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1.
Anal Chem ; 96(15): 5931-5939, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38573171

RESUMO

Cuproptosis is a novel copper-dependent form of programmed cell death, displaying important regulatory functions in many human diseases, including cancer. However, the relationship between the changes in mitochondrial viscosity, a key factor associated with cellular malfunction, and cuproptosis is still unclear. Herein, we prepared a phosphorescent iridium (Ir) complex probe for precisely monitoring the changes of mitochondrial viscosity during cuprotosis via phosphorescence lifetime imaging. The Ir complex probe possessed microsecond lifetimes (up to 1 µs), which could be easily distinguished from cellular autofluorescence to improve the imaging contrast and sensitivity. Benefiting from the long phosphorescence lifetime, excellent viscosity selectivity, and mitochondrial targeting abilities, the Ir complex probe could monitor the increase in the mitochondrial viscosity during cuproptosis (from 46.8 to 68.9 cP) in a quantitative manner. Moreover, through in situ fluorescence imaging, the Ir complex probe successfully monitored the increase in viscosity in zebrafish treated with lipopolysaccharides or elescolomol-Cu2+, which were well-known cuproptosis inducers. We anticipate that this new Ir complex probe will be a useful tool for in-depth understanding of the biological effects of mitochondrial viscosity during cuproptosis.


Assuntos
Irídio , Peixe-Zebra , Animais , Humanos , Viscosidade , Peixe-Zebra/metabolismo , Linhagem Celular Tumoral , Células HeLa
2.
Water Sci Technol ; 89(7): 1787-1806, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619903

RESUMO

The conventional building drainage system was constructed based on the theory of two-phase flow involving water and air. However, the drainage system contained a more intricate three-phase flow, encompassing water, air, and solids, which was relatively overlooked in research. This study addressed the impact of solids on pressure fluctuations, air flow rates, and hydraulic jump fullness within the drainage system, considering three factors: the mass factor, cross-section factor, and viscosity. The investigation was conducted within a single-stack system using both experimental methods and CFD simulations. The findings revealed a positive correlation between both positive and negative pressures and above three factors. The mass factor and the cross-section factor had a more significant impact on the negative pressure of the system. The maximum growth rates of negative pressure extremes under different mass and cross-section factors reached 7.72 and 16.52%, respectively. In contrast, the viscosity of fecal sludge had a slightly higher effect on the positive pressure fluctuation of the drainage system, with the maximum growth rate of positive pressure extremes at 3.41%.


Assuntos
Esgotos , Água , Pressão do Ar , Pressão , Viscosidade
3.
Zhongguo Zhong Yao Za Zhi ; 49(3): 634-643, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621867

RESUMO

This paper aims to study the correlation between the physicochemical properties of raw materials and intermediates and the molding quality and law of traditional Chinese medicine(TCM) gel plaster by using TCM slices and powder as raw materials. 48 TCM compounds are selected as model prescriptions to prepare gel plasters. The rotational rheometer is used to determine the rheological parameters of the plaster, including storage modulus(G'), loss modulus(G″), yield stress(τ), and creep compliance [J(t)]. The molding quality of the prepared TCM gel plaster is evaluated by subjective and objective measures. Clustering and principal component analysis are conducted to evaluate the physical properties of the plaster. By measuring the rheological properties of the plaster, the molding quality of the TCM gel plaster can be predicted, with an accuracy of 83.72% after seven days of modeling and 88.37% after 30 days of modeling. When the parameters such as G' and G″ of the plaster are large, and the [J(t)] is small, the molding quality of the plaster is better. When the plaster coating point is no less than 3, it is difficult to be coated. In addition, when the proportion of metal ions in the prescription is higher, the 30-day forming quality of the plaster is mainly affected, and the viscosity of the plaster is poor. If the prescription contains many acidic chemical components, the 7-day forming quality of the plaster is mainly affected, with many residuals. The results suggest that the rheological properties of the plaster can be used to predict the molding quality of TCM slice and powder gel plaster. It can provide a reference for the development of TCM gel plaster prescriptions.


Assuntos
Medicina Tradicional Chinesa , Prescrições , Pós , Viscosidade , Reologia
4.
Anal Chim Acta ; 1302: 342506, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38580410

RESUMO

BACKGROUND: Mitophagy plays indispensable roles in maintaining intracellular homeostasis in most eukaryotic cells by selectively eliminating superfluous components or damaged organelles. Thus, the co-operation of mitochondrial probes and lysosomal probes was presented to directly monitor mitophagy in dual colors. Nowadays, most of the lysosomal probes are composed of groups sensitive to pH, such as morpholine, amine and other weak bases. However, the pH in lysosomes would fluctuate in the process of mitophagy, leading to the optical interference. Thus, it is crucial to develop a pH-insensitive probe to overcome this tough problem to achieve exquisite visualization of mitophagy. RESULTS: In this study, we rationally prepared a pH-independent lysosome probe to reduce the optical interference in mitophagy, and thus the process of mitophagy could be directly monitored in dual color through cooperation between IVDI and MTR, depending on Förster resonance energy transfer mechanism. IVDI shows remarkable fluorescence enhancement toward the increase of viscosity, and the fluorescence barely changes when pH varies. Due to the sensitivity to viscosity, the probe can visualize micro-viscosity alterations in lysosomes without washing procedures, and it showed better imaging properties than LTR. Thanks to the inertia of IVDI to pH, IVDI can exquisitely monitor mitophagy with MTR by FRET mechanism despite the changes of lysosomal pH in mitophagy, and the reduced fluorescence intensity ratio of green and red channels can indicate the occurrence of mitophagy. Based on the properties mentioned above, the real-time increase of micro-viscosity in lysosomes during mitophagy was exquisitely monitored through employing IVDI. SIGNIFICANCE AND NOVELTY: Compared with the lysosomal fluorescent probes sensitive to pH, the pH-inert probe could reduce the influence of pH variation during mitophagy to achieve exquisite visualization of mitophagy in real-time. Besides, the probe could monitor the increase of lysosomal micro-viscosity in mitophagy. So, the probe possesses tremendous potential in the visualization of dynamic changes related to lysosomes in various physiological processes.


Assuntos
Corantes Fluorescentes , Mitofagia , Humanos , Concentração de Íons de Hidrogênio , Viscosidade , Células HeLa , Corantes Fluorescentes/química , Lisossomos/química
5.
J Texture Stud ; 55(2): e12829, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38581147

RESUMO

Tribology is the science of measuring friction between surfaces. While it has been widely used to investigate texture sensations of food applications, it is seldom applied in pure edible oil systems. In this research, we measured friction, viscosity, and solid fat content (SFC) of nine vegetable oils at 30 and 60°C. Polarized static microscopy was used to assess crystal formation between 60 and 30°C. Descriptive sensory analysis and quantification of oral oil coatings were performed on the oils at 60°C. Expressing the friction factor of oil over the Hersey number (calculated using high sheer-viscosity values) showed no differences in friction between 30 and 60°C, except for shea stearin. Static microscopy revealed crystallization occurred at 30°C for shea stearin, whereas no or few crystals were present for other oils. At 30°C, friction at 1 × 10-2 m/s showed an inverse correlation with SFC (R = -0.95) and with high shear rate viscosity (R = -0.84), as well as an inverse correlation (R = -0.73) with "oily mouthcoating" perception. These results suggest that friction could be a predictor of fat-related perceptions of simple oil systems. Additionally, we hypothesize that the presence of crystals in oils could lower friction via a ball-bearing lubrication mechanism.


Assuntos
Alimentos , Óleos de Plantas , Lubrificação , Viscosidade , Percepção
6.
Ultrason Sonochem ; 105: 106868, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38581798

RESUMO

The use of extracts rich in bioactive compounds is becoming increasingly common in the food, cosmetics, and pharmaceutical industries for the production of functional products. Araticum is a potential fruit to be analyzed due to its content of phenolic compounds, carotenoids and vitamins, with antioxidant properties. Therefore, this study aimed to investigate the effect of ultrasound on total phenolic compounds, total carotenoids, ascorbic acid, color, turbidity and rheology in araticum juice. Response surface methodology based on a central composite design was applied. Araticum juice was subjected to sonication at amplitude levels ranging from 20 to 100 % of the total power (400 W) at a constant frequency of 20 kHz for different durations (2 to 10 min). Morphological analysis was conducted to observe microscopic particles, and viscosity and suitability to rheological models (Newtonian, Power Law, and Herschel-Bulkley) were assessed. The ultrasonic probe extraction method was compared to the control juice. According to the responses, using the desirability function, the optimal conditions for extraction were determined to be low power (low amplitude) applied in a short period of time or low power applied in a prolonged time. These conditions allowed an ultrasonic probe to act on releasing bioactive compounds without degrading them. All three rheological models were suitable, with the Power Law model being the most appropriate, exhibiting non-Newtonian pseudoplastic behavior.


Assuntos
Reologia , Annona/química , Sucos de Frutas e Vegetais/análise , Carotenoides/química , Viscosidade , Ondas Ultrassônicas , Sonicação , Fenóis/química , Ácido Ascórbico/química
7.
Soft Matter ; 20(16): 3483-3498, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38587658

RESUMO

A breast-cancer tumor develops within a stroma, a tissue where a complex extracellular matrix surrounds cells, mediating the cancer progression through biomechanical and -chemical cues. Current materials partially mimic the stromal matrix in 3D cell cultures but methods for measuring the mechanical properties of the matrix at cell-relevant-length scales and stromal-stiffness levels are lacking. Here, to address this gap, we developed a characterization approach that employs probe-based microrheometry and Bayesian modeling to quantify length-scale-dependent mechanics and mechanical heterogeneity as in the stromal matrix. We examined the interpenetrating network (IPN) composed of alginate scaffolds (for adjusting mechanics) and type-1 collagen (a stromal-matrix constituent). We analyzed viscoelasticity: absolute-shear moduli (stiffness/elasticity) and phase angles (viscous and elastic characteristics). We determined the relationship between microrheometry and rheometry information. Microrheometry reveals lower stiffness at cell-relevant scales, compared to macroscale rheometry, with dependency on the length scale (10 to 100 µm). These data show increasing IPN stiffness with crosslinking until saturation (≃15 mM of Ca2+). Furthermore, we report that IPN stiffness can be adjusted by modulating collagen concentration and interconnectivity (by polymerization temperature). The IPNs are heterogeneous structurally (in SEM) and mechanically. Interestingly, increased alginate crosslinking changes IPN heterogeneity in stiffness but not in phase angle, until the saturation. In contrast, such changes are undetectable in alginate scaffolds. Our nonlinear viscoelasticity analysis at tumor-cell-exerted strains shows that only the softer IPNs stiffen with strain, like the stromal-collagen constituent. In summary, our approach can quantify the stromal-matrix-related viscoelasticity and is likely applicable to other materials in 3D culture.


Assuntos
Alginatos , Matriz Extracelular , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Humanos , Alginatos/química , Técnicas de Cultura de Células em Três Dimensões , Viscosidade , Células Estromais/citologia , Células Estromais/metabolismo , Elasticidade , Tecidos Suporte/química , Colágeno Tipo I/química , Colágeno Tipo I/metabolismo , Fenômenos Biomecânicos , Reologia , Modelos Biológicos , Teorema de Bayes
8.
J Texture Stud ; 55(2): e12833, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38634383

RESUMO

Videofluoroscopic swallowing study (VFSS), alongside flexible endoscopic evaluation of swallowing, represents the gold standard for diagnosing swallowing disorders and to determine severity, pathophysiology, and effective interventions, including texture modification. The clinical swallowing examination and assessment supplements these instrumental methods and serves as the basis for the modules of swallowing diagnostics. The adaptation of food and drink consistencies in dysphagia management has become widespread. For valid results of a VFSS with respect to confirming swallowing safety and efficiency of different liquid and food consistencies and textures, the use of uniform recipes containing radio-opaque contrast media is important. Our goal was to identify recipes that would produce consistencies that conform to the liquid and food levels of 0-7, as defined by the International Dysphagia Diet Standardization Initiative (IDDSI), with barium- and iodine-based contrast media, xanthan gum-based thickeners, and other edible components, which also show sufficient contrast on VFSS. In this study, we determined the different recipes using IDDSI testing methods and explored their radiological characteristics using a Philips MultiDiagnost Eleva fluoroscopy system and two different fluid contrast agents: barium- (Micropaque®) and iodine-based (Telebrix®). All recipes showed sufficient contrast on fluoroscopy and could be visualized in the amounts used for swallowing examinations. They were practical and easy to implement in terms of production and availability of the components. The homogeneity of the recipes diminished with higher IDDSI levels, which represent transitional food, but appeared still sufficient for fluoroscopic examination. The opacity did not significantly differ between the barium- and iodine-based contrast media.


Assuntos
Transtornos de Deglutição , Iodo , Humanos , Transtornos de Deglutição/diagnóstico , Meios de Contraste , Bário , Viscosidade
9.
Int J Biol Macromol ; 265(Pt 2): 131159, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38565484

RESUMO

A goal of this study is to explore the difference in rheological properties of xanthan gum (XG)-based mixtures with gum arabic (GA) or GA-based emulsion (GAE). The stability of GAE was improved by thickening with XG. The intrinsic viscosity of all mixtures decreased as GA concentration increased, implying an XG conformational transition from the disordered to the ordered form. All mixtures except for an XG-GA mixture at 6.0 % GA attained a higher consistency index value than XG alone, indicating synergistic interactions between the components. At a high GA concentration (>3.0 %), the XG-GAE mixture showed higher relative apparent viscosity values than the XG-GA mixture. All mixtures except for an XG-GA mixture at 6.0 % GA showed higher elastic modulus and lower viscous modulus values than XG alone. Consequently, all mixtures showed lower tan δ values (0.26-0.30) than XG alone (0.31). Moreover, with a high GA concentration (>1.5 %), the XG-GAE mixtures achieved lower relative tan δ values than XG-GA mixture. These results indicate that XG formed a higher weak gel-like network with GAE than GA. Overall, the findings demonstrate that the interaction between XG and GA is influenced by conformational changes in the latter in both aqueous and emulsion systems.


Assuntos
Goma Arábica , Gomas Vegetais , Emulsões , Polissacarídeos Bacterianos , Viscosidade , Reologia/métodos
10.
Luminescence ; 39(4): e4749, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38658767

RESUMO

Lipid droplet, an intracellular lipid reservoir, is vital for energy metabolism and signal transmission in cells. The viscosity directly affects the metabolism of lipid droplets, and the abnormal viscosity is associated with the occurrence and development of various diseases. Therefore, it is indispensable to develop techniques that can detect viscosity changes in intracellular lipid droplets. Based on twisted intramolecular charge transfer (TICT) mechanism, a novel small-molecule lipid droplet-targeted viscosity fluorescence probe PPF-1 was designed. The probe was easy to synthesize, it had a large Stokes shift, stable optical properties, and low bio-toxicity. Compared to being in methanol solution, the fluorescence intensity of PPF-1 in glycerol solution was increased 26.7-fold, and PPF-1 showed excellent ability to target lipid droplets. Thus, the probe PPF-1 could provide an effective means of detecting viscosity changes of lipid droplets and was of great value for physiological diagnosis of related diseases, pathological analysis, and medical research.


Assuntos
Corantes Fluorescentes , Gotículas Lipídicas , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Viscosidade , Gotículas Lipídicas/química , Humanos , Estrutura Molecular , Imagem Óptica , Espectrometria de Fluorescência
11.
J Phys Chem B ; 128(16): 3910-3918, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38607690

RESUMO

Viscosity, at the subcellular level, plays a crucial role as a physicochemical factor affecting microenvironment homeostasis. Abnormal changes in mitochondrial viscosity often lead to various diseases in the organism. Based on the twisted intramolecular charge transfer mechanism, four hemicyanine dye fluorescent probes (HT-SA, HT-SA-S, HT-Bzh, and HT-NA) were designed and synthesized for viscosity response. The single bond between the nitrogen-containing heterocycle and the carbon-carbon double in the structure of the probe bond served as the viscosity response site. Finally, the probe HT-Bzh was screened as the optimal mitochondrial viscosity probe according to its responsiveness, targeting, and interference resistance. The fluorescence intensity of the probe HT-Bzh increased 22-fold when the viscosity was increased from 13.75 to 811.2 cP. In summary, all four viscosity probes we have developed can be used in different applications depending on the external environment, providing a valuable reference for the design of potential tools to address viscosity monitoring in biological systems.


Assuntos
Carbocianinas , Corantes Fluorescentes , Mitocôndrias , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Viscosidade , Carbocianinas/química , Mitocôndrias/metabolismo , Mitocôndrias/química , Humanos , Células HeLa , Estrutura Molecular , Imagem Óptica
12.
Sci Rep ; 14(1): 9182, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649422

RESUMO

In order to obtain high yield pomelo peel pectin with better physicochemical properties, four pectin extraction methods, including hot acid extraction (HAE), microwave-assisted extraction (MAE), ultrasound-assisted extraction, and enzymatic assisted extraction (EAE) were compared. MAE led to the highest pectin yield (20.43%), and the lowest pectin recovery was found for EAE (11.94%). The physicochemical properties of pomelo peel pectin obtained by different methods were also significantly different. Pectin samples obtained by MAE had the highest methoxyl content (8.35%), galacturonic acid content (71.36%), and showed a higher apparent viscosity, thermal and emulsion stability. The pectin extracted by EAE showed the highest total phenolic content (12.86%) and lowest particle size (843.69 nm), showing higher DPPH and ABTS scavenging activities than other extract methods. The pectin extracted by HAE had the highest particle size (966.12 nm) and degree of esterification (55.67%). However, Fourier-transform infrared spectroscopy showed that no significant difference occurred among the different methods in the chemical structure of the extracted pectin. This study provides a theoretical basis for the industrial production of pomelo peel pectin.


Assuntos
Citrus , Ácidos Hexurônicos , Pectinas , Pectinas/química , Pectinas/isolamento & purificação , Citrus/química , Viscosidade , Tamanho da Partícula , Micro-Ondas , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Fracionamento Químico/métodos , Fenômenos Químicos , Frutas/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Fenóis/análise , Fenóis/química , Fenóis/isolamento & purificação , Esterificação
13.
AAPS PharmSciTech ; 25(5): 90, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649513

RESUMO

To formulate and optimize Ozenoxacin nano-emulsion using Quality by Design (QbD) concept by means of Box-Behnken Design (BBD) and converting it to a gel to form Ozenoxacin nano-emulgel followed by physico-chemical, in-vitro, ex-vivo and in-vivo evaluation. This study demonstrates the application of QbD methodology for the development and optimization of an effective topical nanoemulgel formulation for the treatment of Impetigo focusing on the selection of appropriate excipients, optimization of formulation and process variables, and characterization of critical quality attributes. BBD was used to study the effect of "% of oil, % of Smix and homogenization speed" on critical quality attributes "globule size and % entrapment efficiency" for the optimisation of Ozenoxacin Nano-emulsion. Ozenoxacin loaded nano-emulgel was characterized for "description, identification, pH, specific gravity, amplitude sweep, viscosity, assay, organic impurities, antimicrobial effectiveness testing, in-vitro release testing, ex-vivo permeation testing, skin retention and in-vivo anti-bacterial activity". In-vitro release and ex-vivo permeation, skin retention and in-vivo anti-bacterial activity were found to be significantly (p < 0.01) higher for the nano-emulgel formulation compared to the innovator formulation (OZANEX™). Antimicrobial effectiveness testing was performed and found that even at 70% label claim of benzoic acid is effective to inhibit microbial growth in the drug product. The systematic application of QbD principles facilitated the successful development and optimization of a Ozenoxacin Nano-Emulsion. Optimised Ozenoxacin Nano-Emulgel can be considered as an effective alternative and found to be stable at least for 6 months at 40 °C / 75% RH and 30 °C / 75% RH.


Assuntos
Antibacterianos , Emulsões , Impetigo , Quinolonas , Animais , Impetigo/tratamento farmacológico , Camundongos , Quinolonas/administração & dosagem , Quinolonas/química , Quinolonas/farmacologia , Quinolonas/farmacocinética , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Antibacterianos/química , Emulsões/química , Nanopartículas/química , Géis/química , Química Farmacêutica/métodos , Modelos Animais de Doenças , Aminopiridinas/administração & dosagem , Aminopiridinas/farmacologia , Aminopiridinas/química , Aminopiridinas/farmacocinética , Excipientes/química , Pele/efeitos dos fármacos , Pele/metabolismo , Testes de Sensibilidade Microbiana/métodos , Absorção Cutânea/efeitos dos fármacos , Administração Tópica , Viscosidade , Composição de Medicamentos/métodos
14.
Int Ophthalmol ; 44(1): 171, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587686

RESUMO

PURPOSE: To assess the dynamic viscosity of the lacrimal sac wall in patients with various origins of lacrimal duct obstruction. METHODS: The study was performed in 35 cases: 21 cases with primary nasolacrimal duct obstruction (PANDO) and 14 cases with secondary nasolacrimal duct obstruction after radioiodine therapy (SALDO). The study of biomechanical properties of the lacrimal sac was carried out using a test bench. The principle of the study was to indent the sample at a given speed and record the data obtained from the sensor of the force transmitted to the sample. The area under the curve (AUC) and the peak viscosity were calculated. A qualitative characteristic of the obtained curve was given. RESULTS: Median AUC in patients with PANDO was 17 × 106 [6 × 106; 19 × 106] N/m2 × s, in patients with SALDO 21 × 106 [13 × 106; 25 × 106] N/m2 × s. Intergroup differences were statistically significant (p = 0,048). The median peak viscosity in PANDO patients was 29 × 106 [25 × 106; 35 × 106] N/m2, in patients with SALDO 32 × 106 [21 × 106; 41 × 106] N/m2. The qualitative characteristics of the obtained curves differed. CONCLUSION: Biomechanical properties of the lacrimal sac may vary depending on the cause of obliteration of the lacrimal ducts. The integrated dynamic viscosity is significantly higher in SALDO patients due to exposure to radioiodine compared to that in PANDO patients.


Assuntos
Aparelho Lacrimal , Obstrução dos Ductos Lacrimais , Ducto Nasolacrimal , Humanos , Obstrução dos Ductos Lacrimais/diagnóstico , Radioisótopos do Iodo , Viscosidade
15.
Food Res Int ; 185: 114289, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38658073

RESUMO

A food adhesive comprising tannic acid (TA) and soybean protein isolate (SPI) was developed to establish a cohesive bond between soy protein gel and simulated fat. The impact of varying TA concentrations and pH levels on the adhesive's rheology, thermal stability, chemical structure, and tensile strength were investigated. Rheological results revealed a gradual decrease in adhesive viscosity with increasing TA content. Differential scanning calorimetry (DSC) and thermal gravimetric (TG) results indicated that the stability of the adhesive improved with higher TA concentrations, reaching its peak at 0.50% TA addition. The incorporation of TA resulted in the cross-linking of amino group in unfolded SPI molecules, forming a mesh structure. However, under alkaline conditions (pH 9), adhesive viscosity and stability increased compared to the original pH. This shift was due to the disruption of the SPI colloidal charge structure, an increase in the stretching of functional groups, further unfolding of the structure, and an enhanced binding of SPI to TA. Under the initial pH conditions, SPI reacted with TA's active site to form covalent crosslinked networks and hydrogen bonds. In alkaline condition, beyond hydrogen and ionic bonding, the catechol structure was oxidized, forming an ortho-quinone that crosslinked SPI and created a denser structure. Tensile strength measurements and freeze-thaw experiments revealed that the adhesive exhibited maximum tensile strength and optimal adhesion with 0.75% TA at pH 9, providing the best overall performance. This study provides a new formulation and approach for developing plant-based meat analogues adhesives.


Assuntos
Polifenóis , Reologia , Proteínas de Soja , Taninos , Resistência à Tração , Taninos/química , Proteínas de Soja/química , Concentração de Íons de Hidrogênio , Viscosidade , Adesivos/química , 60450
16.
Anal Chim Acta ; 1299: 342422, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38499425

RESUMO

BACKGROUND: Ferroptosis, as a novel form of cell death, is becoming one of the hot topics in cancer treatment research. It differs from necrosis and autophagy in that it involves the accumulation of lipid peroxides and is triggered by iron dependency. Recent studies have suggested that this mechanism may alter the viscosity or structure of lipid droplets (LDs). The relationship between LDs viscosity and ferroptosis remains an active area of research with limited reports at present. Additionally, there is a lack of effective anticancer drugs targeting the ferroptosis pathway to promote ferroptosis in tumour cells. Therefore, the development of tools to detect viscosity changes during ferroptosis and targeted therapeutic strategies is of great significance. RESULTS: By coupling 1,3-indandione with naphthalimide, including decamethylamine as a LDs recognition group, we designed and synthesized an environmental fluorescent probe that induces intramolecular charge transfer (TICT) effects. Notably, the diffusion and transport of intracellular substances may be affected in highly viscous environments. Under such conditions, intracellular iron ions may accumulate, leading to peroxide production and cellular damage, which can trigger ferroptosis. Therefore, WD-1 achieved excellent in situ bioimaging of LDs targeting and its viscosity during ferroptosis in HeLa cells and zebrafish. Furthermore, it was observed that WD-1 effectively differentiated between malignant and normal cells during this process, highlighting its potential significance in distinguishing cellular states. In addition, we used the antitumour drug paclitaxel to study ferroptosis in cancer cells. These findings not only provide an excellent tool for the development of the ferroptosis response, but also are crucial for understanding the biological properties of LDs during the ferroptosis response. SIGNIFICANCE AND NOVELTY: Based on a powerful tool of fluorescent probe with in vivo bioimaging, we developed WD-1 to track the impact of paclitaxel on the process of ferroptosis in living cells. Therefore, we preliminarily believe that paclitaxel may affect the occurrence of ferroptosis and control apoptosis in cancer cells. These findings not only serve as an exceptional tool for advancing our understanding of the ferroptosis response, but furthermore play a vital role in comprehending the biological characteristics of LDs in relation to ferroptosis.


Assuntos
Ferroptose , Gotículas Lipídicas , Humanos , Animais , Corantes Fluorescentes , Células HeLa , Viscosidade , Peixe-Zebra , Ferro , Paclitaxel/farmacologia
17.
MAbs ; 16(1): 2303781, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38475982

RESUMO

Early identification of antibody candidates with drug-like properties is essential for simplifying the development of safe and effective antibody therapeutics. For subcutaneous administration, it is important to identify candidates with low self-association to enable their formulation at high concentration while maintaining low viscosity, opalescence, and aggregation. Here, we report an interpretable machine learning model for predicting antibody (IgG1) variants with low viscosity using only the sequences of their variable (Fv) regions. Our model was trained on antibody viscosity data (>100 mg/mL mAb concentration) obtained at a common formulation pH (pH 5.2), and it identifies three key Fv features of antibodies linked to viscosity, namely their isoelectric points, hydrophobic patch sizes, and numbers of negatively charged patches. Of the three features, most predicted antibodies at risk for high viscosity, including antibodies with diverse antibody germlines in our study (79 mAbs) as well as clinical-stage IgG1s (94 mAbs), are those with low Fv isoelectric points (Fv pIs < 6.3). Our model identifies viscous antibodies with relatively high accuracy not only in our training and test sets, but also for previously reported data. Importantly, we show that the interpretable nature of the model enables the design of mutations that significantly reduce antibody viscosity, which we confirmed experimentally. We expect that this approach can be readily integrated into the drug development process to reduce the need for experimental viscosity screening and improve the identification of antibody candidates with drug-like properties.


Assuntos
Anticorpos Monoclonais , Imunoglobulina G , Anticorpos Monoclonais/química , Viscosidade , Imunoglobulina G/química , Mutação , Ponto Isoelétrico
18.
Biosens Bioelectron ; 254: 116233, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38518563

RESUMO

Intracellular microenvironment (viscosity and polarity) and peroxynitrite ions (ONOO-) are involved in maintaining cell morphology, cell function, and signaling so that it is crucial to explore their level changes in vitro and vivo. In this work, we designed and synthesized a mitochondria-targeted fluorescence probe XBL for monitoring the dynamic changes of viscosity, polarity, and ONOO- based on TICT and ICT mechanism. The fluorescence spectra showed obvious changes for polarity at 500 nm as well as ONOO- and viscosity at 660 nm, respectively. The XBL can image simultaneously viscosity, polarity, and ONOO- in cells, and the results showed excess ONOO- leaded to the increase of viscosity in mitochondrial. The ferroptosis process was accompanied by increase of intracellular viscosity and ONOO- levels (or decrease of polarity), which allowed us to better understand the relevant physiological and pathological processes. The XBL can distinguish normal cells and cancerous cells by the fluorescence intensity changes in green and red channels, and image viscosity in inflamed mice. Thus, XBL can provided the chemical tool to understand the physiological and pathological mechanisms of disease by simultaneous detection of viscosity, polarity and ONOO-.


Assuntos
Técnicas Biossensoriais , Corantes Fluorescentes , Camundongos , Animais , Viscosidade , Células RAW 264.7 , Mitocôndrias , Ácido Peroxinitroso
19.
PLoS One ; 19(3): e0301138, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38547107

RESUMO

The rheological properties of asphalt can well reflect its road performance, but the rheological properties of warm mix high viscosity asphalt (HVA) are unclear. In order to study the effect of warm mixing agent on rheological properties of HVA, two kinds of warm mixing agent EC120 (EC) and Evotherm M1 (M1) were selected to prepare warm mix HVA. The rheological properties of warm mix HVA at high temperature (135~195°C), medium temperature (0~80°C) and low temperature (-6~18°C) were studied by Brinell rotary viscosity test, dynamic shear rheological test (including temperature scanning, frequency scanning, linear amplitude scanning) and bending beam rheological test. The test results show that both EC and M1 have good viscosity reduction effect on HVA at high temperature, and can effectively reduce the construction temperature. At medium temperature, M1 can effectively improve the fatigue resistance of HVA, and the fatigue life can be increased by about 30% when the dosage is 0.6%. EC can increase the rutting factor of HVA and improve its resistance to deformation, but it will reduce its fatigue performance. When the dosage is 4%, the fatigue life will be reduced by about 9%. At low temperature, M1 can reduce the creep stiffness S, increase the creep rate m, and improve the low temperature performance of HVA, while EC has the opposite effect, weakening the low temperature performance of HVA. The results are helpful to understand the rheological properties of warm mix HVA and promote its application.


Assuntos
Temperatura Baixa , Hidrocarbonetos , Temperatura , Viscosidade
20.
Food Chem ; 446: 138900, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38428074

RESUMO

The fat in coconut milk contributes to unique flavour, while increasing fat content affects stability of the coconut milk. In this study, coconut water and fat were separated, recombined, and homogenized to obtain coconut milk with different fat contents (0-20 %). Emulsifying properties, stability, and digestibility of coconut milk with different fat contents were comprehensively evaluated. The results showed that as the fat content increased from 0 to 20 %, the droplet size increased from 2.18 to 4.70 µm and the viscosity showed an increasing trend. During storage and freeze-thaw, coconut milk with 5 % and 10 % fat content showed excellent stability. In addition, coconut milk with 10 % fat content had superior fat digestibility, which was related to high affinity of pancrelipase. In short, this study revealed that fat content below 10 % can withstand environmental factors such as storage, lipid oxidation, and freeze-thaw, which can be accurately developed as coconut milk products.


Assuntos
Cocos , Leite , Animais , Viscosidade
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