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Salmonella translocate to the gut epithelium via microfold cells lining the follicle-associated epithelium (FAE). How Salmonella localize to the FAE is not well characterized. Here we use live imaging and competitive assays between wild-type and chemotaxis-deficient mutants to show that Salmonella enterica serotype Typhimurium (S. Typhimurium) localize to the FAE independently of chemotaxis in an ex vivo mouse caecum infection model. Electrical recordings revealed polarized FAE with sustained outward current and small transepithelial potential, while the surrounding villus is depolarized with inward current and large transepithelial potential. The distinct electrical potentials attracted S. Typhimurium to the FAE while Escherichia coli (E. coli) localized to the villi, through a process called galvanotaxis. Chloride flux involving the cystic fibrosis transmembrane conductance regulator (CFTR) generated the ionic currents around the FAE. Pharmacological inhibition of CFTR decreased S. Typhimurium FAE localization but increased E. coli recruitment. Altogether, our findings demonstrate that bioelectric cues contribute to S. Typhimurium targeting of specific gut epithelial locations, with potential implications for other enteric bacterial infections.
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BACKGROUND: The incidence of early-stage lung adenocarcinoma (ES-LUAD) is steadily increasing among non-smokers. Previous research has identified dysbiosis in the gut microbiota of patients with lung cancer. However, the local microbial profile of non-smokers with ES-LUAD remains largely unknown. In this study, we systematically characterized the local microbial community and its associated features to enable early intervention. METHODS: A prospective collection of ES-LUAD samples (46 cases) and their corresponding normal tissues adjacent to the tumor (41 cases), along with normal lung tissue samples adjacent to pulmonary bullae in patients with spontaneous pneumothorax (42 cases), were subjected to ultra-deep metagenomic sequencing, host transcriptomic sequencing, and proteomic sequencing. The obtained omics data were subjected to both individual and integrated analysis using Spearman correlation coefficients. RESULTS: We concurrently detected the presence of bacteria, fungi, and viruses in the lung tissues. The microbial profile of ES-LUAD exhibited similarities to NAT but demonstrated significant differences from the healthy controls (HCs), characterized by an overall reduction in species diversity. Patients with ES-LUAD exhibited local microbial dysbiosis, suggesting the potential pathogenicity of certain microbial species. Through multi-omics correlations, intricate local crosstalk between the host and local microbial communities was observed. Additionally, we identified a significant positive correlation (rho > 0.6) between Methyloversatilis discipulorum and GOLM1 at both the transcriptional and protein levels using multi-omics data. This correlated axis may be associated with prognosis. Finally, a diagnostic model composed of six bacterial markers successfully achieved precise differentiation between patients with ES-LUAD and HCs. CONCLUSIONS: Our study depicts the microbial spectrum in patients with ES-LUAD and provides evidence of alterations in lung microbiota and their interplay with the host, enhancing comprehension of the pathogenic mechanisms that underlie ES-LUAD. The specific model incorporating lung microbiota can serve as a potential diagnostic tool for distinguishing between ES-LUAD and HCs.
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Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Metagenómica , Microbiota , Proteómica , Transcriptoma , Humanos , Adenocarcinoma del Pulmón/microbiología , Adenocarcinoma del Pulmón/genética , Neoplasias Pulmonares/microbiología , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Metagenómica/métodos , Masculino , Femenino , Transcriptoma/genética , Microbiota/genética , Persona de Mediana Edad , Estadificación de Neoplasias , Disbiosis/microbiología , Perfilación de la Expresión Génica , Interacciones Microbiota-Huesped/genética , AncianoRESUMEN
Electrical signaling plays a crucial role in the cellular response to tissue injury in wound healing and an external electric field (EF) may expedite the healing process. Here, we have developed a standalone, wearable, and programmable electronic device to administer a well-controlled exogenous EF, aiming to accelerate wound healing in an in vivo mouse model to provide pre-clinical evidence. We monitored the healing process by assessing the re-epithelization rate and the ratio of M1/M2 macrophage phenotypes through histology staining. Following three days of treatment, the M1/M2 macrophage ratio decreased by 30.6% and the re-epithelization in the EF-treated wounds trended towards a non-statically significant 24.2% increase compared to the control. These findings provide point towards the effectiveness of the device in shortening the inflammatory phase by promoting reparative macrophages over inflammatory macrophages, and in speeding up re-epithelialization. Our wearable device supports the rationale for the application of programmed EFs for wound management in vivo and provides an exciting basis for further development of our technology based on the modulation of macrophages and inflammation to better wound healing.
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Modelos Animales de Enfermedad , Inflamación , Macrófagos , Cicatrización de Heridas , Animales , Ratones , Inflamación/terapia , Inflamación/patología , Masculino , Dispositivos Electrónicos VestiblesRESUMEN
We propose a low loss, wideband silicon transverse magnetic (TM) polarizer with high polarization extinction ratio and low reflection based on subwavelength grating. By arranging and optimizing a mutually perpendicular subwavelength grating with different duty cycles as the core and cladding, efficient waveguiding and radiation can be achieved for the TM and transverse electric (TE) injection, respectively. In simulation, the proposed TM polarizer has a footprint of 40µm×16.68µm, an insertion loss <0.7d B, a polarization extinction ratio ≥20d B, and an unwanted TE reflection <-17.4d B in the wavelength range of 1230-1700 nm. Moreover, the fabrication tolerance of the proposed device is also investigated.
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Betaine-homocysteine methyltransferase (BHMT) regulates protein methylation and is correlated with tumorigenesis; however, the effects and regulation of BHMT in hepatocarcinogenesis remain largely unexplored. Here, we determined the clinical significance of BHMT in the occurrence and progression of hepatocellular carcinoma (HCC) using tissue samples from 198 patients. BHMT was to be frequently found (86.6%) expressed at relatively low levels in HCC tissues and was positively correlated with the overall survival of patients with HCC. Bhmt overexpression effectively suppressed several malignant phenotypes in hepatoma cells in vitro and in vivo, whereas complete knockout of Bhmt (Bhmt-/-) produced the opposite effect. We combined proteomics, metabolomics, and molecular biological strategies and detected that Bhmt-/- promoted hepatocarcinogenesis and tumor progression by enhancing the activity of glucose-6-phosphate dehydrogenase (G6PD) and PPP metabolism in DEN-induced HCC mouse and subcutaneous tumor-bearing models. In contrast, restoration of Bhmt with an AAV8-Bhmt injection or pharmacological inhibition of G6PD attenuated hepatocarcinogenesis. Additionally, coimmunoprecipitation identified monomethylated modifications of the G6PD, and BHMT regulated the methylation of G6PD. Protein sequence analysis, generation and application of specific antibodies, and site-directed mutagenesis indicated G6PD methylation at the arginine residue 246. Furthermore, we established bidirectionally regulated BHMT cellular models combined with methylation-deficient G6PD mutants to demonstrate that BHMT potentiated arginine methylation of G6PD, thereby inhibiting G6PD activity, which in turn suppressed hepatocarcinogenesis. Taken together, this study reveals a new methylation-regulatory mechanism in hepatocarcinogenesis owing to BHMT deficiency, suggesting a potential therapeutic strategy for HCC treatment.
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Betaína-Homocisteína S-Metiltransferasa , Carcinogénesis , Carcinoma Hepatocelular , Glucosafosfato Deshidrogenasa , Neoplasias Hepáticas , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Animales , Humanos , Metilación , Betaína-Homocisteína S-Metiltransferasa/metabolismo , Betaína-Homocisteína S-Metiltransferasa/genética , Glucosafosfato Deshidrogenasa/metabolismo , Glucosafosfato Deshidrogenasa/genética , Ratones , Carcinogénesis/genética , Carcinogénesis/metabolismo , Arginina/metabolismo , Masculino , Línea Celular Tumoral , Ratones Noqueados , Regulación Neoplásica de la Expresión GénicaRESUMEN
Potential systemic factors contributing to aging-associated breast cancer (BC) remain elusive. Here, we reveal that the polyploid giant cells (PGCs) that contain more than two sets of genomes prevailing in aging and cancerous tissues constitute 5-10% of healthy female bone marrow mesenchymal stromal cells (fBMSCs). The PGCs can repair DNA damage and stimulate neighboring cells for clonal expansion. However, dying PGCs in advanced-senescent fBMSCs can form "spikings" which are then separated into membraned mtDNA-containing vesicles (Senescent PGC-Spiking Bodies; SPSBs). SPSB-phagocytosed macrophages accelerate aging with diminished clearance on BC cells and protumor M2 polarization. SPSB-carried mitochondrial OXPHOS components are enriched in BC of elder patients and associated with poor prognosis. SPSB-incorporated breast epithelial cells develop aggressive characteristics and PGCs resembling the polyploid giant cancer cells (PGCCs) in clonogenic BC cells and cancer tissues. These findings highlight an aging BMSC-induced BC risk mediated by SPSB-induced macrophage dysfunction and epithelial cell precancerous transition. SIGNIFICANCE: Mechanisms underlying aging-associated cancer risk remain unelucidated. This work demonstrates that polyploid giant cells (PGCs) in bone marrow mesenchymal stromal cells (BMSCs) from healthy female bone marrow donors can boost neighboring cell proliferation for clonal expansion. However, the dying-senescent PGCs in the advanced-senescent fBMSCs can form "spikings" which are separated into mitochondrial DNA (mtDNA)-containing spiking bodies (senescent PGC-spiking bodies; SPSBs). The SPSBs promote macrophage aging and breast epithelial cell protumorigenic transition and form polyploid giant cancer cells. These results demonstrate a new form of ghost message from dying-senescent BMSCs, that may serve as a systemic factor contributing to aging-associated immunosuppression and breast cancer risk.
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Macrophages can exhibit pro-inflammatory or pro-reparatory functions, contingent upon their specific activation state. This dynamic behavior empowers macrophages to engage in immune reactions and contribute to tissue homeostasis. Understanding the intricate interplay between macrophage motility and activation status provides valuable insights into the complex mechanisms that govern their diverse functions. In a recent study, we developed a classification method based on morphology, which demonstrated that movement characteristics, including speed and displacement, can serve as distinguishing factors for macrophage subtypes. In this study, we develop a deep learning model to explore the potential of classifying macrophage subtypes based solely on raw trajectory patterns. The classification model relies on the time series of x-y coordinates, as well as the distance traveled and net displacement. We begin by investigating the migratory patterns of macrophages to gain a deeper understanding of their behavior. Although this analysis does not directly inform the deep learning model, it serves to highlight the intricate and distinct dynamics exhibited by different macrophage subtypes, which cannot be easily captured by a finite set of motility metrics. Our study uses cell trajectories to classify three macrophage subtypes: M0, M1, and M2. This advancement holds promising implications for the future, as it suggests the possibility of identifying macrophage subtypes without relying on shape analysis. Consequently, it could potentially eliminate the necessity for high-quality imaging techniques and provide more robust methods for analyzing inherently blurry images.
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Arachidonic acid metabolism plays a crucial role in the development and progression of inflammatory and metabolic liver diseases. However, its role in hepatocellular carcinoma (HCC) remains unclear. In this study, we investigated the expression of key genes involved in the arachidonic acid metabolism pathway in HCC using a combination of bioinformatics, proteomics and immunohistochemistry analyses. Through a comprehensive analysis of publicly available datasets, clinical HCC tissues, and tissue microarrays, we compared the expression of hepatic arachidonic acid metabolic genes. We observed significant downregulation of cytochrome P450 (CYP450) pathway genes at both the messenger RNA and protein levels in HCC tissues compared to normal liver tissues. Furthermore, we observed a strong correlation between the deregulation of the arachidonic acid metabolism CYP450 pathway and the pathological features and prognosis of HCC. Specifically, the expression of CYP2C8/9/18/19 was significantly correlated with pathological grade (r = -.484, p < .0001), vascular invasion (r = -.402, p < .0001), aspartate transaminase (r = -.246, p = .025), gamma-glutamyl transpeptidase (r = -.252, p = .022), alkaline phosphatase (r = -.342, p = .002), alpha-fetoprotein (r = -.311, p = .004) and carbohydrate antigen 19-9 (r = -.227, p = .047). Moreover, we discovered a significant association between CYP450 pathway activity and vascular invasion in HCC. Collectively, these data indicate that arachidonic acid CYP450 metabolic pathway deregulation is implicated in HCC progression and may be a potential predictive factor for early recurrence in patients with HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Ácido Araquidónico , Sistema Enzimático del Citocromo P-450/genéticaRESUMEN
The composite material-like extracellular matrix (ECM) in the sinoatrial node (SAN) supports the native pacemaking cardiomyocytes (PCMs). To test the roles of SAN ECM in the PCM phenotype and function, we engineered reconstructed-SAN heart tissues (rSANHTs) by recellularizing porcine SAN ECMs with hiPSC-derived PCMs. The hiPSC-PCMs in rSANHTs self-organized into clusters resembling the native SAN and displayed higher expression of pacemaker-specific genes and a faster automaticity compared with PCMs in reconstructed-left ventricular heart tissues (rLVHTs). To test the protective nature of SAN ECMs under strain, rSANHTs and rLVHTs were transplanted onto the murine thoracic diaphragm to undergo constant cyclic strain. All strained-rSANHTs preserved automaticity, whereas 66% of strained-rLVHTs lost their automaticity. In contrast to the strained-rLVHTs, PCMs in strained-rSANHTs maintained high expression of key pacemaker genes (HCN4, TBX3, and TBX18). These findings highlight the promotive and protective roles of the composite SAN ECM and provide valuable insights for pacemaking tissue engineering.
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Miocitos Cardíacos , Nodo Sinoatrial , Ratones , Animales , Porcinos , Miocitos Cardíacos/metabolismo , Ventrículos Cardíacos , FenotipoRESUMEN
This paper presents the first investigation of the adsorption performance of methylene blue by the nitro-functionalized metal-organic framework (MIL-88B-NO2). MIL-88B-NO2 has a specific surface area of 836.0 m2/g, which is 109.8 % higher than MIL-88B. The maximum adsorption capacity of methylene blue is 383.6 mg/g, which is 68.2 % higher than that of MIL-88B. This phenomenon can be attributed to the great increase in specific surface area and the introduction of nitro-functional groups. However, its microcrystalline nature makes it difficult to remove in practical applications and quickly causes secondary pollution. Therefore, the composite of MIL-88B-NO2 and calcium alginate (CA) to form aerogel maintains the inherent properties of the two materials and makes it easy to recycle. The utmost adsorption capability of MIL-88B-NO2/CA-2 aerogel is 721.0 mg/g. Compared with MIL-88B-NO2, the adsorption performance of MIL-88B-NO2/CA-2 aerogel is further improved by 88.0 %. The higher adsorption capacity of the adsorbent may be due to the synergistic interplay of electrostatic attraction, π-π conjugation, hydrogen bonding, metal coordination effect, and physicochemical properties. Also, MIL-88B-NO2/CA-2 aerogel has good recyclability, indicating that it has broad application prospects in the removal of positive dyes in contaminated water.
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Azul de Metileno , Agua , Adsorción , Agua/química , Dióxido de Nitrógeno , Metales , Radiofármacos , EsqueletoRESUMEN
Micro-nano metal-organic framework (MIL-68(Fe)) for efficient adsorption of azo anionic dye Congo red (CR) was successfully prepared by one-step hydrothermal method under acidic environment. And a MIL-68(Fe)/chitosan composite sponge (MIL-68(Fe)/CS) was prepared under the coating of chitosan (CS). After comparing the performance of MIL-68(Fe) and MIL-68(Fe)/CS, we focus on exploring MIL-68(Fe)/CS. It ensured the CR removal efficiency while reaching the adsorption equilibrium faster than MIL-68(Fe), and solved the defect that the powder was difficult to be stripped by water after adsorption. The physicochemical properties and surface morphology of the adsorbent were characterized by SEM, FTIR, XRD, TGA, BET, and Zeta potential. The effects of pH, contact time, adsorbent dosage, initial solution concentration and temperature on the adsorption performance of the adsorbent were systematically analyzed. The pseudo-second-order model and the Sips model were most consistent for the adsorption process, indicating that the adsorption process of MIL-68(Fe)/chitosan composite sponge on CR is a complex physicochemical process. The removal rates of CR by MIL-68(Fe) and MIL-68(Fe)/chitosan composite sponge reached the maximum values of 99.55 % and 99.51 % at 318 K, respectively. And the maximum adsorption capacity of CR by MIL-68(Fe)/chitosan composite sponge at 318 K was 1184.16 mg·g-1. After six cycles of adsorption and desorption, the removal rate of CR was still higher than 80 %. The synergistic effects of π-π stacking, electrostatic interactions, hydrogen bonding and pore filling have important effects on CR removal.
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Quitosano , Estructuras Metalorgánicas , Contaminantes Químicos del Agua , Rojo Congo , Quitosano/química , Adsorción , Compuestos Azo , Contaminantes Químicos del Agua/química , Cinética , Concentración de Iones de HidrógenoRESUMEN
In this paper, the physicochemical properties, surface charge, and crystal defects of MIL-88A (Al) were controlled by adjusting the ratio of metal ligands and temperature in the synthetic system without the addition of surfactants. The adsorption properties of different crystals for Congo red (CR) were studied. Among them, MIL-88A (Al)-130 and MIL-88A (Al)-d have the best adsorption properties. The maximum adsorption capacities are 600.8 and 1167 mg · g-1, respectively. Compared with MIL-88A (Al)-130, the adsorption performance of MIL-88A (Al)-d was increased by 94.2%, and the adsorption rate was increased by about 4 times. It can be seen that increasing the proportion of metal ligands within a certain range will improve the adsorption capacity. The structure and morphology of the adsorbent were characterized by XRD, FTIR, SEM, EDS, TGA, BET, and zeta potential. The effects of time, temperature, pH, initial solution concentration, and dosage on CR adsorption properties were systematically discussed. The pseudo-second-order kinetic model and Langmuir isothermal model can well describe the adsorption process, which indicates that the adsorption process is a single-layer chemisorption occurring on a uniform surface. According to thermodynamics, this adsorption is an endothermic process. The mechanism of CR removal is proposed as the electrostatic attraction, hydrogen bond, metal coordination effect, π-π conjugation, crystal defect, and pore-filling effect. In addition, MIL-88A (Al)-d has good repeatability, indicating that it is a good material for treating anionic dye wastewater.
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Here, we present a protocol for electrotaxis of large epithelial cell sheets without compromising the integrity of cell epithelia in a high-throughput customized directed current electrotaxis chamber. We describe the fabrication and use of polydimethylsiloxane stencils to control the size and shape of human keratinocyte cell sheets. We detail cell tracking, cell sheet contour assay, and particle image velocimetry to reveal the spatial and temporal motility dynamics of cell sheets. This approach is applicable to other collective cell migration studies. For complete details on the use and execution of this protocol, please refer to Zhang et al. (2022).1.
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A chitosan/alginate/graphene oxide/UiO-67 (CS/SA/GO/UiO-67) amphoteric aerogel was synthesized successfully. A series of characterization experiments of CS/SA/GO/UiO-67 amphoteric aerogel was performed by SEM, EDS, FT-IR, TGA, XRD, BET, and zeta potential. The competitive adsorption properties of different adsorbents for complex dyes wastewater (MB and CR) at room temperature (298 K) were compared. Langmuir isotherm model predicted that the maximum adsorption quantity of CS/SA/GO/UiO-67 for CR and MB was 1091.61 and 1313.95 mg/g, respectively. The optimum pH values of CS/SA/GO/UiO-67 for the adsorption of CR and MB were 5 and 10, respectively. The kinetic analysis showed that the adsorption of MB and CR on CS/SA/GO/UiO-67 was more suitable for the pseudo-second-order and pseudo-first-order kinetic model, respectively. The isotherm study revealed that the adsorption of MB and CR was consistent with the Langmuir isotherm model. The thermodynamic study demonstrated that the adsorption process of MB and CR was exothermic and spontaneous. FT-IR analysis and zeta potential characterization experiments revealed that the adsorption mechanism of MB and CR on CS/SA/GO/UiO-67 depended on π-π bond, hydrogen bond, and electrostatic attraction. Repeatable experiments showed that the removal rates of MB and CR of CS/SA/GO/UiO-67 after six cycles of adsorption were 67.19 and 60.82 %, respectively.
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Quitosano , Colorantes , Colorantes/química , Quitosano/química , Espectroscopía Infrarroja por Transformada de Fourier , Adsorción , Alginatos , CinéticaRESUMEN
Abnormal cholesterol synthesis plays a crucial role in the development of hepatocellular carcinoma (HCC). Sterol regulatory element-binding protein 2 (SREBP2) is involved in cholesterol synthesis by translocating to the nucleus where it stimulates the transcription of genes encoding enzymes involved in the cholesterol synthesis pathway. However, the function and regulatory mechanism of SREBP2 in HCC remain unclear. In this study, we aimed to gain a better understanding of the effects of SREBP2 and its functional mechanism in HCC. In 20 HCC patients, we demonstrated that SREBP2 was highly expressed in HCC specimens, relative to their peritumoral tissue, and that higher expression correlated positively with a poor prognosis in these patients. Moreover, higher SREBP2 levels in the nucleus enhanced the occurrence of microvascular invasion, whereas inhibition of SREBP2 nuclear translocation by fatostatin markedly suppressed the migration and invasion of HCC cells via the epithelial-mesenchymal transition (EMT) process. The effects of SREBP2 were subject to functional activity of large tumor suppressor kinase (LATS), whereas inhibition of LATS promoted nuclear translocation of SREBP2, as observed in hepatoma cells and a subset of subcutaneous tumor samples from nude mice. In conclusion, SREBP2 enhances the invasion and metastasis of HCC cells by promoting EMT, which can be strengthened by the repression of LATS. Therefore, SREBP2 may serve as a novel therapeutic target for HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Ratones , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/patología , Ratones Desnudos , HumanosRESUMEN
Zirconium alginate/graphene oxide (ZA/GO) hydrogel spheres were prepared by crosslinking sodium alginate and GO with Zr4+. Then Zr4+ on the surface of the ZA/GO substrate acted as the metal nucleation site of the UiO-67 crystal and interacted with the organic ligand biphenyl 4-4'-dicarboxylic acid (BPDC) to make UiO-67 grow in situ on the surface of the ZA/GO hydrogel sphere by the hydrothermal method. The BET surface areas of ZA/GO, ZA/UiO-67, and ZA/GO/UiO-67 aerogel spheres were 1.29, 47.71, and 89.33 m2/g respectively. The maximum adsorption capacities of ZA/GO, ZA/UiO-67, and ZA/GO/UiO-67 aerogel spheres for methylene blue (MB) at room temperature (298 K) were 145.08, 307.49, and 1105.23 mg/g respectively. The kinetic analysis showed that the adsorption process of MB on the ZA/GO/UiO-67 aerogel sphere was consistent with the pseudo-first-order kinetic model. Isotherm analysis showed that MB was adsorbed on ZA/GO/UiO-67 aerogel spheres as a single layer. Thermodynamic analysis showed that the adsorption process of MB on the ZA/GO/UiO-67 aerogel sphere was exothermic and spontaneous. Adsorption of MB on ZA/GO/UiO-67 aerogel spheres is mainly dependent on π-π bond, electrostatic interaction, and hydrogen bond. After 8 cycles, ZA/GO/UiO-67 aerogel spheres still showed high adsorption performance and good reuse ability.
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Grafito , Contaminantes Químicos del Agua , Azul de Metileno/química , Cinética , Adsorción , Alginatos/química , Contaminantes Químicos del Agua/química , Grafito/química , HidrogelesRESUMEN
MIL-88A crystals with three different metal ligands (Fe, Al, FeAl) were prepared by hydrothermal method for the first time. The three materials' crystal structure and surface morphology are different, leading to different adsorption properties of Congo red (CR). The maximum adsorption capacities of MIL-88A (Fe), MIL-88A (FeAl), and MIL-88A (Al) are 607.7 mg · g-1, 536.4 mg · g-1, and 512.1 mg · g-1 respectively. In addition, MIL-88A was combined with chitosan (CS) respectively, and MIL-88A/CS composite sponge was prepared by the freeze-drying method, which not only solved the defect that MIL-88A powder was difficult to recover but also further improved the removal ability of CR by the adsorbent. The maximum adsorption capacities of MIL-88A (FeAl)/CS, MIL-88A (Fe)/CS, MIL-88A (Al)/CS, and CS are 1312 mg · g-1, 1056 mg · g-1, 996.7 mg · g-1, and 769.6 mg · g-1, respectively. The structure and physicochemical properties of the materials were analyzed by SEM, FTIR, XRD, TGA, BET, and Zeta. The adsorption process of CR follows pseudo-second-order kinetics and Langmuir, Sips isotherm model. Combined with thermodynamic parameters, the adsorption behavior was described as endothermic monomolecular chemical adsorption. The removal of CR is attributed to electrostatic interactions, hydrogen bonding, metal coordination effects, and size-matching effects.
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Quitosano , Contaminantes Químicos del Agua , Rojo Congo , Quitosano/química , Adsorción , Termodinámica , Contaminantes Químicos del Agua/química , CinéticaRESUMEN
Recent research has elucidated mechanochemical pathways of single cell polarization, but much less is known about collective motility initiation in adhesive cell groups. We used galvanotactic assays of zebrafish keratocyte cell groups, pharmacological perturbations, electric field switches, particle imaging velocimetry, and cell tracking to show that large cell groups initiate motility in minutes toward the cathode. Interestingly, while PI3K-inhibited single cells are biased toward the anode, inhibiting PI3K does not affect the cathode-directed cell group migration. We observed that control groups had the fastest cathode-migrating cell at the front, while the front cells in PI3K-inhibited groups were the slowest. Both control and PI3K-inhibited groups rapidly repolarized when the electric field direction was reversed, and the group migration continued after the electric field was switched off. Inhibiting myosin disrupted the cohesiveness of keratocyte groups and abolished the collective directionality and ability to switch direction when the electric field is reversed. Our data are consistent with a model according to which cells in the group sense the electric field individually and mechanical integration of the cells results in coherent group motility.
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Fosfatidilinositol 3-Quinasas , Pez Cebra , Animales , Movimiento CelularRESUMEN
In this study, composite hydrogels were prepared using a simple synthetic technique to adsorb methylene blue (MB) from water. The hydrogel comprised potassium persulfate (KPS) as the initiator, N,N'-methylene bisacrylamide as the crosslinking agent, and sodium hydroxide (NaOH) as the activator. It was employed to adsorb MB at different concentrations from water. The morphology and properties of PUL/PAM/GO composites were characterized through thermogravimetric analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. Moreover, the adsorption properties, adsorption isotherms, adsorption kinetics, adsorption thermodynamics, and swelling properties of the hydrogel for MB were investigated. The optimal ratio of PUL to AC was obtained as 6:1 by fixing the amount of PUL and loading AC of different masses. The maximum adsorption capacity was obtained as 591.4 mg/g. It also exhibited certain mechanical strength. The adsorption of MB conforms to pseudo-first-order kinetics and Langmuir isotherms. In this study, an environment-friendly, cheap, simple, and efficient way was presented for the composite hydrogel in the direction of water treatment.
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To reduce the filling cost of high-water backfilling material (HWBM) in mining backfill and improve the recycling utilization of the industrial waste such as the coal fly ash. The ultra-fine fly ash (UFA) was added to the HWBM as a partial replacement in this work. Therefore, a series of experiments were performed to investigate the effect of UFA on the mechanical properties of the HWBM at the different curing conditions, then the hydration mechanism of the HWBM blended with UFA was analyzed by XRD and SEM method. The result indicates that the strength of the HWBM decreased with the increasing of UFA dosages, but the addition of UFA can improve the residual strength of the initial HWBM. Additionally, when the HWBM was cured at the laboratory air condition, its carbonation process was restrained obviously as the UFA dosages were less than 15% at the ages of 28 days, which indicates the UFA can improve the weathering resistance of the HWBM with the curing ages increasing effectively. The XRD and SEM results also shows that the degree of crystallinity of the HWBM increased when UFA dosages were less than 15% effectively, while there were few obvious changes on types of hydration products. It indicates that the main affects of UFA on the performance of HWBM is filler and dilution, which reduced the contact area between hydration products of HWBM and CO2 in the air, further improved the carbonation resistance of HWBM.