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Concerns over the spread of non-native species in aquatic environments have led to the need for effective methods to prevent and control their spread while protecting native species. This study investigated the potential of yeast vacuolar enzymes as a natural hatching inhibitor for controlling aquatic organisms. Hatching experiments with Daphnia magna eggs demonstrated that exposure to yeast vacuole enzymes inhibited hatching in a concentration-dependent manner, suggesting their potential as an effective inhibitor of egg hatching in aquatic organisms. Interestingly, the protease used for comparative purposes did not inhibit hatching, but instead increased the mortality of hatched D. magna. Additionally, chorionic changes were observed in non-hatched D. magna eggs and zebrafish eggs exposed to yeast vacuole enzymes, suggesting that the enzyme can alter the chorion and interfere with hatching. These findings suggest that yeast vacuolar enzymes may be a promising and natural management tool for controlling the spread of harmful aquatic organisms, and further research is warranted to explore their potential for species-specific control.
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Saccharomyces cerevisiae , Pez Cebra , Animales , Daphnia , Organismos Acuáticos , VacuolasRESUMEN
The majority of the vitamin D that is present in the blood binds to vitamin D binding protein (VDBP) and circulates in the form of a complex (VDBP-Complex). Knowing the level of vitamin D in the body is crucial for vitamin D-related treatments so that the right dosage of vitamin D can be given. In other words, it is essential to distinguish between the protein VDBP and the complex form bound to vitamin D. As a novel way for the detection of VDBP-Complex, a more effective phage display methodology was applied in this study along with the addition of two approaches. In order to screen a sequence specific to the target only, the pre-binding method and after-binding method were performed. VDBP-Complex was directly coated on the petri dishes. In order to select phages that specifically bind to the VDBP-Complex, random phages were attached, and selected by 7 times of biopanning. Individual DNA sequences were analyzed for each biopanning to find specific peptide sequences for VDBP-Complex. The affinity of binding phages was verified by ELISA assay using an anti-M13 antibody. The phage having a sequence of SFTKTSTFTWRD (called as M3) has shown the highest binding affinity to VDBP-Complex. As a result of the removal test of VDBP-Complex using magnetic beads conjugated with M3 peptide, it was confirmed that significant decrease of VDBP-Complex. The unique characteristic of the M3 sequence was confirmed through a sequence-modified peptide (SFT motif). That is, it is expected that the M3 peptide may be used to determine the vitamin D levels in the blood.
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Bacteriófagos , Vitamina D , Péptidos/metabolismo , Vitaminas , Proteína de Unión a Vitamina D , Técnicas de Visualización de Superficie Celular/métodos , Ensayo de Inmunoadsorción Enzimática , Bacteriófagos/metabolismoRESUMEN
The vacuoles of the yeast Saccharomyces cerevisiae are closely related to mammalian lysosomes and play a role in macromolecular degradation due to the hydrolytic enzymes present inside. The vacuoles also regulate osmotic pressure and control cellular homeostasis. In previous results, vacuoles were shown to activate the immune response of macrophages by promoting the production of immune-mediated transporters nitric oxide (NO), reactive oxygen species (ROS), and pro-inflammatory cytokines. In this study, the effects of vacuoles on the phagocytosis activity of RAW264.7 cells and their potential as immune enhancers were evaluated, and receptors capable of recognizing vacuoles were examined. An investigation using the phagocytes assay showed that phagocytosis activity increased by the vacuole. Besides, after treatment with TLR2/4 inhibitor, the expression of pro-inflammatory cytokines by vacuoles was significantly reduced and the inducible nitric oxide synthase (iNOS) protein was also significantly reduced. However, treatment with a TLR2 inhibitor did not reduce the production of interleukin-6 (IL)-6, a pro-inflammatory cytokine. As a result of confirming the activation of TLR2/4 using Western blot and immunofluorescence (IF), the TLR2/4 protein expression and fluorescence intensity increased depending on the concentration of vacuoles. Yeast vacuoles significantly upregulate protein expression of p-p65/p-p38 MAPKs. In summary, the vacuoles isolated from S. cerevisiae in macrophages have increased phagocytic ability at a concentration of 20 (µg/ml) and can function as immune-enhancing agent suggesting that TLR2/4 mediated the p38 MAPK/nuclear factor kappa B signaling pathway.
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Fagocitosis , Saccharomyces cerevisiae , Receptor Toll-Like 2 , Receptor Toll-Like 4 , Animales , Citocinas/metabolismo , Lipopolisacáridos , FN-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Saccharomyces cerevisiae/metabolismo , Receptor Toll-Like 2/metabolismo , Vacuolas/metabolismo , Ratones , Células RAW 264.7 , Receptor Toll-Like 4/metabolismoRESUMEN
In this study, we were investigated the effect of lysosomal extracts (named as lysosomal enzymes) on extending the vase life of cut flowers. The results confirmed that senescence of cut freesia treated with lysosomal enzymes delayed. Also, the results for cut roses and lilies showed a similar pattern. In the case of them the fresh weight was lower than that of the control group, but time the ornamental value was retained increased by about 2 days. The reasons have explained as results by the change including stomata, accumulation of microbial population, and soluble carbohydrate contents. In conclusion, pretreatment with lysosomal enzymes has enhanced vase life and ornamental value of cut flowers. It has an important significance in improving the marketability of cut flowers in the flower industry. Therefore, lysosomal enzymes have the potential to be used sufficiently as eco-friendly and effective materials for pretreatment agents in the cut flower industry.
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Flores , Lisosomas , Carbohidratos/farmacologíaRESUMEN
PURPOSE: To investigate the effect of roughness and drying time of dentin as well as the number of coats of a self-adhesive composite-cement primer on the bond strength of self-adhesive composite cement. MATERIAL AND METHODS: Sixty human teeth were prepared and assigned to 12 groups (n = 5), according to three experimental factors: 1) dentin surface roughness, rough or fine, as achieved by 250- and 600-grit silicon carbide papers, respectively; 2) dentin wetness based on air-drying time (5 or 10 s); and 3) the self-adhesive composite-cement primer applications (no-coat, 1-coat, and 2-coat). Composite resin blocks were made with hybrid composite resin (M1 GraceFil) and cemented with G-CEM ONE (both GC). Cement-dentin sticks (12) were prepared, and the microtensile bond strength (µTBS) test was performed. Failure modes were observed with a stereomicroscope (40X), and bonding interfaces were evaluated with confocal laser scanning microscopy (CLSM). Statistical analysis was performed using three-way ANOVA and Tukey's post-hoc comparisons test (α = 0.05). RESULTS: Dentin roughness (250-grit > 600-grit, p = 0.000), drying time (5-s drying > 10-s drying, p = 0.000), and primer application (no-coat < 1-coat = 2-coat, p = 0.000) had significant effects on bond strength. These factors also showed significant interactions with each other (p = 0.003). The highest µTBS (31.8 ± 3.1 MPa) was observed in the 1-coat/fine roughness/10-s drying group and the lowest µTBS (13.4 ± 2.7 MPa) in the no-coat/coarse roughness/5-s drying group. CLSM showed higher penetration of cement in the primer-coated groups compared to that in the no-coat groups. CONCLUSION: Bond strength between the self-adhesive composite cement and dentin was higher in the fine-roughness dentin group than in the coarse-roughness dentin group, and in the 5-s drying group compared to the 10-s drying group. Applying a primer to dentin improved bond strength of the self-adhesive composite cement.
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Recubrimiento Dental Adhesivo , Cementos de Resina , Resinas Compuestas/química , Cementos Dentales , Materiales Dentales/química , Dentina , Recubrimientos Dentinarios/química , Cementos de Ionómero Vítreo/química , Humanos , Ensayo de Materiales , Cementos de Resina/química , Propiedades de Superficie , Resistencia a la TracciónRESUMEN
The treatment of teeth with severely calcified canals is a difficult procedure for clinicians. Procedural accidents such as drill path deviation or perforation of the root canal often occur. 3D-printed directional guides made using CBCT and CAD/CAM can help the clinician to accurately drill in the original root canal direction. Furthermore, chairside operating times and excessive loss of tooth structure are reduced, and the risk of perforation is avoided. The present case report describes two cases of calcified root canals with path deviations that were retreated utilizing a guided endodontic technique.
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Tomografía Computarizada de Haz Cónico , Cavidad Pulpar , Humanos , Impresión Tridimensional , Retratamiento , Tratamiento del Conducto RadicularRESUMEN
The signal peptide sequence is known to increase transport efficiency to organelles in eukaryotic cells. In this study, we focus on the signal peptide of the vacuolar protein for vacuolar targeting. The signal peptide sequence QRPL of carboxypeptidase Y (CPY) was inserted inside the interest protein that does not locate in the vacuole for vacuolar targeting. We constructed recombinant strains MBTL-Q-DJ1 and MBTL-Q-DJ2 containing QRPL and green florescent protein (GFP) or aldehyde dehydrogenase 6 (ALD6), respectively. The protein location was then confirmed by confocal microscopy. Fascinatingly, the green fluorescent protein that contains QRPL inside the sequence could be expressed faster than its natural form (within 1â¯h after induction). Also, the aldehyde removal activity of ALD6 protein in the recombinant yeast was then analyzed by measuring the luminescent intensity in Vibrio fischeri. We confirmed that MBTL-Q-DJ2 containing ALD6 protein has the aldehydes-reducing ability, and in particular, the highest efficiency showed at 500⯵g/µL of vacuolar enzyme. In summary, the signal peptide QRPL could be used not only to transport proteins accurately to vacuole but also to improve the protein activity and shorten the induction time.
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Proteínas de Saccharomyces cerevisiae , Vacuolas , Catepsina A/genética , Señales de Clasificación de Proteína/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genéticaRESUMEN
The study of senescence preservative on cut flowers helps boost the commercial value of flowers. Senescence in cut flower is associated with an increase of ethylene production, and is significantly influenced by ethylene pathway. This study was conducted to investigate whether S-adenosyl-L-methionine (SAM) and aminocyclopropane-1-carboxylic acid (ACC) involved in the ethylene synthesis process are correlated with the lysosome. The alterations of lysosome which was treated with the ethylene precursors ACC and SAM in HeLa cell using the confocal laser scanning microscope were investigated. According to the experimental results, the activity of lysosomes increased concentration dependently by ACC treatment, however, no change was observed by SAM treatment. In addition, Liquid chromatography-mass spectrometry (LC/MS) analysis was performed to confirm the effect of lysosomal enzyme (LE) extracted from egg white on ACC reduction, but no change was observed. On the contrary, to confirm the effect of ACC on lysosomes, lysosomes were extracted from HeLa cells treated with 5 mM ACC and confirmed by FE-SEM. The results showed that the size of lysosomes treated with ACC is larger than that of the control, which was treated with distilled water. The lysosomes in the control group were distributed in various ranges from 0 to 800 nm, but those treated with 5 mM ACC were in the range of 400 nm to 800 nm or more. Therefore, lysosomes had no effect on ACC, the precursor of ethylene, the aging hormone of cut flowers, however, ACC had effect on lysosomes.
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Aminoácidos Cíclicos/farmacología , Lisosomas/ultraestructura , S-Adenosilmetionina/farmacología , Cromatografía Liquida , Células HeLa , Humanos , Lisosomas/efectos de los fármacos , Espectrometría de Masas , Microscopía Confocal , Tamaño de la PartículaRESUMEN
Parabens are alkyl esters of 4-hydroxybenzoic acid, which is derived from a family of synthetic esters of p-hydroxybenzoic acid. Among all the kinds of paraben, two parabens (methyl paraben, MP; and n-propyl paraben, PP) are the most generally used as preservatives in personal care products, such as cosmetics, pharmaceuticals, and food also, and are often presented together. However, a number of studies have reported that the toxicity of parabens affects the water environment, and human as well. This study utilized M13 phage display technology to provide easy, efficient, and relatively inexpensive methods to identify peptides that bind to MP and PP, respectively, to remove in wastewater. At first, biopanning was performed, to sort MP and PP specific binding phages, and three cases of experiment, including negative control (NC), which could sort unspecific binding phage, were conducted at the same time. Phage binding affinity tests were substituted by concentration reduction using antibody conjugated magnetic beads, and paraben concentration was measured by HPLC. Analysis showed that the MP concentration reduction of 38% was the highest in M4 phage, while the PP concentration reduction of 44% was the highest in P3 phage. We successfully screened two peptides specific to MP and PP, namely, MP4 and PP3, respectively; the results showed that the MP concentration reduction in MP4 was the highest at 44%, and the PP concentration reduction in PP3 was the highest at 39%, and their specificity was measured by the capture rate between target and control. In conclusion, the phage display technique shows applicability to the removal of parabens in water; furthermore, it also shows the possibility of the detection or removal of other chemicals.
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Bacteriófagos , Parabenos , Técnicas de Visualización de Superficie Celular , Humanos , Péptidos , Conservadores FarmacéuticosRESUMEN
Transforming growth factor-ß (TGF-ß) promotes tumor invasion and metastasis by inducing epithelial-mesenchymal transition (EMT). EMT is often related with acquisition of stemness characteristics. The objective of this study was to determine whether EMT and stemness characteristics induced by TGF-ß might be associated with epigenetic regulation in lung cancer. A human normal lung epithelial cell line and four lung cancer cell lines were treated with TGF-ß. Transcriptome analysis of BEAS-2B and A549 cells incubated with TGF-ß were analyzed through next-generation sequencing (NGS). Western blotting was carried out to investigate expression levels of epithelial and mesenchymal markers. Wound healing and Matrigel invasion assay, sphere formation assay, and in vivo mice tumor model were performed to evaluate functional characteristics of EMT and stemness acquisition. To investigate whether activation of EMT and stem cell markers might be involved in epigenetic regulation of lung cancer, experiment using a DNA methyltransferase inhibitor (5-azacytidine, AZA), methylation-specific PCR (MSP) and bisulfite sequencing were performed. NGS revealed changes in expression levels of EMT markers (E-cadherin, N-cadherin, fibronectin, vimentin, slug and snail) and stem cell markers (CD44 and CD87) in both BEAS-2B and A549 cells. Functional analysis revealed increased migration, invasion, sphere formation, and tumor development in mice after TGF-ß treatment. Expression of slug and CD87 genes was activated following treatment with AZA and TGF-ß. MSP and bisulfite sequencing indicated DNA demethylation of slug and CD87 genes. These results suggest that TGF-ß induced EMT and cancer stemness acquisition could be associated with activation of slug and CD87 gene by their promoter demethylation.
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Epigénesis Genética/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Neoplasias Pulmonares/genética , Células Madre/patología , Factor de Crecimiento Transformador beta/farmacología , Animales , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Células Epiteliales/patología , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Ratones , Regiones Promotoras Genéticas/efectos de los fármacos , Células Madre/metabolismo , Cicatrización de Heridas/efectos de los fármacosRESUMEN
The aim of this study was to investigate the effect of G-CEM One Primer (GCOP) and self-etching adhesive on the microtensile bond strength (µTBS) between self-adhesive resin cement G-CEM One (GCO) and dentin. Teeth were sectioned to expose the flat dentin surface and randomly assigned into five groups (n = 15) according to the dentin surface treatment: 1) no surface treatment, 2) GCOP, 3) All-Bond Universal (ABU), 4) GCOP followed by ABU (GCOP/ABU), 5) ABU followed by GCOP (ABU/GCOP). The composite resin blocks were bonded to the dentin surface using GCO. The specimens were stored in distilled water at 37 °C for 24 h, then sectioned into sticks (1 mm × 10 mm). The µTBS values were statistically analyzed using 1-way analysis of variance (ANOVA) and Tukey's honestly significant difference (HSD) test (α = 0.05) and failure mode was examined under a stereomicroscope. The bonding interface of each specimen was evaluated using confocal laser scanning microscopy. The GCOP group exhibited the highest µTBS value and there were no significant differences observed between GCOP, GCOP/ABU, ABU/GCOP groups (p > 0.05). The use of GCOP with GCO results in the improved µTBS between GCO and dentin. In conclusion, using only GCOP with GCO for bonding of indirect restoration is extremely simple and increasing bond strength.
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BACKGROUND/AIM: KRAS is one of the frequently mutated genes in human cancers and often relates with drug resistance and poor prognosis. PANAMutyper™ is a novel technology that integrates PNAClamp™ and PANA S-Melting™. In the present study, PANAMutyper™ and PNAClamp™ were compared for the detection of KRAS mutations using different samples of patients with malignant pleural effusion. PATIENTS AND METHODS: A total of 103 patients (including 56 lung adenocarcinoma, 10 lung squamous carcinoma, 17 small cell lung cancer, 3 large cell lung cancer, 3 stomach cancer, 2 ovarian cancer, and others) with malignant pleural effusion were investigated using matched tumor tissue, cell block, and pleural effusion samples. The diagnostic performance of these two methods was compared. RESULTS: KRAS mutations were detected in 18 (17.5%) of 103 patients using tissue, cell block, and pleural effusion samples. All 18 patients with KRAS mutations were detected by PANAMutyper™ using any sample type, however, only 7 cases were detected by PNAClamp™. Among the subtypes of KRAS mutations, substitution in codon 12, 35G>T was the most frequent, followed by substitution in codon 12, 35G>A and codon 12, 34G>A. In pleural effusion specimens, PANAMutyper™ showed a better diagnostic performance compared to PNAClamp™. CONCLUSION: PANAMutyper™ had a diagnostic superiority for the detection of KRAS mutations in patients with malignant pleural effusion compared to PNAClamp™, although there was a concordance between PANAMutyper™ and PNAClamp™ results. Therefore, PANAMutyper™ can be used for a more sensitive and accurate detection of KRAS mutations.
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Análisis Mutacional de ADN/métodos , Mutación , Derrame Pleural Maligno/diagnóstico , Derrame Pleural Maligno/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Línea Celular Tumoral , Análisis Mutacional de ADN/normas , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y EspecificidadRESUMEN
BACKGROUND/AIM: This study compared the efficacy of PANAMutyper™, a novel technology that integrates PNAClamp™ and PANA S-Melting™, and PNAClamp™ alone for the detection of EGFR mutations in lung cancer patients. MATERIALS AND METHODS: PANAMutyper™ and PNAClamp™ were used to assess the EGFR mutation status in tissue, cell block, pleural effusion, and blood samples of 90 lung cancer patients with malignant pleural effusion. RESULTS: PANAMutyper™ detected more EGFR mutations than PNAClamp™, especially in body fluids (pleural effusion and serum). Patients with additional EGFR mutations detected using PANAMutyper™ had a favorable response to EGFR-tyrosine kinase inhibitor (TKI) treatment. CONCLUSION: The diagnostic performance of PANAMutyper™ was superior to that of PNAClamp™ for the detection of EGFR mutations. It was also better at identifying lung cancer patients with malignant pleural effusion who were likely to benefit from EGFR-TKI treatment.
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Análisis Mutacional de ADN , Neoplasias Pulmonares/genética , Derrame Pleural Maligno/genética , Anciano , Receptores ErbB/genética , Femenino , Congelación , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Mutación , Ácidos Nucleicos de Péptidos/genética , Derrame Pleural Maligno/tratamiento farmacológico , Derrame Pleural Maligno/patología , Inhibidores de Proteínas Quinasas/administración & dosificaciónRESUMEN
BACKGROUND: A hypoxic microenvironment leads to an increase in the invasiveness and the metastatic potential of cancer cells within tumors via the epithelial-mesenchymal transition (EMT) and cancer stemness acquisition. However, hypoxia-induced changes in the expression and function of candidate stem cell markers and their possible molecular mechanism is still not understood. METHODS: Lung cell lines were analyzed in normoxic or hypoxic conditions. For screening among the stem cell markers, a transcriptome analysis using next-generation sequencing was performed. For validation, the EMT and stem cell characteristics were analyzed. To determine whether an epigenetic mechanism was involved, the cell lines were treated with a DNA methyltransferase inhibitor (AZA), and methylation-specific PCR and bisulfite sequencing were performed. RESULTS: Next-generation sequencing revealed that the CXCR4 expression was significantly higher after the hypoxic condition, which functionally resulted in the EMT and cancer stemness acquisition. The acquisition of the EMT and stemness properties was inhibited by treatment with CXCR4 siRNA. The CXCR4 was activated by either the hypoxic condition or treatment with AZA. The methylation-specific PCR and bisulfite sequencing displayed a decreased CXCR4 promoter methylation in the hypoxic condition. CONCLUSIONS: These results suggest that hypoxia-induced acquisition of cancer stem cell characteristics was associated with CXCR4 activation by its aberrant promoter demethylation.
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Hipoxia/inmunología , Neoplasias Pulmonares/inmunología , Pulmón/patología , Células Madre Neoplásicas/fisiología , Receptores CXCR4/metabolismo , Línea Celular Tumoral , Movimiento Celular , Metilación de ADN , Epigénesis Genética , Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Humanos , Invasividad Neoplásica , Metástasis de la Neoplasia , Regiones Promotoras Genéticas , Receptores CXCR4/genética , Transducción de Señal , Microambiente TumoralRESUMEN
Rhodobacter sphaeroides consists of two chromosomes and many plasmids and incorporates many environmentally important functional gene. Rhodobacter sphaeroides MBTLJ-8 was derived from R. sphaeroides 2.4.1 using chemical mutagenesis and is characterized by enhanced production of physiological active compounds as well as improved carbon dioxide reduction capacity. We reported the complete genome sequence and characteristics based on genomic information of this bacteria. Therefore, this genome sequence provides elucidation for improved CO2 fixation and enhanced physiological active compounds production, and will be used as the efficient photosynthetic bacteria for the biological CO2 reduction system.
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Dióxido de Carbono/metabolismo , Genoma Bacteriano , Rhodobacter sphaeroides/genética , Rhodobacter sphaeroides/metabolismo , Oxidación-ReducciónRESUMEN
TAGLN is an actin-binding protein family that comprises three isoforms with theorized roles in smooth muscle differentiation, tumour development, lymphocyte activation, and brain chemistry. However, their fundamental characteristics in regulation of the actin-based cytoskeleton are not fully understood. Here we show that TAGLN2 (including TAGLN1 and TAGLN3) extensively nucleates G-actin polymerization under low-salt conditions, where polymerization would be completely suppressed. The calponin homology domain and actin-binding loop are essential to mechanically connect two adjacent G-actins, thereby mediating multimeric interactions. However, TAGLN2 blocked the Arp2/3 complex binding to actin filaments under physiological salt conditions, thereby inhibiting branched actin nucleation. In HeLa and T cells, TAGLN2 enhanced filopodium-like membrane protrusion. Collectively, the dual functional nature of TAGLN2-G-actin polymerization and Arp2/3 complex inhibition-may account for the mechanisms of filopodia development at the edge of Arp2/3-rich lamellipodia in various cell types.
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Complejo 2-3 Proteico Relacionado con la Actina/metabolismo , Actinas/química , Proteínas de Microfilamentos/metabolismo , Proteínas Musculares/metabolismo , Multimerización de Proteína , Animales , Células HeLa , Humanos , Ratones , Modelos Moleculares , Estructura Cuaternaria de Proteína , Transporte de Proteínas , Seudópodos/metabolismoRESUMEN
Here, we present a facile and low-cost method to produce hierarchically porous graphene-based carbons from a biomass source. Three-dimensional (3D) graphene-based carbons were produced through continuous sequential steps such as the formation and transformation of glucose-based polymers into 3D foam-like structures and their subsequent carbonization to form the corresponding macroporous carbons with thin graphene-based carbon walls of macropores and intersectional carbon skeletons. Physical and chemical activation was then performed on this carbon to create micro- and meso-pores, thereby producing hierarchically porous biomass-derived graphene-based carbons with a high Brunauer-Emmett-Teller specific surface area of 3,657 m2 g-1. Owing to its exceptionally high surface area, interconnected hierarchical pore networks, and a high degree of graphitization, this carbon exhibited a high specific capacitance of 175 F g-1 in ionic liquid electrolyte. A supercapacitor constructed with this carbon yielded a maximum energy density of 74 Wh kg-1 and a maximum power density of 408 kW kg-1, based on the total mass of electrodes, which is comparable to those of the state-of-the-art graphene-based carbons. This approach holds promise for the low-cost and readily scalable production of high performance electrode materials for supercapacitors.
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A hypoxic microenvironment leads to cancer progression and increases the metastatic potential of cancer cells within tumors via epithelial-mesenchymal transition (EMT) and cancer stemness acquisition. The hypoxic response pathway can occur under oxygen tensions of < 40 mmHg through hypoxia-inducible factors (HIFs), which are considered key mediators in the adaptation to hypoxia. Previous studies have shown that cellular responses to hypoxia are required for EMT and cancer stemness maintenance through HIF-1α and HIF-2α. The principal transcription factors of EMT include Twist, Snail, Slug, Sip1 (Smad interacting protein 1), and ZEB1 (zinc finger E-box-binding homeobox 1). HIFs bind to hypoxia response elements within the promoter region of these genes and also target cancer stem cell-associated genes and mediate transcriptional responses to hypoxia during stem cell differentiation. Acquisition of stemness characteristics in epithelial cells can be induced by activation of the EMT process. The mechanism of these phenotypic changes includes epigenetic alterations, such as DNA methylation, histone modification, chromatin remodeling, and microRNAs. Increased expression of EMT and pluripotent genes also play a role through demethylation of their promoters. In this review, we summarize the role of hypoxia on the acquisition of EMT and cancer stemness and the possible association with epigenetic regulation, as well as their therapeutic applications.