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1.
Nat Mater ; 22(7): 873-879, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37231245

RESUMEN

The interconversion between electrical and mechanical energies is pivotal to ferroelectrics to enable their applications in transducers, actuators and sensors. Ferroelectric polymers exhibit a giant electric-field-induced strain (>4.0%), markedly exceeding the actuation strain (≤1.7%) of piezoelectric ceramics and crystals. However, their normalized elastic energy densities remain orders of magnitude smaller than those of piezoelectric ceramics and crystals, severely limiting their practical applications in soft actuators. Here we report the use of electro-thermally induced ferroelectric phase transition in percolative ferroelectric polymer nanocomposites to achieve high strain performance in electric-field-driven actuation materials. We demonstrate a strain of over 8% and an output mechanical energy density of 11.3 J cm-3 at an electric field of 40 MV m-1 in the composite, outperforming the benchmark relaxor single-crystal ferroelectrics. This approach overcomes the trade-off between mechanical modulus and electro-strains in conventional piezoelectric polymer composites and opens up an avenue for high-performance ferroelectric actuators.


Asunto(s)
Electricidad , Nanocompuestos , Polímeros
2.
Photochem Photobiol Sci ; 23(4): 629-650, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38512633

RESUMEN

This Assessment Update by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) considers the interactive effects of solar UV radiation, global warming, and other weathering factors on plastics. The Assessment illustrates the significance of solar UV radiation in decreasing the durability of plastic materials, degradation of plastic debris, formation of micro- and nanoplastic particles and accompanying leaching of potential toxic compounds. Micro- and nanoplastics have been found in all ecosystems, the atmosphere, and in humans. While the potential biological risks are not yet well-established, the widespread and increasing occurrence of plastic pollution is reason for continuing research and monitoring. Plastic debris persists after its intended life in soils, water bodies and the atmosphere as well as in living organisms. To counteract accumulation of plastics in the environment, the lifetime of novel plastics or plastic alternatives should better match the functional life of products, with eventual breakdown releasing harmless substances to the environment.


Asunto(s)
Plásticos , Contaminantes Químicos del Agua , Humanos , Plásticos/toxicidad , Ecosistema , Rayos Ultravioleta , Cambio Climático , Contaminantes Químicos del Agua/análisis
3.
J Periodontal Res ; 59(2): 311-324, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38082497

RESUMEN

BACKGROUND AND OBJECTIVES: Periodontitis is an immuno-inflammatory disease caused by dental plaque biofilms and inflammations. The regeneration of bone tissue in inflammatory environment is of great significance for the treatment of periodontal disease, but the specific molecular mechanism of bone formation in periodontitis still needs further exploration. The objective of this study was to identify key osteogenesis-related genes (ORGs) in periodontitis. METHODS: We used two datasets from the Gene Expression Omnibus (GEO) database to find differentially expressed mRNAs and miRNAs, further performed Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Then we predicted the downstream genes of the differentially expressed miRNAs (DEMs) by the TargetScan database and established a miRNA-mRNA regulatory network. Finally, the osteogenic mechanism of periodontitis was explored through quantitative real-time PCR (qRT-PCR) by inducing inflammatory environment and osteogenic differentiation of hPDLSCs. RESULTS: Through differential expression analysis and prediction of downstream target genes of DEMs, we created a miRNA-mRNA regulatory network consisting of 29 DEMs and 11 differentially expressed osteogenesis-related genes (DEORGs). In addition, the qRT-PCR results demonstrated that BTBD3, PLAT, AKAP12, SGK1, and GLCE expression levels were significantly upregulated, while those of TIMP3, ZCCHC14, LIN7A, DNAH6, NNT, and ITGA6 were downregulated under the dual effects of inflammatory stimulation and osteogenic induction. CONCLUSION: DEORGs might be important factors in the osteogenic phase of periodontitis, and the miRNA-mRNA network may shed light on the clarification of the role and mechanism of osteogenesis in periodontitis and contribute to the development of novel therapeutic strategies.


Asunto(s)
MicroARNs , Periodontitis , Humanos , Osteogénesis/genética , Ligamento Periodontal , Células Madre , Diferenciación Celular/genética , Periodontitis/genética , Periodontitis/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Células Cultivadas , Proteínas de la Membrana/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas de Transporte Vesicular/farmacología , Proteínas del Tejido Nervioso/metabolismo
4.
BMC Musculoskelet Disord ; 25(1): 294, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627655

RESUMEN

PURPOSE: To assess the clinical safety, accuracy, and efficacy of percutaneous kyphoplasty (PKP) surgery using an enhanced method of unilateral puncture on the convex side for the treatment of painful osteoporotic vertebral compression fractures (P-OVCF) with scoliosis. METHODS: Clinical and radiographic data of P-OVCF patients with scoliosis who underwent PKP via unilateral puncture on the convex side from January 2018 to December 2021 were retrospectively analyzed. This technique's detailed surgical steps and tips were described. The local kyphosis angle (LKA), scoliosis Cobb angle (SCA), and local scoliosis Cobb angle (LSCA) were measured using X-ray and compared at pre-operation, post-operation, and the last follow-up. The width of pedicle (POW), inner inclination angle (IIA), lateral distance (LD), and puncture course length (PCL) were measured on the axial computed tomography image and compared between two sides. Postoperative computed tomography was employed to evaluate the condition of cement distribution and puncture. Clinical outcomes were evaluated using the Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) for back pain (BP). RESULTS: Thirty-six patients, 23 women and 13 men, with an average age of 76.31 ± 6.28 years were monitored for 17.69 ± 4.70 months. The median surgical duration of single vertebrae was 35 min. The volume of bone cement for single vertebrae was 3.81 ± 0.87 ml and the proportion of sufficient cement distribution of the patients was 97.22. LKA was considerably improved from pre-operation to post-operation and sustained at the last follow-up. SCA and LSCA were not significantly modified between these three-time points. IIA, PCL, and LD were lower on the convex side than on the concave side. POW was considerably wider on the convex side. The ODI and VAS-BP scores were significantly improved after surgery and sustained during the follow-up. CONCLUSIONS: Combining with the proper assessment of the pre-injured life status of patients, PKP surgery using unilateral puncture on the convex side for the treatment of P-OVCF with scoliosis can achieve safe, excellent clinical, and radiographic outcomes.


Asunto(s)
Fracturas por Compresión , Cifoplastia , Cifosis , Fracturas Osteoporóticas , Escoliosis , Fracturas de la Columna Vertebral , Masculino , Humanos , Femenino , Anciano , Anciano de 80 o más Años , Cifoplastia/métodos , Fracturas por Compresión/diagnóstico por imagen , Fracturas por Compresión/etiología , Fracturas por Compresión/cirugía , Escoliosis/complicaciones , Escoliosis/diagnóstico por imagen , Estudios Retrospectivos , Fracturas de la Columna Vertebral/complicaciones , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/cirugía , Resultado del Tratamiento , Columna Vertebral , Cementos para Huesos/uso terapéutico , Punciones , Cifosis/diagnóstico por imagen , Cifosis/etiología , Cifosis/cirugía , Fracturas Osteoporóticas/complicaciones , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/cirugía
5.
J Oral Rehabil ; 51(9): 1675-1683, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38926933

RESUMEN

BACKGROUND: The T-scan system has been used previously to analyse occlusion, but the quantitative analysis of occlusal contact by T-Scan system has yet to be reported. OBJECTIVES: To evaluate the reliability and validity of T-Scan system for quantitatively measuring occlusal contact area and occlusal contact number. METHODS: Twenty-two individuals with normal occlusion, 11 men and 11 women, were recruited for the study. Two occlusal analysis methods, including silicone transmission analysis method (STA) and T-Scan occlusion analysis method (TSO), were used to make quantitative analysis to measure occlusal contact area (OCA) and occlusal contact number (OCN). A test-retest check was performed with an interval of 2 weeks. The values of intraclass correlation coefficients (ICC) between test-retest of each method were calculated for reliability evaluation. Pearson correlations analysis, paired t-tests, regression analysis and Bland-Altman analysis were performed for validity evaluation. RESULTS: The ICC values of STA were greater than those of TSO for OCA while for OCN, ICC values of TSO were greater than STA. The higher OCA and OCN values were found in TSO compared with STA. Pearson's correlation coefficient indicated strong relations between TSO and STA (0.730-0.812) for OCA, while good relations between then (0.569-0.583) for OCN. Paired t-test showed a significant difference between the OCA and OCN values between TSO and STA. Bland-Altman analysis showed good agreement between OCA and OCN values of TSO and STA both in men and women. Regression analysis identified a linear correlation between OCA values obtained from these two methods. CONCLUSIONS: T-Scan method showed strong reliability for measuring OCA and OCN quantitatively. Strong correlations were found between OCA values from TSO and STA method, but the validity of TSO for measuring OCN needs to be promoted. CLINICAL SIGNIFICANCE: T-Scan system demonstrates good potential in quantitative analysis of occlusion, which will expand its clinical application.


Asunto(s)
Oclusión Dental , Humanos , Femenino , Masculino , Reproducibilidad de los Resultados , Adulto , Adulto Joven , Registro de la Relación Maxilomandibular/métodos , Registro de la Relación Maxilomandibular/instrumentación
6.
Int J Mol Sci ; 25(14)2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39062966

RESUMEN

Membrane-based pervaporation (PV) for organic solvent dehydration is of great significance in the chemical and petrochemical industries. In this work, high-aluminum ZSM-5 zeolite membranes were synthesized by a fluoride-assisted secondary growth on α-alumina tubular supports using mordenite framework inverted (MFI) nanoseeds (~110 nm) and a template-free synthesis solution with a low Si/Al ratio of 10. Characterization by XRD, EDX, and SEM revealed that the prepared membrane was a pure-phase ZSM-5 zeolite membrane with a Si/Al ratio of 3.8 and a thickness of 2.8 µm. Subsequently, two categories of PV performance parameters (i.e., flux versus separation factor and permeance versus selectivity) were used to systematically examine the effects of operating conditions on the PV dehydration performance of different organic solvents (methanol, ethanol, n-propanol, and isopropanol), and their PV mechanisms were explored. Employing permeance and selectivity effectively disentangles the influence of operating conditions on PV performance, thereby elucidating the inherent contribution of membranes to separation performance. The results show that the mass transfer during PV dehydration of organic solvents was mainly dominated by the adsorption-diffusion mechanism. Furthermore, the diffusion of highly polar water and methanol molecules within membrane pores had a strong mutual slowing-down effect, resulting in significantly lower permeance than other binary systems. However, the mass transfer process for water/low-polar organic solvent (ethanol, n-propanol, and isopropanol) mixtures was mainly controlled by competitive adsorption caused by affinity differences. In addition, the high-aluminum ZSM-5 zeolite membrane exhibited superior PV dehydration performance for water/isopropanol mixtures.


Asunto(s)
Membranas Artificiales , Solventes , Zeolitas , Zeolitas/química , Solventes/química , Agua/química , 2-Propanol/química , Aluminio/química , Etanol/química
7.
Anal Chem ; 95(19): 7416-7421, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37138452

RESUMEN

Usually, different assays and instrumentation are required for different types of targets, e.g., nucleic acids, proteins, small molecules, etc., because of significant differences in their structures and sizes. To increase efficiency and reduce costs, a desirable solution is to develop a versatile platform suitable for diverse objectives. Here, we established a versatile detection technique: first, target separation and enrichment were carried out using magnetic beads (MBs); then, different targets were converted to same barcoded DNA strands (BDs) released from gold nanoparticles; finally, sensitive detection of three different targets (miRNA-21, digoxigenin antibody, and aflatoxin B1) was achieved through exonuclease III (Exo III) cyclic cleavage-assisted signal amplification. To simplify the operation, we integrated this technique into a microfluidic chip with multiple chambers in which the requisite reagents were prestored. Just by moving the MBs through different chambers with a magnet, multiple steps can be completed. Due to the limited space in microfluidic chips, the full mixing of MBs and solution is a key point to improve reaction efficiency. The mixing can be achieved by acoustic vibration generated by a small, portable sonic toothbrush. Based on the microfluidic chip, the detection limits of the above three targets were 0.76 pM, 0.16 ng/mL, and 0.56 nM, respectively. Furthermore, miRNA-21 and Digoxigenin antibody (Dig-Ab) in serum and AFB1 in corn powder were also used to demonstrate the performance of this chip. Our versatile platform is easy to operate and is expected to develop into an automatic "sample-to-answer" device.


Asunto(s)
Nanopartículas del Metal , MicroARNs , Técnicas Analíticas Microfluídicas , Microfluídica , Oro/química , Digoxigenina , Nanopartículas del Metal/química , Anticuerpos
8.
Environ Sci Technol ; 57(25): 9174-9183, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-37311089

RESUMEN

Plastic film mulching and urea nitrogen fertilization are widely used in agricultural ecosystems, but both their long-term use may leave a negative legacy on crop growth, due to deleterious effects of plastic and microplastic accumulation and acidification in soil, respectively. Here, we stopped covering soil with a plastic film in an experimental site that was previously covered for 33 years and compared soil properties and subsequent maize growth and yield between plots that were previously and never covered with the plastic film. Soil moisture was about 5-16% higher at the previously mulched plot than at the never-mulched plot, but NO3- content was lower for the former when with fertilization. Maize growth and yield were generally similar between previously and never-mulched plots. Maize had an earlier dough stage (6-10 days) in previously mulched compared to never-mulched plots. Although plastic film mulching did add substantial amounts of film residues and microplastic accumulation into soils, it did not leave a net negative legacy (given the positive effects of the mulching practice in the first place) for soil quality and subsequent maize growth and yield, at least as an initial effect in our experiment. Long-term urea fertilization resulted in a pH decrease of about 1 unit, which bring a temporary maize P deficiency occurring in early stages of growth. Our data add long-term information on this important form of plastic pollution in agricultural systems.


Asunto(s)
Plásticos , Suelo , Suelo/química , Zea mays , Nitrógeno/análisis , Microplásticos , Ecosistema , Agua , Agricultura , Urea , Fertilización , China
9.
Sleep Breath ; 27(6): 2379-2388, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37278870

RESUMEN

PURPOSE: The diagnosis of obstructive sleep apnea (OSA) relies on time-consuming and complicated procedures which are not always readily available and may delay diagnosis. With the widespread use of artificial intelligence, we presumed that the combination of simple clinical information and imaging recognition based on facial photos may be a useful tool to screen for OSA. METHODS: We recruited consecutive subjects suspected of OSA who had received sleep examination and photographing. Sixty-eight points from 2-dimensional facial photos were labelled by automated identification. An optimized model with facial features and basic clinical information was established and tenfold cross-validation was performed. Area under the receiver operating characteristic curve (AUC) indicated the model's performance using sleep monitoring as the reference standard. RESULTS: A total of 653 subjects (77.2% males, 55.3% OSA) were analyzed. CATBOOST was the most suitable algorithm for OSA classification with a sensitivity, specificity, accuracy, and AUC of 0.75, 0.66, 0.71, and 0.76 respectively (P < 0.05), which was better than STOP-Bang questionnaire, NoSAS scores, and Epworth scale. Witnessed apnea by sleep partner was the most powerful variable, followed by body mass index, neck circumference, facial parameters, and hypertension. The model's performance became more robust with a sensitivity of 0.94, for patients with frequent supine sleep apnea. CONCLUSION: The findings suggest that craniofacial features extracted from 2-dimensional frontal photos, especially in the mandibular segment, have the potential to become predictors of OSA in the Chinese population. Machine learning-derived automatic recognition may facilitate the self-help screening for OSA in a quick, radiation-free, and repeatable manner.


Asunto(s)
Inteligencia Artificial , Apnea Obstructiva del Sueño , Masculino , Humanos , Femenino , Reconocimiento Facial Automatizado , Polisomnografía/métodos , Encuestas y Cuestionarios , Aprendizaje Automático , Tamizaje Masivo
10.
Clin Oral Investig ; 27(11): 6813-6821, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37796336

RESUMEN

OBJECTIVES: The objectives of this study included using the cone beam computed tomography (CBCT) technology to assess: (1) intra- and inter-observer reliability of the volume measurement of the nasal cavity; (2) the accuracy of the segmentation protocol for evaluation of the nasal cavity. MATERIALS AND METHODS: This study used test-retest reliability and accuracy methods within two different population sample groups, from Eastern Asia and North America. Thirty obstructive sleep apnea (OSA) patients were randomly selected from administrative and research oral health data archived at two dental faculties in China and Canada. To assess the reliability of the protocol, two observers performed nasal cavity volume measurement twice with a 10-day interval, using Amira software (v4.1, Visage Imaging Inc., Carlsbad, CA). The accuracy study used a computerized tomography (CT) scan of an OSA patient, who was not included in the study sample, to fabricate an anthropomorphic phantom of the nasal cavity volume with known dimensions (18.9 ml, gold standard). This phantom was scanned using one NewTom 5G (QR systems, Verona, Italy) CBCT scanner. The nasal cavity was segmented based on CBCT images and converted into standard tessellation language (STL) models. The volume of the nasal cavity was measured on the acquired STL models (18.99 ± 0.066 ml). RESULTS: The intra-observer and inter-observer intraclass correlation coefficients for the volume measurement of the nasal cavity were 0.980-0.997 and 0.948-0.992 consecutively. The nasal cavity volume measurement was overestimated by 1.1%-3.1%, compared to the gold standard. CONCLUSIONS: The semi-automatic segmentation protocol of the nasal cavity in patients with sleep apnea and by using cone beam computed tomography is reliable and accurate. CLINICAL RELEVANCE: This study provides a reliable and accurate protocol for segmentation of nasal cavity, which will facilitate the clinician to analyze the images within nasoethmoidal region.


Asunto(s)
Síndromes de la Apnea del Sueño , Apnea Obstructiva del Sueño , Humanos , Reproducibilidad de los Resultados , Cavidad Nasal , Tomografía Computarizada de Haz Cónico/métodos , Imagenología Tridimensional/métodos
11.
BMC Oral Health ; 23(1): 190, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-37005643

RESUMEN

BACKGROUND: Occlusal analysis is essential in the dental clinical practice. However, the traditional occlusal analysis performed on the two-dimensional level can not directly correspond to the tooth surface with three-dimensional profile, therefore the clinical guidance value is limited. METHODS: By combining the 3D digital dental models and quantitative data from 2D occlusal contact analysis, this study constructed a novel digital occlusal analysis method. The validity and reliability of DP and SA were verified by comparing the results of occlusal analysis of 22 participants. ICC values for occlusal contact area (OCA) and occlusal contact number (OCN) were tested. RESULTS: Results confirmed the reliability of the two occlusal analysis methods with ICC values of 0.909 for SAOCA, 0.906 for DPOCA, 0.929 for SAOCN and 0.904 for DPOCN. The Bland-Altman plot, paired t-test (tOCN = 0.691, P > 0.05) and Pearson correlation analysis results (R = 0.68, p < 0.001) verified the validity between SA and DP. Then a novel digital occlusal analysis method was constructed, which not only can locate the occlusion contact and provide the quantitative analysis, but also provide a comprehensive description of the resultant force of each tooth and the component forces on the x-, y- and z-axis. CONCLUSIONS: This new occlusal analysis method can obtain quantitative analysis of occlusal contact including contact area and force information simultaneously, which will provide new impetus and greater help for clinical dental treatment and scientific research.


Asunto(s)
Oclusión Dental , Imagenología Tridimensional , Humanos , Reproducibilidad de los Resultados , Modelos Dentales
12.
Intervirology ; 2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36103866

RESUMEN

The novel coronavirus (COVID-19 or 2019-nCoV) is a respiratory virus that can exist in the mouth and saliva of patients and spreads through aerosol dispersion. Therefore, stomatological hospitals and departments have become high-infection-risk environments. Accordingly, oral disinfectants that can effectively inactivate the virus have become a highly active area of research. Hexadecyl pyridinium chloride, povidone-iodine, and other common oral disinfectants are the natural primary choices for stomatological hospitals. Therefore, this study investigated the inhibitory effect of hexadecyl pyridinium chloride on SARS-CoV-2 in vitro. Vero cells infected with SARS-CoV-2 were used to determine the disinfection effect; the CCK-8 method was used to determine cytotoxicity, and viral load was determined by real-time PCR. The results showed that hexadecyl pyridinium chloride has no obvious cytotoxic effect on Vero cells in the concentration range 0.0125-0.05 mg/mL. The in vitro experiments showed that hexadecyl pyridinium chloride significantly inhibits the virus at concentrations of 0.1 mg/mL or above at 2 min of action. Thus, the results provide experimental support for the use of hexadecyl pyridinium chloride in stomatological hospitals.

13.
Environ Sci Technol ; 56(22): 15805-15817, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36282942

RESUMEN

The question of whether long-term chronic exposure to microplastics (MPs) could induce dose- and size-dependent adverse effects in mammals remains controversial and poorly understood. Our study explored potential health risks from dietary exposure to environmentally relevant doses of polystyrene (PS) MPs, through a mouse model and integrated analyses of the interruptions of fecal microbial metagenomes and plasma lipidomes. After 21 weeks of exposure to the MPs (40-100 µm), mice mainly exhibited gut microbiota dysbiosis, tissue inflammation, and plasma lipid metabolism disorder, although no notable accumulation of MPs was observed in the gut or liver. The change of the relative abundance of microbiota was strongly associated with the exposure dose and size of MPs while less significant effects were observed in gut damage and abnormal lipid metabolism. Moreover, multiomics data suggested that the host abnormal lipid metabolism was closely related to bowel function disruptions, including gut microbiota dysbiosis, increased gut permeability, and inflammation induced by MPs. We revealed for the first time that even without notable accumulation in mouse tissues, long-term exposure to MPs at environmentally relevant doses could still induce widespread health risks. This raises concern on the health risks from the exposure of humans and other mammals to environmentally relevant dose MPs.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Humanos , Ratones , Animales , Microplásticos/toxicidad , Poliestirenos/toxicidad , Plásticos/toxicidad , Disbiosis/inducido químicamente , Homeostasis , Inflamación/inducido químicamente , Lípidos , Contaminantes Químicos del Agua/toxicidad , Mamíferos/metabolismo
14.
J Mater Sci Mater Med ; 33(6): 52, 2022 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35657438

RESUMEN

Under whole body vibration, how the cement augmentation affects the vibration characteristic of the osteoporotic fusion lumbar spine, complications, and fusion outcomes is unclear. A L1-L5 lumbar spine finite element model was developed to simulate a transforaminal lumbar interbody fusion (TLIF) model with bilateral pedicle screws at L4-L5 level, a polymethylmethacrylate (PMMA) cement-augmented TLIF model (TLIF-PMMA) and an osteoporotic TLIF model. A 40 N sinusoidal vertical load at 5 Hz and a 400 N preload were utilized to simulate a vertical vibration of the human body and the physiological compression caused by muscle contraction and the weight of human body. The results showed that PMMA cement augmentation may produce a stiffer pedicle screw/rod construct and decrease the risk of adjacent segment disease, subsidence, and rod failure under whole-body vibration(WBV). Cement augmentation might restore the disc height and segmental lordosis and decrease the risk of poor outcomes, but it might also increase the risk of cage failure and prolong the period of lumbar fusion under WBV. The findings may provide new insights for performing lumbar interbody fusion in patients affected by osteoporosis of the lumbar spine. Graphical abstract.


Asunto(s)
Vértebras Lumbares , Fusión Vertebral , Fenómenos Biomecánicos , Análisis de Elementos Finitos , Humanos , Vértebras Lumbares/cirugía , Polimetil Metacrilato , Fusión Vertebral/métodos , Vibración/uso terapéutico
15.
Ecotoxicol Environ Saf ; 245: 114105, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-36155338

RESUMEN

Microplastics (MPs) pollution becomes an increasing concern and researchers keep exploring the health effects caused by MPs exposure. The ageing process in the environment significantly alters the physicochemical characteristics of MPs and subsequently affects their toxicities. The health effects of aged MPs exposure and the mechanism underlying are worthy of exploration. Polystyrene microplastics (PS-MPs) (with size less than 50 µm) were obtained by grinding and screening polystyrene materials. PS-MPs continued to be aged by ozone treatment (0.4 mg/min, 9 h). Both male and female C57BL/6 mice were orally exposed to 0 or 2 mg/kg/d aged PS-MPs for 28 days. Results showed that PS-MPs were found in liver, ovary and spleen of females and liver, testis and spleen of males in the aged PS-MPs group. Exposure to aged PS-MPs significantly decreased abdominal fat/body coefficient, the adipocyte size and the serum LDL-C level in females. Compared to the control, serum estradiol (E2) level, the mRNA expression levels of genes regulating E2 production (17ß-hsd, 3ß-hsd and Star) in ovary and the protein expression levels of E2 receptors (ERα, ERß), AMPKα and p-AMPKα1 in liver increased significantly, and the mRNA expression levels of AMP-activated protein kinase (AMPK) downstream genes (Srebp-1c, Fas and Scd1) in liver decreased significantly in the female aged PS-MPs group. Liver metabolomic profiling showed that differential metabolites between female aged PS-MPs group and female control group were enriched in biotin metabolism and the level of biotin increased significantly in the female aged PS-MPs group. However, no significant changes were detected in males. These results indicated that aged PS-MPs exposure increased ovarian E2 production and activated the AMPK pathway in the liver which might inhibit liver lipid synthesis only in females. Our findings provide new insights into the potential sex-specific health effects of environmental MPs pollution.


Asunto(s)
Microplásticos , Ozono , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Biotina , LDL-Colesterol/metabolismo , Estradiol/metabolismo , Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/metabolismo , Femenino , Metabolismo de los Lípidos , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Microplásticos/toxicidad , Ozono/metabolismo , Plásticos/metabolismo , Poliestirenos/metabolismo , Poliestirenos/toxicidad , ARN Mensajero/metabolismo , Factores Sexuales , Proteína 1 de Unión a los Elementos Reguladores de Esteroles
16.
Ecotoxicol Environ Saf ; 245: 114114, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-36179446

RESUMEN

Previous studies have shown that nanoplastics (NPs) are harmful pollutants that threaten aquatic organisms and ecosystems, however, less research has been conducted on the hazards of NPs for aquaculture animals. In this study, Cherax quadricarinatus was used as an experimental model to evaluate the possible effects of three concentrations (25, 250 and 2500 µg/L) of NPs on red crayfish. The toxicological effects of NPs on this species were investigated based on transcriptomics and microbiome. A total of 67,668 genes were obtained from the transcriptome. The annotation rate of the four major libraries (Nr, KEGG, KOG, Swissprot) was 40.17 %, and the functions of differential genes were mainly related to antioxidant activity, metabolism and immune processes. During the experiment, the activities of superoxide dismutase (SOD) and catalase (CAT) in the high concentration group were significantly decreased, while the concentration of malondialdehyde (MDA) increased after nanoplastics (NPs) exposure, and SOD1, Jafrac1 were significantly reduced at high concentrations. expression is inhibited. The immune genes LYZ and PPO2 were highly expressed at low concentrations and suppressed at high concentrations. After 14 days of exposure to NPs, significant changes in gut microbiota were observed, such as decreased abundances of Actinobacteria, Bacteroidetes, and Firmicutes. NPs compromise host health by inducing changes in microbial communities and the production of beneficial bacterial metabolites. Overall, these results suggest that NPs affect immune-related gene expression and antioxidant enzyme activity in red crayfish and cause redox imbalance in the body, altering the composition and diversity of the gut microbiota.


Asunto(s)
Astacoidea , Contaminantes Ambientales , Animales , Antioxidantes/farmacología , Astacoidea/genética , Catalasa/genética , Ecosistema , Contaminantes Ambientales/farmacología , Secuenciación de Nucleótidos de Alto Rendimiento , Malondialdehído/farmacología , Microplásticos , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa-1
17.
Acta Odontol Scand ; 80(7): 535-546, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35723029

RESUMEN

OBJECTIVE: Periodontitis is a progressive and inflammatory oral disease and results in the damage of the supporting tissues of teeth. Peroxiredoxin 6 (PRDX6) is an antioxidant enzyme identified as a regulator in ferroptosis. This study aimed to investigate whether PRDX6 could protect human gingival fibroblasts (HGFs) from lipopolysaccharide (LPS)-induced inflammation and its mechanisms. MATERIAL AND METHODS: Both inflamed and non-inflamed human gingival tissues were collected to assess the expression of PRDX6 and nuclear factor erythropoietin 2-related factor 2 (NRF2) by Immunohistochemistry and Western blotting. Furthermore, the molecular mechanisms of PRDX6 have been clarified in PRDX6 silenced cells. The inflammatory cytokines in HGFs were measured by RT-qPCR and ELISA. The lipid hydroperoxide (LOOH) was detected by C11-BODIPY. RESULTS: The expression of PRDX6 and NRF2 were decreased in gingival tissues of severe periodontitis patients. The increased LPS-induced LOOH and inflammatory cytokines were found in PRDX6 knockdown HGFs. Besides, the inhibition of ferroptosis or PRDX6 phospholipase A2 activity (PLA2) alleviated LPS-induced inflammatory cytokines and LOOH. However, inhibiting NRF2 signalling upregulated those in HGFs. CONCLUSIONS: Therefore, this study provided a new mechanistic insight that PRDX6, regulated by the NRF2 signalling, alleviates LPS-induced inflammation and ferroptosis in human gingival fibroblasts.


Asunto(s)
Ferroptosis , Periodontitis , Peroxiredoxina VI , Antioxidantes , Citocinas/metabolismo , Ferroptosis/genética , Fibroblastos , Encía/metabolismo , Humanos , Inflamación/genética , Inflamación/metabolismo , Peróxidos Lipídicos/metabolismo , Lipopolisacáridos , Factor 2 Relacionado con NF-E2/metabolismo , Periodontitis/genética , Periodontitis/metabolismo , Peroxiredoxina VI/genética , Peroxiredoxina VI/metabolismo
18.
Molecules ; 27(18)2022 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-36144817

RESUMEN

In this work, novel selective recognition materials, namely magnetic molecularly imprinted polymers (MMIPs), were prepared. The recognition materials were used as pretreatment materials for magnetic molecularly imprinted solid-phase extraction (MSPE) to achieve the efficient adsorption, selective recognition, and rapid magnetic separation of methotrexate (MTX) in the patients' plasma. This method was combined with high-performance liquid chromatography-ultraviolet detection (HPLC-UV) to achieve accurate and rapid detection of the plasma MTX concentration, providing a new method for the clinical detection and monitoring of the MTX concentration. The MMIPs for the selective adsorption of MTX were prepared by the sol-gel method. The materials were characterized by transmission electron microscopy, Fourier transform-infrared spectrometry, X-ray diffractometry, and X-ray photoelectron spectrometry. The MTX adsorption properties of the MMIPs were evaluated using static, dynamic, and selective adsorption experiments. On this basis, the extraction conditions were optimized systematically. The adsorption capacity of MMIPs for MTX was 39.56 mgg-1, the imprinting factor was 9.40, and the adsorption equilibrium time was 60 min. The optimal extraction conditions were as follows: the amount of MMIP was 100 mg, the loading time was 120 min, the leachate was 8:2 (v/v) water-methanol, the eluent was 4:1 (v/v) methanol-acetic acid, and the elution time was 60 min. MTX was linear in the range of 0.00005-0.25 mg mL-1, and the detection limit was 12.51 ng mL-1. The accuracy of the MSPE-HPLC-UV method for MTX detection was excellent, and the result was consistent with that of a drug concentration analyzer.


Asunto(s)
Impresión Molecular , Adsorción , Cromatografía Líquida de Alta Presión , Humanos , Fenómenos Magnéticos , Metanol , Metotrexato , Impresión Molecular/métodos , Polímeros Impresos Molecularmente , Polímeros/química , Extracción en Fase Sólida/métodos , Agua
19.
Mol Pharm ; 18(3): 1196-1207, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33448219

RESUMEN

For active targeting nanodrug delivery systems conjugated with antibodies, both lack of control of the antibody at the molecular level and protein corona formation remarkably decreases targeting efficacy. Herein, we designed a series of silica nanoparticles toward HER2-positive breast cancer cells, with an anti-HER2 Fab-6His density ranging from 50 to 180 molecules per nanoparticle. Through the site-directed immobilization method we developed, the antigen-binding domain of anti-HER2 Fab was mostly accessible to the HER2 receptor. Both polyethylene glycol (PEG) chains and a high density of Fab were shown to suppress protein corona formation and macrophage uptake. The dependency of targeting efficacy and cytotoxicity on Fab density was shown using a series of breast cancer cell lines with different levels of the HER2 expression. The high density of Fab stimulates quick responses from HER2-positive cells. Combined with PEG chains, conjugated antibodies with a well-controlled orientation and density significantly improves delivery performance and sheds light on the design and preparation of an improved active targeting nanodrug delivery system.


Asunto(s)
Anticuerpos/química , Anticuerpos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Nanopartículas/química , Receptor ErbB-2/metabolismo , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Femenino , Humanos , Inmunoconjugados/química , Fragmentos Fab de Inmunoglobulinas/química , Células MCF-7 , Polietilenglicoles/química , Dióxido de Silicio/química , Células THP-1
20.
Ecotoxicol Environ Saf ; 209: 111794, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33348256

RESUMEN

Microplastics (MPs) in the form of microfibres (MFs) are of great concern because of their size and increasing abundance, which increase their potential to interact with or be ingested by aquatic organisms. Although MFs are the dominant shape of MPs ingested by sea cucumbers in habitats, their effect on sea cucumbers remains unclear. This study examined the effect of dietary exposure to MFs on the growth and physiological status of both juvenile and adult Apostichopus japonicus sea cucumbers. MFs were mixed into the diet of sea cucumbers for 60 d at environmentally relevant concentrations of 0.6 MFs g-1, 1.2 MFs g-1 and 10 MFs g-1. Dietary exposure to MFs, with concentrations at or above those commonly found in the habitats, did not significantly affect the growth and faecal production rate of either juvenile or adult sea cucumbers. However, a disruption in immunity indices (acid phosphatase and alkaline phosphatase activity) and oxidative stress indices (total antioxidant capacity and malondialdehyde content) was observed in juvenile and adult sea cucumbers, indicating that these indices might be useful as potential biomarkers of the exposure to MF ingestion in sea cucumbers. This study provides insights into the toxicity mechanism of MF ingestion in a commercially and ecologically important species.


Asunto(s)
Microplásticos/toxicidad , Pepinos de Mar/fisiología , Pruebas de Toxicidad Crónica , Contaminantes Químicos del Agua/toxicidad , Animales , Antioxidantes , Dieta , Ingestión de Alimentos , Inmunidad Innata , Malondialdehído , Plásticos , Stichopus/crecimiento & desarrollo
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