F127-SE-tLAP thermosensitive hydrogel alleviates bleomycin-induced skin fibrosis via TGF-ß/Smad pathway.

BACKGROUND: Skin fibrosis affects the normal function of the skin. TGF-ß1 is a key cytokine that affects organ fibrosis. The latency-associated peptide (LAP) is essential for TGF-ß1 activation. We previously constructed and prepared truncated LAP (tLAP), and confirmed that tLAP inhibited liver fibrosis by affecting TGF-ß1. SPACE peptide has both transdermal and transmembrane functions. SPACE promotes the delivery of macromolecules through the stratum corneum into the dermis. This study aimed to alleviate skin fibrosis through the delivery of tLAP by SPACE. METHODS: The SPACE-tLAP (SE-tLAP) recombinant plasmid was constructed. SE-tLAP was purified by nickel affinity chromatography. The effects of SE-tLAP on the proliferation, migration, and expression of fibrosis-related and inflammatory factors were evaluated in TGF-ß1-induced NIH-3T3 cells. F127-SE-tLAP hydrogel was constructed by using F127 as a carrier to load SE-tLAP polypeptide. The degradation, drug release, and biocompatibility of F127-SE-tLAP were evaluated. Bleomycin was used to induce skin fibrosis in mice. HE, Masson, and immunohistochemistry were used to observe the skin histological characteristics. RESULTS: SE-tLAP inhibited the proliferation, migration, and expression of fibrosis-related and inflammatory factors in NIH-3T3 cells. F127-SE-tLAP significantly reduced ECM production, collagen deposition, and fibrotic pathological changes, thereby alleviating skin fibrosis. CONCLUSION: F127-SE-tLAP could increase the transdermal delivery of LAP, reduce the production and deposition of ECM, inhibit the formation of dermal collagen fibers, and alleviate the progression of skin fibrosis. It may provide a new idea for the therapy of skin fibrosis.

Dual Contributions of Analyte Adsorption and Electroosmotic Inhomogeneity to Separation Efficiency in Capillary Electrophoresis of Proteins.

Improving separation efficiency in capillary electrophoresis (CE) requires systematic study of the influence of the electric field (or solute linear velocity) on plate height for a better understanding of the critical parameters controlling peak broadening. Even for poly(diallyldimethylammonium chloride) (PDADMAC)/poly(sodium styrenesulfonate) (PSS) successive multiple ionic-polymer layer (SMIL) coatings, which lead to efficient and reproducible separations of proteins, plate height increases with migration velocity, limiting the use of high electric fields in CE. Solute adsorption onto the capillary wall was generally considered as the main source of peak dispersion, explaining this plate height increase. However, experiments done with Taylor dispersion analysis and CE in the same conditions indicate that other phenomena may come into play. Protein adsorption with slow kinetics and few adsorption sites was established as a source of peak broadening for specific proteins. Surface charge inhomogeneity was also identified as a contribution to plate height due to local electroosmotic fluctuations. A model was proposed and applied to partial PDADMAC/poly(ethylene oxide) capillary coatings as well as PDADMAC/PSS SMIL coatings. Atomic force microscopy with topography and recognition imaging enabled the determination of roughness and charge distribution of the PDADMAC/PSS SMIL surface.

Membrane-Free Lateral Flow Assay with the Active Control of Fluid Transport for Ultrasensitive Cardiac Biomarker Detection.

Membrane-based lateral flow immunoassays (LFAs) have been employed as early point-of-care (POC) testing tools in clinical settings. However, the varying membrane properties, uncontrollable sample transport in LFAs, visual readout, and required large sample volumes have been major limiting factors in realizing needed sensitivity and desirable precise quantification. Addressing these challenges, we designed a membrane-free system in which the desirable three-dimensional (3D) structure of the detection zone is imitated and used a small pump for fluid flow and fluorescence as readout, all the while maintaining a one-step assay protocol. A hydrogel-like protein-polyelectrolyte complex (PPC) within a polyelectrolyte multilayer (PEM) was developed as the test line by complexing polystreptavidin (pSA) with poly(diallyldimethylammonium chloride) (PDDA), which in turn was layered with poly(acrylic acid) (PAA) resulting in a superior 3D streptavidin-rich test line. Since the remainder of the microchannel remains material-free, good flow control is achieved, and with the total volume of 20 µL, 7.5-fold smaller sample volumes can be used in comparison to conventional LFAs. High sensitivity with desirable reproducibility and a 20 min total assay time were achieved for the detection of NT-proBNP in plasma with a dynamic range of 60-9000 pg·mL-1 and a limit of detection of 56 pg·mL-1 using probe antibody-modified fluorescence nanoparticles. While instrument-free visual detection is no longer possible, the developed lateral flow channel platform has the potential to dramatically expand the LFA applicability, as it overcomes the limitations of membrane-based immunoassays, ultimately improving the accuracy and reducing the sample volume so that finger-prick analyses can easily be done in a one-step assay for analytes present at very low concentrations.

Irradiation Behavior of Analgesic and Nonsteroidal Anti-Inflammatory Drug-Loaded UHMWPE for Joint Replacement.

Local delivery of pain medication can be a beneficial strategy to address pain management after joint replacement, as it can decrease systemic opioid usage, leading to less side and long-term effects. In this study, we used ultrahigh molecular weight polyethylene (UHMWPE), commonly employed as a bearing material for joint implants, to deliver a wide set of analgesics and the nonsteroidal anti-inflammatory drug tolfenamic acid. We blended the drugs with UHMWPE and processed the blend by compression molding and sterilization by low-dose gamma irradiation. We studied the chemical stability of the eluted drugs, drug elution, tensile properties, and wear resistance of the polymer blends before and after sterilization. The incorporation of bupivacaine hydrochloride and tolfenamic acid in UHMWPE resulted in either single- or dual-drug loaded materials that can be sterilized by gamma irradiation. These compositions were found to be promising for the development of clinically relevant drug-eluting implants for joint replacement.

Pluronic F127-Lipoic Acid Adhesive Nanohydrogel Combining with Ce3+/Tannic Acid/Ulinastatin Nanoparticles for Promoting Wound Healing.

Developing strong anti-inflammatory wound dressings is of great significance for protecting inflammatory cutaneous wounds and promoting wound healing. The present study develops a nanocomposite Pluronic F127 (F127)-based hydrogel dressing with injectable, tissue adhesive, and anti-inflammatory performance. Briefly, Ce3+/tannic acid/ulinastatin nanoparticles (Ce3+/TA/UTI NPs) are fabricated. Meanwhile, α-lipoic acid is bonded to the ends of F127 to prepare F127-lipoic acid (F127LA) and its nanomicelles. Due to the gradual viscosity change instead of mutation during phase transition, the mixed Ce3+/TA/UTI NPs and F127LA nanomicelles show well-performed injectability at 37 °C and can form a semisolid composite nanohydrogel that can tightly attach to the skin at 37 °C. Furthermore, ultraviolet (UV) irradiation without a photoinitiator transforms the semisolid hydrogel into a solid hydrogel with well-performed elasticity and toughness. The UV-cured composite nanohydrogel acts as a bioadhesive that can firmly adhere to tissues. Due to the limited swelling property, the hydrogel can firmly adhere to tissues in a wet environment, which can seal wounds and provide a reliable physical barrier for the wounds. Ce3+/TA/UTI NPs in the hydrogel exhibit lipopolysaccharide (LPS)-scavenging ability and reactive oxygen species (ROS)-scavenging ability and significantly reduce the expression of inflammatory factors in wounds at the early stage, accelerating LPS-induced wound healing.

Structural and therapeutic properties of salicylic acid-solubilized Pluronic solutions and hydrogels.

Salicylic acid (SA) finds extensive applications in the treatment of rheumatic and skin diseases because of its analgesic, anti-inflammatory and exfoliating properties. As it is lipophilic in nature, there is a need for appropriate delivery systems to harness these properties for different applications. Herein, we examined the suitability of Pluronic P123/F127 micellar systems as delivery media by investigating the structural, flow and antimicrobial properties of P123/F127-SA solutions and hydrogels using DLS, SANS, rheological and zone inhibition measurement techniques. SA modulates the aggregation characteristics of these surfactant systems and brings about spherical-to-worm-like micelle-to-vesicular structural transitions in the hydrophobic Pluronic P123 system, a spherical-to-worm-like micellar transition in the mixed P123/F127 system and an onset of inter-micellar attraction in the hydrophilic Pluronic F127 system. SA-solubilized systems of both hydrophobic and hydrophilic Pluronics inhibit the growth of Gram-positive and Gram-negative bacteria with comparable MIC values. This suggests that the interaction of SA molecules with the bacterial cell membrane remains unobstructed upon encapsulation in Pluronic micelles. F127 hydrogel-based SA formulations with rheological properties suitable for topical applications and up to 15% SA loading were prepared. These will be useful SA ointments as F127 is an FDA-approved excipient for topical drug delivery applications. The results indicate that Pluronics remain effective as delivery agents for SA and exhibit interesting structural polymorphism upon its solubilization.

Identification of Additives in Disposable Face Masks and Evaluation of Their Toxicity Using Marine Medaka (Oryzias melastigma).

The COVID-19 pandemic has resulted in huge amounts of face masks worldwide. However, there is a lack of awareness on the additives and their potential risk to aquatic ecosystems of face masks. To address this issue, the additives and their toxicity in 13 face masks (e.g., polypropylene, polyethylene, and polylactic acid) were determined using nontarget analysis and bioassays. A total of 826 organic additives including intermediates (14.8%), surfactants (9.3%), plasticizers (8.2%), and antioxidants (6.1%) were tentatively identified, with 213 compounds being assigned confidence levels of 1 and 2. Interestingly, polylactic acid masks contained more additives than most polypropylene or polyethylene masks. Among these additives, the concentration of tris(2-ethylhexyl) phosphate in masks was 9.4-978.2 ng/g with a 100% detection frequency. Furthermore, 13 metals such as zinc (up to 202.0 µg/g), copper (32.5 µg/g), and chromium (up to 5.7 µg/g) were detected in the face masks. The methanol extracts of the masks showed the developmental toxicity, swimming behavior, and/or endocrine disruption in embryos/larvae of Oryzias melastigma. The findings demonstrate that face masks contain various toxic additives to marine medaka, which deserves close attention to pollution by face masks.

The Isothermal Melting Kinetics of Ultra-High Molecular Weight Polyethylene Crystals.

The isothermal melting behaviors of ultra-high molecular weight polyethylene (UHMWPE) with different entangled states (i.e., nascent and melt-crystallized samples) are studied. For two kinds of UHMWPE samples, the result shows that the relative content of survived crystals (Xs) exponentially decreases with time and reaches a constant value. It is suggested that such a melting behavior is related to the observed nonlinear growth of crystals induced by the kinetically rejected entanglements accumulated at the growth front. Additionally, the exponential decay of Xs with time provides a characteristic melting time (τ) for the melting process. Compared to the melt-crystallized UHMWPE, the τ value of nascent UHMWPE is generally longer even in a higher temperature range, which is mainly because the former has a larger entanglement density difference. Furthermore, these observations demonstrate that UHMWPEs with different entangled states have an analogous melting mechanism since they exhibit a similar melting activation energy (≈1300 kJ mol-1).

Stress analysis of horizontal mid-root fracture managed with different intraradicular fixation protocols: A 3D-finite element study.

The current study evaluated the stress distribution in a maxillary central incisor with mid-root fracture after splinting with different intra-radicular posts using 3D-finite element analysis (FEA). Five 3D-FEA models were constructed. Model 1 was an intact tooth with no fracture, Model 2: A tooth with a horizontal mid-root fracture, with no treatment. Model 3: Same as model 2, and intraradicular splinting using fiber post. Model 4: Same as model 2 and intra-radicular splinting using Protaper Gold file F3. Model 5: Same as model 2, and with intraradicular splinting with Ribbond. The FEA of all models was done to obtain the maximum Von-Mises stress in the root canal space, the dentin, the periodontal ligament, and the bone. The highest Von Mises stresses for the root canal space and the dentin were found in Model 3, followed by models 4, 5, and 2, and least in Model 1. The Von Mises stress of the periodontal ligament was the least in model 1. The Von Mises stress of bone was higher in all experimental models than in the baseline model. The results suggest that in cases where intra-radicular splinting is indicated, fiber posts and Ribbond are better alternatives to endodontic files due to the lower stresses exerted.

Sleep deprivation boosts O2·- levels in the brains of mice as visualized by a Golgi apparatus-targeted ratiometric fluorescence nanosensor.

Sleep deprivation (SD) is highly prevalent in the modern technological world. Emerging evidence shows that sleep deprivation is associated with oxidative stress. At the organelle level, the Golgi apparatus actively participates in the stress response. In this study, to determine whether SD and Golgi apparatus stress are correlated, we rationally designed and fabricated a novel Golgi apparatus-targeted ratiometric nanoprobe called Golgi dots for O2·- detection. This probe exhibits high sensitivity and selectivity in cells and brain slices of sleep-deprived mice. Golgi dots can be readily synthesized by coprecipitation of Golgi-F127, an amphiphilic polymer F127 modified with a Golgi apparatus targeting moiety, caffeic acid (CA), the responsive unit for O2·-, and red emissive carbon nanodots (CDs), which act as the reference signal. The fluorescence emission spectrum of the developed nanoprobe showed an intense peak at 674 nm, accompanied by a shoulder peak at 485 nm. As O2·- was gradually added, the fluorescence at 485 nm continuously increased; in contrast, the emission intensity at 674 nm assigned to the CDs remained constant, resulting in the ratiometric sensing of O2·-. The present ratiometric nanoprobe showed high selectivity for O2·- monitoring due to the specific recognition of O2·- by CA. Moreover, the Golgi dots exhibited good linearity with respect to the O2·- concentration within 5 to 40 µM, and the limit of detection (LOD) was ~ 0.13 µM. Additionally, the Golgi dots showed low cytotoxicity and an ability to target the Golgi apparatus. Inspired by these excellent properties, we then applied the Golgi dots to successfully monitor exogenous and endogenous O2·- levels within the Golgi apparatus. Importantly, with the help of Golgi dots, we determined that SD substantially elevated O2·- levels in the brain.

Effect of vitamin E-enhanced highly cross-linked polyethylene on wear rate and particle debris in anatomic total shoulder arthroplasty: a biomechanical comparison to ultrahigh-molecular-weight polyethylene.

BACKGROUND: Particle-induced osteolysis resulting from polyethylene wear remains a source of implant failure in anatomic total shoulder designs. Modern polyethylene components are irradiated in an oxygen-free environment to induce cross-linking, but reducing the resulting free radicals with melting or heat annealing can compromise the component's mechanical properties. Vitamin E has been introduced as an adjuvant to thermal treatments. Anatomic shoulder arthroplasty models with a ceramic head component have demonstrated that vitamin E-enhanced polyethylene show improved wear compared with highly cross-linked polyethylene (HXLPE). This study aimed to assess the biomechanical wear properties and particle size characteristics of a novel vitamin E-enhanced highly cross-linked polyethylene (VEXPE) glenoid compared to a conventional ultrahigh-molecular-weight polyethylene (UHMWPE) glenoid against a cobalt chromium molybdenum (CoCrMo) head component. METHODS: Biomechanical wear testing was performed to compare the VEXPE glenoid to UHMWPE glenoid with regard to pristine polyethylene wear and abrasive endurance against a polished CoCrMo alloy humeral head in an anatomic shoulder wear-simulation model. Cumulative mass loss (milligrams) was recorded, and wear rate calculated (milligrams per megacycle [Mc]). Under pristine wear conditions, particle analysis was performed, and functional biologic activity (FBA) was calculated to estimate particle debris osteolytic potential. In addition, 95% confidence intervals for all testing conditions were calculated. RESULTS: The average pristine wear rate was statistically significantly lower for the VEXPE glenoid compared with the HXLPE glenoid (0.81 ± 0.64 mg/Mc vs. 7.00 ± 0.45 mg/Mc) (P < .05). Under abrasive wear conditions, the VEXPE glenoid had a statistically significant lower average wear rate compared with the UHMWPE glenoid comparator device (18.93 ± 5.80 mg/Mc vs. 40.47 ± 2.63 mg/Mc) (P < .05). The VEXPE glenoid demonstrated a statistically significant improvement in FBA compared with the HXLPE glenoid (0.21 ± 0.21 vs. 1.54 ± 0.49 (P < .05). CONCLUSIONS: A new anatomic glenoid component with VEXPE demonstrated significantly improved pristine and abrasive wear properties with lower osteolytic particle debris potential compared with a conventional UHMWPE glenoid component. Vitamin E-enhanced polyethylene shows early promise in shoulder arthroplasty components. Long-term clinical and radiographic investigation needs to be performed to verify if these biomechanical wear properties translate to diminished long-term wear, osteolysis, and loosening.

The effect of the simulated aging by thermocycling on the elastic modulus of ethylene-vinyl acetate brands and stress/strain development during an impact: An in vitro and 3D-FEA analysis.

BACKGROUND/AIM: Mouthguards are used to prevent dental trauma and orofacial injuries. The aim of this study was to evaluate the influence of ethylene-vinyl acetate (EVA) aging by thermocycling on elastic modulus, stress, strain and shock absorption ability of different ethylene-vinyl acetate brands used for mouthguards. METHODS: Thirty EVA samples with a dimension of 70 × 10 × 3 mm were obtained from four commercial brands (Bioart®, Erkodent®, Polyshok® and Proform®). Fifteen samples were submitted to 10,000 cycles (5°C-55°C) in a thermocycling machine with an immersion time of 30 s and a transfer time of 5 s. The samples were submitted to a uniaxial tensile test in a universal testing machine to calculate the elastic modulus. Data were statistically evaluated by two-way ANOVA and Holm-Sidak test. A three-dimensional model of the anterior maxilla was created using Rhinoceros 5.0. A 3 mm custom-fitted mouthguard was simulated. The three-dimensional volumetric mesh was generated using the Patran software (MSC Software) with isoparametrics, 4-noded tetrahedral elements and exported to Marc/Mentat (MSC Software) as element number 134. A non-linear dynamic impact analysis was performed in which a rigid object struck the central incisor at a speed of 5 m/s. The stresses were evaluated by the modified von Mises criteria and the strains were also recorded. RESULTS: Statistically significant differences were observed for elastic modulus values (p < .001). Mean and standard deviation values (MPa) without thermocycling were: Bioart (34.5 ± 0.9), Erkodent (15.0 ± 0.4), Polyshok (17.3 ± 0.4), Proform: (20.6 ± 0.8); and with thermocycling: Bioart (25.4 ± 0.8), Erkodent (10.7 ± 0.5), Polyshok (13.3 ± 0.6), Proform (13.1 ± 0.6). The thermocycling process reduced stress and strain levels regardless of the mouthguard materials. Shock absorption ability calculated based on the strain values was increased with thermocycling process. CONCLUSION: The thermocycling process, regardless of the commercial brand, reduced the stress/strain and increased the shock absorption ability of mouthguards.

Comparative evaluation of marginal adaptation and fatigue resistance of endodontically treated premolars restored with direct and indirect coronal restorations: an in vitro study.

BACKGROUND: An optimum restoration for reconstructing endodontically treated teeth should provide excellent marginal adaptation, high fracture resistance as well as maximum tooth structure conservation. The purpose of this study was to evaluate the marginal adaptation and fatigue resistance of different coronal restorations in endodontically treated premolars. METHODS: Thirty sound maxillary first premolars were endodontically treated and received MOD cavities. Teeth were randomly allocated into three groups (n = 10) according to the type of coronal restoration: Group R: polyethylene fibers (ribbond), fibers-reinforced composite (everX posterior) and final layer of nano-hybrid composite. Group O: indirect lithium disilicate overlay and Group C: fiber-post, resin composite restoration, and lithium disilicate crown. Marginal gap assessment was performed before and after thermocycling (5000 cycles) using stereomicroscope. Samples were subjected to stepwise-stress loading starting at 200 N, and increased by 100 N in each step until failure occurred. Statistical analysis was done by One-way ANOVA followed Tukey`s Post Hoc test for multiple comparison. Paired t test was used to compare the marginal adaptation before and after thermocycling. Survival probability was evaluated by Life table survival analysis. Failure mode analysis was performed with Chi-square test. RESULTS: Marginal gap was significantly the lowest in group R (37.49 ± 5.05) and (42.68 ± 2.38), while being the highest in group C (59.78 ± 5.67) and (71.52 ± 5.18) in before and after thermocycling respectively (P < 0.0001). Fatigue resistance was the highest for group O (1310.8 ± 196.7), and the lowest for group R (905.4 ± 170.51) with a significant difference between groups (P < 0.0001). Crown group had the highest percentage (80%) of catastrophic failure, while, overlay group exhibited the lowest (20%). CONCLUSIONS: Direct restoration without cuspal coverage using ribbon fibers with short FRC provided better marginal adaptation than indirect overlays and crowns, but fatigue resistance wasn't significantly improved. Adhesive ceramic overlays showed the best fatigue performance and the least catastrophic failure rate compared to both direct fiber-reinforced composite and indirect ceramic full coverage restorations. CLINICAL SIGNIFICANCE: Indirect adhesive overlays are a suitable, more conservative restorative option for endodontically treated teeth than full coverage restorations, especially when tooth structure is severely compromised.

Advances in the Synthesis of Copolymers from Carbon Dioxide, Dienes, and Olefins.

Carbon dioxide (CO2) has long been considered a sustainable comonomer for polymer synthesis due to its abundance, easy availability, and low toxicity. Polymer synthesis from CO2 is highly attractive and has received continuous interest from synthetic chemists. In this regard, alternating copolymerization of CO2 and epoxides is one of the most well-established methods to synthesize aliphatic polycarbonates. Moreover, binucleophiles including diols, diamines, amino alcohols, and diynes have been reported to copolymerize with CO2 to give polycarbonates, polyureas, polyurethanes, and polyesters, respectively. Nevertheless, little success has been made for incorporating CO2 into the most widely used polyolefin materials.Although extensive studies have been focused on the copolymerization of olefins and CO2, most of the attempted reactions resulted in olefin homopolymerization owing to the endothermic property and high energy barriers of CO2 insertion during the chain propagation process. In this Account, we show how this challenge is addressed by taking advantage of a metastable lactone intermediate, 3-ethylidene-6-vinyltetrahydro-2H-pyran-2-one (EVP), which is produced from CO2 and butadiene via palladium catalysis. Homopolymerization of EVP furnishes CO2/butadiene copolymers with up to 29 wt % of CO2 content. This reaction strategy represents a breakthrough for the long-standing challenge of inherent kinetic and thermodynamically unfavorable CO2/olefin copolymerization. A new class of polymeric materials bearing repeating bicyclic lactone and unsaturated lactone units can be obtained. Importantly, one-pot copolymerization of CO2/butadiene or terpolymerization of CO2/butadiene/diene can be achieved to afford copolymers through a two-step reaction protocol. Interestingly, the bicyclic lactone units in the polymer chain can undergo ring-opening through hydrolysis and aminolysis, while reversible ring-closing of the hydrolyzed or aminolyzed units was also achieved simply by heating.Over the past few years, more and more studies have utilized EVP as an intermediate to synthesize copolymers from olefins, butadiene, and CO2. Recently, we successfully incorporated CO2 into the most widely used polyethylene materials via the direct copolymerization of EVP and ethylene. Taking advantage of the bifunctional reactivity of EVP, we were able to access two types of main-chain-functionalized polyethylenes through palladium-catalyzed coordination/insertion copolymerization and radical copolymerization. Besides polyethylenes, CO2 was also incorporated into poly(methyl methacrylate), poly(methyl acrylate), polystyrene, polymethyl acrylate, polyvinylchloroacetate, and poly(vinyl acetate) materials via radical copolymerization of EVP and olefin monomers. The EVP/olefin copolymerization strategy provides a novel avenue for the synthesis of highly versatile copolymers from an olefin, CO2, and butadiene.

Thermoregulation and golden hour practices in extremely preterm infants: an international survey.

BACKGROUND: Are thermoregulation and golden hour practices in extremely preterm (EP) infants comparable across the world? This study aims to describe these practices for EP infants based on the neonatal intensive care unit's (NICUs) geographic region, country's income status and the lowest gestational age (GA) of infants resuscitated. METHODS: The Director of each NICU was requested to complete the e-questionnaire between February 2019 and August 2021. RESULTS: We received 848 responses, from all geographic regions and resource settings. Variations in most thermoregulation and golden hour practices were observed. Using a polyethylene plastic wrap, commencing humidity within 60 min of admission, and having local protocols were the most consistent practices (>75%). The odds for the following practices differed in NICUs resuscitating infants from 22 to 23 weeks GA compared to those resuscitating from 24 to 25 weeks: respiratory support during resuscitation and transport, use of polyethylene plastic wrap and servo-control mode, commencing ambient humidity >80% and presence of local protocols. CONCLUSION: Evidence-based practices on thermoregulation and golden hour stabilisation differed based on the unit's region, country's income status and the lowest GA of infants resuscitated. Future efforts should address reducing variation in practice and aligning practices with international guidelines. IMPACT: A wide variation in thermoregulation and golden hour practices exists depending on the income status, geographic region and lowest gestation age of infants resuscitated. Using a polyethylene plastic wrap, commencing humidity within 60 min of admission and having local protocols were the most consistent practices. This study provides a comprehensive description of thermoregulation and golden hour practices to allow a global comparison in the delivery of best evidence-based practice. The findings of this survey highlight a need for reducing variation in practice and aligning practices with international guidelines for a comparable health care delivery.

Chironomus riparius Larval Gut Bacteriobiota and Its Potential in Microplastic Degradation.

Chironomus riparius are sediment-dwelling invertebrates in freshwater ecosystems and are used as indicators of environmental pollution. Their habitat is threatened by high levels of contaminants such as microplastics and organic matter. A promising strategy for the eco-friendly degradation of pollutants is the use of bacteria and their enzymatic activity. The aim of this study was to characterize for the first time bacteriobiota associated with the gut of C. riparius larvae from nature and laboratory samples, to compare it with sediment and food as potential sources of gut microbiota, and to assess its ability to degrade cellulose, proteins, and three different types of microplastics (polyethylene, polyvinyl chloride, and polyamide). The metabarcoding approach highlighted Proteobacteria, Firmicutes, Bacteroidota, and Actinobacteriota as most abundant in both gut samples. Culturable microbiota analysis revealed Metabacillus idriensis, Peribacillus simplex, Neobacillus cucumis, Bacillus thuringiensis/toyonensis, and Fictibacillus phosphorivorans as five common species for nature and laboratory samples. Two P. simplex and one P. frigoritolerans isolates showed the ability for intensive growth on polyethylene, polyvinyl chloride, and polyamide. Both cellulolytic and proteolytic activity was observed for Paenibacillus xylanexedens and P. amylolyticus isolates. The characterized strains are promising candidates for the development of environmentally friendly strategies to degrade organic pollution and microplastics in freshwater ecosystems.

Preparation of Well-Defined Fluorescent Nanoplastic Particles by Confined Impinging Jet Mixing.

Research on the origin, distribution, detection, identification, and quantification of polymer nanoparticles (NPs) in the environment and their possible impact on animal and human health is surging. For different types of studies in this field, well-defined reference materials or mimics are needed. While isolated reports on the preparation of such materials are available, a simple and broadly applicable method that allows for the production of different NP types with well-defined, tailorable characteristics is still missing. Here, we demonstrate that a confined impinging jet mixing process can be used to prepare colloidally stable NPs based on polystyrene, polyethylene, polypropylene, and poly(ethylene terephthalate) with diameters below < 100 nm. Different fluorophores were incorporated into the NPs, to allow their detection in complex environments. To demonstrate their utility and detectability, fluorescent NPs were exposed to J774A.1 macrophages and visualized using laser scanning microscopy. Furthermore, we modified the NPs in a postfabrication process and changed their shape from spherical to heterogeneous geometries, in order to mimic environmentally relevant morphologies. The methodology used here should be readily applicable to other polymers and payloads and thus a broad range of NPs that enable studies of their behavior, uptake, translocation, and biological end points in different systems.

Emissions of Formamide and Ammonia from Foam Mats: Online Measurement Based on Dopant-Assisted Photoionization TOFMS and Assessment of Their Exposure for Children.

Formamide has been classified as a Class 1B reproductive toxicant to children by the European Union (EU) Chemicals Agency. Foam mats are a potential source of formamide and ammonia. Online dopant-assisted atmospheric pressure photoionization time-of-flight mass spectrometry (DA-APPI-TOFMS) coupled with a Teflon environmental chamber was developed to assess the exposure risk of formamide and ammonia from foam mats to children. High levels of formamide (average 3363.72 mg/m3) and ammonia (average 1586.78 mg/m3) emissions were measured from 21 foam mats with three different raw material types: ethylene-vinyl acetate (EVA: n = 7), polyethylene (PE: n = 7), and cross-linked polyethylene (XPE: n = 7). The 28 day emission testing for the selected PE mat showed that the emissions of formamide were 2 orders of magnitude higher than the EU emission limit of 20 µg/m3, and formamide may be a permanent indoor contaminant for foam mat products during their life cycle. The exposure assessment of children aged 0.5-6 years showed that the exposure dose was approximately hundreds of mg/kg-day, and the age group of 0.5-2 years was subject to much higher dermal exposures than others. Thus, this study provided key relevant information for further studies on assessing children's exposure to indoor air pollution from foam mats.

Comparison of permeabilities of eight different types of cytotoxic drugs to five gloves with different materials by LC-MS/MS methods to reduce occupational exposure of medical personnel.

PURPOSE: Occupational exposure is a long-standing public health concern, which has drawn more and more attention in recent years to the problem of how to carry out occupational protection effectively. Gloves are regarded as the most critical protective equipment for cytotoxic medications. However, there is still little research conducted on the protective performance of gloves made of different materials and the optimal glove combination for cytotoxic agents. METHODS: In this research, a specific instrument intended for glove permeation experiment was designed, with various methods of liquid chromatography-tandem mass spectrometry (LC-MS/MS) developed and validated. By using the specific instrument and LC-MS/MS methods, a study was conducted on the permeation ability of eight selected cytotoxic drugs (fluorouracil, epirubicin (EPI), docetaxel (DCT), methotrexate (MTX), cyclophosphamide (CTX), etoposide (ETP), vincristine sulfate (VCR), and cisplatin derivatives Pt-(DDTC)3) into five kinds of gloves (rubber (RB), nitrile (NT), chlorinated polyethylene (CPE), low-density polyethylene, and polyvinylchloride (PVC) resin) given different contact times. Then, the experimental data were analyzed through a generalized estimation equation and Pearson correlation analysis. RESULTS: The results show that within a short period of time (less than five minutes), ETP, CTX, fluorouracil, DCT, and cisplatin passed through five types of gloves but the level of MTX, VCR, and EPI permeation was minimal, despite the duration of contact between the three drugs and the gloves reaching as long as three hours. Furthermore, the permeation of DCT and ETP was found to be positively correlated with time. CONCLUSIONS: Chlorinated polyethylene and PVC resin perform well in protecting against most cytotoxic drugs and are recommendable for clinical practice. Due to the poor protective ability, RB gloves are not recommended for this purpose. Based on the performance of various gloves in offering protection, the protection grade of two gloves can be deduced. Chlorinated polyethylene + PVC resin, CPE + NT glove combination shows good protective performance against most target drugs and can be recommended for clinical practice.

Cytotoxicity, biocompatibility and osteoinductive profile of an MTA-hydrogel-based cement: An in vitro and animal study.

AIM: This study aimed to evaluate the cytotoxicity, biocompatibility and osteoinductive profile of a mineral trioxide aggregate (MTA)-hydrogel-based material (MTA Flow) in comparison with MTA Angelus. METHODOLOGY: Cell viability was evaluated in human periodontal ligament stem cells (hPDLSCs) using the methyl-thiazol-tetrazolium (MTT) colourimetric assay. Polyethylene tubes containing the tested materials and empty polyethylene tubes (control) were implanted in the subcutaneous tissue of Wistar rats. Cellular (lymphocyte infiltration) and extracellular events (ECM; collagen fibres) were analysed in histological sections. Immunohistochemical (collagen I, osteopontin, bone sialoprotein, bone morphogenetic protein4) analyses were also performed. RESULTS: At 24, 48 and 72 h, all tested groups showed cell viability similar to control (p > .05). Regarding biocompatibility, all groups showed similar cellular events represented by a slight inflammatory reaction characterized by hyperaemia and a mild lymphocytic inflammatory infiltrate. The analysis of lymphocytes during the time showed a decrease in these cells in the control group and a significant interaction between MTA Angelus and control (p < .001), with MTA Angelus showing a more extensive inflammatory infiltrate. Regarding fibres, an increase in content was observed in all groups during the experimental time (7, 30 and 60 days), however, no difference was detected among the experimental groups (p = .063). After 60 days, the immunoexpression of bone matrix proteins in the MTA Flow group was similar to or higher than that observed in the MTA Angelus and in the control group. CONCLUSIONS: MTA Flow showed a non-cytotoxic behaviour, biocompatibility and ability to stimulate tissue mineralization.