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1.
Nature ; 628(8008): 576-581, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38570677

RESUMO

The dual jaw joint of Morganucodon1,2 consists of the dentary-squamosal joint laterally and the articular-quadrate one medially. The articular-quadrate joint and its associated post-dentary bones constitute the precursor of the mammalian middle ear. Fossils documenting the transition from such a precursor to the mammalian middle ear are poor, resulting in inconsistent interpretations of this hallmark apparatus in the earliest stage of mammaliaform evolution1-5. Here we report mandibular middle ears from two Jurassic mammaliaforms: a new morganucodontan-like species and a pseudotribosphenic shuotheriid species6. The morganucodontan-like species shows many previously unknown post-dentary bone morphologies1,2 and exhibits features that suggest a loss of load-bearing function in its articular-quadrate joint. The middle ear of the shuotheriid approaches the mammalian condition in that it has features that are suitable for an exclusively auditory function, although the post-dentary bones are still attached to the dentary. With size reduction of the jaw-joint bones, the quadrate shifts medially at different degrees in relation to the articular in the two mammaliaforms. These changes provide evidence of a gradual loss of load-bearing function in the articular-quadrate jaw joint-a prerequisite for the detachment of the post-dentary bones from the dentary7-12 and the eventual breakdown of the Meckel's cartilage13-15 during the evolution of mammaliaforms.


Assuntos
Evolução Biológica , Orelha Média , Fósseis , Arcada Osseodentária , Mamíferos , Articulação Temporomandibular , Animais , Orelha Média/anatomia & histologia , Arcada Osseodentária/anatomia & histologia , Mamíferos/anatomia & histologia , Mamíferos/classificação , Mandíbula/anatomia & histologia , Articulação Temporomandibular/anatomia & histologia
2.
Proc Natl Acad Sci U S A ; 120(33): e2305704120, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549277

RESUMO

Biocompatible and morphable hydrogels capable of multimode reprogrammable, and adaptive shape changes are potentially useful for diverse biomedical applications. However, existing morphable systems often rely on complicated structural designs involving cumbersome and energy-intensive fabrication processes. Here, we report a simple electric-field-activated protein network migration strategy to reversibly program silk-protein hydrogels with controllable and reprogrammable complex shape transformations. The application of a low electric field enables the convergence of net negatively charged protein cross-linking networks toward the anode (isoelectric point plane) due to the pH gradient generated in the process, facilitating the formation of a gradient network structure and systems suitable for three-dimensional shape change. These tunable protein networks can be reprogrammed or permanently fixed by control of the polymorphic transitions. We show that these morphing hydrogels are capable of conformally interfacing with biological tissues by programming the shape changes and a bimorph structure consisting of aligned carbon nanotube multilayers and the silk hydrogels was assembled to illustrate utility as an implantable bioelectronic device for localized low-voltage electrical stimulation of the sciatic nerve in a rabbit.


Assuntos
Hidrogéis , Seda , Animais , Coelhos , Seda/química , Hidrogéis/química , Ponto Isoelétrico , Materiais Biocompatíveis/química
3.
Mol Pharm ; 21(2): 781-790, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38153044

RESUMO

There is an urgent need to develop efficient treatments for highly invasive triple-negative breast cancer (TNBC) with a high rate of postoperative. Baicalin (BA) has shown inhibitory effects on several tumor cells and could activate ferroptosis in some tumor cells by producing reactive oxygen species (ROS). For overcoming the shortcomings of BA in clinical applications and enhancing the effect of ferroptosis in TNBC, herein, a multifunctional liposome (BA-Fe(III) coordination-polymer-loaded liposome, BA-Fe(III) Lipo) was developed for synergistic chemotherapy of TNBC with ferroptosis activation. Fe(III) released from BA-Fe(III) Lipo could be efficiently reduced to Fe(II) in the presence of high glutathione in tumor microenvironment, which in turn catalyzed the oxidation of unsaturated fats through lipid peroxidation for more ROS production. In addition, BA-Fe(III) Lipo activated tumor cell ferroptosis by down-regulating the enzymatic activity of ferritin heavy chain 1 protein and glutathione peroxidase. This study provided a novel therapeutic strategy for the treatment of TNBC by ingeniously combining chemotherapy with the activation of ferroptosis, which presented potential clinical applications.


Assuntos
Ferroptose , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Lipossomos , Compostos Férricos , Espécies Reativas de Oxigênio , Glutationa , Linhagem Celular Tumoral , Microambiente Tumoral
4.
Biomacromolecules ; 25(2): 924-940, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38156632

RESUMO

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.


Assuntos
Glicoproteínas , Polietilenos , Polifenóis , Polipropilenos , Ácido Tióctico , Adesivos , Poloxâmero , Lipopolissacarídeos , Cicatrização , Hidrogéis/farmacologia , Anti-Inflamatórios , Antibacterianos
5.
Environ Sci Technol ; 58(21): 9091-9101, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38709279

RESUMO

People of all ages consume salt every day, but is it really just salt? Plastic nanoparticles [nanoplastics (NPs)] pose an increasing environmental threat and have begun to contaminate everyday salt in consumer goods. Herein, we developed a combined surface enhanced Raman scattering (SERS) and stimulated Raman scattering (SRS) approach that can realize the filtration, enrichment, and detection of NPs in commercial salt. The Au-loaded (50 nm) anodic alumina oxide substrate was used as the SERS substrate to explore the potential types of NP contaminants in salts. SRS was used to conduct imaging and quantify the presence of the NPs. SRS detection was successfully established through standard plastics, and NPs were identified through the match of the hydrocarbon group of the nanoparticles. Simultaneously, the NPs were quantified based on the high spatial resolution and rapid imaging of the SRS imaging platform. NPs in sea salts produced in Asia, Australasia, Europe, and the Atlantic were studied. We estimate that, depending on the location, an average person could be ingesting as many as 6 million NPs per year through the consumption of sea salt alone. The potential health hazards associated with NP ingestion should not be underestimated.


Assuntos
Análise Espectral Raman , Plásticos , Nanopartículas , Cloreto de Sódio/química
6.
Ecotoxicol Environ Saf ; 280: 116540, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38833982

RESUMO

The widespread utilization of polyethylene terephthalate (PET) has caused a variety of environmental and health problems. Compared with traditional thermomechanical or chemical PET cycling, the biodegradation of PET may offer a more feasible solution. Though the PETase from Ideonalla sakaiensis (IsPETase) displays interesting PET degrading performance under mild conditions; the relatively low thermal stability of IsPETase limits its practical application. In this study, enzyme-catalysed PET degradation was investigated with the promising IsPETase mutant HotPETase (HP). On this basis, a carbohydrate-binding module from Bacillus anthracis (BaCBM) was fused to the C-terminus of HP to construct the PETase mutant (HLCB) for increased PET degradation. Furthermore, to effectively improve PET accessibility and PET-degrading activity, the truncated outer membrane hybrid protein (FadL) was used to expose PETase and BaCBM on the surface of E. coli (BL21with) to develop regenerable whole-cell biocatalysts (D-HLCB). Results showed that, among the tested small-molecular weight ester compounds (p-nitrophenyl phosphate (pNPP), p-Nitrophenyl acetate (pNPA), 4-Nitrophenyl butyrate (pNPB)), PETase displayed the highest hydrolysing activity against pNPP. HP displayed the highest catalytic activity (1.94 µM(p-NP)/min) at 50 °C and increased longevity at 40 °C. The fused BaCBM could clearly improve the catalytic performance of PETase by increasing the optimal reaction temperature and improving the thermostability. When HLCB was used for PET degradation, the yield of monomeric products (255.7 µM) was ∼25.5 % greater than that obtained after 50 h of HP-catalysed PET degradation. Moreover, the highest yield of monomeric products from the D-HLCB-mediated system reached 1.03 mM. The whole-cell catalyst D-HLCB displayed good reusability and stability and could maintain more than 54.6 % of its initial activity for nine cycles. Finally, molecular docking simulations were utilized to investigate the binding mechanism and the reaction mechanism of HLCB, which may provide theoretical evidence to further increase the PET-degrading activities of PETases through rational design. The proposed strategy and developed variants show potential for achieving complete biodegradation of PET under mild conditions.


Assuntos
Biodegradação Ambiental , Burkholderiales , Escherichia coli , Polietilenotereftalatos , Polietilenotereftalatos/química , Polietilenotereftalatos/metabolismo , Burkholderiales/enzimologia , Escherichia coli/genética , Bacillus anthracis/enzimologia , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Engenharia de Proteínas
7.
Biomacromolecules ; 24(4): 1675-1688, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-36867105

RESUMO

Although some commercial excipients for improving the solubility of highly crystalline drugs are widely used, they still cannot cover all types of hydrophobic drugs. In this regard, with phenytoin as the target drug, related molecular structures of polymer excipients were designed. The optimal repeating units of NiPAm and HEAm were screened out through quantum mechanical simulation and Monte Carlo simulation methods, and the copolymerization ratio was also determined. Using molecular dynamics simulation technology, it was confirmed that the dispersibility and intermolecular hydrogen bonds of phenytoin in the designed copolymer were better than those in the commercial PVP materials. At the same time, the designed copolymers and solid dispersions were also prepared during the experiment, and the improvement of their solubility was confirmed, which is in accordance with the simulation predictions. The new ideas and simulation technology may be used for drug modification and development.


Assuntos
Excipientes , Polímeros , Ligação de Hidrogênio , Polímeros/química , Excipientes/química , Fenitoína/química , Solubilidade
8.
Environ Sci Technol ; 57(21): 8139-8148, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37194262

RESUMO

The eco-corona on microplastics refers to the initial layer of biomolecular compounds adsorbed onto the surface after environmental exposure. The formation and composition of the eco-corona in soils have attracted relatively little attention; however, the eco-corona has important implications for the fate and impacts of microplastics and co-occurring chemical contaminants. Here, it was demonstrated that the formation of the eco-corona on polyethylene microplastics exposed to water-extractable soil metabolites (WESMs) occurs quite rapidly via two pathways: direct adsorption of metabolites on microplastics and bridging interactions mediated by macromolecules. The main eco-corona components were common across all soils and microplastics tested and were identified as lipids and lipid-like molecules, phenylpropanoids and polyketides, nucleosides, nucleotides, and their analogues. WESMs were found to reduce the adsorption of co-occurring organic contaminants to microplastics by two pathways: reduced adsorption to the eco-corona surface and co-solubilization in the surrounding water. These impacts from the eco-corona and the soil metabolome should be considered within fate and risk assessments of microplastics and co-occurring contaminants.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Adsorção , Solo , Poluentes Químicos da Água/análise , Metaboloma
9.
Curr Microbiol ; 80(5): 159, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37004682

RESUMO

Hand foot and mouth disease (HFMD) is a contagious and seasonal viral disease in children. The gut microbiota of HFMD children is not clear now. The study aimed to explore the gut microbiota of HFMD children. The 16S rRNA gene of the gut microbiota of ten HFMD patients and ten healthy children were sequenced on the NovaSeq and PacBio platforms respectively. There were significant differences in gut microbiota between the patients and healthy children. The diversity and abundance of gut microbiota in HFMD patients were lower than that in healthy children. The species Roseburia inulinivorans and Romboutsia timonensis were more abundant in healthy children than those in HFMD patients, which suggests that the two species may be used as probiotics for adjusting the gut microbiota of HFMD patients. Meanwhile, the results of 16S rRNA gene sequences from the two platforms were different. The NovaSeq platform identified more microbiota and has the characteristics of high throughput, short time and low price. However, the NovaSeq platform has low resolution at the species level. The PacBio platform has high resolution based on its long reads length, which is more suitable for species-level analysis. But, the shortcomings of the high price and low throughput of PacBio still need to be overcome. With the development of sequencing technology, the reduction in sequencing price and the increase in throughput will promote the third-generation sequencing technology used in the study of gut microbes.


Assuntos
Microbioma Gastrointestinal , Doença de Mão, Pé e Boca , Microbiota , Humanos , Criança , Microbioma Gastrointestinal/genética , RNA Ribossômico 16S/genética , Genes de RNAr , Doença de Mão, Pé e Boca/genética , Microbiota/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos
10.
Ecotoxicol Environ Saf ; 259: 115009, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37182302

RESUMO

Microplastics and antibiotics are two common pollutants in the ocean. However, due to changes of salinity and temperature in the ocean, their interaction are significantly different from that of fresh water, and the mechanism remains unclear. Here, the interactions of sulfamethoxazole (SMZ) and microplastics were studied at different temperatures and salinities. The saturation adsorption capacity of SMZ in polypropylene (PP), polyethylene (PE), styrene (PS), polyvinyl chloride (PVC), and synthetic resins (ABS) were highest at the temperature of 20 °C, with 0.118 ± 0.002 mg·g-1, 0.106 ± 0.004 mg·g-1, 0.083 ± 0.002 mg·g-1, 0.062 ± 0.007 mg·g-1 and 0.056 ± 0.003 mg·g-1, respectively. The effect of temperature reduction is more significant than temperature rise. The intraparticle diffusion model is appropriate to PP, when film diffusion model suited for PS. The salinity has a more significant effect than temperature on different microplastics, due to the electrostatic adsorption and iron exchange. With the increase in salinity from 0.05% to 3.5%, the adsorption capacity of microplastics on SMZ fell by 53.3 ± 5%, and there was no discernible difference of various microplastics. The hydrogen bond and π-π conjugation of microplastics play an important role in the adsorption of SMZ. These findings further deepen the understanding of the interaction between microplastics and antibiotics in the marine environment.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos/química , Sulfametoxazol/química , Temperatura , Salinidade , Polipropilenos/química , Polietileno/química , Antibacterianos , Adsorção , Poluentes Químicos da Água/análise
11.
Am J Forensic Med Pathol ; 44(4): 345-349, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37549028

RESUMO

ABSTRACT: 1,2-Dichloropropane (1,2-DCP) is a common industrial solvent and chemical intermediate that can cause acute poisoning to humans through exposure during its production and industrial use. The target organs of 1,2-DCP include the eyes, respiratory system, liver, kidney, central nervous system, and skin. Forensic identification of 1,2-DCP poisoning is difficult because of the lack of characteristic pathological changes. This article reports an autopsy case of acute 1,2-DCP poisoning caused by self-ingestion of rubber cement. A woman developed seizures and coagulation dysfunction after ingesting approximately 10 mL of rubber cement and died 43 hours later. Autopsy revealed generalized subcutaneous hemorrhage, cardiopulmonary multifocal hemorrhage, bronchopneumonia, severe cerebral edema, focal hepatic necrosis, granular deposition in the glomerular capsule and renal tubules, and delipidation of the adrenal cortex. These findings indicate that 1,2-DCP poisoning can induce central nervous system dysfunction, respiratory system damage, liver and kidney function damage, hemolytic anemia, disseminated intravascular coagulation, and adrenal damage. This case may provide useful perspectives for forensic identification of 1,2-DCP poisoning in the future.


Assuntos
Hidrocarbonetos Clorados , Intoxicação , Feminino , Humanos , Autopsia , Borracha , Hemorragia , Ingestão de Alimentos
12.
Sensors (Basel) ; 23(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36904858

RESUMO

Straight bevel gears are widely used in mining equipment, ships, heavy industrial equipment, and other fields due to their high capacity and robust transmission. Accurate measurements are essential in order to determine the quality of bevel gears. We propose a method for measuring the accuracy of the top surface profile of the straight bevel gear teeth based on binocular visual technology, computer graphics, error theory, and statistical calculations. In our method, multiple measurement circles are established at equal intervals from the small end of the top surface of the gear tooth to the large end, and the coordinates of the intersection points of these circles with the tooth top edge lines of the gear teeth are extracted. The coordinates of these intersections are fitted to the top surface of the tooth based on NURBS surface theory. The surface profile error between the fitted top surface of the tooth and the designed surface is measured and determined based on the product use requirements, and if this is less than a given threshold, the product is acceptable. With a module of 5 and an eight-level precision, such as the straight bevel gear, the minimum surface profile error measured was -0.0026 mm. These results demonstrate that our method can be used to measure surface profile errors in the straight bevel gears, which will broaden the field of in-depth measurements for the straight bevel gears.

13.
Nano Lett ; 22(9): 3691-3698, 2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35451303

RESUMO

Synthetic polymer-derived hollow carbon spheres have great utilitarian value in many fields for which the synthesis of proper polymer precursors is a key process. The exploration of new suitable polymer precursors and the construction of refined hollow structures in emerging polymers are both of great significance for synthetic methodology and novel carbon materials. Here, for the first time Schiff base polymer (SBP) colloid spheres with refined hollow structures were synthesized by tandem gradient growth and confined polymerization processes. The Hill equation was employed as a mathematical model to explain the gradient growth of SBP spheres. The size-dependent inner structure of SBP spheres can be adjusted from hollow to multichamber-surrounded hollow, and then to a multichamber structure. SBP-derived carbon spheres having similar surface area and chemical composition but different inner structures provide an effective way to investigate the relationship between inner structure and performance.


Assuntos
Carbono , Polímeros , Carbono/química , Microesferas , Polimerização , Polímeros/química , Bases de Schiff
14.
Int J Mol Sci ; 24(8)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37108543

RESUMO

Microplastics have become a new type of environmental pollutant that can accumulate in various tissues and organs of the body and cause chronic damage. In this study, two different size polystyrene microplastics (PS-MPs, 5 µm and 0.5 µm) exposure models were established in mice to investigate the effects of PS-MPs with different particle sizes on oxidative stress in the liver. The results showed that PS-MPs exposure caused a decrease in body weight and liver-to-body weight. The hematoxylin and eosin staining and transmission electron microscopy results showed that exposure to PS-MPs led to the disorganized cellular structure of liver tissue, nuclear crinkling, and mitochondrial vacuolation. The extent of damage in the 5 µm PS-MP exposure group was more extensive when compared with the other group. The evaluation of oxidative-stress-related indicators showed that PS-MPs exposure exacerbated oxidative stress in hepatocytes, especially in the 5 µm PS-MPs group. The expression of oxidative-stress-related proteins sirtuin 3(SIRT3) and superoxide dismutase (SOD2) was significantly reduced, and the reduction was more pronounced in the 5 µm PS-MPs group. In conclusion, PS-MPs exposure led to oxidative stress in mouse hepatocytes and caused more severe damage in the 5 µm PS-MPs group when compared with the 0.5 µm PS-MPs group.


Assuntos
Poliestirenos , Poluentes Químicos da Água , Camundongos , Animais , Poliestirenos/farmacologia , Microplásticos/toxicidade , Plásticos/metabolismo , Estresse Oxidativo , Hepatócitos/metabolismo , Poluentes Químicos da Água/farmacologia
15.
J Periodontal Res ; 57(4): 869-879, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35730345

RESUMO

BACKGROUND AND OBJECTIVE: Periodontitis is a chronic progressive inflammation that invades periodontal supporting tissues, in which periodontal tissue regeneration engineering offers new hope for prevention and treatment, including seed cells, scaffolds, and growth factors. In recent years, scholars have shown that autologous teeth can be used as new bone tissue repair materials for periodontal regeneration and bone tissue repair. The aim of this study was to establish a human periodontal ligament cell line that expresses the human bone morphogenetic protein 2 gene (BMP2) in a stable manner using lentiviral mediation in order to explore the effect of BMP2 from autologous tooth on the proliferative and osteogenic capacity of human periodontal ligament cells (hPDLCs). MATERIALS AND METHODS: Human periodontal ligament cells were cultured, subcultured, and identified, and then homologous recombinant lentivirus plasmid plv-BMP2 was constructed and transfected into the third passage (P3 ) hPDLCs. After that, the effect of BMP2 on its proliferation was detected by CCK-8, at the same time, the osteogenic induction of hPDLCs was carried out at 7, 14, and 21 days, and then the effect of BMP2 on its osteogenic ability was detected by alizarin red staining, alkaline phosphatase activity determination, and the mRNA expression levels of osteogenic-related genes using real-time fluorescence quantitative PCR, including alkaline phosphatase, runt-related transcription factor 2, bone sialoprotein, osteocalcin, osteopontin, and collagen I. Finally, spss26.0 software was used for statistical processing. RESULTS: The results showed that cells transfected with the homologous recombinant lentiviral plasmid pLV-BMP2 had a similar morphology to normal hPDLCs, showing a typical radial arrangement; the cell proliferative capacity of the pLV-BMP2 group as measured by CCK-8 was enhanced compared with the control group and the pLV-puro group (p < .05); alizarin red staining and alkaline phosphatase activity assay showed that the osteogenic ability of pLV-BMP2 was significantly enhanced compared with the control and pLV-puro groups (p < .01), and the findings of real-time fluorescence-based quantitative PCR showed high expression of osteogenic-related genes in pLV-BMP2 group (p < .01). CONCLUSION: In conclusion, a stable periodontal ligament cell line overexpressing BMP2 was successfully established by a lentivirus-mediated method, which proved that BMP2 has a strong ability to promote the proliferation and osteogenesis of hPDLCs, thereby providing an opportunity for the study of periodontal tissue regeneration as well as providing an experimental basis for the application of autologous teeth as a new type of bone repair material for periodontal therapy and even for maxillofacial bone tissue repair.


Assuntos
Osteogênese , Ligamento Periodontal , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Proteína Morfogenética Óssea 2/farmacologia , Diferenciação Celular , Células Cultivadas , Humanos , Lentivirus/genética , Lentivirus/metabolismo , Osteogênese/genética , Sincalida/metabolismo , Sincalida/farmacologia
16.
Sensors (Basel) ; 22(18)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36146225

RESUMO

Earthquakes threaten humanity globally in complex ways that mainly include various socioeconomic consequences of life and property losses. Resilience against seismic risks is of high importance in the modern world and needs to be sustainable. Sustainable earthquake resilience (SER) from the perspective of structural engineering means equipping the built environment with appropriate aseismic systems. Shape memory alloys (SMAs) are a class of advanced materials well suited for fulfilling the SER demand of the built environment. This article explores how this capability can be realized by the innovative SMA-based superelasticity-assisted slider (SSS), recently proposed for next-generation seismic protection of structures. The versatility of SSS is first discussed as a critical advantage for an effective SER. Alternative configurations and implementation styles of the system are presented, and other advantageous features of this high-tech isolation system (IS) are studied. Results of shaking table experiments, focused on investigating the expected usefulness of SSS for seismic protection in hospitals and conducted at the structural earthquake engineering laboratory of the University of Bonab, are then reported. SSS is compared with currently used ISs, and it is shown that SSS provides the required SER for the built environments and outperforms other ISs by benefitting from the pioneered utilization of SMAs in a novel approach.


Assuntos
Terremotos , Ligas de Memória da Forma
17.
Int J Mol Sci ; 23(22)2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36430889

RESUMO

Cadmium (Cd) is a potential pathogenic factor in the urinary system that is associated with various kidney diseases. Microplastics (MPs), comprising of plastic particles less than 5 mm in diameter, are a major carrier of contaminants. We applied 10 mg/L particle 5 µm MPs and 50 mg/L CdCl2 in water for three months in vivo assay to assess the damaging effects of MPs and Cd exposure on the kidney. In vivo tests showed that MPs exacerbated Cd-induced kidney injury. In addition, the involvement of oxidative stress, autophagy, apoptosis, and fibrosis in the damaging effects of MPs and Cd on mouse kidneys were investigated. The results showed that MPs aggravated Cd-induced kidney injury by enhancing oxidative stress, autophagy, apoptosis, and fibrosis. These findings provide new insights into the toxic effects of MPs on the mouse kidney.


Assuntos
Cádmio , Microplásticos , Animais , Camundongos , Cádmio/toxicidade , Plásticos , Autofagia , Apoptose , Estresse Oxidativo , Rim , Fibrose
18.
J Xray Sci Technol ; 30(1): 195-206, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34719475

RESUMO

OBJECTIVE: To assess reliability of cone-beam CT (CBCT) for nasolabial soft tissue measurements in patients with skeletal class III malocclusion based on 3-dimensional (3D) facial scanner results. METHODS: CBCT and 3D facial scan images of 20 orthognathic patients are used in this study. Eleven soft tissue landmarks and 15 linear and angular measurements are identified and performed. For qualitative evaluation, Shapiro-Wilk test and Bland-Altman plots are applied to analyze the equivalence of the measurements derived from these two kinds of images. To quantify specific deviation of CBCT measurements from facial scanner, the latter is set as a benchmark, and mean absolute difference (MAD) and relative error magnitude (REM) for each variable are also calculated. RESULTS: Statistically significant differences are observed in regions of nasal base and lower lip vermilion between two methods. MAD value for all length measurements are less than 2 mm and for angular variables < 8°. The average MAD and REM for length measurements are 0.94 mm and 5.64%, and for angular measurements are 2.27° and 3.78%, respectively. CONCLUSIONS: The soft tissue results measured by CBCT show relatively good reliability and can be used for 3D measurement of soft tissue in the nasolabial region clinically.


Assuntos
Má Oclusão Classe III de Angle , Cefalometria/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Face/anatomia & histologia , Face/diagnóstico por imagem , Humanos , Imageamento Tridimensional/métodos , Má Oclusão Classe III de Angle/diagnóstico por imagem , Reprodutibilidade dos Testes
19.
Mol Pharm ; 18(10): 3862-3870, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34470216

RESUMO

In this work, dimeric artesunate-phosphatidylcholine conjugate (dARTPC)-based liposomes encapsulated with irinotecan (Ir) were developed for anticancer combination therapy. First, dARTPC featured with unique amphipathic properties formed liposomes by classical thin-film methods. After that, Ir was encapsulated into dARTPC-based liposomes (Ir/dARTPC-LP) by the triethylammonium sucrose octasulfate gradient method. Physicochemical characterization indicated that Ir/dARTPC-LP had a mean size of around 140 nm and a negative ζ potential of approximately -30 mV. Most noticeably, liposomes displayed an encapsulation efficiency of greater than 98% with a controllable drug loading of 4-22%. The in vitro release of dihydroartemisinin (DHA) and Ir from Ir/dARTPC-LP was investigated by dialysis in different media. It was found that effective release of both DHA (65.42%) and Ir (77.28%) in a weakly acidic medium (pH 5.0) after 48 h was achieved in comparison to very slow release under a neutral environment (DHA 9.90% and Ir 8.72%), indicating the controllable release of both drugs. Confocal laser scanning microscopy confirmed the improved cellular internalization of Ir/dARTPC-LP. The cytotoxicity of Ir/dARTPC-LP was evaluated in the MCF-7, A549, and HepG2 cell lines. The results showed that Ir/dARTPC-LP had significant synergistic efficacy in the loss of cell growth. In vivo anticancer evaluation was performed using a 4T1 xenograft tumor model. Ir/dARTPC-LP had a high tumor inhibition rate of 62.7% without significant toxicity in comparison with the injection of Ir solution. Taken together, dARTPC encapsulated with Ir has great potential for anticancer combination therapy.


Assuntos
Artesunato/administração & dosagem , Sistemas de Liberação de Medicamentos , Irinotecano/administração & dosagem , Lipossomos/administração & dosagem , Animais , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptose/efeitos dos fármacos , Artesunato/farmacocinética , Artesunato/uso terapêutico , Linhagem Celular Tumoral , Combinação de Medicamentos , Sistemas de Liberação de Medicamentos/métodos , Feminino , Irinotecano/farmacocinética , Irinotecano/uso terapêutico , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Neoplasias Experimentais/tratamento farmacológico , Fosfatidilcolinas
20.
Nanotechnology ; 32(5): 055101, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33059341

RESUMO

Graphene and its derivatives have shown fascinating potential in biomedical applications. However, the biocompatibility of graphene with vascular smooth muscle cells (VSMCs) and applications to vascular engineering have not been explored extensively. Using a rat aortic smooth muscle cell line, A7r5, as a VSMC model, we have explored the effects of graphene oxide (GO) on the growth and behaviours of VSMCs. Results demonstrated that GO had no obvious toxicity to VSMCs. Cells cultured on GO retained the expression of smooth muscle cell-specific markers CNN1, ACTA2 and SMTN, on both mRNA and protein levels. A wound healing assay demonstrated no effect of GO on cell migration. We also found that small-flaked GO favoured the proliferation of VSMCs, suggesting a potential of using surface chemistry or physical properties of GO to influence cell growth behaviour. These results provide insight into the suitability of GO as a scaffold for vascular tissue engineering.


Assuntos
Materiais Biocompatíveis/farmacologia , Grafite/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Animais , Biomarcadores/metabolismo , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Teste de Materiais , Modelos Biológicos , Ratos
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