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1.
iScience ; 27(5): 109710, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38689646

RESUMO

Circular RNA is a special category of non-coding RNA that has emerged as epigenetic regulator of adipose tissue development. However, the mechanism governing intramuscular adipogenesis of circRNA remains largely uncharted. In this study, circMEF2C(2, 3), looped by MEF2C exons 2 and 3, was identified from the pig MEF2C gene. Expression of circMEF2C(2, 3) is upregulated in early stage of intramuscular adipogenesis and muscular tissue of lean pigs (DLY pig). Subsequently, overexpression or knockdown of circMEF2C(2, 3) reflected that it participates in promoting proliferation and inhibiting adipogenic differentiation in porcine intramuscular preadipocytes and murine C3H10T1/2 cells. Mechanically, circMEF2C(2, 3) competitively combined with miR-383 and miR-671-3p to the 3'-UTR of MEF2C, which maintains MEF2C expression in regulating proliferation and adipogenesis. In summary, circMEF2C(2, 3) is a key regulator in the proliferation and adipogenic differentiation of intramuscular adipogenesis, suggesting its potential as a multi-target strategy for adipose development and associated diseases.

2.
BMC Pediatr ; 24(1): 353, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778302

RESUMO

BACKGROUND: For adolescents, abnormal dipping patterns in blood pressure (BP) are associated with early-onset organ damage and a higher risk of cardiovascular disorders in adulthood. Obesity is one of the most common reasons for abnormal BP dipping in young people. However, it is unknown whether the severity of obesity is associated with BP dipping status and whether this association is sex-dependent. METHODS: 499 participants between 12 and 17 years old with overweight or obesity underwent ambulatory blood pressure monitoring (ABPM) between April 2018 and January 2019 in Beijing and Baoding. Participants were grouped by body mass index (BMI) into overweight (BMI 85th-95th percentile), obese (BMI ≥ 95th percentile) and severely obese (BMI ≥ 120% of 95th percentile or ≥ 35 kg/m2) groups. Non-dipping was defined as a < 10% reduction in BP from day to night. The interaction effect between sex and obesity degree was also analyzed. RESULTS: 326 boys and 173 girls were included, of whom 130 were overweight, 189 were obese, and 180 were severely obese. Girls with severe obesity had a higher prevalence of non-dipping, but boys showed no significant differences in BP dipping status between obesity categories. In addition, as obesity severity went up, a more evident increase in night-time SBP was observed in girls than in boys. CONCLUSIONS: Severely obese is associated with a higher prevalence of non-BP dipping patterns in girls than in boys, which suggests that the relationship between the severity of obesity and BP dipping status might be sex-specific.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea , Ritmo Circadiano , Obesidade Infantil , Humanos , Feminino , Adolescente , Masculino , Pressão Sanguínea/fisiologia , Fatores Sexuais , Obesidade Infantil/complicações , Obesidade Infantil/fisiopatologia , Obesidade Infantil/epidemiologia , Criança , Ritmo Circadiano/fisiologia , Adiposidade , Sobrepeso/complicações , Sobrepeso/epidemiologia , Índice de Massa Corporal , China/epidemiologia , Índice de Gravidade de Doença , Estudos Transversais
3.
Artigo em Inglês | MEDLINE | ID: mdl-38598095

RESUMO

Ochratoxin A (OTA) is a toxic fungal metabolite that is commonly found in cereals and animal feed. It is economically damaging and potentially hazardous to human health. Herein, we propose an electrochemical immunosensor for the rapid detection of OTA using anti-OTA antibodies and diazonium-functionalized, screen-printed electrodes. We attached 4-aminobenzoic acid to an electrode surface, activated the carboxyl groups on the surface with carbodiimide, and attached an antibody to the diazo layer. Subsequently, we used bovine serum protein as a blocker to prevent non-specific antigens from binding to the antibody. We evaluated the performance of the sensor by cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry. The sensor is highly specific and sensitive, has good linear responses in the range 20-200 ng/mL, a limit of detection of 0.5 ng/mL, and good recoveries of 90.5%-100.9% in spiked samples. It can be stored at 4 °C for approximately 2 weeks, and is highly stable, with a current response variation of no more than 4.6%.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124084, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38442615

RESUMO

Peroxynitrite (ONOO-) is a highly reactive oxygen species that plays a critical role in many physiological and pathological processes of cell function. This study aimed to propose a ratiometric fluorescent probe BDHCA derived from coumarin for determining the ONOO- level. ONOO- could specifically induce oxidative cleavage of the conjugated C = C double bond in probe BDHCA, providing a fluorescent ratiometric output. The response of probe BDHCA to ONOO- was selective, fast, and highly sensitive, with a detection limit of 50.3 nM. Biological imaging experiments suggested that probe BDHCA could be used to image ONOO- in living RAW264.7 cells and zebrafish.


Assuntos
Corantes Fluorescentes , Peixe-Zebra , Camundongos , Animais , Corantes Fluorescentes/química , Ácido Peroxinitroso , Estresse Oxidativo , Células RAW 264.7
5.
Diabetol Metab Syndr ; 16(1): 62, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448958

RESUMO

OBJECTIVES: we performed this meta- analysis to investigate the impact of insulin receptor substrate 1 (IRS1) gene rs1801278 on susceptibility to gestational diabetes mellitus (GDM). METHODS: The pooled odds ratio (OR) and 95% confidence interval (95% CI) were calculated, and p value is used to determine statistical significance. Sensitivity analysis was performed under three models (dominant, recessive and allele model), and the pooled ORs and 95%CI were calculated. Funnel plots and Begger's regression test were employed to test the publication bias. RESULTS: The meta-analysis included 4777 participants (2116 cases and 2661 controls). The IRS1 rs1801278 (C/T) were not significant associated with GDM risk under the dominant and allele models, OR (95%CI) = 1.22 (0.88-1.70) and 1.24 (0.91-1.68), respectively (both p values were more than 0.05). But we also found the IRS1 rs1801278 (C/T) were significant associated with GDM risk under the recessive model, OR (95%CI) = 0.37 (0.16-0.86), p = 0.030. Our results showed that none of the studies affected the quality of the pooled OR. We also found no significant publication bias existed in this meta study for three genetic models, PTT + CT vs. CC = 0.445; PCC+CT vs. TT= 0.095; PC vs. T = 0.697. CONCLUSION: this meta-analysis indicated that IRS1 rs1801278 (C/T) was associated with the GDM risk under the recessive model but was not associated with the GDM risk under dominant and allele models.

6.
J Environ Manage ; 352: 120045, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38232591

RESUMO

The world is currently facing urgent climate and environmental issues, such as global warming, ecosystem collapse, and energy shortages. In this context, this study selected data from 2000 to 2021 and employed the Method of Moment Quantile Regression (MMQR) to thoroughly investigate the impact of renewable energy consumption, economic complexity, and geopolitical risks on the ecological footprint of the Group of Twenty (G20) countries. The results indicate that in countries with lower quantiles, renewable energy consumption significantly reduces the ecological footprint, whereas its effect is not prominent in countries with higher quantiles. Economic complexity has a negative impact on the ecological footprint, and this impact becomes stronger as the quantile of the ecological footprint rises. Additionally, economic complexity moderates the effect of renewable energy on the ecological footprint. Geopolitical risks facilitate the growth of the ecological footprint. Likewise, robustness tests such as DOLS, FMOLS, and quantile regression confirm these estimates in the same framework. This study has conducted a profound analysis of global environmental issues, offering innovative perspectives and recommendations for achieving goals related to sustainable energy utilization, mitigating climate change, and improving the ecological environment. The findings of this research will guide policymakers in G20 countries to adopt more effective environmental protection measures, thereby contributing to the construction of a sustainable future.


Assuntos
Ecossistema , Resiliência Psicológica , Desenvolvimento Econômico , Dióxido de Carbono , Energia Renovável
7.
Anal Methods ; 15(40): 5311-5315, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37791476

RESUMO

As a significant kind of reactive oxygen species (ROS), peroxynitrite (ONOO-) plays an indispensable role in many physiological and pathological processes. This study aimed to synthesize a novel dihydro-benzo[4,5]imidazo[1,2-c]quinazoline-based probe 1 for detecting ONOO-. In 99.5% H2O solution, probe 1 displayed a distinct aggregation-induced ratiometric emission (AIRE), and would selectively respond toward ONOO-via a ratiometric fluorescent signal, along with a short response time (<30 s) and ultra-sensitivity (LOD = 17.6 nM). Moreover, the probe was applied for monitoring the concentration fluctuations of ONOO- in HeLa cells and zebrafish.


Assuntos
Corantes Fluorescentes , Peixe-Zebra , Humanos , Animais , Ácido Peroxinitroso , Células HeLa , Espécies Reativas de Oxigênio
8.
Heliyon ; 9(9): e20296, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809651

RESUMO

We investigate the effect of the adoption of electric vehicles (EVs) on CO2 emissions using spatial econometric models and have three findings. First, there are spatial spillover effects of EV adoption on CO2 emissions, implying that the CO2 mitigation of a city depends on local sales of EVs and sales of EVs in neighboring cities. A 1% increase in the sale of EVs in a city can reduce CO2 emissions locally by 0.096% and by 0.087% in a nearby city. Second, EVs indirectly impact CO2 emissions through the substitution effect, energy consumption effect, and technological effect. The overall impact of EV adoption on CO2 emissions is negative. Finally, we demonstrate the moderating effect of urban energy structure on EVs' CO2 emissions mitigation. A 1% increase in the proportion of renewable energy generation increases the decarbonization of EVs by 0.036%. These findings provide policy implications for the coordinated development of EV market and energy system.

9.
J Colloid Interface Sci ; 650(Pt B): 1983-1992, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37527603

RESUMO

Developing a high-efficiency photoelectrochemical (PEC) electrode for the glycerol oxidation reaction (GOR) is important for producing valuable products. The PEC performance could be enhanced by rationally designing heterostructures with inhibited recombination of charge carriers. Nevertheless, the interface electronic structure of heterostructures has not been comprehensively analyzed. In this work, the PEC GOR performance of ZnIn2S4/TiO2 heterostructure photoanode showed 1.7 folds enhancement than that of pure TiO2 photoanode at 1.23 V vs. RHE. The ZnIn2S4/TiO2 heterostructure was simulated by constructing ZnIn2S4 on the TiO2 single crystal, which was beneficial for investigating the interface electronic structure of heterostructure. Single-particle spectroscopy demonstrated a significantly increased lifetime of charge carriers. Combined with the in-situ X-ray photoelectron spectroscopy, Kelvin probe force microscopy, work function, and electron paramagnetic resonance, the interface electronic structure of the ZnIn2S4/TiO2 heterostructure was proposed with a Z-scheme mechanism. This work provides a comprehensive strategy for analyzing the interface electronic structure of heterostructures.

10.
Dalton Trans ; 52(32): 11062-11066, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37519129

RESUMO

An inorganic-organic hybrid probe MP-ZIF-90 was synthesized via a simple condensation reaction based on the free CHO groups of zeolitic imidazolate framework-90 (ZIF-90) and 4-methyl-1-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)pyridinium bromide (MP). This probe exhibited intense green emission, which was selectively quenched by the addition of ClO- anions. The response of probe MP-ZIF-90 toward ClO- was rapid (within 20 s) and sensitive, with a limit of detection (LOD) of 0.612 µM. Importantly, the utilization of the probe in the fluorescence imaging of ClO- anions in the mitochondria of living cells and zebrafish was demonstrated.


Assuntos
Corantes Fluorescentes , Zeolitas , Animais , Peixe-Zebra , Ácido Hipocloroso , Mitocôndrias
11.
PLoS Comput Biol ; 19(6): e1011193, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37384793

RESUMO

Gestational Diabetes Mellitus (GDM), a serious complication during pregnancy which is defined by abnormal glucose regulation, is commonly treated by diabetic diet and lifestyle changes. While recent findings place the microbiome as a natural mediator between diet interventions and diverse disease states, its role in GDM is still unknown. Here, based on observation data from healthy pregnant control group and GDM patients, we developed a new network approach using patterns of co-abundance of microorganism to construct microbial networks that represent human-specific information about gut microbiota in different groups. By calculating network similarity in different groups, we analyze the gut microbiome from 27 GDM subjects collected before and after two weeks of diet therapy compared with 30 control subjects to identify the health condition of microbial community balance in GDM subjects. Although the microbial communities remain similar after the diet phase, we find that the structure of their inter-species co-abundance network is significantly altered, which is reflected in that the ecological balance of GDM patients was not "healthier" after the diet intervention. In addition, we devised a method for individualized network analysis of the microbiome, thereby a pattern is found that GDM individuals whose microbial networks are with large deviations from the GDM group are usually accompanied by their abnormal glucose regulation. This approach may help the development of individualized diagnosis strategies and microbiome-based therapies in the future.


Assuntos
Diabetes Gestacional , Microbioma Gastrointestinal , Microbiota , Gravidez , Feminino , Humanos , Microbioma Gastrointestinal/fisiologia , Dieta , Glucose
12.
Front Cell Dev Biol ; 11: 1112890, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37325554

RESUMO

Suture mesenchymal stem cells (SMSCs) are a heterogeneous stem cell population with the ability to self-renew and differentiate into multiple cell lineages. The cranial suture provides a niche for SMSCs to maintain suture patency, allowing for cranial bone repair and regeneration. In addition, the cranial suture functions as an intramembranous bone growth site during craniofacial bone development. Defects in suture development have been implicated in various congenital diseases, such as sutural agenesis and craniosynostosis. However, it remains largely unknown how intricate signaling pathways orchestrate suture and SMSC function in craniofacial bone development, homeostasis, repair and diseases. Studies in patients with syndromic craniosynostosis identified fibroblast growth factor (FGF) signaling as an important signaling pathway that regulates cranial vault development. A series of in vitro and in vivo studies have since revealed the critical roles of FGF signaling in SMSCs, cranial suture and cranial skeleton development, and the pathogenesis of related diseases. Here, we summarize the characteristics of cranial sutures and SMSCs, and the important functions of the FGF signaling pathway in SMSC and cranial suture development as well as diseases caused by suture dysfunction. We also discuss emerging current and future studies of signaling regulation in SMSCs.

13.
Anal Methods ; 15(22): 2761-2765, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37255236

RESUMO

The high toxicity of phosgene poses potential threats to public health and safety. In this work, a novel fluorescent probe was designed to detect phosgene using hydroxyl and pyrazole moieties as the recognition sites. The response to phosgene with probe 1 was fast (less than 30 s), highly selective and sensitive with the limit of detection being 4.78 nM in solution. Furthermore, probe 1 was employed to conveniently fabricate paper test strips for efficiently detecting phosgene gas. The limit of detection was obtained as 0.014 ppm by using a smartphone RGB app, revealing that probe 1 has good prospects for sensitively detecting phosgene gas.


Assuntos
Fosgênio , Espectrometria de Fluorescência , Cumarínicos , Corantes Fluorescentes
14.
Front Public Health ; 11: 1170334, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37181695

RESUMO

Objective: The purpose of our study was to investigate the association of obesity status change with hypertension onset based on a community-based longitudinal cohort study in North China. Methods: This longitudinal study included 3,581 individuals free of hypertension at baseline in the first survey (2011-2012). All participants were followed up (2018-2019). According to the criteria, a total of 2,618 individuals were collected for analysis. We used adjusted Cox regression models and Kaplan-Meier survival analysis to estimate the association between obesity status change and hypertension onset. Additionally, we applied the forest plot to visualize the subgroup analysis including age, gender, and the differences in some variables between baseline and follow-up. Finally, we conducted a sensitivity analysis to examine the stability of our results. Results: Over nearly 7 years of follow-up, a total of 811 (31%) developed hypertension. The new hypertension incidence was mostly observed in those who were obese all the time (P for trend < 0.01). In the fully adjusted Cox regression model, being obese all the time increased the risk of hypertension by 30.10% [HR 4.01 (95% CI 2.20-7.32)]. The Kaplan-Meier survival analysis revealed the change in obesity status as an important feature to predict the occurrence of hypertension. Sensitivity analysis shows a consistent trend between the change in obesity status and hypertension onset in all populations. Subgroup analysis showed that age above 60 years was an important risk factor for hypertension onset, that men were more likely than women to develop hypertension, and that weight control was beneficial in avoiding future hypertension in women. There were statistically significant differences in ΔBMI, ΔSBP, ΔDBP, and ΔbaPWV between the four groups, and all variables, except baPWV changes, increased the risk of future hypertension. Conclusion: Our study shows that obese status was notably associated with a significant risk of hypertension onset among the Chinese community-based cohort.


Assuntos
Hipertensão , Obesidade , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Longitudinais , Obesidade/epidemiologia , Obesidade/complicações , Fatores de Risco , Estudos de Coortes , Hipertensão/epidemiologia
15.
Front Neurosci ; 17: 1125677, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37008205

RESUMO

Purpose: Investigating the changes of regional homogeneity (ReHo) values and both static and dynamic functional connectivity (FC) before and after Traditional Chinese Manual Therapy (Tuina) in patients with lumbar disk herniation (LDH) through resting-state functional magnetic resonance imaging (RS-fMRI). Based on this, we observe the effect of Tuina on the above abnormal changes. Methods: Patients with LDH (n = 27) and healthy controls (HCs) (n = 28) were recruited. The functional magnetic resonance imaging (fMRI) scanning was performed two times in LDH patients, before Tuina (time point 1, LDH-pre) and after the sixth Tuina (time point 2, LDH-pos). And for one time in HCs which received no intervention. The ReHo values were compared between LDH-pre and HCs. The significant clusters detected by ReHo analysis were selected as seeds to calculate static functional connectivity (sFC). We also applied the sliding-window to perform dynamic functional connectivity (dFC). To evaluate the Tuina effect, the mean ReHo and FC values (both static and dynamic) were extracted from significant clusters and compared between LDH and HCs. Results: In comparison to HCs, LDH patients displayed decreased ReHo in the left orbital part middle frontal gyrus (LO-MFG). For sFC analysis, no significant difference was found. However, we found decreased dFC variance between LO-MFG and the left Fusiform, and increased dFC variance in the left orbital inferior frontal gyrus and left precuneus. Both ReHo and dFC values revealed after Tuina, the brain activities in LDH patients were similar to HCs. Conclusion: The present study characterized the altered patterns of regional homogeneity in spontaneous brain activity and those of functional connectivity in patients with LDH. Tuina can reshape the function of the default mode network (DMN) in LDH patients, which may contribute to the analgesic effect of Tuina in LDH patients.

16.
Spectrochim Acta A Mol Biomol Spectrosc ; 296: 122669, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37030252

RESUMO

Hypochlorite (ClO-) is a ROS that plays a crucial role in the immune system in the body. As the largest organelle in the cell, the endoplasmic reticulum (ER) manages various life activities. Thus, a simple hydrazone-based probe was designed, which provided a fast turn-on fluorescent response toward ClO-. With a terminal p-toluenesulfonamide group as the endoplasmic reticulum (ER)-specific site, probe 1 was mainly accumulated at ER of living cells, and could be used for imaging endogenous and exogenous HClO in cells and zebrafishes.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso , Animais , Peixe-Zebra , Benzopiranos , Imagem Óptica , Retículo Endoplasmático
17.
Opt Lett ; 48(5): 1132-1135, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36857231

RESUMO

We demonstrate a unidirectional ring diode laser based on hybrid integration of a hook-shaped traveling-wave semiconductor optical amplifier (SOA) and a Taiji ring resonator. The additional crossover bending waveguide inside the silicon nitride Taiji ring introduces a non-reciprocal loss in the laser cavity while the gain is provided by a multiple depth etched hook-shaped SOA. We present the detailed design flow for both active and passive components of the unidirectional hybrid diode laser. This work paves the way to use a hook-shaped SOA-based hybrid platform for various applications including optical sensing, all-optical switching, photonic memories, and topological optics.

18.
Membranes (Basel) ; 13(3)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36984644

RESUMO

In this study, the composite nanofiber membranes (AgNPs-PS/PET) composed of hydrophobic polystyrene (PS) embedded with different additions of silver nanoparticles (AgNPs) and hydrophilic hydrolyzed polyethylene terephthalate (PET) were prepared via electrospinning technology to achieve the function of unidirectional water penetration. The addition of AgNO3 was at 0 wt%, 0.5 wt%, 1.0 wt% and 1.5 wt% as the variables. The surface morphology and structure of AgNPs-PS/PET composite nanofibers were characterized by scanning electron microscopy (SEM), x-ray energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). The SEM image showed that the fibers of the composite materials were continuous and uniform as a result of electrospinning. The presence and content of Ag nanoparticles dispersed in the nanofibers were investigated using EDS and TEM. The contact angle (CA) was tested to illustrate the wettability of the composite nanofiber membranes using a static contact angle measuring instrument and the process of unidirectional water penetration was recorded. Meanwhile, the mechanism of unidirectional water penetration was analyzed. Moreover, the electrospinning solution's viscosity and conductivity were also investigated. Eventually, the optimal addition of AgNO3 (1.0 wt%) was confirmed and the prepared AgNPs-PS/PET composite nanofiber membranes were able to achieve the function of unidirectional water penetration. These membranes have the potential to be applied in smart textiles, unidirectional water collection and wound dressing.

19.
Anal Chim Acta ; 1245: 340867, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36737135

RESUMO

The microenvironments of biological systems are associated with the pathology of organisms. This study, aimed to construct a hemicyanine-based probe (1), which can respond to mitochondrial viscosity and hydrazine (N2H4), for imaging application in living cells and zebrafish. The probe showed no fluorescence due to the intramolecular rotation in the solution; however, it exhibited a strong emission at 730 nm when the molecules were restricted to a high-viscosity environment. The addition of N2H4 caused an elimination reaction of the N-substituted group in the pyridinium part and further broke the CC bond to produce a highly fluorescent hydrazone. Also, the probe could selectively and quantitatively detect N2H4 via the fluorescence enhancement at 510 nm in a concentration range of 0 µM-140µM, with the limit of detection being 0.0485 µM. This probe may be used to study diseases related to N2H4 and viscosity changes in biological systems. Furthermore, the analysis methods based on probe 1 for N2H4 detection in soil, water, and air samples were successfully established.


Assuntos
Corantes Fluorescentes , Peixe-Zebra , Humanos , Animais , Corantes Fluorescentes/química , Viscosidade , Água/química , Hidrazinas/análise , Células HeLa , Espectrometria de Fluorescência/métodos
20.
Polymers (Basel) ; 15(3)2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36771863

RESUMO

Utilizing the copolymerization modification of dimethyl diallyl ammonium chloride (DMDAAC), the high positive charge density of the copolymer could be maintained, thereby facilitating the deficiency of its monomer in the application. In this paper, poly (DMDAAC-co-DAMBAC) (9:1) was synthesized with an aqueous polymerization method using DMDAAC and methyl benzyl diallyl ammonium chloride (DAMBAC) as monomers and 2,2'-azobis [2-methylpropionamidine] dihydrochloride (V50) as an initiator. Targeted to the product's weight-average relative molecular mass (Mw), the response surface methodology (RSM) was used to optimize the preparation process. The optimal process conditions were obtained as follows: w (M) = 80.0%, m (V50):m (M) = 0.00700%, m (Na4EDTA):m (M) = 0.00350%, T1 = 50.0 °C, T2 = 60.0 °C, and T3 = 72.5 °C. The intrinsic viscosity ([η]) of the product was 1.780 dL/g, and the corresponding double bond conversion (Conv.) was 90.25 %. Poly (DMDAAC-co-DAMBAC) (9:1) revealed a highest Mw of 5.637 × 105, together with the polydispersity index d (Mw/Mn) as 1.464. For the demulsification performance of simulated crude oil O/W emulsions, the demulsification rate of poly (DMDAAC-co-DAMBAC) (9:1) could reach 97.73%. Our study has illustrated that the copolymerization of DMDAAC and a small amount of DAMBAC with poor reactivity could significantly improve the relative molecular weight of the polymer, enhance its lipophilicity, and thus the application scope of the polymer.

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