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Small (Weinheim An Der Bergstrasse,... Apr 2024Chronic wounds constitute an increasingly prevalent global healthcare issue, characterized by recurring bacterial infections, pronounced oxidative stress, compromised...
Chronic wounds constitute an increasingly prevalent global healthcare issue, characterized by recurring bacterial infections, pronounced oxidative stress, compromised functionality of immune cells, unrelenting inflammatory reactions, and deficits in angiogenesis. In response to these multifaceted challenges, the study introduced a stimulus-responsive glycopeptide hydrogel constructed by oxidized Bletilla striata polysaccharide (OBSP), gallic acid-grafted ε-Polylysine (PLY-GA), and paeoniflorin-loaded micelles (MIC@Pae), called OBPG&MP. The hydrogel emulates the structure of glycoprotein fibers of the extracellular matrix (ECM), exhibiting exceptional injectability, self-healing, and biocompatibility. It adapts responsively to the inflammatory microenvironment of chronic wounds, sequentially releasing therapeutic agents to eradicate bacterial infection, neutralize reactive oxygen species (ROS), modulate macrophage polarization, suppress inflammation, and encourage vascular regeneration and ECM remodeling, playing a critical role across the inflammatory, proliferative, and remodeling phases of wound healing. Both in vitro and in vivo studies confirmed the efficacy of OBPG&MP hydrogel in regulating the wound microenvironment and enhancing the regeneration and remodeling of chronic wound skin tissue. This research supports the vast potential for herb-derived multifunctional hydrogels in tissue engineering and regenerative medicine.
PubMed: 38686688
DOI: 10.1002/smll.202400516 -
Nature Communications Apr 2024Biomolecular condensates play an important role in cellular organization. Coacervates are commonly used models that mimic the physicochemical properties of biomolecular...
Biomolecular condensates play an important role in cellular organization. Coacervates are commonly used models that mimic the physicochemical properties of biomolecular condensates. The surface of condensates plays a key role in governing molecular exchange between condensates, accumulation of species at the interface, and the stability of condensates against coalescence. However, most important surface properties, including the surface charge and zeta potential, remain poorly characterized and understood. The zeta potential of coacervates is often measured using laser doppler electrophoresis, which assumes a size-independent electrophoretic mobility. Here, we show that this assumption is incorrect for liquid-like condensates and present an alternative method to study the electrophoretic mobility of coacervates and in vitro condensate models by microelectrophoresis and single-particle tracking. Coacervates have a size-dependent electrophoretic mobility, originating from their fluid nature, from which a well-defined zeta potential is calculated. Interestingly, microelectrophoresis measurements reveal that polylysine chains are enriched at the surface of polylysine/polyaspartic acid complex coacervates, which causes the negatively charged protein ɑ-synuclein to adsorb and accumulate at the interface. Addition of ATP inverts the surface charge, displaces ɑ-synuclein from the surface and may help to suppress its interface-catalyzed aggregation. Together, these findings show how condensate surface charge can be measured and altered, making this microelectrophoresis platform combined with automated single-particle tracking a promising characterization technique for both biomolecular condensates and coacervate protocells.
Topics: Electrophoresis; Surface Properties; Biomolecular Condensates; alpha-Synuclein; Polylysine; Adenosine Triphosphate; Humans; Static Electricity
PubMed: 38670952
DOI: 10.1038/s41467-024-47885-2 -
Analytical Chemistry Nov 2023Plyfluoroalkyl substance (PFAS), featured with incredible persistence and chronic toxicity, poses an emerging ecological and environmental crisis. Although significant...
Plyfluoroalkyl substance (PFAS), featured with incredible persistence and chronic toxicity, poses an emerging ecological and environmental crisis. Although significant progress has been made in PFAS metabolism in vivo, the underlying mechanism of metabolically active organ interactions in PFAS bioaccumulation remains largely unknown. We developed a microfluidic-based assay to recreate the intestine-vessel-liver interface in three dimensions, allowing for high-resolution, real-time images and precise quantification of intestine-vessel-liver interactions in PFAS biotransformation. In contrast to the scattered arrangement of vascular endothelium on the traditional d-polylysine-modified two-dimensional (2D) plate, the microtubules in our three-dimensional (3D) platform formed a dense honeycomb network through the ECM, with longer tubular structures. Additionally, the slope culture of epithelial cells in our platform exhibited a closely arranged and thicker cell layer than the planar culture. To dynamically monitor the metabolic crosstalk in the intestinal-vascular endothelium-liver interaction under exposure to fluorotelomer alcohols (FTOHs), we combined the chip with a solid-phase extraction-mass spectrometry (SPE-MS) system. Our findings revealed that endothelial cells were involved in the metabolic process of FTOHs. The transformation of intestinal epithelial and hepatic epithelial cells produces toxic metabolite fluorotelomer carboxylic acids (FTCAs), which circulate to endothelial cells and affect angiogenesis. This system shows promise as an enhanced surrogate model and platform for studying pollutant exposure as well as for biomedical and pharmaceutical research.
Topics: Endothelial Cells; Microfluidics; Fluorocarbons; Biotransformation; Liver
PubMed: 37943962
DOI: 10.1021/acs.analchem.3c03892 -
Food Chemistry Dec 2023To develop food packaging with good antibacterial activity and mechanical performance, four amino carboxymethyl chitosan (ACC)//dialdehyde starch (DAS) /polyvinyl...
To develop food packaging with good antibacterial activity and mechanical performance, four amino carboxymethyl chitosan (ACC)//dialdehyde starch (DAS) /polyvinyl alcohol (PVA) films were prepared by Schiff base and hydrogen bond interactions for efficient loading and release of ε-polylysine (ε-PL). The effects of the Schiff base reaction on the physicochemical properties of the films were explored based on the different aldehyde group contents in DAS. The ACC//DAS/PVA film exhibited a tensile strength of 62.5 MPa, and the water vapor and oxygen permeability was 8.77 × 10·g·mm/m·d·kPa and 0.15 × 10·cm·mm/m·d, respectively. By leveraging the Schiff base reaction, the film swelling properties were improved by adjusting the cross-link density, mesh size, and molecular mass between the cross-links. The ACC//DAS/PVA film could efficiently load ε-PL with a value of 98.44% and long-term release in a food simulant of 10% ethanol at 25 °C for 120 min. Moreover, the ACC-ε-PL//DAS/PVA film was successfully used for salmon preservation.
Topics: Chitosan; Polyvinyls; Polyvinyl Alcohol; Polylysine; Schiff Bases; Anti-Bacterial Agents; Food Packaging
PubMed: 37423111
DOI: 10.1016/j.foodchem.2023.136775 -
Molecules (Basel, Switzerland) Jul 2023The aim of the present study was to develop an injectable hydrogel (HG) formulation of fuzapladib sodium (FZP), an animal drug for acute pancreatitis (AP), with the use...
The aim of the present study was to develop an injectable hydrogel (HG) formulation of fuzapladib sodium (FZP), an animal drug for acute pancreatitis (AP), with the use of polyethyleneoxide (PEO) and polylysine (pLys), a cationic polymer. A mixture of pLys and FZP was added to PEO to prepare an HG formulation, and the formulation was optimized by release test and viscosity measurements. Circular dichroism (CD) and infrared absorption (IR) spectral analyses were applied to clarify the intermolecular interactions between FZP and pLys. The pharmacokinetic behavior of FZP was evaluated after a subcutaneous administration of FZP samples (2.0 mg-FZP/kg) to rats. Although the immediate release of FZP was observed for the HG formulation, the addition of pLys at a 20-fold amount of FZP or higher led to the sustained release of FZP. Considering release behavior, the concentration of pLys was optimized as 100-fold that of FZP in the HG formulation. CD and IR spectroscopic analyses of FZP and/or pLys demonstrated an intermolecular interaction between FZP and pLys, as evidenced by the slight spectral transition. After a subcutaneous administration of HG formulation containing pLys to rats, compared with FZP alone, significant differences were observed in the pharmacokinetic behavior with a decrease of from 2.3 to 0.9 mg/mL and slower elimination kinetics. HG formulation using pLys might be a viable dosage option for FZP for the treatment of AP in animals.
Topics: Rats; Animals; Polylysine; Hydrogels; Delayed-Action Preparations; Lymphocyte Function-Associated Antigen-1; Acute Disease; Pancreatitis; Leukocytes
PubMed: 37513199
DOI: 10.3390/molecules28145325 -
The Journal of Allergy and Clinical... Nov 2023Skin testing is an important step in evaluation of penicillin allergic reactions. It includes testing to the following: amoxicillin, benzyl penicillin, and products...
BACKGROUND
Skin testing is an important step in evaluation of penicillin allergic reactions. It includes testing to the following: amoxicillin, benzyl penicillin, and products generated after penicillin administration, the major determinant hapten penicilloyl-polylysine (PPL) and the minor determinant mixture (MDM). Although PPL and MDM are available as a commercial kit, their supply and cost remain problematic.
OBJECTIVE
We aimed to evaluate the performance and utility of PPL and MDM in penicillin allergy testing.
METHODS
A retrospective audit over a 5-year period was undertaken for those with penicillin testing in a tertiary immunology unit.
RESULTS
In all, 214 patients were identified. Of those patients, 151 (70.6%) were female and the average age was 58 years. Unspecified penicillin was the most common index drug (n = 127 [59.3%]), followed by amoxicillin (n =3 [24.8%]) and amoxicillin-clavulanic acid (n = 21 [9.7%]). The result of skin testing was positive in 23 patients (10.7%); skin prick testing was positive in 10 patients (4.7%), and intradermal testing (IDT) was positive in 13 patients (6.1%), the majority of whom had identified amoxicillin or amoxicillin-clavulanic acid as the index drug (n = 22 [95.7%]). The result of testing to PPL and/or MDM was positive with IDT only (n=5 [23.8%]). PPL and MDM positivity coexisted with a positive reaction to amoxicillin IDT in 2 patients, 1 of whom passed an amoxicillin challenge. Additionally, 2 positive tests to PPL were present with a negative result for MDM; of these 2 positive results, 1 was positive to amoxicillin IDT. In only 1 case were the results of testing for MDM and PPL both positive, with negative results to all native β-lactams tested; the patient tolerated an amoxicillin challenge. Overall, the negative predictive value for both skin prick testing and IDT was 89.5%.
CONCLUSION
Benzyl penicillin and amoxicillin alone may be sufficient for testing in suspected individuals with penicillin allergy.
PubMed: 37781672
DOI: 10.1016/j.jacig.2023.100132 -
International Journal of Biological... Jul 2023In the past decades, the microencapsulation of mammalian cells into microparticles has been extensively studied for various in vitro and in vivo applications. The aim of...
In the past decades, the microencapsulation of mammalian cells into microparticles has been extensively studied for various in vitro and in vivo applications. The aim of this study was to demonstrate the viability of bacterial polyglucuronic acid (PGU), an exopolysaccharide derived from bacteria and composed of glucuronic acid units, as an effective material for cell microencapsulation. Using the method of dropping an aqueous solution of PGU-containing cells into a Ca-loaded solution, we produced spherical PGU microbeads with >93 % viability of the encapsulated human hepatoma HepG2 cells. Hollow-core microcapsules were formed via polyelectrolyte complex layer formation of PGU and poly-l-lysine, after which Ca, a cross-linker of PGU, was chelated, and this was accomplished by sequential immersion of microbeads in aqueous solutions of poly-l-lysine and sodium citrate. The encapsulated HepG2 cells proliferated and formed cell aggregates within the microparticles over a 14-day culture, with significantly larger aggregates forming within the microcapsules. Our results provide evidence for the viability of PGU for cell microencapsulation for the first time, thereby contributing to advancements in tissue engineering.
Topics: Animals; Humans; Capsules; Polylysine; Microspheres; Tissue Engineering; Alginates; Glucuronic Acid; Hexuronic Acids; Mammals
PubMed: 37343612
DOI: 10.1016/j.ijbiomac.2023.125481 -
Foods (Basel, Switzerland) Oct 2023In this paper, amino-carboxymethyl chitosan (ACC) was prepared through amino carboxymethylation, which introduces -COOH and -NH groups to the chitosan (CS) chains....
In this paper, amino-carboxymethyl chitosan (ACC) was prepared through amino carboxymethylation, which introduces -COOH and -NH groups to the chitosan (CS) chains. Meanwhile, dialdehyde starch (DAS) was produced by oxidizing corn starch using sodium periodate. To attain the optimal loading and long-time release of ε-polylysine (ε-PL), the ACC/DAS hydrogels were synthesized through the Schiff base reaction between the amino group on ACC and the aldehyde group in DAS. The molecular structure, microcosmic properties, loading capacity, and bacteriostatic properties of the four types of hydrogels containing different mass concentrations of ACC were investigated. The results showed that the dynamic imine bond C=N existed in the ACC/DAS hydrogels, which proved that the hydrogels were formed by the cross-linking of the Schiff base reaction. With the increasing mass concentration of the ACC, the cross-sectional morphology of the hydrogel became smoother, the thermal stability increased, and the swelling behavior was gradually enhanced. The tight network structure improved the ε-PL loading efficiency, with the highest value of 99.2%. Moreover, the loading of ε-PL gave the hydrogel good antibacterial properties. These results indicate that ACC/DAS hydrogel is potential in food preservation.
PubMed: 37893700
DOI: 10.3390/foods12203807 -
Revista Alergia Mexico (Tecamachalco,... Sep 2023The most commonly reported antibiotic allergy is penicillin. The false label of "allergy" to penicillin negatively affects the patient's quality of life and medical care. (Observational Study)
Observational Study
BACKGROUND
The most commonly reported antibiotic allergy is penicillin. The false label of "allergy" to penicillin negatively affects the patient's quality of life and medical care.
OBJECTIVE
To determine the frequency of allergy to penicillin and amoxicillin by in vivo exposure tests in patients with a history of immediate reaction to this class of medicinal products.
METHODS
Observational, cross-sectional, descriptive and prolective study in patients between 12 and 60 years of age with a history of immediate reaction to penicillin and/or amoxicillin. Prick and intradermal skin tests were performed with benzylpenicilloyl polylysine (Pre-Pen), penicillin G and oral challenge test with amoxicillin. The frequency of positivity and negativity in these tests was calculated with a 95% CI. Results were analyzed in Epi info 7.2.5.0.
RESULTS
In total 13 patients (10 women) were included, with a mean age of 39 years (SD 12.14). In 84.6% the last adverse drug reaction occurred 10 years ago and in all manifested with urticaria. The 38.4% confirmed penicillin allergy and the most frequent adverse reaction after in vivo tests was pruritus.
CONCLUSIONS
The clinical history alone is not sufficient, all patients with suspected penicillin allergy should be evaluated by in vivo exposure tests with major and minor determinants to corroborate or rule out allergy to this pharmacological class.
Topics: Adult; Female; Humans; Amoxicillin; Anti-Bacterial Agents; Cross-Sectional Studies; Drug Hypersensitivity; Penicillins; Quality of Life; Skin Tests; Urticaria; Male; Child; Adolescent; Young Adult; Middle Aged
PubMed: 37933946
DOI: 10.29262/ram.v70i3.1254 -
International Journal of Biological... Dec 2023To address the environmental and food contamination issues caused by plastics and microorganisms, antimicrobial films using natural polymers has attracted enormous...
To address the environmental and food contamination issues caused by plastics and microorganisms, antimicrobial films using natural polymers has attracted enormous attention. In this work, we proposed a green, convenient and fast approach to prepare antimicrobial films from chitosan (CS), bacterial cellulose (BC) and ε-polylysine (ε-PL). The effects of different concentrations of ε-PL (0 %, 0.25 %, 0.5 %, 0.75 %, 1 %, w/v) on the physicochemical properties and antibacterial activity of composite films (CS-DABC-x%PL) were systematically investigated. Furthermore, a comprehensive comparison with purely physically mixed CS-BC-x%PL films provides a deeper understanding of the subject matter. Characterization tests of the films were conducted using scanning electron microscope (SEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The results suggested that the incorporation of 0.5 % ε-PL reduced the water solubility of the composite film by 19.82 %, along with improved the tensile strength and thermal stability by 37.31 % and 28.54 %. As ε-PL concentration increased to 1 %, the antibacterial performance of the films gradually enhanced. Additionally, the CS-DABC-0.5%PL film demonstrated effectiveness in delaying the deterioration of tilapia. These findings imply that this novel green packaging material holds significant potential in food preservation due to its promising antibacterial properties.
Topics: Chitosan; Cellulose; Polylysine; Food Packaging; Anti-Bacterial Agents; Anti-Infective Agents; Food Preservation
PubMed: 37804899
DOI: 10.1016/j.ijbiomac.2023.127231