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1.
Chirurgia (Bucur) ; 119(2): 211-217, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38743834

RESUMEN

Introduction: Pelvic organ prolapse is the most frequent and common health problem faced by most patients, representing the descent into the vagina or beyond the introitus of one or more pelvic organs, involving three compartments: anterior-bladder, apical-uterus and posterior-rectus. Lateral hystero/colpopexy is an alternative approach in the repair of symptomatic anterior and apical pelvic prolapse. The main objective is to correct pelvic floor defects, restore anatomy, relieve pressure and maintain normal sexual function. Material and Methods: Surgical intervention was applied to patients with prolapse greater than grade II according to the international prolapse quantification system (POP-Q). For apical, anterior prolapse, the bladder peritoneum is dissected and a polypropylene mesh is fitted to the round ligaments with suspension of the isthmus and cervix and fixation of the mesh with CapSure tacks followed by closure of the vaginal peritoneum. Results: During the performance of the technique I had no intraoperative or postoperative complications. Conservation of the uterus proved to be effective for prolapse correction, significant improvements in patient quality of life, frequency of nocturia, degree of dyspareunia and urgency symptoms were observed. Conclusion: Uterine preservation by lateral hystero/colpopexy is a new, feasible and successful method for treating prolapse.


Asunto(s)
Procedimientos Quirúrgicos Ginecológicos , Laparoscopía , Prolapso de Órgano Pélvico , Calidad de Vida , Mallas Quirúrgicas , Humanos , Femenino , Prolapso de Órgano Pélvico/cirugía , Laparoscopía/métodos , Resultado del Tratamiento , Procedimientos Quirúrgicos Ginecológicos/métodos , Persona de Mediana Edad , Anciano , Polipropilenos
2.
Int J Mol Sci ; 25(9)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38731902

RESUMEN

Investigation of chiroptical polymers in the solution phase is paramount for designing supramolecular architectures for photonic or biomedical devices. This work is devoted to the case study of poly(propylene oxide) (PPO) optical activity in several solvents: benzonitrile, carbon disulfide, chloroform, ethyl acetate, and p-dioxane. To attain information on the interactions in these systems, rheological testing was undertaken, showing distinct variations of the rheological parameters as a function of the solvent type. These aspects are also reflected in the refractive index dispersive behavior, from which linear and non-linear optical properties are extracted. To determine the circular birefringence and specific rotation of the PPO solutions, the alternative method of the channeled spectra was employed. The spectral data were correlated with the molecular modeling of the PPO structural unit in the selected solvents. Density functional theory (DFT) computational data indicated that the torsional potential energy-related to the O1-C2-C3-O4 dihedral angle from the polymer repeating unit-was hindered in solvation environments characterized by high polarity and the ability to interact via hydrogen bonding. This was in agreement with the optical characterization of the samples, which indicated a lower circular birefringence and specific rotation for the solutions of PPO in ethyl acetate and p-dioxane. Also, the shape of optical rotatory dispersion curves was slightly modified for PPO in these solvents compared with the other ones.


Asunto(s)
Solventes , Solventes/química , Glicoles de Propileno/química , Polipropilenos/química , Polímeros/química , Modelos Moleculares , Rotación , Enlace de Hidrógeno , Reología
3.
Int J Mol Sci ; 25(9)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38731949

RESUMEN

To enrich the properties of polylactic acid (PLA)-based composite films and improve the base degradability, in this study, a certain amount of poly(propylene carbonate) (PPC) was added to PLA-based composite films, and PLA/PPC-based composite films were prepared by melt blending and hot-press molding. The effects of the introduction of PPC on the composite films were analyzed through in-depth studies on mechanical properties, water vapor and oxygen transmission rates, thermal analysis, compost degradability, and bacterial inhibition properties of the composite films. When the introduction ratio coefficient of PPC was 30%, the tensile strength of the composite film increased by 19.68%, the water vapor transmission coefficient decreased by 14.43%, and the oxygen transmission coefficient decreased by 18.31% compared to that of the composite film without PPC, the cold crystallization temperature of the composite film increased gradually from 96.9 °C to 104.8 °C, and PPC improved the crystallization ability of composite film. The degradation rate of the composite film with PPC increased significantly compared to the previous one, and the degradation rate increased with the increase in the PPC content. The degradation rate was 49.85% and 46.22% faster on average than that of the composite film without PPC when the degradation was carried out over 40 and 80 days; the composite film had certain inhibition, and the maximum diameter of the inhibition circle was 2.42 cm. This study provides a strategy for the development of PLA-based biodegradable laminates, which can promote the application of PLA-based laminates in food packaging.


Asunto(s)
Poliésteres , Propano/análogos & derivados , Resistencia a la Tracción , Poliésteres/química , Polipropilenos/química , Embalaje de Alimentos/métodos , Vapor , Polímeros/química , Antibacterianos/química , Antibacterianos/farmacología , Temperatura
4.
Biofabrication ; 16(3)2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38574552

RESUMEN

The advent of 3D bioprinting technologies in tissue engineering has unlocked the potential to fabricatein vitrotissue models, overcoming the constraints associated with the shape limitations of preformed scaffolds. However, achieving an accurate mimicry of complex tissue microenvironments, encompassing cellular and biochemical components, and orchestrating their supramolecular assembly to form hierarchical structures while maintaining control over tissue formation, is crucial for gaining deeper insights into tissue repair and regeneration. Building upon our expertise in developing competent three-dimensional tissue equivalents (e.g. skin, gut, cervix), we established a two-step bottom-up approach involving the dynamic assembly of microtissue precursors (µTPs) to generate macroscopic functional tissue composed of cell-secreted extracellular matrix (ECM). To enhance precision and scalability, we integrated extrusion-based bioprinting technology into our established paradigm to automate, control and guide the coherent assembly ofµTPs into predefined shapes. Compared to cell-aggregated bioink, ourµTPs represent a functional unit where cells are embedded in their specific ECM.µTPs were derived from human dermal fibroblasts dynamically seeded onto gelatin-based microbeads. After 9 days,µTPs were suspended (50% v/v) in Pluronic-F127 (30% w/v) (µTP:P30), and the obtained formulation was loaded as bioink into the syringe of the Dr.INVIVO-4D6 extrusion based bioprinter.µTP:P30 bioink showed shear-thinning behavior and temperature-dependent viscosity (gel atT> 30 °C), ensuringµTPs homogenous dispersion within the gel and optimal printability. The bioprinting involved extruding several geometries (line, circle, and square) into Pluronic-F127 (40% w/v) (P40) support bath, leveraging its shear-recovery property. P40 effectively held the bioink throughout and after the bioprinting procedure, untilµTPs fused into a continuous connective tissue.µTPs fusion dynamics was studied over 8 days of culture, while the resulting endogenous construct underwent 28 days culture. Histological, immunofluorescence analysis, and second harmonic generation reconstruction revealed an increase in endogenous collagen and fibronectin production within the bioprinted construct, closely resembling the composition of the native connective tissues.


Asunto(s)
Bioimpresión , Polietilenos , Polipropilenos , Andamios del Tejido , Humanos , Andamios del Tejido/química , Bioimpresión/métodos , Poloxámero , Uridina Trifosfato , Ingeniería de Tejidos/métodos , Impresión Tridimensional
5.
J Hazard Mater ; 470: 134249, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38603909

RESUMEN

In cold regions, microplastics (MPs) in the soil undergo freeze-thaw (FT) aging process. Little is known about how FT aged MPs influence soil physico-chemical properties and microbial communities. Here, two environmentally relevant concentrations (50 and 500 mg/kg) of 50 and 500 µm polyethylene (PE) and polypropylene (PP) MPs treated soils were subjected to 45-day FT cycles (FTCs). Results showed that MPs experienced surface morphology, hydrophobicity and crystallinity alterations after FTCs. After 45-day FTCs, the soil urease (SUE) activity in control (MPs-free group that underwent FTCs) was 33.49 U/g. SUE activity in 50 µm PE group was reduced by 19.66 %, while increased by 21.16 % and 37.73 % in 500 µm PE and PP groups compared to control. The highest Shannon index was found in 50 µm PP-MPs group at 50 mg/kg, 2.26 % higher than control (7.09). Compared to control (average weighted degree=8.024), all aged MPs increased the complexity of network (0.19-1.43 %). Bacterial biomarkers of aged PP-MPs were associated with pollutant degradation. Aged PP-MPs affected genetic information, cellular processes, and disrupted the biosynthesis of metabolites. This study provides new insights into the potential hazards of MPs after FTCs on soil ecosystem in cold regions.


Asunto(s)
Microplásticos , Polietileno , Polipropilenos , Microbiología del Suelo , Contaminantes del Suelo , Ureasa , Polietileno/toxicidad , Microplásticos/toxicidad , Contaminantes del Suelo/toxicidad , Ureasa/metabolismo , Congelación , Microbiota/efectos de los fármacos , Bacterias/efectos de los fármacos , Bacterias/genética , Suelo/química
6.
J Hazard Mater ; 470: 134209, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38581880

RESUMEN

Weathered microplastics (MPs) exhibit different physicochemical properties compared to pristine MPs, thus, their effects on the environment and living organisms may also differ. In the present study, we investigated the gut-toxic effects of virgin polypropylene MPs (PP) and UV-weathered PP MPs (UV-PP) on zebrafish. The zebrafish were exposed to the two types of PP MPs at a concentration of 50 mg/L each for 14 days. After exposure, MPs accumulated primarily within the gastrointestinal tract, with UV-PP exhibiting a higher accumulation than PP. The ingestion of PP and UV-PP induced gut damage in zebrafish and increased the gene expression and levels of enzymes related to oxidative stress and inflammation, with no significant differences between the two MPs. Analysis of the microbial community confirmed alterations in the abundance and diversity of zebrafish gut microorganisms in the PP and UV-PP groups, with more pronounced changes in the PP-exposed group. Moreover, the Kyoto Encyclopedia of Genes and Genomes pathway analysis confirmed the association between changes in the gut microorganisms at the phylum and genus levels with cellular responses, such as oxidative stress, inflammation, and tissue damage. This study provides valuable insights regarding the environmental impact of MPs on organisms.


Asunto(s)
Microbioma Gastrointestinal , Microplásticos , Polipropilenos , Rayos Ultravioleta , Contaminantes Químicos del Agua , Pez Cebra , Animales , Microplásticos/toxicidad , Polipropilenos/toxicidad , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/efectos de la radiación , Contaminantes Químicos del Agua/toxicidad , Estrés Oxidativo/efectos de los fármacos , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/efectos de la radiación
7.
Chemosphere ; 357: 142056, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38641294

RESUMEN

Polypropylene (PP) and polystyrene (PS) underwent a comprehensive investigation into their mechanical and chemical degradation through reactive molecular dynamics simulations. The simulations utilized the ReaxFF force field for CHO (carbon-hydrogen-oxygen) systems in the combustion branch. The study included equilibrium simulations to determine densities and melting temperatures, non-equilibrium simulations for stress-strain and Young moduli determination, mechanical cleaving to identify surface species resulting from material fragmentation, and shock compression simulations to elucidate chemical reactions activated by some external energy sources. The results indicate that material properties such as densities, phase transition temperatures, and Young moduli are accurately reproduced by the ReaxFF-CHO force field. The reactive dynamics analysis yielded crucial insights into the surface composition of fragmented polymers. Both polymers exhibited backbone breakage, leaving -CH2· and -CH·- radicals as terminals. PP demonstrated substantial fragmentation, while PS showed a tendency to develop crosslinks. A detailed analysis of chemical reactions resulting from increasing activation due to increasing value of compression pressure is presented and discussed.


Asunto(s)
Polipropilenos , Poliestirenos , Poliestirenos/química , Polipropilenos/química , Simulación de Dinámica Molecular , Presión , Modelos Químicos
8.
Mikrochim Acta ; 191(5): 265, 2024 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-38625451

RESUMEN

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.


Asunto(s)
Encéfalo , Ácidos Cafeicos , Polietilenos , Polipropilenos , Privación de Sueño , Animales , Ratones , Aparato de Golgi , Suplementos Dietéticos
9.
Artículo en Inglés | MEDLINE | ID: mdl-38583695

RESUMEN

Human activities have directly impacted the environment, causing significant ecological imbalances. From the different contaminants resulting from human activities, plastics are of major environmental concern. Due to their high use and consequent discharge, plastics tend to accumulate in aquatic environments. There, plastics can form smaller particles (microplastics, MPs), due to fragmentation and weathering, which are more prone to interact with aquatic organisms and cause deleterious effects, including at the basis of different food webs. This study assessed the effects of two microplastics (polyethylene terephthalate, PET; and polypropylene, PP; both of common domestic use) in the freshwater cladoceran species Daphnia magna. Toxic effects were assessed by measuring reproductive traits (first brood and total number of offspring), and activities of biomarkers involved in xenobiotic metabolism (phase I: cytochrome P-450 isoenzymes CYP1A1, 1A2 and 3A4; phase II/conjugation: glutathione S-transferases; and antioxidant defense (catalase)). Both MPs showed a potential to significantly reduce reproductive parameters in D. magna. Furthermore, PET caused a significant increase in some isoenzymes of CYP450 in acutely exposed organisms, but this effect was not observed in chronically exposed animals. Similarly, the activity of the antioxidant defense (CAT) was significantly increased in acutely exposed animals, but not in chronically exposed organisms. This pattern of effects suggests a possible mechanism of long-term adaptation to the presence of the tested MPs. In conclusion, the herein tested MPs have shown the potential to induce deleterious effects on D. magna mainly observed in terms of the reproductive outcomes. Changes at the biochemical level seems transient and are not likely to occur in long term, environmentally exposed crustaceans.


Asunto(s)
Daphnia , Microplásticos , Reproducción , Contaminantes Químicos del Agua , Animales , Daphnia/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Reproducción/efectos de los fármacos , Microplásticos/toxicidad , Agua Dulce , Biomarcadores/metabolismo , Glutatión Transferasa/metabolismo , Polipropilenos/toxicidad , Sistema Enzimático del Citocromo P-450/metabolismo , Daphnia magna
10.
Biomater Sci ; 12(10): 2730-2742, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38639196

RESUMEN

Polypropylene (PP) mesh is widely used in hernioplasty, but it is prone to contamination by pathogenic bacteria. Here, we present an infection microenvironment-responsive metal-phenolic network (MPN) coating, which is made up of Cu2+ and tannic acid (TA) (referred to as CT coating), and is fabricated on PP meshes by layer-by-layer (LbL) assembly. The CT coating provided a robust protection for the PP mesh from pathogenic bacterial infection in a pH-responsive manner due to the pH-responsive disassembly kinetics of MPN complexes. Moreover, the PP meshes with ten CT coating cycles (PP-CT(10)) exhibited excellent stability in a physiological environment, with the killing ratio against "superbug" methicillin-resistant Staphylococcus aureus (MRSA) at pH 5.5 exceeding 99% even after 28 days of PBS (pH 7.4) immersion. In addition, the PP-CT(10) exhibited excellent in vivo anti-infective ability in a rodent subcutaneous implant MRSA infection model, and the results of histological and immunohistochemical analyses demonstrated that the reduced bacterial number alleviated the inflammatory response at implant sites. This study revealed that MPN coating is a promising strategy, which could provide a self-defensive ability for various implants to combat post-surgical infections in a pH-responsive manner.


Asunto(s)
Antibacterianos , Staphylococcus aureus Resistente a Meticilina , Polipropilenos , Mallas Quirúrgicas , Taninos , Concentración de Iones de Hidrógeno , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Animales , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/administración & dosificación , Polipropilenos/química , Taninos/química , Taninos/farmacología , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Infecciones Estafilocócicas/tratamiento farmacológico , Herniorrafia , Cobre/química , Cobre/farmacología , Ratones
11.
J Hazard Mater ; 471: 134343, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38640671

RESUMEN

Microplastics are a growing concern in mangrove ecosystems; however, their effects on archaeal communities and related ecological processes remain unclear. We conducted in situ biofilm-enrichment experiments to investigate the ecological influence of polyethylene (PE) and polypropylene microplastics on archaeal communities in the sediments of mangrove ecosystems. The archaeal community present on microplastics was distinct from that of the surrounding sediments at an early stage but became increasingly similar over time. Bathyarchaeota, Thaumarchaeota, Euryarchaeota, and Asgardaeota were the most abundant phyla. Methanolobus, an archaeal biomarker, was enriched in PE biofilms, and significantly controlled by homogeneous selection in the plastisphere, indicating an increased potential risk of methane emission. The dominant archaeal assembly process in the sediments was deterministic (58.85%-70.47%), while that of the PE biofilm changed from stochastic to deterministic during the experiment. The network of PE plastispheres showed less complexity and competitive links, and higher modularity and stability than that of sediments. Functional prediction showed an increase in aerobic ammonia oxidation during the experiment, whereas methanogenesis and chemoheterotrophy were significantly higher in the plastisphere. This study provides novel insights into the impact of microplastic pollution on archaeal communities and their mediating ecological functions in mangrove ecosystems.


Asunto(s)
Archaea , Biopelículas , Sedimentos Geológicos , Microplásticos , Polietileno , Polipropilenos , Humedales , Archaea/efectos de los fármacos , Archaea/metabolismo , Sedimentos Geológicos/microbiología , Sedimentos Geológicos/química , Microplásticos/toxicidad , Biopelículas/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Ecosistema
12.
J Hazard Mater ; 471: 134328, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38643575

RESUMEN

The microbial degradation of polyethylene (PE) and polypropylene (PP) resins in rivers and lakes has emerged as a crucial issue in the management of microplastics. This study revealed that as the flow rate decreased longitudinally, ammonia nitrogen (NH4+-N), heavy fraction of organic carbon (HFOC), and small-size microplastics (< 1 mm) gradually accumulated in the deep and downstream estuarine sediments. Based on their surface morphology and carbonyl index, these sediments were identified as the potential hot zone for PE/PP degradation. Within the identified hot zone, concentrations of PE/PP-degrading genes, enzymes, and bacteria were significantly elevated compared to other zones, exhibiting strong intercorrelations. Analysis of niche differences revealed that the accumulation of NH4+-N and HFOC in the hot zone facilitated the synergistic coexistence of key bacteria responsible for PE/PP degradation within biofilms. The findings of this study offer a novel insight and comprehensive understanding of the distribution characteristics and synergistic degradation potential of PE/PP in natural freshwater environments.


Asunto(s)
Bacterias , Biodegradación Ambiental , Sedimentos Geológicos , Polietileno , Polipropilenos , Contaminantes Químicos del Agua , Polipropilenos/química , Polietileno/química , Polietileno/metabolismo , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/química , Sedimentos Geológicos/microbiología , Sedimentos Geológicos/química , Bacterias/metabolismo , Bacterias/genética , Microplásticos/toxicidad , Microplásticos/metabolismo , Agua Dulce/microbiología , Estuarios
13.
BMJ Case Rep ; 17(4)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38688574

RESUMEN

A man in his 30s came to our clinic with a year-long history of progressive pain and swelling in his knee. Diagnostic imaging revealed a displaced patellar fracture with an osteolytic, septated lesion and thinned expanded cortex in both fracture fragments. A core needle biopsy confirmed the diagnosis of giant cell tumour. Treatment involved wide excision of the tumour and the use of polypropylene mesh and a peroneal longus tendon autograft to reconstruct the extensor mechanism of the knee joint. One year postoperatively, the patient experienced no pain, demonstrated full range of motion and showed no signs of functional impairment or local tumour recurrence. This case highlights that reconstruction of the extensor mechanism of the knee after tumour excision with synthetic mesh is an affordable, user-friendly and widely accessible method. It can address large defects effectively while minimising the risks of disease transmission and graft lengthening, resulting in satisfactory outcomes.


Asunto(s)
Neoplasias Óseas , Rótula , Polipropilenos , Mallas Quirúrgicas , Humanos , Masculino , Rótula/cirugía , Rótula/lesiones , Rótula/diagnóstico por imagen , Neoplasias Óseas/cirugía , Neoplasias Óseas/complicaciones , Adulto , Tumor Óseo de Células Gigantes/cirugía , Fracturas Espontáneas/cirugía , Fracturas Espontáneas/etiología , Fracturas Espontáneas/diagnóstico por imagen , Procedimientos de Cirugía Plástica/métodos , Resultado del Tratamiento
14.
Eur J Pharm Biopharm ; 199: 114297, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38641228

RESUMEN

Spray-drying of nucleic acid-based drugs designed for gene therapy or gene knockdown is associated with many advantages including storage stability and handling as well as the possibility of pulmonary application. The encapsulation of nucleic acids in nanoparticles prior to spray-drying is one strategy for obtaining efficient formulations. This, however, strongly relies on the definition of optimal nanoparticles, excipients and spray-drying conditions. Among polymeric nanoparticles, polyethylenimine (PEI)-based complexes with or without chemical modifications have been described previously as very efficient for gene or oligonucleotide delivery. The tyrosine-modification of linear or branched low molecular weight PEIs, or of polypropylenimine (PPI) dendrimers, has led to high complex stability, improved cell uptake and transfection efficacy as well as high biocompatibility. In this study, we identify optimal spray-drying conditions for PEI-based nanoparticles containing large plasmid DNA or small siRNAs, and further explore the spray-drying of nanoparticles containing chemically modified polymers. Poly(vinyl alcohol) (PVA), but not trehalose or lactose, is particularly well-suited as excipient, retaining or even enhancing transfection efficacies compared to fresh complexes. A big mesh size is critically important as well, while the variation of the spray-drying temperature plays a minor role. Upon spray-drying, microparticles in a âˆ¼ 3.3 - 8.5 µm size range (laser granulometry) are obtained, dependent on the polymers. Upon their release from the spray-dried material, the nanoparticles show increased sizes and markedly altered zeta potentials as compared to their fresh counterparts. This may contribute to their high efficacy that is seen also after prolonged storage of the spray-dried material. We conclude that these spray-dried systems offer a great potential for the preparation of nucleic acid drug storage forms with facile reconstitution, as well as for their direct pulmonary application as dry powder.


Asunto(s)
ADN , Nanopartículas , Polietileneimina , ARN Interferente Pequeño , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/química , Nanopartículas/química , Polietileneimina/química , ADN/administración & dosificación , ADN/química , Humanos , Técnicas de Transferencia de Gen , Secado por Pulverización , Transfección/métodos , Polipropilenos/química , Excipientes/química , Tamaño de la Partícula , Plásmidos/administración & dosificación , Desecación/métodos , Alcohol Polivinílico/química
15.
Environ Int ; 186: 108635, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38631261

RESUMEN

To overcome ethical and technical challenges impeding the study of human dermal uptake of chemical additives present in microplastics (MPs), we employed 3D human skin equivalent (3D-HSE) models to provide first insights into the dermal bioavailability of polybrominated diphenyl ether (PBDEs) present in MPs; and evaluated different factors influencing human percutaneous absorption of PBDEs under real-life exposure scenario. PBDEs were bioavailable to varying degrees (up to 8 % of the exposure dose) and percutaneous permeation was evident, albeit at low levels (≤0.1 % of the exposure dose). While the polymer type influenced the release of PBDEs from the studied MPs to the skin, the polymer type was less important in driving the percutaneous absorption of PBDEs. The absorbed fraction of PBDEs was strongly correlated (r2 = 0.88) with their water solubility, while the dermal permeation coefficient Papp of PBDEs showed strong association with their molecular weight and logKOW. More sweaty skin resulted in higher bioavailability of PBDEs from dermal contact with MPs than dry skin. Overall, percutaneous absorption of PBDEs upon skin contact with MPs was evident, highlighting, for the first time, the potential significance of the dermal pathway as an important route of human exposure to toxic additive chemicals in MPs.


Asunto(s)
Retardadores de Llama , Éteres Difenilos Halogenados , Microplásticos , Polietileno , Polipropilenos , Absorción Cutánea , Humanos , Éteres Difenilos Halogenados/farmacocinética , Piel/metabolismo , Modelos Biológicos
16.
Environ Sci Technol ; 58(15): 6647-6658, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38563431

RESUMEN

The biodegradation of polypropylene (PP), a highly persistent nonhydrolyzable polymer, by Tenebrio molitor has been confirmed using commercial PP microplastics (MPs) (Mn 26.59 and Mw 187.12 kDa). This confirmation was based on the reduction of the PP mass, change in molecular weight (MW), and a positive Δδ13C in the residual PP. A MW-dependent biodegradation mechanism was investigated using five high-purity PP MPs, classified into low (0.83 and 6.20 kDa), medium (50.40 and 108.0 kDa), and high (575.0 kDa) MW categories to access the impact of MW on the depolymerization pattern and associated gene expression of gut bacteria and the larval host. The larvae can depolymerize/biodegrade PP polymers with high MW although the consumption rate and weight losses increased, and survival rates declined with increasing PP MW. This pattern is similar to observations with polystyrene (PS) and polyethylene (PE), i.e., both Mn and Mw decreased after being fed low MW PP, while Mn and/or Mw increased after high MW PP was fed. The gut microbiota exhibited specific bacteria associations, such as Kluyvera sp. and Pediococcus sp. for high MW PP degradation, Acinetobacter sp. for medium MW PP, and Bacillus sp. alongside three other bacteria for low MW PP metabolism. In the host transcriptome, digestive enzymes and plastic degradation-related bacterial enzymes were up-regulated after feeding on PP depending on different MWs. The T. molitor host exhibited both defensive function and degradation capability during the biodegradation of plastics, with high MW PP showing a relatively negative impact on the larvae.


Asunto(s)
Microbiota , Tenebrio , Animales , Tenebrio/metabolismo , Tenebrio/microbiología , Plásticos , Polipropilenos/metabolismo , Microplásticos , Peso Molecular , Poliestirenos , Larva/metabolismo , Bacterias/metabolismo , Biodegradación Ambiental
17.
Environ Sci Technol ; 58(16): 7124-7132, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38599582

RESUMEN

Often large quantities of plastics are found in compost, with price look-up stickers being a major but little-explored component in the contamination path. Stickers glued to fruit or vegetable peels usually remain attached to the organic material despite sorting processes in the composting plant. Here, we investigated the effects of industrial composting on the structural alterations of these stickers. Commercial polypropylene (PP) stickers on banana peels were added to a typical organic material mixture for processing in an industrial composting plant and successfully resampled after a prerotting (11 days) and main rotting step (25 days). Afterward, both composted and original stickers were analyzed for surface and structural changes via scanning electron microscopy, Fourier-transform infrared spectroscopy, and micro- and nano-X-ray computed tomography (CT) combined with deep learning approaches. The composting resulted in substantial surface changes and degradation in the form of microbial colonization, deformation, and occurrence of cracks in all stickers. Their pore volumes increased from 16.7% in the original sticker to 26.3% at the end of the compost process. In a similar way, the carbonyl index of the stickers increased. Micro-CT images additionally revealed structural changes in the form of large adhesions that penetrated the surface of the sticker. These changes were accompanied by delamination after 25 days of composting, thus overall hinting at the degradation of the stickers and the subsequent formation of smaller microplastic pieces.


Asunto(s)
Compostaje , Frutas , Plásticos , Tomografía Computarizada por Rayos X , Suelo/química , Microscopía Electrónica de Rastreo , Polipropilenos/química
18.
Int Ophthalmol ; 44(1): 208, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38683414

RESUMEN

PURPOSE: To present the modified surgery technique of new suture probe canaloplasty with a specially prepared monofilament 4.0 polypropylene suture combined with suprachoroidal drainage (ScD) and collagen sheet implantation for non-penetrating glaucoma surgery. METHODS: Prospective study with a twelve months follow-up. A standard 4/0 polypropylene suture (ProleneTM by Ethicon; thickness: approximately 250 m) is cut and shaped with an ophthalmic knife (MANI® Crescent Knife, Mani Inc 8-3 Kiyohara Industrial Park, Utsunomiya, Tochigi 321-3231, Japan) to create a blunt end without sharp or compressed edges. This improves suture probe canaloplasty by providing a more stable and smoother probing device. Schlemm's canal is prepared using the standard technique of canaloplasty with suprachoroidal drainage. Then, instead of using the canaloplasty microcatheter or the previously published 6/0 double-helix suture, Schlemm's canal is probed with the blunt ending of the 4/0 Prolene suture. After successful 360-degree probing, a doubled 10/0 polypropylene tension suture is threaded through the tip of the 4/0 suture. The 4/0 suture is then pulled back and the 10/0 tension sutures are tied at both ends to tension Schlemm's canal. A special collagen sheet (Ologen®) is placed in suprachoroidal space, and the scleral flap is firmly sewed. RESULTS: 115 eyes were included in this prospective study. In 113 cases the Schlemm's canal could completely be probed with the suture probe and canaloplasty with ScD and collagen sheet implantation succeeded. In two cases the intervention was transformed to 360-degree suture trabeculotomy due to an intraoperative cheese-wiring. Twelve months after successful new suture probe canaloplasty with ScD and Collagen Implantation the IOP had decreased by 37.1% (from 21.6 ± 6.0 mmHg with 3.3 different IOP lowering eye drops to 13.5 ± 3.5 mmHg with 1.0 eye drops). 16 Patients did not achieve sufficient IOP levels and underwent 360-degree suture trabeculotomy during the follow-up. One patient had to be treated with further glaucoma surgery to achieve a sufficient IOP level. Complications were hyphema, postoperative IOP elevation and transient hypotony. No serious or sight-threatening complications occurred. CONCLUSION: New suture probe canaloplasty with ScD and collagen sheet implantation yields the opportunity to conduct a cost-effective canaloplasty easier and less complicated than with the previously described method with the twisted 6/0 suture. The safety profile and IOP lowering effect is comparable. In cases where complete probing fails, there is still the opportunity to switch to suture trabeculotomy over the majorly probed part of Schlemm's canal. The pressure lowering effect of the deep sclerectomy with ScD and suprachoroidal collagen sheet implant seems to have an additional impact on the sufficient pressure lowering procedure.


Asunto(s)
Colágeno , Presión Intraocular , Técnicas de Sutura , Suturas , Humanos , Técnicas de Sutura/instrumentación , Estudios Prospectivos , Presión Intraocular/fisiología , Masculino , Femenino , Polipropilenos , Estudios de Seguimiento , Glaucoma/cirugía , Persona de Mediana Edad , Anciano , Coroides/cirugía , Cirugía Filtrante/métodos
19.
Environ Sci Technol ; 58(17): 7609-7616, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38624261

RESUMEN

The carbonyl index aims to measure the degradation level and is used in plastic degradation research as a proxy for the general degradation level of collected plastic pieces. According to the choices for carbonyl index calculation, comparison using this index is prevented and must be unveiled by the authors, which does not always happen. In order to study the proper usage of the carbonyl index, regarding the choice of the reference band and the usage of the band intensity or the absorption area, we systematically reviewed the methodologies used for polypropylene as a case study. Based on 95 studies gathered from 2000 to 2024, two main methods were used to determine the carbonyl index: the ratio between the carbonyl band area and the reference band area (33.68%) and the ratio between the highest intensity of the carbonyl band and the reference band (66.31%). The reference band of choice and the type of calculation method produce different carbonyl index values for the same spectra and mean different information, preventing comparison among works with different calculations.


Asunto(s)
Polímeros , Plásticos , Polipropilenos/química
20.
Mol Med ; 30(1): 52, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38641575

RESUMEN

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.


Asunto(s)
Polietilenos , Polipropilenos , Enfermedades de la Piel , Factor de Crecimiento Transformador beta , Animales , Ratones , Bleomicina/efectos adversos , Colágeno/metabolismo , Fibrosis/tratamiento farmacológico , Hidrogeles/química , Hidrogeles/farmacología , Polietilenos/farmacología , Polipropilenos/farmacología , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Enfermedades de la Piel/inducido químicamente , Enfermedades de la Piel/tratamiento farmacológico , Enfermedades de la Piel/metabolismo , Proteínas Smad/efectos de los fármacos , Proteínas Smad/metabolismo , Piel/efectos de los fármacos , Piel/metabolismo , Piel/patología
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