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This study investigates the regulatory mechanisms of synovial macrophages and their polarization in the progression of temporomandibular joint osteoarthritis (TMJOA). Macrophage depletion models were established by intra-articular injection of clodronate liposomes and unloaded liposomes. TMJOA was induced by intra-articular injection of 50 µL Complete Freund's Adjuvant and the surgery of disc perforation. The contralateral joint was used as the control group. The expression of F4/80, CD86, and CD206 in the synovium was detected by immunofluorescence staining analysis. Hematoxylin and eosin staining and TMJOA synovial score were detected to show the synovial changes in rat joints after TMJOA induction and macrophage depletion. Changes in rat cartilage after TMJOA induction and macrophage depletion were shown by safranin fast green staining. The bone-related parameters of rats' joints were evaluated by micro-computed tomography analysis. The TMJOA model induced by Complete Freund's Adjuvant injection and disc perforation aggravated synovial hyperplasia and showed a significant up-regulation of expression of F4/80-, CD86-, and CD206-positive cells. F4/80, CD86, and CD206 staining levels were significantly decreased in macrophage depletion rats, whereas the synovitis score further increased and cartilage and subchondral bone destruction was slightly aggravated. Macrophages were crucially involved in the progression of TMJOA, and macrophage depletion in TMJOA synoviocytes promoted synovitis and cartilage destruction.
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Cartílago Articular , Osteoartritis , Sinovitis , Ratas , Animales , Microtomografía por Rayos X , Activación de Macrófagos , Adyuvante de Freund/efectos adversos , Adyuvante de Freund/metabolismo , Liposomas/efectos adversos , Liposomas/metabolismo , Cartílago Articular/metabolismo , Articulación Temporomandibular/metabolismo , Sinovitis/metabolismo , Remodelación Ósea , Osteoartritis/metabolismoRESUMEN
The abrasion of synthetic textile fibers is a significant factor in the generation of environmental microplastic fibers (MPFs). The extent to which polymer sponges designed specifically for surface cleaning have a tendency to release MPFs during normal use remains unknown. Here, the tribological behaviors of melamine cleaning sponges (also known as "magic erasers") with different strut densities against metal surfaces of different roughness were investigated using a reciprocating abrader. The MPFs formed by sponge wear under various conditions were characterized in terms of their morphology, composition, and quantity. They were mainly composed of poly(melamine-formaldehyde) polymer with linear or branched fiber morphologies (10-405 µm in length), which were formed through deformation and fracture of the struts within open cells of the sponges, facilitated by friction-induced polymer decomposition. The rate and capability of MPF production generally increased with increasing roughness of the metal surface and density of the struts, respectively. The sponge wear could release 6.5 million MPFs/g, which could suggest a global overall emission of 4.9 trillion MPFs due to sponge consumption. Our study reveals a hitherto unrecognized source of the environmental MPF contamination and highlights the need to evaluate exposure risks associated with these new forms of MPFs.
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Microplásticos , Polímeros/química , TextilesRESUMEN
INTRODUCTION: Orthodontically induced root resorption (OIRR) is a common and undesirable consequence of orthodontic treatment. Traditionally, studies employ manual methods to conduct 3-dimensional quantitative analysis of OIRR via cone-beam computed tomography (CBCT), which is often subjective and time-consuming. With advancements in computer technology, deep learning-based approaches have gained traction in medical image processing. This study presents a deep learning-based model for the fully automatic extraction of root volume information and the localization of root resorption from CBCT images. METHODS: In this cross-sectional, retrospective study, 4534 teeth from 105 patients were used to train and validate an automatic model for OIRR quantification. The protocol encompassed several steps: preprocessing of CBCT images involving automatic tooth segmentation and conversion into point clouds, followed by segmentation of tooth crowns and roots via the Dynamic Graph Convolutional Neural Network. The root volume was subsequently calculated, and OIRR localization was performed. The intraclass correlation coefficient was employed to validate the consistency between the automatic model and manual measurements. RESULTS: The proposed method strongly correlated with manual measurements in terms of root volume and OIRR severity assessment. The intraclass correlation coefficient values for average volume measurements at each tooth position exceeded 0.95 (P <0.001), with the accuracy of different OIRR severity classifications surpassing 0.8. CONCLUSIONS: The proposed methodology provides automatic and reliable tools for OIRR assessment, offering potential improvements in orthodontic treatment planning and monitoring.
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This study aimed to introduce the clinical application of the CAD/CAM-guided modified Dautrey's procedure in recurrent anterior temporomandibular joint luxation and evaluate its clinical effects. Four selected patients were treated by the CAD/CAM-guided modified Dautrey's procedure and were followed-up to access their curative effect. Joint pain and sound, recurrence rate, mandibular function, maximum mouth opening (MMO), symptoms of facial nerve injury, and changes in zygomatic facial appearance were observed in postoperative follow-up. The followed-up period ranged from 3 months to 1 year with an average time of 7.5 months. There was no recurrence in all 4 patients, and no symptoms of facial nerve injury and zygomaticofacial appearance changes were found. All patients showed improvement in MMO, with a mean preoperative and postoperative MMO of 4.74 and 3.74 cm, respectively. All of them showed relief of joint pain or sound 3 months or more after the operation and could exercise mandibular normally. This results showed that the CAD/CAM-guided modified Dautrey's procedure was effective in the treatment of recurrent temporomandibular joint luxation and could be used as a good alternative treatment for it.
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Traumatismos del Nervio Facial , Luxaciones Articulares , Trastornos de la Articulación Temporomandibular , Humanos , Trastornos de la Articulación Temporomandibular/cirugía , Luxaciones Articulares/cirugía , Artralgia , Articulación Temporomandibular/cirugía , Rango del Movimiento Articular/fisiología , Resultado del TratamientoRESUMEN
PURPOSE: Nano-drug delivery systems are designed to contain surface ligands including antibodies for "active targeting". The number of ligands on each nanoparticle, known as the valency, is considered a critical determinant of the "targeting" property. We sought to understand the correlation between valency and binding properties using antibody conjugated liposomes, i.e. immunoliposomes (ILs), as the model. METHODS: Anti-CD3 Fab containing a terminal cysteine residue were conjugated to DSPE-PEG-maleimide and incubated with preformed liposomes at 60°C. The un-incorporated antibodies were removed and the obtained ILs were characterized to contain in average 2-22 copies of anti-CD3 Fabs per liposome. The Biolayer Interferometry (BLI) probe surface was coated with various densities of CD3 epsilon&delta heterodimer (CD3D/E) to imitate different CD3 expression levels on target cells. The inference wavelength shifts upon anti-CD3 liposome binding were monitored and analyzed. RESULTS: The data indicated ILs may bind either monovalently or multivalently, determined mainly by the surface ligand density rather than the ILs antibody valency. The ILs valency indeed correlated with the dissociation rate constant (Koff), but not with the association rate constant (Kon). Their binding capabilities also did not necessarily increase with the surface anti-CD3 valency. CONCLUSION: We proposed a model for understanding the binding properties of ILs with different ligand valencies. The binding mode may change when the targeted surfaces had different antigen densities. The model should be important for the designing and optimization of active targeting drug delivery systems to fit different applications.
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Inmunoconjugados/química , Liposomas/química , Animales , Anticuerpos Monoclonales/química , Complejo CD3/química , Células CHO , Cricetulus , Sistemas de Liberación de Medicamentos/métodos , Ligandos , Maleimidas/química , Nanopartículas/química , Fosfatidiletanolaminas/química , Polietilenglicoles/químicaRESUMEN
BACKGROUND: Dental anxiety (DA) has an impact on the quality of dental treatment and may have long-lasting implications for children. A recent study introducing experiential learning (EL) into children's oral health promotion resulted in better oral hygiene. The purpose of the study is to evaluate whether EL can reduce children's DA. METHODS: In September 2018, we recruited 988 children aged 7-8 years from 24 classes to participate in a cluster-randomized trial. Classes were randomly assigned to EL (in which children received a lively presentation on oral health and participated in a role play in a simulated dental clinic in the classroom) or the Tell-Show-Do (TSD) group (in which children received a conventional TSD behavior management). The primary outcome was the prevalence of high DA after the procedure of pit and fissure sealant (PFS), assessed by a modified Children's Fear Survey Schedule-Dental Subscale. Secondary outcomes were changes in blood pressures (BP) and pulse rates (PR) before and after the PFS procedure. The intervention effects were estimated by means of mixed effect models, which included covariates of gender and school (and baseline value for BP and PR only), and a random cluster effect. RESULTS: In 396 children of the EL group who received the PFS treatment, the prevalence of high DA (score ≥ 38) was 18.5%, compared with 24.3% in 391 children of the TSD group (OR = 0.65; 95% confidence interval, 0.46-0.93; P = 0.019). The increases in BP and PR after the PFS were also significantly less in the EL group. CONCLUSION: School-based experiential learning intervention before a dental visit is feasible and effective in reducing children's dental anxiety during PFS. TRIAL REGISTRATION: The trial was registered in Chinese Clinical Trial Registry on 5 January 2020 (No.: ChiCTR2000028878 , retrospectively registered).
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Ansiedad al Tratamiento Odontológico , Aprendizaje Basado en Problemas , Niño , Ansiedad al Tratamiento Odontológico/prevención & control , Humanos , Salud Bucal , Higiene Bucal , Selladores de Fosas y FisurasRESUMEN
Due to the anatomic and functional complexity, reconstruction of the condylar process after mandibular tumor extirpation remains a surgical challenge. The aim of this study was to present the results and experience of condyle head reimplantation combined with vascularized free flap for mandibular reconstruction in our institution. In the current study, the authors evaluated the clinical features of condyle head reimplantation combined with vascularized free flap for mandibular reconstruction in 5 patients with benign mandibular intraosseous lesions from December 2013 to March 2015 in our institution. All patients showed nearly normal mouth opening, with minimal mandibular deviation and joint symptoms. The radiograph data showed that 4 patients had no obvious bone resorption of condyles while only 1 patient had prominent condyle resorption. All the condyles were cut above the condylar neck, with the biggest remaining condyle height being 2.8âcm and the smallest one being 1.1âcm. Moreover, the original vertical height of mandibular ramus was decreased by 2 to 3âmm during the surgery. In conclusion, this study revealed that combining the condyle reimplantation with vascularized free flap constitutes a reliable method in condylar reconstruction and a slight reduction of the vertical height of condyles may help to diminish unfavorable outcomes.
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Colgajos Tisulares Libres/cirugía , Cóndilo Mandibular/cirugía , Reconstrucción Mandibular/métodos , Humanos , Neoplasias Mandibulares/cirugíaRESUMEN
The formation of dual-layer asymmetric porous structures in surfactant-based systems is significantly influenced by emulsions. Surfactants self-assemble to alter the conformational arrangement of polysaccharides, while gravity disrupts the initial uniformity of the established equilibrium droplet concentration gradient in the emulsion, thus achieving delamination. Specifically, high-speed rotation and non-instantaneous freezing allow the gelatin solution to form two different states of foam layers. The integrated dual-layer asymmetric porous structure, composed of polysaccharides and tannic acid, is constructed with gelatin as a skeleton and surfactant. This innovative approach eliminates the need to consider the toxicity of chemically synthesized surfactants and expands the concept of gelatin utilization. This intriguing structure exhibits a variety of desirable characteristics within 30â¯days (e.g., tailorable performance, ultrarapid antioxidant activity, efficient antibacterial activity, low differential blood clotting index, and good hemocompatibility and cytocompatibility), suggesting its potential as a valuable reference for applying hierarchical porous structures, thereby offering more formulation flexibility for biomaterials with adjustable properties.
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Gelatina , Polifenoles , Polisacáridos , Tensoactivos , Taninos , Gelatina/química , Taninos/química , Polisacáridos/química , Polisacáridos/farmacología , Porosidad , Tensoactivos/química , Tensoactivos/farmacología , Tensoactivos/síntesis química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Humanos , Animales , Emulsiones/química , Coagulación Sanguínea/efectos de los fármacosRESUMEN
Biomedical materials can produce high efficiency and special behavior with an integrated internal structure. It is possible that changing the structure of biomedical materials could extend and promote the application of eco-friendly and multifunctional biomaterials. However, the instantaneous formation of complex structures between tannic acid (TA) and polysaccharides is disrupted, and the reconstruction of the new porous structure becomes a key issue. Here, we present an innovative one-step forming method for an asymmetric dual-layer porous structure of carboxymethyl chitosan (CC)/sodium alginate (SA)/TA, which can be utilized in various biomedical applications. Even after 6â¯months of storage, it still demonstrates a range of desirable properties including tailorable performance, efficient antibacterial activity, ultrarapid antioxidant activity, low differential blood clotting index and cytotoxicity. This suggests its potential for regulating and controlling wound bleeding, providing flexible possibilities for potential applications in biomedicine.
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Quitosano , Polisacáridos , Porosidad , Polisacáridos/farmacología , Polisacáridos/química , Quitosano/farmacología , Quitosano/química , Alginatos/química , Antibacterianos/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/químicaRESUMEN
Neocaridina denticulata sinensis has emerged as a promising model organism for basic studies in Decapod. However, the current transcriptome information on this species is based on next-generation sequencing technologies, which are limited by a short read length. Therefore, the present study aimed to generate a full-length transcriptome assembly of N. denticulata sinensis utilizing the PacBio Sequel â ¡ platform. The resulting transcriptome assembly comprised 5831 transcripts with an N50 value of 3697 bp. Remarkably, 90.5% of these transcripts represented novel isoforms of known genes. The transcripts were further searched against the NR, SwissProt, KEGG, KOG, GO, NT, and Pfam databases. A total of 24.8% of the transcripts can be annotated across all seven databases. Additionally, 1236 alternative splicing events, 344 transcription factors, and 124 long non-coding RNAs (LncRNAs) were predicted. Based on the alternative splicing annotation results, a RING finger protein NHL-1 gene from N. denticulata sinensis (NdNHL-1) was identified. There are 15 transcripts in NdNHL-1. The longest transcript is 4995 bp in length and encodes a putative protein of 1665 amino acids. A phylogenetic analysis showed its close relationship with NHL-1 from other crustacean species. This report represents the full-length transcriptome of N. denticulata sinensis and will facilitate research on functional genomics and environmental adaptation in this species.
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To enhance the enzymatic digestibility of polyethylene terephthalate (PET), which is highly oriented and crystallized, a polyethylene glycol (PEG) surfactant of varying molecular weights was utilized to improve the stability of mutant cutinase from Humicola insolens (HiC) and to increase the accessibility of the enzyme to the substrate. Leveraging the optimal conditions for HiC hydrolysis of PET, the introduction of 1 % w/v PEG significantly increased the yield of PET hydrolysis products. PEG600 was particularly effective, increasing the yield by 64.58 % compared to using HiC alone. Moreover, the mechanisms by which PEG600 and PEG6000 enhance enzyme digestion were extensively examined using circular dichroism and fluorescence spectroscopy. The results from CD and fluorescence analyses indicated that PEG alters the protein conformation, thereby affecting the catalytic effect of the enzyme. Moreover, PEG improved the affinity between HiC and PET by lowering the surface tension of the solution, substantially enhancing PET hydrolysis. This study suggests that PEG holds considerable promise as an enzyme protector, significantly aiding in the hydrophilic modification and degradation of PET in an environmentally friendly and sustainable manner.
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Hidrolasas de Éster Carboxílico , Polietilenglicoles , Tereftalatos Polietilenos , Tensoactivos , Tereftalatos Polietilenos/química , Polietilenglicoles/química , Hidrólisis , Tensoactivos/química , Hidrolasas de Éster Carboxílico/química , Hidrolasas de Éster Carboxílico/metabolismoRESUMEN
Trehalase gene is mainly expressed in the digestive circulatory system for regulating energy metabolism and chitin synthesis in insects, but it is significantly expressed in gill for immunomodulation in shrimp. However, its function in regulating immunity, particularly metal resistance in crustaceans has yet to be elucidated. In this study, one Tre2 gene (NdTre2) was isolated from Neocaridina denticulata sinensis. It could bind to Cd2+ and inhibit its toxicity. Spatiotemporal expression analysis showed that the expression of NdTre2 was highest in the gill and significantly reduced at 12 h after Cd2+ stimulation. The transcriptomic analysis of the gill after NdTre2 knockdown showed that the expression of genes synthetizing 20E was up-regulated and the increased 20E could further induce apoptosis by activating the intrinsic mitochondrial pathway, exogenous death receptor-ligand pathway, and MAPK pathway. In vitro, overexpressing NdTre2 enhanced the tolerance of E. coli in Cd2+ environment. In summary, these results indicate that NdTre2 plays an essential role in regulating immunity and chitin metabolism in N. denticulata sinensis.
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Apoptosis , Cadmio , Trehalasa , Cadmio/toxicidad , Animales , Apoptosis/efectos de los fármacos , Trehalasa/metabolismo , Trehalasa/genética , Contaminantes Químicos del Agua/toxicidad , Decápodos/fisiología , Decápodos/genéticaRESUMEN
Cone beam computed tomography (CBCT) is widely employed in modern dentistry, and tooth segmentation constitutes an integral part of the digital workflow based on these imaging data. Previous methodologies rely heavily on manual segmentation and are time-consuming and labor-intensive in clinical practice. Recently, with advancements in computer vision technology, scholars have conducted in-depth research, proposing various fast and accurate tooth segmentation methods. In this review, we review 55 articles in this field and discuss the effectiveness, advantages, and disadvantages of each approach. In addition to simple classification and discussion, this review aims to reveal how tooth segmentation methods can be improved by the application and refinement of existing image segmentation algorithms to solve problems such as irregular morphology and fuzzy boundaries of teeth. It is assumed that with the optimization of these methods, manual operation will be reduced, and greater accuracy and robustness in tooth segmentation will be achieved. Finally, we highlight the challenges that still exist in this field and provide prospects for future directions.
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A novel rare earth complex, Eu(IAA)2(phen)2 (EuIP), was synthesized by solution-based synthesis method. Then, EuIP and polylactic acid (PLA) were melt-blended at 190 °C to obtain a multifunctional PLA/EuIP composite. The incorporation of EuIP provided PLA/EuIP composites with good light conversion ability. Under UV irradiation, PLA/EuIP composites converted the absorbed UV light into red light. Moreover, the PLA/1.0EuIP composite exhibited excellent light transmittance of 88 % in the visible region and showed strong red emission under UV light. After UV irradiation for 96 h, the molecular weights and mechanical properties of neat PLA decreased dramatically. Interestingly, the molecular weights and mechanical properties of PLA/EuIP composites did not deteriorate after 96 h of UV irradiation. The reason was that EuIP could absorb UV light and utilize the absorbed energy to emit red fluorescence. Furthermore, PLA/EuIP composites showed good antibacterial activities against E. coli and S. aureus. In addition, in vitro cell experiments showed that PLA/EuIP composites was suitable for the growth of murine breast cancer (4 T1) cells. Besides, enzymatic degradation testing also proved that PLA/EuIP composites had good biodegradability. This work provides an ingenious design strategy for the preparation of PLA/EuIP composites possessing light conversion ability, UV resistance, and antibacterial properties.
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Antibacterianos , Escherichia coli , Poliésteres , Rayos Ultravioleta , Poliésteres/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Animales , Ratones , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Línea Celular TumoralRESUMEN
The dental follicle (DF) plays an indispensable role in tooth eruption by regulating bone remodeling through their influence on osteoblast and osteoclast activity. The process of tooth eruption involves a series of intricate regulatory mechanisms and signaling pathways. Disruption of the parathyroid hormonerelated protein (PTHrP) in the PTHrPPTHrP receptor signaling pathway inhibits osteoclast differentiation by DF cells (DFCs), thus resulting in obstructed tooth eruption. Furthermore, parathyroid hormone receptor1 mutations are linked to primary tooth eruption failure. Additionally, the Wnt/ßcatenin, TGFß, bone morphogenetic protein and Hedgehog signaling pathways have crucial roles in DFC involvement in tooth eruption. DFC signal loss or alteration inhibits osteoclast differentiation, affects osteoblast and cementoblast differentiation, and suppresses DFC proliferation, thus resulting in failed tooth eruptions. Abnormal tooth eruption is also associated with a range of systemic syndromes and genetic diseases, predominantly resulting from pathogenic gene mutations. Among these conditions, the following disorders arise due to genetic mutations that disrupt DFCs and impede proper tooth eruption: Cleidocranial dysplasia associated with Runtrelated gene 2 gene mutations; osteosclerosis caused by CLCN7 gene mutations; mucopolysaccharidosis type VI resulting from arylsulfatase B gene mutations; enamel renal syndrome due to FAM20A gene mutations; and dentin dysplasia caused by mutations in the VPS4B gene. In addition, regional odontodysplasia and multiple calcific hyperplastic DFs are involved in tooth eruption failure; however, they are not related to gene mutations. The specific mechanism for this effect requires further investigation. To the best of our knowledge, previous reviews have not comprehensively summarized the syndromes associated with DF abnormalities manifesting as abnormal tooth eruption. Therefore, the present review aims to consolidate the current knowledge on DFC signaling pathways implicated in abnormal tooth eruption, and their association with disorders of tooth eruption in genetic diseases and syndromes, thereby providing a valuable reference for future related research.
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Saco Dental , Erupción Dental , Humanos , Saco Dental/metabolismo , Mutación , Transducción de Señal , Animales , Osteoclastos/metabolismo , Osteoclastos/patología , Receptor de Hormona Paratiroídea Tipo 1/metabolismo , Receptor de Hormona Paratiroídea Tipo 1/genética , Diferenciación Celular , Proteína Relacionada con la Hormona Paratiroidea/metabolismo , Proteína Relacionada con la Hormona Paratiroidea/genéticaRESUMEN
Immunoliposomes are made by conjugating antibodies or antibody fragments on liposome surfaces. Antibody fragments Fab', single-chain Fv fragments (scFv), or new constructs such as nanobodies are commonly used instead of whole IgGs for reduced risk immunogenicity. Here we described the preparation and characterization of immunoliposome-containing trastuzumab Fabs on the surface. The targeting ligand Fab-PEG-DSPE was synthesized by site-specific coupling between the C-terminal cysteine of the Fab and the maleimide group at the distal end of a DSPE-PEG. It was incorporated into preformed liposomes at 60 °C above the lipid bilayer phase transition temperature. The binding avidity of the immunoliposomes containing different Fab valencies was characterized using biolayer interferometry.
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Fragmentos de Inmunoglobulinas , Liposomas , Liposomas/química , Trastuzumab , Fragmentos Fab de Inmunoglobulinas/químicaRESUMEN
Oral cancer (OC), characterized by malignant tumors in the mouth, is one of the most prevalent malignancies worldwide. Chemotherapy is a commonly used treatment for OC; however, it often leads to severe side effects on human bodies. In recent years, nanotechnology has emerged as a promising solution for managing OC using nanomaterials and nanoparticles (NPs). Nano-drug delivery systems (nano-DDSs) that employ various NPs as nanocarriers have been extensively developed to enhance current OC therapies by achieving controlled drug release and targeted drug delivery. Through searching and analyzing relevant research literature, it was found that certain nano-DDSs can improve the therapeutic effect of drugs by enhancing drug accumulation in tumor tissues. Furthermore, they can achieve targeted delivery and controlled release of drugs through adjustments in particle size, surface functionalization, and drug encapsulation technology of nano-DDSs. The application of nano-DDSs provides a new tool and strategy for OC therapy, offering personalized treatment options for OC patients by enhancing drug delivery, reducing toxic side effects, and improving therapeutic outcomes. However, the use of nano-DDSs in OC therapy still faces challenges such as toxicity, precise targeting, biodegradability, and satisfying drug-release kinetics. Overall, this review evaluates the potential and limitations of different nano-DDSs in OC therapy, focusing on their components, mechanisms of action, and laboratory therapeutic effects, aiming to provide insights into understanding, designing, and developing more effective and safer nano-DDSs. Future studies should focus on addressing these issues to further advance the application and development of nano-DDSs in OC therapy.
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Silicone-rubber baby teats used to bottle-feed infants are frequently disinfected by moist heating. However, infant exposure to small microplastics (<10 µm) potentially released from the heated teats by hydrothermal decomposition has not been studied, owing to the limitations of conventional spectroscopy in visualizing microplastic formation and in characterizing the particles at the submicrometre scale. Here both the surfaces of silicone teats subjected to steam disinfection and the wash waters of the steamed teats were analysed using optical-photothermal infrared microspectroscopy. This new technique revealed submicrometre-resolved steam etching on and chemical modification of the teat surface. Numerous flake- or oil-film-shaped micro(nano)plastics (MNPs) (in the size range of 0.6-332 µm) presented in the wash waters, including cyclic and branched polysiloxanes or polyimides, which were generated by the steam-induced degradation of the base polydimethylsiloxane elastomer and the polyamide resin additive. The results indicated that by the age of one year, a baby could ingest >0.66 million elastomer-derived micro-sized plastics (MPs) (roughly 81% in 1.5-10 µm). Global MP emission from teat disinfection may be as high as 5.2 × 1013 particles per year. Our findings highlight an entry route for surface-active silicone-rubber-derived MNPs into both the human body and the environment. The health and environmental risks of the particles are as yet unknown.
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Desinfección , Microplásticos , Imagen Óptica , Elastómeros de Silicona/química , Espectrofotometría Infrarroja , Vapor , Temperatura , Dimetilpolisiloxanos/química , Humanos , Imidas/química , Lactante , Resinas Sintéticas/químicaRESUMEN
Lotus-like Ni@NiO embedded porous carbons (Ni@NiO/PCs) were fabricated by pyrolysis of MOF-74/cellulose nanocrystal hybrids, and used as a solid phase microextraction (SPME) coating for ultrasensitive determination of chlorobenzenes (CBs) from water combined with gas chromatography-mass spectrometry. Owing to its abundant chemical groups, high porosity, and excellent thermal stability, the as-prepared Ni@NiO/PCs presented superior extraction performance compared to commercial SPME coatings. Notably, Ni@NiO/PCs derived from MOF-74/CNC hybrids presented higher extraction efficiencies towards CBs than that derived from pristine CNC and MOF-74 due to the formation of micro/mesopores and more abundant oxygen-containing groups. Under the optimum extraction conditions, the proposed analytical method presented wide linearity range (0.5-1500 ng L-1), ultra-low detection of limit (0.005-0.049 ng L-1), and excellent precision with relative standard deviations of 4.7-9.2% for a single fiber and 8.8-10.9% for 5 fibers, and long lifetime (≥160 times). The proposed analytical method was finally applied for determination of CBs from real water samples, and the recoveries were in the range of 93.2-116.8% towards eight CBs. This study delivered a novel and efficient sorbent as SPME coating to extraction and determination of CBs from water.
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Lotus , Nanopartículas , Contaminantes Químicos del Agua , Carbono , Celulosa , Clorobencenos , Nanopartículas/análisis , Porosidad , Microextracción en Fase Sólida/métodos , Agua/química , Contaminantes Químicos del Agua/análisisRESUMEN
Concomitant with the promotion of industrial transformation, sustainable development strategies, and accelerated urbanization, there has been an increase in the number of industrial relic restoration projects. However, there are many disputes over the value and development of such industrial relic restoration projects. In this work, we identified three evaluation indicators based on a study of 106 industrial relic restoration projects in China. A value assessment model composed of five parts combining the Delphi method and analytic hierarchy process was established. The results show that an effective assessment of the value of industrial relic restoration projects can enable the effective use of green technology, reduce construction costs, protect industrial heritage, and inherit historical culture. In addition, there are many uncertain factors in developing these projects, such as brownfield pollution and dilapidated buildings, and appropriate renewal strategies can reduce safety risks as well as maximize the heritage value. As there is limited research assessing the value of industrial relic restoration projects in China, our study can serve as a reference for the value assessment of existing building restoration projects including historical blocks and livable villages.