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A novel thermoreversible emulsion gel was successfully prepared with citrate agar (CA) as the sole emulsifier. Compared with native agar gel emulsion, CA gel emulsion (CAGE) formed a stable emulsion gel when the CA concentration was increased to 1.25 % (w/w). Results of time-temperature scanning experiments showed that the emulsion gel rapidly transformed into liquid emulsion when heated to 40-50 °C and then solidified into emulsion gel after cooling to the critical temperature of solidification. The emulsion gel had stable sol-gel transformation ability after seven cycles repeated heating-cooling treatment (HCT) at 85 °C and 4 °C. However, the stability of emulsion gels gradually decreased because of the large-droplet formation during heating, which affected the CA molecular-reconfiguration network structure in cooling. The conjunction analysis of microstructure and properties of the emulsion gel indicated that its stability depended primarily on the spatial repulsion and electrostatic repulsion provided by CA gel, and the main factor driving thermal reversibility was the temperature-responsive gelation performance of CA. The retention of quercetin was >90.23 % after seven HCTs because CAGEG enhanced the homogeneity and stability of the droplets.
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Agar , Emulsiones , Geles , Temperatura , Agar/química , Emulsiones/química , Geles/química , Ácido Cítrico/química , Quercetina/químicaRESUMEN
Objective: This cross-sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID-19 in China. Methods: This study was conducted by 45 tertiary Grade-A hospitals in China. Online and offline questionnaire data were obtained from patients infected with COVID-19 between December 28, 2022, and February 21, 2023. The collected information included basic demographics, medical history, smoking and drinking history, vaccination history, changes in olfactory and gustatory functions before and after infection, and other postinfection symptoms, as well as the duration and improvement status of olfactory and gustatory disorders. Results: Complete questionnaires were obtained from 35,566 subjects. The overall incidence of olfactory and taste dysfunction was 67.75%. Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste dysfunction. Having received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such dysfunction. Before infection, the average olfactory and taste VAS scores were 8.41 and 8.51, respectively; after infection, they decreased to 3.69 and 4.29 and recovered to 5.83 and 6.55 by the time of the survey. The median duration of dysosmia and dysgeusia was 15 and 12 days, respectively, with 0.5% of patients having symptoms lasting for more than 28 days. The overall self-reported improvement rate was 59.16%. Recovery was higher in males, never smokers, those who received two or three vaccine doses, and those that had never experienced dental health issues, or chronic accompanying symptoms. Conclusions: The incidence of dysosmia and dysgeusia following infection with the SARS-CoV-2 virus is high in China. Incidence and prognosis are influenced by several factors, including sex, SARS-CoV-2 vaccination, history of head-facial trauma, nasal and oral health status, smoking and drinking history, and the persistence of accompanying symptoms.
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In this study, citric acid successfully reacted with agar through the dry heat method, and citrate agar (CA) gel was used to stabilize O/W emulsions. The mechanisms of the CA structure and emulsion pH that affected emulsion stabilization were analyzed, and the application of CA gel emulsion (CAGE) was explored. Compared with native agar (NA), CA showed lower gel strength, higher transparency, and higher water contact angle. These changes indicate that a cross-linking reaction occurred, and it was demonstrated via FTIR and NMR. The emulsion properties were evaluated using particle size, ζ-potential, and the emulsification activity index. Results showed that CAGEs had a smaller particle size and lower ζ-potential than the native agar gel emulsion (NAGE). Meanwhile, confocal laser scanning microscopy confirmed that the CA gels stabilized the emulsions by forming a protective film around the oil droplets. Stability experiments revealed that CAGE (prepared with CA gel [DS = 0.145]) exhibited better stability than NAGE in the pH range of 3-11, and the rheological results further confirmed that the stability of the emulsions was influenced by the network structure and oil droplet interaction forces. Afterward, the application prospect of CAGE was evaluated by encapsulating vitamin D3 and curcumin.
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Agar , Ácido Cítrico , Emulsiones , Tamaño de la Partícula , Emulsiones/química , Agar/química , Ácido Cítrico/química , Concentración de Iones de Hidrógeno , Geles/química , Reología , Agua/química , Colecalciferol/químicaRESUMEN
A new type of core-shell microsphere was prepared by a pre-crosslinking method, consisting of cross-linked agarose microspheres as the core and agarose-dextran as the shell. After optimizing the preparation process, the microspheres with a uniform particle size were obtained and characterized using cryo-scanning electron microscopy to determine their surface and cross-sectional morphology. Results from flow rate-pressure and chromatographic performance tests showed that the core-shell agarose microspheres were supported by the core microspheres and composed of composite polysaccharides, forming an interpenetrating polymer network structure as a hard shell. The core-shell agarose microspheres showed a 300.5 % increase in linear flow rate compared to composite polysaccharide microspheres prepared from shell materials and a 141.5 % increase compared to 6 % agarose microspheres. Additionally, the large pore structure of the shell combined with the fine pore structure of the core improved the material separation efficiency in the range of 0.1-2000 kDa. These findings suggest that core-shell natural polysaccharide microspheres have great potential as a separation chromatographic medium.
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Dextranos , Microesferas , Sefarosa , Estudios Transversales , Microscopía Electrónica de RastreoRESUMEN
Prunin of desirable bioactivity and bioavailability can be transformed from plant-derived naringin by the key enzyme α-L-rhamnosidase. However, the production was limited by unsatisfactory properties of α-L-rhamnosidase such as thermostability and organic solvent tolerance. In this study, biochemical characteristics, and hydrolysis capacity of a novel α-L-rhamnosidase from Spirochaeta thermophila (St-Rha) were investigated, which was the first characterized α-L-rhamnosidase for Spirochaeta genus. St-Rha showed a higher substrate specificity towards naringin and exhibited excellent thermostability and methanol tolerance. The Km of St-Rha in the methanol cosolvent system was decreased 7.2-fold comparing that in the aqueous phase system, while kcat/Km value of St-Rha was enhanced 9.3-fold. Meanwhile, a preliminary conformational study was implemented through comparative molecular dynamics simulation analysis to explore the mechanism underlying the methanol tolerance of St-Rha for the first time. Furthermore, the catalytic ability of St-Rha for prunin preparation in the 20% methanol cosolvent system was explored, and 200 g/L naringin was transformed into 125.5 g/L prunin for 24 h reaction with a corresponding space-time yield of 5.2 g/L/h. These results indicated that St-Rha was a novel α-L-rhamnosidase suitable for hydrolyzing naringin in the methanol cosolvent system and provided a better alternative for improving the efficient production yield of prunin.
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Florizina/análogos & derivados , Spirochaeta , Metanol , Glicósido Hidrolasas/química , SolventesRESUMEN
OBJECTIVE: To explore the effects of Draf1-3 on frontal sinus airflow and frontal sinus irrigation in people with different frontal sinus development METHODS: The development of the frontal sinus and the distribution of the frontal recess cells were evaluated by CT scan in 150 adults (300 sides). The airflow changes into the frontal sinus and frontal recess after Draf were analyzed by Fluent software under a steady state and quiet inspiratory state. Nasal irrigation after Draf in adults with well-developed frontal sinus was simulated using 120 mL saline at a rate of 12 mL/s in a position at 45° to observe the changes in transient flow distribution. RESULTS: The moderately developed type of the frontal sinus was the most common. The airflow patterns in the frontal sinus and frontal recess in the moderate development group were laminar, while several large vortexes were formed between the frontal sinus and frontal recess in the well-development group. The Draf exerted more significant effects on the patterns, pressure, and velocity of the airflow in the frontal sinus and frontal recess in the well development group than in the moderate development group. The volume fraction of saline in the frontal sinus increased significantly from Draf1 to Draf3, and the time required for a complete infiltration of saline in the frontal sinus mucosa was significantly reduced. CONCLUSIONS: Draf1-3 has different effects on the airflow field of the frontal sinus with different developmental types; and Draf1-3 can significantly improve the postoperative flushing of the frontal sinus.
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Seno Frontal , Adulto , Humanos , Seno Frontal/diagnóstico por imagen , Seno Frontal/cirugía , Hidrodinámica , Simulación por Computador , Tomografía Computarizada por Rayos X , Lavado Nasal (Proceso) , EndoscopíaRESUMEN
Objective:To investigate the efficacy of functional endoscopic sinus surgeryï¼FESSï¼ in the treatment of olfactory dysfunction in patients with chronic rhinosinusitis with nasal polyps ï¼CRSwNPï¼ , at the same time, it provides an evidence for the prognosis evaluation of olfaction and the clinical application of oERPs to evaluate the plasticity of olfaction cortex. Methods:From October 2021 to October 2022, 45 patients with CRSwNP who underwent FESS nine-step standardized treatment in our department were recruited as the research subjects, divided into 22 patients with eosinophilic CRSwNPï¼ECRSï¼and 23 patients with non-eosinophilic CRSwNPï¼nECRSï¼. VAS-olfactory dysfunction ï¼VAS-ODï¼ score, SNOT-22 olfactory score, Sniffin' Sticks test and oERPs collection and processing were performed before the operation. All items were evaluated again 3 months after the operation. Results:VAS-OD and SNOT-22 olfactory score were significantly lower in all CRSwNP patients after the operation than those before the operation[Fï¼1, 43ï¼ =357.429, P<0.001; Fï¼1, 43ï¼ =185.657, P<0.001], the scores of T, D, I and TDI scores in Sniffin' Sticks test were significantly higher than those before the operation[Fï¼1, 43ï¼ =126.302, P<0.001; Fï¼1, 43ï¼ =311.301, P<0.001; Fï¼1, 43ï¼ =131.401, P<0.001; Fï¼1, 43ï¼ =295.885, P<0.001]; The decrease of VAS-OD and SNOT-22 olfactory score in the ECRS group was smaller than that in the nECRS group[Fï¼1, 43ï¼ =4.825, P=0.033; Fï¼1, 43ï¼ =9.916, P=0.003], T, D and TDI scores were significantly lower in nECRS group than those in nECRS group[Fï¼1, 43ï¼ =6.719, P=0.013; Fï¼1, 43ï¼ =4.890, P=0.032; Fï¼1, 43ï¼ =4.469, P=0.040]; There was a positive correlation between preoperative eosinophil-to-lymphocyte ratioï¼ELRï¼ and SNOT-22 olfactory score and how much it changesï¼r=0.455, P=0.002; r=-0.414, P=0.005ï¼, a negative correlation between T, TDI score and how much they change respectivelyï¼r=-0.431, P=0.003; r=-0.385, P=0.009; r=-0.383, P=0.010; r=-0.316, P=0.035ï¼. The latency of P3 was significantly shorter after operation than that before operation in all CRSwNP patients[Fï¼1, 14ï¼ =24.840, P<0.001], however, the amplitude has no significant surgical effect. Conclusion:FESS could significantly improve the olfactory function of CRSwNP patients, while changes in plasticity may occur in the olfactory cortex. In addition, the preoperative peripheral blood eosinophil granulocyte level can predict the postoperative olfactory improvement.
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Pólipos Nasales , Trastornos del Olfato , Rinitis , Sinusitis , Humanos , Estudios Prospectivos , Pólipos Nasales/complicaciones , Pólipos Nasales/cirugía , Rinitis/complicaciones , Rinitis/cirugía , Sinusitis/complicaciones , Sinusitis/cirugía , Trastornos del Olfato/etiología , Enfermedad Crónica , Endoscopía/efectos adversosRESUMEN
Dot1l is a histone methyltransferase without a SET domain and is responsible for H3K79 methylation, which marks active transcription. In contradiction, Dot1l also participates in silencing gene expression. The target regions and mechanism of Dot1l in repressing transcription remain enigmatic. Here, we show that Dot1l represses endogenous retroviruses in embryonic stem cells (ESCs). Specifically, the absence of Dot1l led to the activation of MERVL, which is a marker of 2-cell-like cells. In addition, Dot1l deletion activated the 2-cell-like state and predisposed ESCs to differentiate into trophectoderm lineage. Transcriptome analysis revealed activation of 2-cell genes and meiotic genes by Dot1l deletion. Mechanistically, Dot1l interacted with and co-localized with Npm1 on MERVL, and depletion of Npm1 similarly augmented MERVL expression. The catalytic activity and AT-hook domain of Dot1l are important to suppress MERVL. Notably, Dot1l-Npm1 restricts MERVL by regulating protein level and deposition of histone H1. Furthermore, Dot1l is critical for Npm1 to efficiently interact with histone H1 and inhibit ubiquitination of H1 whereas Npm1 is essential for Dot1l to interact with MERVL. Altogether, we discover that Dot1l represses MERVL through chaperoning H1 by collaborating with Npm1. Importantly, our findings shed light on the non-canonical transcriptional repressive role of Dot1l in ESCs.
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Retrovirus Endógenos , Animales , Ratones , Células Madre Embrionarias/metabolismo , Retrovirus Endógenos/genética , Retrovirus Endógenos/metabolismo , Histona Metiltransferasas/genética , Histonas/genética , Histonas/metabolismo , Metilación , Metiltransferasas/genéticaRESUMEN
Numerous compounds present in the ocean are contributing to the development of the biomedical field. Agarose, a polysaccharide derived from marine red algae, plays a vital role in biomedical applications because of its reversible temperature-sensitive gelling behavior, excellent mechanical properties, and high biological activity. Natural agarose hydrogel has a single structural composition that prevents it from adapting to complex biological environments. Therefore, agarose can be developed into different forms through physical, biological, and chemical modifications, enabling it to perform optimally in different environments. Agarose biomaterials are being increasingly used for isolation, purification, drug delivery, and tissue engineering, but most are still far from clinical approval. This review classifies and discusses the preparation, modification, and biomedical applications of agarose, focusing on its applications in isolation and purification, wound dressings, drug delivery, tissue engineering, and 3D printing. In addition, it attempts to address the opportunities and challenges associated with the future development of agarose-based biomaterials in the biomedical field. It should help to rationalize the selection of the most suitable functionalized agarose hydrogels for specific applications in the biomedical industry.
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Materiales Biocompatibles , Hidrogeles , Sefarosa/química , Hidrogeles/química , Materiales Biocompatibles/química , Ingeniería de Tejidos , Sistemas de Liberación de MedicamentosRESUMEN
In this study, three kinds of anhydrides with different structures were introduced into agar molecules to study the effects of varying degrees of substitution (DS) and anhydride structures on the physicochemical properties and curcumin (CUR) loading capacity. Increasing the carbon chain length and saturation of the anhydride affects the hydrophobic interaction and hydrogen bonding of the esterified agar, thereby changing the stable structure of the agar. Although the gel performance declined, the hydrophilic carboxyl group and the loose porous structure provide more binding sites for the adsorption of water molecules, hence providing excellent water retention (1700 %). Next, CUR was used as a hydrophobic active ingredient to study agar microspheres' drug encapsulation and in vitro release ability. Results showed that the excellent swelling and hydrophobic structure of esterified agar could promote the encapsulation of CUR (70.3 %). The release process is controlled by pH, and the release of CUR under weak alkaline conditions is significant, which can be explained by the pore structure, swelling characteristics, and carboxyl binding of agar. Therefore, this study shows the application potential of hydrogel microspheres in loading hydrophobic active ingredients and sustained release and provides the possibility for the application of agar in drug delivery systems.
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Curcumina , Curcumina/química , Agar , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Interacciones Hidrofóbicas e HidrofílicasRESUMEN
Agar was modified with glutaric anhydride (GA) in this study to expand its application in food and medicine. Glutaric anhydride-modified agar (GAR) can maintain high gel strength (1247.4 g/cm2) and improved transparency (82.7 %). The esterified agar formed by GA further formed a cross-linking molecule structure by increasing the reaction temperature. Notably, excellent freeze-thaw stability (24.1 %) and swelling property (3116.6 %) of GAR indicated that the carboxyl-terminal of modified agar improves its affinity with water. Therefore, satisfactory water permeability and expansive stone enable agar films to achieve high water absorption. Furthermore, GAR films exhibit a specific absorption capacity of tetracycline hydrochloride in weak acid solution, thereby suggesting its potential application as a sustainable drug delivery carrier. Finally, the structure of the modified agar was analyzed to explain the mechanism of binding water. Cryo-scanning electron microscopy (SEM) depicted the porous structure of the agar gel responsible for swelling, drug loading, and release. Low-field NMR results showed that GA improves agar gel's binding and free water content. According to our research results, these GAR hydrogel membranes with excellent properties have the potential to be used as effective drug delivery materials.
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Materiales Biocompatibles , Portadores de Fármacos , Agar/química , Fenómenos Químicos , Portadores de Fármacos/química , Agua/químicaRESUMEN
Studies have shown that phosphatase and tensin homolog deleted on chromosome ten (PTEN) participates in the regulation of cochlear hair cell survival. Bisperoxovanadium protects against neurodegeneration by inhibiting PTEN expression. However, whether bisperoxovanadium can protect against noise-induced hearing loss and the underlying mechanism remains unclear. In this study, we established a mouse model of noise-induced hearing loss by exposure to 105 dB sound for 2 hours. We found that PTEN expression was increased in the organ of Corti, including outer hair cells, inner hair cells, and lateral wall tissues. Intraperitoneal administration of bisperoxovanadium decreased the auditory threshold and the loss of cochlear hair cells and inner hair cell ribbons. In addition, noise exposure decreased p-PI3K and p-Akt levels. Bisperoxovanadium preconditioning or PTEN knockdown upregulated the activity of PI3K-Akt. Bisperoxovanadium also prevented H2O2-induced hair cell death by reducing mitochondrial reactive oxygen species generation in cochlear explants. These findings suggest that bisperoxovanadium reduces noise-induced hearing injury and reduces cochlear hair cell loss.
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Neuregulin-1 (NRG1)/erythroblastic leukaemia viral oncogene homologues 2 (ErbB2) pathway had been implicated in promoting differentiation and suppressing apoptosis of neuronal stem cells (NSCs) isolated from cochlear nucleus. In the current study, we aimed at determining the effects of NRG1/ErbB2 on mitochondrial (mt) function of NSCs. As expected, NRG1 increased the expression of mitofusin (Mfn) 1 and Mfn2 and decreased the expression of mitochondrial fission protein 1 (Fis1) and dynamin-related protein 1 (Drp1). However, after ErbB2 knockout, Mfn1 and Mfn2 expression decreased while Fis1 and Drp1 increased. Moreover, the increased mtDNA copy number and intracellular ATP level, elevated ATPase activities as well as decreased lactate production induced by NRG1 were partially reversed by ErbB2 knockout. Additionally, NRG1 treatment increased the activities of catalase, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and upregulated the protein expression of catalase, manganese superoxide dismutase (MnSOD), peroxisome proliferator-activated receptor-γ coactlvator-1α (PGC-1α), nuclear respiratory factor 1 (NRF1) and transcription factor A, mitochondrial (TFAM), which were also reversed by ErbB2 knockout. Furthermore, PGC-1α overexpression partially reversed the above effects of ErbB2 knockout. In conclusion, these findings suggest that the promotion of mitochondrial function of NRG1/ErbB2 axis is at least in part mediated by PGC-1α in NSCs from cochlear nucleus.
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Núcleo Coclear , Células-Madre Neurales , Antioxidantes/farmacología , Catalasa/metabolismo , Neurregulina-1/metabolismo , Núcleo Coclear/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Mitocondrias/metabolismo , Células-Madre Neurales/metabolismoRESUMEN
Neural differentiation of embryonic stem cells (ESCs) requires precisely orchestrated gene regulation, a process governed in part by changes in 3D chromatin structure. How these changes regulate gene expression in this context remains unclear. In this study, we observed enrichment of the transcription factor KLF4 at some poised or closed enhancers at TSS-linked regions of genes associated with neural differentiation. Combination analysis of ChIP, HiChIP and RNA-seq data indicated that KLF4 loss in ESCs induced changes in 3D chromatin structure, including increased chromatin interaction loops between neural differentiation-associated genes and active enhancers, leading to upregulated expression of neural differentiation-associated genes and therefore early neural differentiation. This study suggests KLF4 inhibits early neural differentiation by regulation of 3D chromatin structure, which is a new mechanism of early neural differentiation.
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Cromatina , Células Madre Embrionarias , Factor 4 Similar a Kruppel , Diferenciación Celular/genética , Cromatina/metabolismo , Células Madre Embrionarias/metabolismo , Regulación de la Expresión Génica , Factores de Transcripción/metabolismo , Factor 4 Similar a Kruppel/metabolismoRESUMEN
κ-carrageenases are members of the glycoside hydrolase family 16 (GH16) that hydrolyze sulfated galactans in red algae, known as κ-carrageenans. In this study, a novel κ-carrageenase gene from the marine bacterium Rhodopirellula sallentina SM41 (RsCgk) was discovered via the genome mining approach. There are currently no reports on κ-carrageenase from the Rhodopirellula genus, and RsCgk shares a low identity (less than 65%) with κ- carrageenase from other genera. The RsCgk was heterologously overexpressed in Escherichia coli BL21 and characterized for its enzymatic properties. RsCgk exhibited maximum activity at pH 7.0 and 40 °C, and 50% of its initial activity was retained after incubating at 30 °C for 2 h. More than 70% of its activity was maintained after incubation at pH 6.0-8.0 and 4 °C for 24 h. As a marine derived enzyme, RsCgk showed excellent salt tolerance, retaining full activity in 1.2 M NaCl, and the addition of NaCl greatly enhanced its thermal stability. Mass spectrometry analysis of the RsCgk hydrolysis products revealed that the enzyme had high degradation specificity and mainly produced κ-carrageenan disaccharide. Comparative molecular dynamics simulations revealed that the conformational changes of tunnel-forming loops under salt environments may cause the deactivation or stabilization of RsCgk. Our results demonstrated that RsCgk could be utilized as a potential tool enzyme for efficient production of κ-carrageenan oligosaccharides under high salt conditions.
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Tolerancia a la Sal , Cloruro de Sodio , Carragenina/química , Bacterias/metabolismo , Glicósido Hidrolasas/metabolismo , Proteínas Bacterianas/metabolismoRESUMEN
A novel agar-based Pickering emulsion stabilizer was developed through the hydrophobic modification and microgelation of agar. After hexanoylation, the three-phase contact angle of hexanoylated agar (HAG) particles was adjusted from approximately 60° to 96° closing to neutral wettability. After microgelation, the particle size of the modified agar microgel was approximately 2 µm and Zeta potential reached -23.63 mV. Confocal laser microscopy and cryogenic scanning electron microscopy showed that HAG microgels formed a gel network or embedded on the surface of oil droplets, thus providing a dense barrier for oil droplets to coalesce and Ostwald ripening. The oil volume fraction and particle concentration had a significant effect on the droplet size and rheological properties of the Pickering emulsion. Pickering emulsion gels with long-term storage stability was prepared at low particle concentrations (0.7 wt%) and lower oil fractions (φ = 0.3- 0.5), which might become a new effective delivery system for bioactive substances.
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Microgeles , Agar , Emulsiones/química , Geles/química , Interacciones Hidrofóbicas e Hidrofílicas , Tamaño de la PartículaRESUMEN
In this study, a new method for preparing macroporous rigid agarose microspheres was developed by one-step pre-crosslinking method with cyclic anhydride. Three different cyclic anhydrides, namely, maleic anhydride, succinic anhydride, and glutaric anhydride, were used to pre-crosslink agarose. The reaction temperature and the amount of cyclic anhydride in the pre-crosslinking process were optimized to endow agarose with stronger cross-linking. Under the optimal cross-linking condition, macroporous rigid agarose microspheres with homogeneous particle size were successfully obtained by adjusting emulsification method. Cryo-scanning electron microscopy was used to characterize the morphology of cross-linked agarose gel and microspheres. The addition of cyclic anhydride increased the gel aperture of cross-linked agarose microspheres, thereby making the macropores in the microspheres more dense and enhancing the mass transfer in the particles. Under low pressure, the cross-linked agarose microsphere column can effectively separate model proteins at linear flow rates three times higher than the agarose microsphere column. These results indicate that the developed agarose microspheres are a promising high-speed chromatographic medium.
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Anhídridos , Anhídridos Maleicos , Microesferas , Sefarosa/química , Anhídridos/química , Tamaño de la PartículaRESUMEN
Long noncoding RNAs (lncRNAs) emerge as important orchestrators of biological processes in embryonic stem cells (ESCs). LncRNA Lx8-SINE B2 was recently identified as an ESC-specific lncRNA that marks pluripotency. Here, we studied the function of lncRNA Lx8-SINE B2 in ESCs. Depletion of Lx8-SINE B2 disrupted ESC proliferation, repressed the expression of pluripotency genes, activated differentiation genes, and inhibited reprogramming to induced pluripotent stem cells. The reduction of the colony formation ability of ESCs upon Lx8-SINE B2 knockdown was accompanied by the elongation of the G1 phase and the shortening of the S phase. Transcriptome analysis revealed that Lx8-SINE B2 deficiency affected multiple metabolic pathways, particularly glycolysis. Mechanistically, Lx8-SINE B2 functions as a cytoplasmic lncRNA and interacts with the glycolytic enzyme Eno1 as shown by RNA pull-down and RNA localization analysis. Lx8-SINE B2 and Eno1 interact with and regulate each other's expression, hence promoting the expression of metabolic genes and influencing glycolysis. In conclusion, we have identified lncRNA Lx8-SINE B2 as a novel regulator of ESC proliferation, cell cycle, and metabolism through working with Eno1.
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Células Madre Pluripotentes Inducidas , ARN Largo no Codificante , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Células Madre Embrionarias/metabolismo , Diferenciación Celular/genética , Perfilación de la Expresión Génica , Células Madre Pluripotentes Inducidas/metabolismoRESUMEN
Objective:According to the characteristics of endoscopic transnasal and transoral surgery for infratemporal fossa tumors, we divided and named subzones of the infratemporal fossa, to explore the approaches of endoscopic transnasal and transoral surgery for infratemporal fossa tumors, and to analyze their advantages and disadvantages. Methods:We retrospectively analyzed the clinical data of 36 patients with benign tumors of infratemporal fossa successfully resected through nose or mouth under endoscope, summarized and analyzed the localization characteristics of these tumors in infratemporal fossa, and made a subzone naming rule of infratemporal fossa. We also summarized the selection principles, advantages and disadvantages of endoscopic transnasal and transoral surgical approaches. Results:The infratemporal fossa area is divided into ABC area. Area A is the fat pad area posterolateral of maxillary sinus. Area B is further divided into B1 ï¼above the plane of maxillary sinus floor, anterior styloid processï¼, B2 ï¼below the plane of maxillary sinus floor, anterior styloid processï¼, and B3 ï¼posterior styloid process to anterior vertebraï¼; Area C is retropharyngeal and eustachian tube area. The location of the tumor in the infratemporal fossa determines the choice of transnasal and transoral approaches. All tumors were completely removed, and no tumor recurred during the follow-up. A few patients had temporary local sensory function decline, and recovered during the follow-up. Conclusion:The infratemporal fossa region naming rule according to the characteristics of endoscopic transoral and transnasal surgery approach is simple and practical, which can effectively guide the operation of the infratemporal fossa region and has clinical application value.
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Fosa Infratemporal , Procedimientos Quirúrgicos Orales , Elevación del Piso del Seno Maxilar , Endoscopía , Humanos , Seno Maxilar , Recurrencia Local de Neoplasia , Estudios RetrospectivosRESUMEN
An eco-friendly method for ι-carrageenan extraction from seaweed Eucheuma denticulatum through boiling and using a low concentration of Ca(OH)2 is reported. Compared to the traditional method of ι-carrageenan extraction using NaOH, the reported method using Ca(OH)2 had the advantages of using 93.3% less alkali and 86.8% less water, having a 25.0% shorter total extraction time, a 17.6% higher yield, and a 43.3% higher gel strength of the product. In addition, we evaluated the gel properties and structures of ι-carrageenan products extracted by Ca(OH)2 (Ca-IC) and NaOH (Na-IC). The Fourier transform infrared spectroscopy results showed that the structures of Ca-IC and Na-IC did not change remarkably. The results of the thermogravimetric analysis and differential scanning calorimetry showed that Ca-IC had the same thermal stability as Na-IC. The results of the textural analysis showed that Ca-IC had a higher hardness and better chewiness compared to Na-IC. Rheological results indicated that Ca-IC and Na-IC exhibited shear-thinning and non-Newtonian fluid properties, whereas the viscosity of Ca-IC was less than that of Na-IC. In conclusion, this new method of ι-carrageenan extraction using Ca-IC is markedly better and yields higher quality carrageenan than the conventional method of using Na-IC.