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1.
ACS Appl Mater Interfaces ; 16(23): 30496-30505, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38830306

ABSTRACT

Ionic current rectification (ICR) of charged conical nanopores has various applications in fields including nanofluidics, biosensing, and energy conversion, whose function is closely related to the dynamic response of nanopores. The occurrence of ICR originates from the ion enrichment and depletion in conical pores, whose formation is found to be affected by the scanning rate of voltages. Here, through time-dependent simulations, we investigate the variation of ion current under electric fields and the dynamic formation of ion enrichment and depletion, which can reflect the response time of conical nanopores. The response time of nanopores when ion enrichment forms, i.e., at the "on" state is significantly longer than that with the formation of ion depletion, i.e., at the "off" state. Our simulation results reveal the regulation of response time by different nanopore parameters including the surface charge density, pore length, tip, and base radius, as well as the applied conditions such as the voltage and bulk concentration. The response time of nanopores is closely related to the surface charge density, pore length, voltage, and bulk concentration. Our uncovered dynamic response mechanism of the ionic current can guide the design of nanofluidic devices with conical nanopores, including memristors, ionic switches, and rectifiers.

2.
Carbohydr Polym ; 339: 122296, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38823896

ABSTRACT

The diverse properties reported for starch-based materials indicate their potential for use in the preparation of biodegradable flexible actuators. However, their natural brittleness and lack of durability after modification limit their practical application. Therefore, we propose a strategy for preparing flexible starch-based composites. The results of macro/micro property characterizations and molecular dynamics simulations indicated that using starch, maleic anhydride, and stearic acid (SA), the mobility of the starch chains was enhanced and retrogradation was inhibited through the synergistic effects induced by chain breaking, complex formation with SA, and esterification of the starch molecules. In addition, the elongation at break of the modified starch (MS) reached 2070 %, and considerable ductility (>1000 %) as well as well-complexed structure were maintained after six months. Furthermore, the MS was able to undergo self-healing after fracture or a temperature-controlled stiffness transition. Moreover, it underwent complete degradation in soil within 30 d. Finally, an actuator was prepared by doping the MS with nano-Fe3O4 particles to realize a dual magnetic and optical response. Dynamic monitoring was also achieved based on the electrical signal, thereby demonstrating the broad application scope of this material in the development of biodegradable flexible actuators.

3.
Int J Biol Macromol ; 267(Pt 2): 131563, 2024 May.
Article in English | MEDLINE | ID: mdl-38626837

ABSTRACT

Excessive exudation from the wound site and the difficulty of determining the state of wound healing can make medical management more difficult and, in extreme cases, lead to wound deterioration. In this study, we fabricated a pH-sensitive colorimetric chronic wound dressing with self-pumping function using electrostatic spinning technology. It consisted of three layers: a polylactic acid-curcumin (PCPLLA) hydrophobic layer, a hydrolyzed polyacrylonitrile (HPAN) transfer layer, and a polyacrylonitrile-purple kale anthocyanin (PAN-PCA) hydrophilic layer. The results showed that the preparation of porous PLLA fiber membrane loaded with 0.2 % Cur was achieved by adjusting the spinning-related parameters, which could ensure that the composite dressing had sufficient anti-inflammatory, antibacterial and antioxidant properties. The HPAN membrane treated with alkali for 30 min had significantly enhanced liquid wetting ability, and the unidirectional transport of liquid could be achieved by simple combination with the 20 um PCPLLA fiber membrane. In addition, the 4 % loaded PCA showed more obvious color difference than the colorimetric membrane. In vivo and ex vivo experiments have demonstrated the potential of multifunctional dressings for the treatment of chronic wounds.


Subject(s)
Bandages , Curcumin , Polyesters , Wound Healing , Hydrogen-Ion Concentration , Polyesters/chemistry , Porosity , Animals , Wound Healing/drug effects , Curcumin/chemistry , Curcumin/pharmacology , Acrylic Resins/chemistry , Anthocyanins/chemistry , Anthocyanins/pharmacology , Hydrophobic and Hydrophilic Interactions , Rats , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Male , Antioxidants/pharmacology , Antioxidants/chemistry , Brassica/chemistry
4.
Int J Biol Macromol ; 267(Pt 1): 131406, 2024 May.
Article in English | MEDLINE | ID: mdl-38582472

ABSTRACT

Starch and plant fibers are abundant natural polymers that offer biodegradability, making them potential substitutes for plastics in certain applications, but are usually limited by its high hydrophilicity, and low mechanical performance. To address this issue, polylactic acid (PLA) is blended with cellulose and chitosan to create a waterproof film that can be applied to starch-fiber foaming biodegradable composites to enhance their water resistance properties. Here, plant fibers as a reinforcement is incorporated to the modified starch by foaming mold at 260 °C, and PLA based hydrophobic film is coated onto the surface to prepare the novel hydrophobic bio-composites. The developed bio-composite exhibits comprehensive water barrier properties, which is significantly better than that of traditional starch and cellulose based materials. Introducing PLA films decreases water vapor permeability from 766.83 g/m2·24h to 664.89 g/m2·24h, and reduce hysteresis angles from 15.57° to 8.59° within the first five minutes after exposure to moisture. The water absorption rate of PLA films also decreases significantly from 12.3 % to 7.9 %. Additionally, incorporating hydrophobic films not only enhances overall waterproof performance but also improves mechanical properties of the bio-composites. The fabricated bio-composite demonstrates improved tensile strength from 2.09 MPa to 3.53 MPa.


Subject(s)
Hydrophobic and Hydrophilic Interactions , Polyesters , Starch , Tensile Strength , Water , Polyesters/chemistry , Starch/chemistry , Water/chemistry , Permeability , Chitosan/chemistry , Cellulose/chemistry , Steam , Surface Properties
5.
ACS Appl Mater Interfaces ; 16(14): 17145-17162, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38534071

ABSTRACT

The fabrication of antifouling zwitterionic polymer brushes represents a leading approach to mitigate nonspecific adhesion on the surfaces of medical devices. This investigation seeks to elucidate the correlation between the material composition and structural attributes of these polymer brushes in preventing protein adhesion. To achieve this goal, we modeled three different zwitterionic brushes, namely, carboxybetaine methacrylate (CBMA), sulfobetaine methacrylate (SBMA), and (2-(methacryloyloxy)ethyl)-phosphorylcholine (MPC). The simulations revealed that elevating the grafting density enhances the structural stability, hydration strength, and resistance to protein adhesion exhibited by the polymer brushes. PCBMA manifests a more robust hydration layer, while PMPC demonstrates the slightest interaction with proteins. In a comprehensive evaluation, PSBMA polymer brushes emerged as the best choice with superior stability, enhanced protein repulsion, and minimally induced protein deformation, resulting in effective resistance to nonspecific adhesion. The high-density SBMA polymer brushes significantly reduce the level of protein adhesion in AFM testing. In addition, we have pioneered the quantitative characterization of hydration repulsion in polymer brushes by analyzing the hydration repulsion characteristics at different materials and graft densities. In summary, our study provides a nuanced understanding of the material and structural determinants influencing the capacity of zwitterionic polymer brushes to thwart protein adhesion. Additionally, it presents a quantitative elucidation of hydration repulsion, contributing to the advancement and application of antifouling polymer brushes.


Subject(s)
Polymers , Proteins , Polymers/chemistry , Physical Phenomena , Adsorption , Methacrylates/chemistry
6.
J Chem Phys ; 160(7)2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38363999

ABSTRACT

Short nanopores find extensive applications, capitalizing on their high throughput and detection resolution. Ionic behaviors through long nanopores are mainly determined by charged inner-pore walls. When pore lengths decrease to sub-200 nm, charged exterior surfaces provide considerable modulation to ion current. We find that the charge status of inner-pore walls affects the modulation of ion current from charged exterior surfaces. For 50-nm-long nanopores with neutral inner-pore walls, the charged exterior surfaces on the voltage (surfaceV) and ground (surfaceG) sides enhance and inhibit the ion transport by forming ion enrichment and depletion zones inside nanopores, respectively. For nanopores with both charged inner-pore and exterior surfaces, continuous electric double layers enhance the ion transport through nanopores significantly. The charged surfaceV results in higher ion current by simultaneously weakening the ion depletion at pore entrances and enhancing the intra-pore ion enrichment. The charged surfaceG expedites the exit of ions from nanopores, resulting in a decrease in ion enrichment at pore exits. Through adjustment in the width of charged-ring regions near pore boundaries, the effective charged width of the charged exterior is explored at ∼20 nm. Our results may provide a theoretical guide for further optimizing the performance of nanopore-based applications, such as seawater desalination, biosensing, and osmotic energy conversion.

7.
Acta Biomater ; 178: 111-123, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38423351

ABSTRACT

High-performance catheters are essential for interventional surgeries, requiring reliable anti-adhesive and lubricated surfaces. This article develops a strategy for constructing high-density sulfobetaine zwitterionic polymer brushes on the surface of catheters, utilizing dopamine and sodium alginate as the primary intermediate layers, where dopamine provides mussel-protein-like adhesion to anchor the polymer brushes to the catheter surface. Hydroxyl-rich sodium alginate increases the number of grafting sites and improves the grafting mass by more than 4 times. The developed high-density zwitterionic polymer brushes achieve long-lasting and effective lubricity (µ<0.0078) and are implanted in rabbits for four hours without bio-adhesion and thrombosis in the absence of anticoagulants such as heparin. Experiments and molecular dynamics simulations demonstrate that graft mass plays a decisive role in the lubricity and anti-adhesion of polymer brushes, and it is proposed to predict the anti-adhesion of polymer brushes by their lubricity to avoid costly and time-consuming bioassays during the development of amphoteric polymer brushes. A quantitative influence of hydration in the anti-adhesion properties of amphiphilic polymer brushes is also revealed. Thus, this study provides a new approach to safe, long-lasting lubrication and anticoagulant surface modification for medical devices in contact with blood. STATEMENT OF SIGNIFICANCE: High friction and bioadhesion on medical device surfaces can pose a significant risk to patients. In response, we have developed a safer, simpler, and more application-specific surface modification strategy that addresses both the lubrication and anti-bioadhesion needs of medical device surfaces. We used dopamine and sodium alginate as intermediate layers to drastically increase the grafting density of the zwitterionic brushes and enabled the modified surfaces to have an extremely low coefficient of friction (µ = 0.0078) and to remain non-bioadhesive for 4 hours in vivo. Furthermore, we used molecular dynamics simulations to gain insight into the mechanisms behind the superior anti-adhesion properties of the high-density polymer brushes. Our work contributes to the development and application of surface-modified coatings.


Subject(s)
Fibrinolytic Agents , Polymers , Animals , Humans , Rabbits , Polymers/pharmacology , Dopamine , Lubrication , Surface Properties , Alginates/pharmacology
8.
Int J Biol Macromol ; 254(Pt 3): 127653, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37918597

ABSTRACT

Thrombosis of extracorporeal circuits causes significant morbidity and mortality worldwide. In this study, plasma treatment technology and chemical grafting method were used to construct heparinized surfaces on the PVC substrate, which could not only reduce thrombosis but also decrease the side effects of the direct injection of anticoagulants. The PVC substrate was modified by plasma treatment technology firstly to obtain the active surface with the hydroxyl groups used for grafting. Then, heparin was grafted onto the modified PVC surface using different grafting strategies to prepare different heparinized surfaces. The experimental results indicated that the sodium alginate (SA) and carboxymethyl chitosan (CCS) used as interlayers could significantly increase the graft density of heparin to improve the anticoagulant effects and hemocompatibility of heparinized surfaces. In addition, the modification of heparin can further improve the anticoagulant effects. The CCS/low-molecular-weight heparin (LWMH) surface has the best anticoagulant properties, which can prolong the activated partial thromboplastin time (APTT) values of human plasma for about 35 s, reduce the hemolysis rates to <0.3 %, and perform well in the in-vitro blood circulation test. The heparinized surfaces prepared in this work have great application potential in anticoagulant treatment for medical devices.


Subject(s)
Chitosan , Thrombosis , Humans , Heparin/pharmacology , Heparin/chemistry , Polyvinyl Chloride , Chitosan/chemistry , Alginates , Anticoagulants/pharmacology , Anticoagulants/chemistry , Partial Thromboplastin Time
9.
Acta Biomater ; 175: 76-105, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38128641

ABSTRACT

The lubrication modification of biomedical devices significantly enhances the functionality of implanted interventional medical devices, thereby providing additional benefits for patients. Polymer brush coating provides a convenient and efficient method for surface modification while ensuring the preservation of the substrate's original properties. The current research has focused on a "trial and error" method to finding polymer brushes with superior lubricity qualities, which is time-consuming and expensive, as obtaining effective and long-lasting lubricity properties for polymer brushes is difficult. This review summarizes recent research advances in the biomedical field in the design, material selection, preparation, and characterization of lubricating and antifouling polymer brushes, which follow the polymer brush development process. This review begins by examining various approaches to polymer brush design, including molecular dynamics simulation and machine learning, from the fundamentals of polymer brush lubrication. Recent advancements in polymer brush design are then synthesized and potential avenues for future research are explored. Emphasis is placed on the burgeoning field of zwitterionic polymer brushes, and highlighting the broad prospects of supramolecular polymer brushes based on host-guest interactions in the field of self-repairing polymer brush applications. The review culminates by providing a summary of methodologies for characterizing the structural and functional attributes of polymer brushes. It is believed that a development approach for polymer brushes based on "design-material selection-preparation-characterization" can be created, easing the challenge of creating polymer brushes with high-performance lubricating qualities and enabling the on-demand creation of coatings. STATEMENT OF SIGNIFICANCE: Biomedical devices have severe lubrication modification needs, and surface lubrication modification by polymer brush coating is currently the most promising means. However, the design and preparation of polymer brushes often involves "iterative testing" to find polymer brushes with excellent lubrication properties, which is both time-consuming and expensive. This review proposes a polymer brush development process based on the "design-material selection-preparation-characterization" strategy and summarizes recent research advances and trends in the design, material selection, preparation, and characterization of polymer brushes. This review will help polymer brush researchers by alleviating the challenges of creating polymer brushes with high-performance lubricity and promises to enable the on-demand construction of polymer brush lubrication coatings.


Subject(s)
Molecular Dynamics Simulation , Polymers , Humans , Polymers/chemistry , Prostheses and Implants
10.
Neuroreport ; 35(1): 9-16, 2024 Jan 03.
Article in English | MEDLINE | ID: mdl-37994619

ABSTRACT

Neuroimaging studies have demonstrated the association of the cognitive control network (CCN) with the maintenance of chronic pain. However, whether and how dorsolateral prefrontal cortex (DLPFC), a key region within the CCN, is altered in menstrual pain is unclear. In this study, we aimed to investigate alterations in the DLPFC functional connectivity network in patients with primary dysmenorrhea (PDM). The study comprised 41 PDM patients and 39 matched healthy controls (HCs), all of whom underwent a resting-state functional MRI scan during the menstrual stage. All participants were instructed to complete the clinical assessment before the MRI scan. We used the DLPFC as the seed in resting-state functional connectivity (rsFC) analysis to investigate the difference between PDM patients and HCs. Compared to HCs, PDM patients showed increased right DLPFC rsFC at the bilateral lingual gyrus, dorsal anterior cingulate cortex (dACC), and middle cingulate cortex, and decreased left DLPFC rsFC at the right orbital frontal cortex. In addition, increased right DLPFC-bilateral dACC connectivity mediated the association between disease duration and the self-rating anxiety scale (SAS) scores in PDM patients. We confirmed that the DLPFC-dACC rsFC was associated with higher SAS scores, which could mediate the association between disease duration and anxiety symptoms in patients with PDM. Our findings provide central pathological evidence for an abnormal rsFC of the CCN in PDM patients, which may contribute to a better understanding of the neuropathophysiological mechanisms underlying PDM.


Subject(s)
Brain Mapping , Dysmenorrhea , Female , Humans , Dysmenorrhea/diagnostic imaging , Neural Pathways/diagnostic imaging , Magnetic Resonance Imaging/methods , Anxiety/diagnostic imaging , Cognition
11.
Nanoscale ; 15(46): 18696-18706, 2023 Nov 30.
Article in English | MEDLINE | ID: mdl-37947348

ABSTRACT

Short nanopores have various applications in biosensing, desalination, and energy conversion. Here, the modulation of ionic transport by charged exterior surfaces is investigated through simulations with sub-200 nm long nanopores under applied voltages. Detailed analysis of the ionic current, electric field strength, and fluid flow inside and outside nanopores reveals that charged exterior surfaces can increase ionic conductance by increasing both the concentration and migration speed of charge carriers. The electric double layers near charged exterior surfaces provide an ion pool and an additional passageway for counterions, which lead to enhanced exterior surface conductance and ionic concentrations at pore entrances and inside the nanopores. We also report that charges on the membrane surfaces increase the electric field strength inside nanopores. The effective width of a ring with surface charges placed at pore entrances (Lcs) is considered as well by studying the dependence of the current on Lcs. We find a linear relationship between the effective Lcs and the surface charge density and voltage, and an inverse relationship between the geometrical pore length and salt concentration. Our results elucidate the modulation mechanism of ionic transport through short nanopores by charged exterior surfaces, which is important for the design and fabrication of porous membranes.

12.
ACS Appl Mater Interfaces ; 15(23): 27719-27731, 2023 Jun 14.
Article in English | MEDLINE | ID: mdl-37249568

ABSTRACT

The thrombosis of the extracorporeal circuits leads to serious complications, which affect the life safety of the patients significantly. However, intravenous anticoagulants such as heparin may induce bleeding, hypersensitivity, and other adverse reactions. In this study, the mussel-inspired composite coating consisting of polydopamine (PDAM), lysine, and modified heparin was constructed on the commonly used medical poly(vinyl chloride) (PVC) tubes to reduce thrombosis by combining the immobilization of anticoagulants and the construction of bioinert surface strategies. First, the PDAM/lysine coating rich in amine groups was constructed in a mixed solution of dopamine and lysine through the co-deposition reaction. Then, the modified heparin was covalently immobilized on the PDAM/lysine coating to obtain composite coating. Finally, the graft density and stability of heparin and anticoagulant properties of the composite coating were tested. The results showed that the composite coating could inhibit the adhesion and activation of platelets significantly and prolong the activated partial thromboplastin time (APTT) remarkably for over 25 s. The composite coating also had excellent hemocompatibility, and the hemolysis ratio was less than 0.5%. Particularly, the anticoagulant coating performed well in the in vitro blood circulation test. The composite coating constructed in this work show great potential in the anticoagulant treatment for medical devices.


Subject(s)
Heparin , Thrombosis , Humans , Heparin/pharmacology , Anticoagulants/pharmacology , Lysine , Coated Materials, Biocompatible/pharmacology
13.
Int J Biol Macromol ; 239: 124167, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-36963544

ABSTRACT

Antibacterial hemostatic medical dressings have become feasible solutions in response to the challenging wound-healing process. In this study, a novel fiber-type medical dressing with excellent breathable, antibacterial, and hemostatic qualities was created using sodium alginate (SA), microcrystalline cellulose (MCC), polyvinyl alcohol (PVA), and Euphorbia humifusa Willd (EHW) based on microfluidic spinning technology, and the properties of the dressing were characterized. The orthogonal test demonstrates that PVA and MCC can enhance the mechanical properties of the fiber, which is a crucial requirement for fiber assembly to form the dressing. Moreover, the presence of EHW enhances the dressing's antibacterial and hemostatic qualities. The dressings have been proven to have potent antibacterial and hemostatic properties as well as the ability to considerably speed up wound healing and skin tissue regeneration in the in-vitro and in-vivo tests. In conclusion, this innovative fiber-type medical dressing containing SA, MCC, PVA, and EHW has enormous potential for managing wounds caused by bacteria.


Subject(s)
Euphorbia , Hemostatics , Polyvinyl Alcohol/chemistry , Hemostatics/pharmacology , Microfluidics , Alginates/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Bandages/microbiology
14.
Macromol Biosci ; 23(1): e2200235, 2023 01.
Article in English | MEDLINE | ID: mdl-36239160

ABSTRACT

Accelerating the coagulation process and preventing wound infection are major challenges in the wound care process. Therefore, new multifunctional wound dressings with procoagulant, antibacterial, and antioxidant properties have enormous potential for clinical application. In this work, biodegradable hydrogels containing herbal extracts are prepared for wound dressings. First, the active ingredients are extracted from Amaranthus spinosus (A. spinosus) and Rubia cordifolia (R. cordifolia) and added to the hydrogels prepared from microcrystalline cellulose (MCC), carrageenan, and sodium alginate. Then the composite hydrogels are air-dried to obtain the wound dressings. The wound dressings prepared in this work have good biocompatibility and moisture retention. The mechanical properties of the wound dressings are further improved with the addition of MCC. Besides, the wound dressings have excellent procoagulant, antibacterial, and antioxidant properties due to the presence of R. cordifolia extract. Overall, the most effective group of wound dressings with different ingredient formulations reduces clotting time by 75% and largely inhibits bacterial growth. The wound dressings perform well in the animal wound models to promote wound healing. These results indicate that the hydrogel wound dressings prepared in this work have great potential for medical applications.


Subject(s)
Alginates , Hydrogels , Animals , Carrageenan/pharmacology , Hydrogels/pharmacology , Hydrogels/chemistry , Alginates/pharmacology , Alginates/chemistry , Antioxidants/pharmacology , Antioxidants/chemistry , Wound Healing , Blood Coagulation , Bandages , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Cellulose/pharmacology
15.
Carbohydr Polym ; 297: 120058, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36184154

ABSTRACT

In the field of medical research, the development of safe and effective wound dressings is a continuous goal. Chitosan (CS) is highly sought after because of its unique biocompatibility, biodegradability, antibacterial, and healing-promoting properties. The CS molecule has a significant number of active amino and hydroxyl groups; thus, making substitutions and creating derivatives with varied biochemical properties are relatively straightforward processes. This review addresses the range of functions performed by CS and its derivatives in wound care, such as haemostasis, antibacterial, antioxidant, and wound healing. Furthermore, it summarises the various types of CS-based dressings, their performance features and applications. Finally, the future directions of CS-based dressings are proposed.


Subject(s)
Chitosan , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Bandages , Chitosan/chemistry , Wound Healing
16.
Langmuir ; 38(36): 10994-11002, 2022 Sep 13.
Article in English | MEDLINE | ID: mdl-36048165

ABSTRACT

Phase separation technology has attracted extensive scientific interest because of its intriguing structure changes during the phase separation process. Phase separation inside emulsion droplets in continuous surroundings has been well studied in recent years. Many investigations have also been conducted to study the droplet phase separation phenomena in noncontinuous surroundings. However, studies on the phase separation phenomena and the spreading behavior of suspended droplets at the air-liquid interface were rarely reported. In this study, PEGDA-glycerol suspended Janus droplets with a patchy structure were produced by utilizing solvent evaporation-induced droplet phase separation at the air-liquid interface. By altering the glycerol/PEGDA volume ratio, the initial proportion of ethanol, and the concentration of surfactants, suspended droplets with different morphologies can be achieved, which include filbert-shaped droplets (FSDs), half lotus seedpod single-phase Janus droplets (HLSDs), lotus seedpod single-phase Janus droplets (LSDs), lotus seedpod-shaped droplets (LSSDs), multiple-bulge droplets (MBDs), and half gourd-shaped droplets (HGSDs). A patchy structure was generated at the air-droplet interface, which was attributed to the Marangoni stresses induced by nonuniform evaporation. Furthermore, a modified spreading coefficient theory was constructed and verified to illustrate the phase separation at the air-droplet interface, which was the first research to predict the phase separation phenomena at the air-liquid interface via spreading coefficients theory. Moreover, we studied the factors that led to the droplets being able to float by designing the combined parameters, including three interfacial tensions and the equilibrium contact angles. Therefore, a simple and versatile strategy for creating suspended Janus droplets has been developed for the first time, which holds significant potential in a variety of applications for material synthesis, such as the electrospinning solution behavior when sprayed from the nozzle into the air.

17.
Neurosci Lett ; 788: 136842, 2022 09 25.
Article in English | MEDLINE | ID: mdl-35995304

ABSTRACT

Intracerebral hemorrhage (ICH) is a devastating condition with significant morbidity and mortality for which few effective treatments are clinically available. After ICH, iron overload within the perihaematomal region can induce lethal reactive oxygen species (ROS) production and lipid peroxidation, which contribute to secondary brain injury. An iron-dependent form of non-apoptotic cell death known as ferroptosis was recently identified. Ferroptosis plays an important role in ICH pathology. It is characterized by an accumulation of iron-induced lipid ROS, which leads to intracellular oxidative stress. Dexmedetomidine (DEX), an α2-adrenergic agonist, is widely used for anesthesia, pain control, and intensive care unit sedation. DEX has numerous beneficial activities, including anti-inflammatory, anti-oxidative, and anti-cell death activities. Here, we established a mouse model of ICH using collagenase VII and evaluated the effect of DEX in preventing ICH-induced brain injury. Our study showed that administering DEX reduced the damage induced by ferroptosis after ICH by regulating iron metabolism, amino acid metabolism and lipid peroxidation processes.


Subject(s)
Brain Injuries , Dexmedetomidine , Ferroptosis , Animals , Brain Injuries/metabolism , Brain Injuries/prevention & control , Cerebral Hemorrhage/metabolism , Dexmedetomidine/pharmacology , Dexmedetomidine/therapeutic use , Iron/metabolism , Mice , Reactive Oxygen Species/metabolism
18.
Int J Biol Macromol ; 218: 519-532, 2022 Oct 01.
Article in English | MEDLINE | ID: mdl-35902011

ABSTRACT

Enteromorpha prolifera belonging to the chlorophyta phylum is the main pollutant of "green tide", and propagates rapidly in recent years. However, there is almost no high-value enteromorpha treatment method at present. This study aimed to extract cellulose nanocrystals (CNC) from enteromorpha and prepare the CNC reinforced films based on alginate, carrageenan and shellac for food packaging. The effects of alginate, κ-carrageenan, cellulose nanocrystals and glycerin on the CNC reinforced alginate/carrageenan films (AC films) properties were studied systematically in this work. The results showed that the mechanical properties, swelling properties, and barrier properties of the AC could be adjusted by the concentrations of the different components. In addition, response surface methodology (RSM) was used to optimize the formula of the AC used for food packaging according to the requirements of the practical application. Furthermore, in order to further improve the food packaging capacity of the composite films, shellac was added to the optimized alginate/carrageenan films (OAC films) to obtain the shellac optimized alginate/carrageenan films (SOAC films). Finally, the OAC films and SOAC films showed excellent properties to extend the storage time of chicken breast and cherry tomatoes in the food storage experiment.


Subject(s)
Cellulose , Nanoparticles , Alginates , Carrageenan/chemistry , Cellulose/chemistry , Food Packaging , Nanoparticles/chemistry , Permeability , Resins, Plant
19.
Zhongguo Gu Shang ; 35(7): 688-91, 2022 Jul 25.
Article in Chinese | MEDLINE | ID: mdl-35859383

ABSTRACT

OBJECTIVE: To evaluate the value of D-dimer and common hematological indexes in the preoperative diagnosis of low toxicity infectious bone nonunion. METHODS: Total of 116 cases of bone nonunion from June 2015 to January 2020 were analyzed retrospectively, including 91 males and 25 females;the age ranged from 18 to 65 years old with an average of(45.3±11.2) years old. According to the diagnostic criteria, 116 cases were divided into low toxicity infectious bone nonunion group(31 cases) and aseptic bone nonunion group(85 cases). D-dimer, total leukocyte count, C-reactive protein and erythrocyte sedimentation rate(ESR) were measured at admission, and the differences between two groups were compared. The diagnostic accuracy, sensitivity and specificity were analyzed through the subject working characteristic curve and the area under the curve. RESULTS: All patients were followed up for 12 to 24 months with an average of (11.5±4.3) months. D-dimer, total leukocyte count, C-reactive protein and ESR in low toxicity infectious bone nonunion group were higher than those in aseptic bone nonunion group(P<0.05);compared with other hematological indexes, the area under the curve of D-dimer was the highest, which is 0.826, and the best cut-off value of D-dimer was 1.57 g/L. The sensitivity and specificity of preoperative diagnosis of low toxicity infectious bone nonunion were 78.3% and 84.2%. CONCLUSION: The preoperative diagnostic value of D-dimer in low toxicity infectious bone nonunion is better than other inflammatory indexes. The combination of D-dimer and other inflammatory indexes is conducive to the early diagnosis of low toxicity infectious bone nonunion and the evaluation of the condition.


Subject(s)
C-Reactive Protein , Fibrin Fibrinogen Degradation Products , Adolescent , Adult , Aged , Blood Sedimentation , C-Reactive Protein/analysis , Female , Fibrin Fibrinogen Degradation Products/metabolism , Humans , Male , Middle Aged , Retrospective Studies , Young Adult
20.
Biosensors (Basel) ; 12(5)2022 May 03.
Article in English | MEDLINE | ID: mdl-35624594

ABSTRACT

Microfluidics devices have widely been employed to prepare monodispersed microbubbles/droplets, which have promising applications in biomedical engineering, biosensor detection, drug delivery, etc. However, the current reported microfluidic devices need to control at least two-phase fluids to make microbubbles/droplets. Additionally, it seems to be difficult to make monodispersed microbubbles from the ambient air using currently reported microfluidic structures. Here, we present a facile approach to making monodispersed microbubbles directly from the ambient air by driving single-phase fluid. The reported single-phase-fluid microfluidic (SPFM) device has a typical co-flow structure, while the adjacent space between the injection tube and the collection tube is open to the air. The flow condition inside the SPFM device was systematically studied. By adjusting the flow rate of the single-phase fluid, bubbles were generated, the sizes of which could be tuned precisely. This facile bubble generator may have significant potential as a detection sensor in detecting viruses in spread droplets or haze particles in ambient air.


Subject(s)
Microfluidics , Viruses , Bioengineering , Drug Delivery Systems , Lab-On-A-Chip Devices
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