succinimidyl ester. Finally, OVA-induced Balb/c mice were employed to evaluate the effect of magnolol on nasal symptoms, as well as cytokine and eosinophil infiltration in AR. RESULTS: Magnolol inhibits ORAI1 and ANO1 channels in a concentration-dependent manner. Magnolol (30 µM) inhibits anti-CD3 induced cellular proliferation and production of IL-2 via ORAI1 channels in T-lymphocytes. Further, ATP-induced electrolyte transport mediated by ANO1 channels is significantly inhibited by magnolol in IL-4 sensitized Calu-3 cells. Notably, 300 µM magnolol significantly attenuates cytokine and eosinophil infiltration, thus alleviating AR symptoms in mice OVA-induced AR. CONCLUSION: Magnolol may be a promising therapeutic agent for the treatment and prevention of AR.


Assuntos
Antialérgicos/farmacologia , Compostos de Bifenilo/farmacologia , Lignanas/farmacologia , Magnolia/química , Rinite Alérgica/tratamento farmacológico , Animais , Anoctamina-1/antagonistas & inibidores , Antialérgicos/administração & dosagem , Antialérgicos/isolamento & purificação , Compostos de Bifenilo/administração & dosagem , Compostos de Bifenilo/isolamento & purificação , Linhagem Celular Tumoral , Citocinas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Flores , Células HEK293 , Humanos , Lignanas/administração & dosagem , Lignanas/isolamento & purificação , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Neoplasias/antagonistas & inibidores , Proteína ORAI1/antagonistas & inibidores , Ovalbumina , Técnicas de Patch-Clamp
18.
J Immunol ; 207(12): 3004-3015, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34772696

RESUMO

Extracellular vesicles (EVs) are membrane-encapsulated nanoparticles that carry bioactive cargo, including proteins, lipids, and nucleic acids. Once taken up by target cells, EVs can modify the physiology of the recipient cells. In past studies, we reported that engagement of the glycophosphatidylinositol-anchored receptor CD24 on B lymphocytes (B cells) causes the release of EVs. However, a potential function for these EVs was not clear. Thus, we investigated whether EVs derived from CD24 or IgM-stimulated donor WEHI-231 murine B cells can transfer functional cargo to recipient cells. We employed a model system where donor cells expressing palmitoylated GFP (WEHI-231-GFP) were cocultured, after stimulation, with recipient cells lacking either IgM (WEHI-303 murine B cells) or CD24 (CD24 knockout mouse bone marrow B cells). Uptake of lipid-associated GFP, IgM, or CD24 by labeled recipient cells was analyzed by flow cytometry. We found that stimulation of either CD24 or IgM on the donor cells caused the transfer of lipids, CD24, and IgM to recipient cells. Importantly, we found that the transferred receptors are functional in recipient cells, thus endowing recipient cells with a second BCR or sensitivity to anti-CD24-induced apoptosis. In the case of the BCR, we found that EVs were conclusively involved in this transfer, whereas in the case in the CD24 the involvement of EVs is suggested. Overall, these data show that extracellular signals received by one cell can change the sensitivity of neighboring cells to the same or different stimuli, which may impact B cell development or activation.


Assuntos
Vesículas Extracelulares , Receptores de Antígenos de Linfócitos B , Animais , Linfócitos B/metabolismo , Vesículas Extracelulares/metabolismo , Imunoglobulina M/metabolismo , Lipídeos , Camundongos , Receptores de Antígenos de Linfócitos B/metabolismo
19.
Int J Mol Sci ; 22(19)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34639190

RESUMO

Calcium signaling plays a vital role in the regulation of various cellular processes, including activation, proliferation, and differentiation of T-lymphocytes, which is mediated by ORAI1 and potassium (K+) channels. These channels have also been identified as highly attractive therapeutic targets for immune-related diseases. Licochalcone A is a licorice-derived chalconoid known for its multifaceted beneficial effects in pharmacological treatments, including its anti-inflammatory, anti-asthmatic, antioxidant, antimicrobial, and antitumorigenic properties. However, its anti-inflammatory effects involving ion channels in lymphocytes remain unclear. Thus, the present study aimed to investigate whether licochalcone A inhibits ORAI1 and K+ channels in T-lymphocytes. Our results indicated that licochalcone A suppressed all three channels (ORAI1, Kv1.3, and KCa3.1) in a concentration-dependent matter, with IC50 values of 2.97 ± 1.217 µM, 0.83 ± 1.222 µM, and 11.21 ± 1.07 µM, respectively. Of note, licochalcone A exerted its suppressive effects on the IL-2 secretion and proliferation in CD3 and CD28 antibody-induced T-cells. These results indicate that the use of licochalcone A may provide an effective treatment strategy for inflammation-related immune diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Chalconas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/antagonistas & inibidores , Canal de Potássio Kv1.3/antagonistas & inibidores , Proteína ORAI1/antagonistas & inibidores , Linfócitos T/efeitos dos fármacos , Cálcio/metabolismo , Sinalização do Cálcio , Células HEK293 , Humanos , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/genética , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Células Jurkat , Canal de Potássio Kv1.3/genética , Canal de Potássio Kv1.3/metabolismo , Proteína ORAI1/genética , Proteína ORAI1/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo
20.
Trends Biochem Sci ; 46(12): 976-991, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34511335

RESUMO

RNase P is an essential enzyme that catalyzes removal of the 5' leader from precursor transfer RNAs. The ribonucleoprotein (RNP) form of RNase P is present in all domains of life and comprises a single catalytic RNA (ribozyme) and a variable number of protein cofactors. Recent cryo-electron microscopy structures of representative archaeal and eukaryotic (nuclear) RNase P holoenzymes bound to tRNA substrate/product provide high-resolution detail on subunit organization, topology, and substrate recognition in these large, multisubunit catalytic RNPs. These structures point to the challenges in understanding how proteins modulate the RNA functional repertoire and how the structure of an ancient RNA-based catalyst was reshaped during evolution by new macromolecular associations that were likely necessitated by functional/regulatory coupling.


Assuntos
RNA Catalítico , Ribonuclease P , Microscopia Crioeletrônica , Conformação de Ácido Nucleico , RNA , RNA Catalítico/metabolismo , RNA de Transferência/metabolismo , Ribonuclease P/química , Ribonuclease P/genética , Ribonuclease P/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...