Publications by authors named "Xiaozhen Ma"

Medical dressings, as a cover for wounds, can replace damaged skin in the wound healing process to play a temporary barrier role, avoid or control wound infection, and provide a favorable environment for wound healing. Therefore, there is an urgent need for medical antimicrobial dressings for the treatment of chronic wounds. Although traditional polyurethane foam has been widely used in medical dressings, conventional polyurethane foams are primarily prepared using nonbiocompatible isocyanate-based compounds, which are potentially hazardous for both operators and applications in the medical field.

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The construction of an effective antibacterial micro-environment to prevent infection and biofilm formation is critically important for the design of wound dressings. Herein, a novel hydrogel wound dressing was fabricated by embedding Au nanoparticles-decorated halloysite nanotubes (Au@HNTs) into the lignin-based hydrogel matrix containing polyvinyl alcohol and chitosan. The resulting composite hydrogel, noted as LPC-Au@HNTs, exhibited an excellent photothermal antibacterial activity owing to the embedded Au@HNTs in which Au nanoparticles were generously filled into the lumen of Halloysite nanotubes.

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Article Synopsis
  • Conventional antibiotics are becoming less effective due to the rise of antibiotic-resistant bacteria, known as "superbugs," prompting the need for new antibacterial solutions.
  • Silver nanoparticles (Ag NPs) are popular for their antimicrobial properties, but their long-term use poses health risks and environmental toxicity, necessitating a reduction in their use.
  • Researchers have developed composite biofoams using polylysine and a minimal amount of Ag NPs that effectively kill bacteria while also promoting wound healing, making them beneficial for treating infected wounds in clinical settings.
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  • The study focuses on creating high-performance, light-sensitive healable, and recyclable covalent adaptable networks from natural lignin-based polyurethane (LPU) using zinc (Zn) coordination.
  • The optimal formulation, LPU-20Z9, achieves enhanced mechanical properties, with a tensile strength of 37.3 MPa and a toughness of 175.4 MJ/m, thanks to the addition of 9 wt% ZnCl.
  • The incorporation of Zn not only improves the material's strength and photothermal capabilities but also facilitates self-healing within 10 minutes and complete recovery in ethanol, paving the way for advanced, sustainable elastomer applications.
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Type 2 diabetes mellitus (T2DM) is characterized by chronic low-grade systemic inflammation. Tissue infiltration by monocyte migration contributes to the pathogenesis of vascular complications in T2DM. We studied the role of intermediate-conductance Ca-activated K (K3.

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Hypothesis: Flotation of water-soluble KCl and NaCl minerals in brines is significant for K-fertilizer production, but its mechanism is controversial. Dissolved salt ions are expected to change the physicochemical properties of solvents, interfaces, and collector colloids, thereby affecting flotation significantly.

Experiments: Flotation experiments of KCl and NaCl crystals in brines were conducted using potassium and sodium laurates as collectors.

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This paper focuses on the effect of fiber orientation on the resistance of seepage-induced erosion in fiber-reinforced sand. To clarify the discrepancy and mechanism of different-oriented fibers improving the resistance of the sand matrix, a series of DEM-Darcy coupling simulations were conducted. The microscopic parameters of fiber-reinforced sand were confirmed by the rigorous calibration procedure.

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Importance: The Sabin-strain inactivated poliovirus vaccine (IPV) may be a tool for polio outbreak response in certain situations.

Objective: To investigate the response to a type 2 vaccine-derived poliovirus (VDPV2) outbreak.

Design, Setting, And Participants: This case series was conducted in China after a VDPV2 was detected in stool specimens from a child with acute flaccid paralysis (AFP) in Sichuan Province in 2019, 3 years after the global withdrawal of live, attenuated type 2 oral poliovirus vaccine (OPV).

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Here a new strategy of catalyst-free direct synthesis of covalent adaptable network polyurethanes (LPUs) from lignin with editable shape memory effect is reported. Using unmodified lignin, PEG, and isocyanate under the condition of the isocyanate index less than 1.0 (NCO/OH<1.

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Article Synopsis
  • * The foam maintains its superhydrophobic properties with minimal change in water contact angle even after extensive compression and abrasion.
  • * Additional benefits include self-cleaning capabilities and rapid degradation in alcoholic alkali solution, making it suitable for industrial wastewater management and oil spill remediation.
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Background: Norovirus is highly diverse and constant surveillance is essential for the prevention and control of norovirus gastroenteritis.

Methods: From 2015 to 2019, fecal samples were collected from sporadic cases and outbreaks of acute gastroenteritis reported to Sichuan center for disease control and prevention. Sewage samples were collected from a wastewater treatment plant in Sichuan.

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Particle-laden interfaces are critical to the flotation separation of hydrophobic particles using air bubbles. After contacting the particle suspension, the bubble surface is loaded with many hydrophobic particles that can get detached during the bubble rise to the top. While many studies of the capillary stability and detachment of single particles from the clean air-water interface have provided significant insights, the particle floatability, detachment, and stability of the particle-laden interface are not well quantified.

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Antimicrobial materials are an urgent need for modern wound care in the clinic. Although traditional polyurethane foams have proven to be clinically valuable for wound treatment, their petroleum-originated preparation and bioinert nature have restricted their efficacy in biomedical applications. Here, we propose a simple one-step foaming method to prepare lignin-based polyurethane foams (LPUFs) in which fully biobased polyether polyols partially replace traditional petroleum-based raw materials.

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Background: China implemented the globally synchronized switch from trivalent oral poliovirus vaccine (tOPV) to bivalent OPV (bOPV) on May 1, 2016. During April 2018 to May 2019, the first outbreak caused by type 2 circulating vaccine-derived poliovirus (cVDPV2) after the switch occurred in Xinjiang and Sichuan, China. We performed sequence analysis of VP1 and the whole genome to determine the genomic characteristics of type 2 cVDPVs, and carried out coverage surveys to assess the risk of viral propagation.

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Objectives: Norovirus is associated with one-fifth of all gastroenteritis cases, but basic epidemiological data is lacking, especially in developing countries. As long-term surveillance on norovirus gastroenteritis is scarce in western China, this study aims to update the epidemiological knowledge of norovirus gastroenteritis and to characterize the genotypes of norovirus strains.

Methods: Stool samples were collected from hospitalized children under 5 years old with gastroenteritis in Chengdu, China.

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Polyurethane (PU), as a polymer material with versatile product forms and excellent performance, is used in coatings, elastomers, adhesives, and foams widely. However, the raw materials (polyols and isocyanates) of PU are usually made using petroleum-derived chemicals. With the concern for depletion of petroleum resources and the associated negative impact on the environment, developing technologies that can use renewable raw materials as feedstock has become a research hotspot.

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The opening of endothelial small-conductance calcium-activated potassium channels (K2.3) is essential for endothelium-dependent hyperpolarization (EDH), which predominantly occurs in small resistance arteries. Adenosine monophosphate-activated protein kinase (AMPK), an important metabolic regulator, has been implicated in regulating endothelial nitric oxide synthase activity.

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What Is Already Known About This Topic?: After the type 2 strain of the live, attenuated poliovirus vaccine was withdrawn globally in 2016, any identification of a type 2 poliovirus is a Public Health Emergency of International Concern. A vaccine-derived type 2 poliovirus (VDPV2) was identified in Sichuan, prompting an urgent, comprehensive investigation and response.

What Is Added By This Report?: Type 2 monovalent, live, attenuated oral poliovirus vaccine (mOPV2) is being used to respond to the numerous VDPV2 outbreaks seen around the world.

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MicroRNAs (miRNAs) have emerged as crucial regulators of neuronal injury during cerebral ischaemia/reperfusion injury. Various miRNAs are dysregulated during this pathological process; however, the precise role of these miRNAs in regulating neuronal injury remains largely unknown. In the current study, we explored the potential function of microRNA-148b-3p (miR-148b-3p) in regulating neuronal injury induced by oxygen-glucose deprivation/reoxygenation (OGD/R) in vitro, a cellular model for mimicking cerebral ischaemia/reperfusion injury.

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Chronic islet inflammation is associated with development of type 2 diabetes mellitus (T2DM). Intermediate-conductance calcium-activated K (K3.1) channel plays an important role in inflammatory diseases.

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Capillary force is critical to the floatability of particles at the air-water interface. Quantification of the capillary force requires solving the Young-Laplace equation using suitable boundary conditions (BCs) at the triple contact line. For axisymmetric (two-dimensional, 2D) systems, such as single spheres floating at an initially flat air-water surface, both the Dirichlet (constant contact depth) and Neumann (constant contact angle) BCs can be applied.

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Monocyte migration into diseased tissues contributes to the pathogenesis of diseases. Intermediate-conductance Ca-activated K (K3.1) channels play an important role in cell migration.

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The intermediate-conductance Ca(2+)-activated K(+) (KCa3.1) channels play a pivotal role in the proliferation and collagen secretion of cardiac fibroblasts. However, their contribution in cardiac fibrosis remains unknown.

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Background: During August 2011-February 2012, an outbreak of type Π circulating vaccine-derived poliovirus (cVDPVs) occurred in Sichuan Province, China.

Methods: A field investigation of the outbreak was conducted to characterize outbreak isolates and to guide emergency response. Sequence analysis of poliovirus capsid protein VP1 was performed to determine the viral propagation, and a coverage survey was carried out for risk assessment.

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