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1.
Artículo en Inglés | MEDLINE | ID: mdl-38538873

RESUMEN

Endo-1,4-ß-xylanase is a key xylanolytic enzyme, and our study aimed to enhance the catalytic properties of Alteromones Macleadii xylanase (Xyn ZT-2) through sequence-guided design approach. Analysis of the amino acid sequence revealed highly conserved residues near the active site, with few differences. Introducing various mutations allowed us to modify the enzyme's catalytic performance. Particularly, the A152G mutation led to a 9.8-fold increase in activity and a 23.2-fold increase in catalytic efficiency. Moreover, A152G exhibited an optimal temperature of 65 °C, 20 °C higher than that of Xyn ZT-2, while the T287S mutant showed a 4.9-fold increase in half-life. These results underscore the role of amino acid evolution in shaping xylanase catalysis. Through targeted sequence analysis and a focused mutation library, we effectively improved catalytic performance, providing a straightforward approach for enhancing enzyme efficiency.

2.
Sensors (Basel) ; 24(4)2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38400348

RESUMEN

Machine learning (ML) algorithms are increasingly applied to structure health monitoring (SHM) problems. However, their application to pile damage detection (PDD) is hindered by the complexity of the problem. A novel multi-sensor pile damage detection (MSPDD) method is proposed in this paper to extend the application of ML algorithms in the automatic identification of PDD. The time-series signals collected by multiple sensors during the pile integrity test are first processed by the traveling wave decomposition (TWD) theory and are then input into a hybrid one-dimensional (1D) convolutional and recurrent neural network. The hybrid neural network can achieve the automatic multi-task identification of pile damage detection based on the time series of MSPDD results. Finally, the analytical solution-based sample set is utilized to evaluate the performance of the proposed hybrid model. The outputs of the multi-task learning framework can provide a detailed description of the actual pile quality and provide strong support for the classification of pile quality as well.

3.
Int Arch Allergy Immunol ; 185(2): 182-189, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37980884

RESUMEN

INTRODUCTION: Comorbidities, such as gastroesophageal reflux disease (GERD), are common in patients with rhinosinusitis (RS). However, the link between RS and GERD has not been fully understood. This study aimed to investigate the causal relationship between GERD and acute (ARS) or chronic RS (CRS), providing references for the pathogenesis and management of RS. METHODS: The data were obtained from the Integrative Epidemiology Unit Open GWAS project and FinnGen. A total of 972,838 individuals were included. The inverse variance-weighted (IVW) method was applied to obtain the primary results of the study. Weighted median, MR-Egger, and mode-based methods were used to determine the robustness of the results. Cochran's Q statistic and MR-Egger method were applied to detect heterogeneity and pleiotrophy in instrumental variables (IVs). Other sensitivity analyses included MR-PRESSO and leave-one-out analysis. RESULTS: The MR study showed that GERD was associated with an increased risk of CRS (OR: 1.36, 95% CI: 1.18-1.57, p < 0.001). The results of other analysis methods were broadly consistent with the IVW estimate. No heterogeneity was detected by Cochran's Q test (p = 0.061) and MR-PRESSO (p = 0.074). No horizontal pleiotropy was shown in IVs (p = 0.700). GERD was also associated with an increased risk of ARS (OR: 1.31, 95% CI: 1.17-1.48, p < 0.001). Some analytical results were inconsistent with the IVW estimate. No heterogeneity and pleiotropy were observed. There was no sufficient evidence for a reverse causal effect of RS on GERD. CONCLUSION: Our study supported that GERD promoted the risk of CRS and may be a potential risk factor for ARS. This provides additional support for further investigation into the mechanisms of GERD on RS.


Asunto(s)
Reflujo Gastroesofágico , Rinosinusitis , Humanos , Análisis de la Aleatorización Mendeliana , Reflujo Gastroesofágico/complicaciones , Reflujo Gastroesofágico/epidemiología , Factores de Riesgo , Estudio de Asociación del Genoma Completo
4.
Sensors (Basel) ; 23(19)2023 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-37837138

RESUMEN

The in-hole multipoint traveling wave decomposition (MPTWD) method is developed for detecting and characterizing the damage of cast in situ reinforced concrete (RC) piles. Compared with the results of MPTWD, the results of the in-hole MPTWD reconstruction technique are found ideal for evaluating the lower-part pile integrity and are further utilized to establish a data-driven machine-learning framework to detect and quantify the degree of damage. Considering the relatively small number of field test samples of the in-hole MPTWD method at this stage, an analytical solution is employed to generate sufficient samples to verify the feasibility and optimize the performance of the machine learning modeling framework. Two types of features extracted by the distributed sampling and statistical and signal processing techniques are applied to three machine-learning classifiers, i.e., logistic regression (LR), extreme gradient boosting (XGBoost) and multilayer perceptron (MLP). The performance of the data-driven machine-learning framework is then evaluated through a specific case study. The results demonstrate that all three classifiers perform better when employing the statistical and signal processing techniques, and the total of 24 extracted features are sufficient for the machine-learning algorithms.

5.
Polymers (Basel) ; 15(17)2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37688169

RESUMEN

As one of the most successful modified phenolic resins, boron-modified phenolic resin (BPF) has excellent heat resistance and ablative resistance, good mechanical and wear resistance, and flame retardancy. BPF and its composites can be widely used in areas such as aerospace, weapons and equipment, automobile brakes, and fire retardants. In this review, the current state of development of BPF and its composites is presented and discussed. After introducing various methods to synthesize BPF, functionalization of BPF is briefly summarized. Particular emphasis is placed on general methods used to fabricate BPF-based composites and the heat resistance, ablative resistance, mechanical property, wear resistance, flame retardancy, and water resistance of BPF-based composites. Finally, the challenges of this research area are summarized and its future outlook is prospected.

6.
Front Plant Sci ; 14: 1187922, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37389300

RESUMEN

It is well documented that high temperature (HT) severely affects the development of soybean male reproductive organs. However, the molecular mechanism of thermo-tolerance in soybean remains unclear. To explore the candidate genes and regulatory mechanism of soybean response to HT stress and flower development, here, the anthers of two previously identified HT-tolerant (JD21) and HT-sensitive (HD14) varieties were analyzed by RNA-seq. In total, 219 (172 upregulated and 47 downregulated), 660 (405 upregulated and 255 downregulated), and 4,854 (2,662 upregulated and 2,192 downregulated) differentially expressed genes (DEGs) were identified between JD21 anthers treated with HT stress vs. JD21 anthers in the natural field conditions (TJA vs. CJA), HD14 anthers treated with HT stress vs. HD14 anthers in the natural field conditions (THA vs. CHA), and JD21 vs. HD14 anthers treated with HT stress (TJA vs. THA), respectively. The results showed that there were more DEGs upregulated in JD21; this might be the reason why JD21 was more HT-resistant than the HT-sensitive variety HD14. GO annotation and KEGG enriched analysis showed that many DEGs are mainly involved in defense response, response to biological stimuli, auxin-activated signaling pathway, plant hormone signal transduction, MAPK signaling pathway-plant, starch and sucrose metabolism, etc. The conjoint analysis of RNA-seq and previous iTRAQ results found that there were 1, 24, and 54 common DEGs/DAPs showing the same expression pattern and 1, 2, and 13 common DEGs/DAPs showing the opposite pattern between TJA vs. CJA, THA vs. CHA, and TJA vs. THA at the protein and gene level, respectively, among which HSPs, transcription factor, GSTU, and other DEGs/DAPs participated in the response to HT stress and flower development. Notably, the qRT-PCR analysis and physiological index change results coincided with the sequencing results of RNA-seq and iTRAQ. In conclusion, the HT-tolerant cultivar performed better under stress than the HT-sensitive cultivar through modulation of HSP family proteins and transcription factors, and by keeping key metabolic pathways such as plant hormone signal transduction normal. This study provided important data and some key candidate genes to better study the effect and molecular basis of HT on anther in soybean at a transcription and translation level.

7.
BMC Plant Biol ; 23(1): 90, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36782110

RESUMEN

BACKGROUND: In seed plants, the ovule is the precursor to the seed. The process of ovule development and differentiation is regulated by multiple factors, including starch metabolism and endogenous hormones. Castanea henryi produces nuts with high nutritional value. However, the high proportion of empty buds restricts the commercial use of the tree. Previous studies have shown that the empty bud phenotype is closely related to ovule abortion. If none of the ovules in the ovary expand rapidly and develop in 7-8 weeks after pollination, an empty bud will form. Therefore, we studied the development and molecular mechanisms underlying single seed formation in C. henryi. RESULTS: We found that 49 days after pollination (DAP) is a critical period for the formation of fertile and abortive ovules. The morphology and starch distribution of the fertile and abortive ovules differed significantly at 49 DAP. The fertile ovules were smooth and round in appearance, with a large amount of starch. In contrast, abortive ovules were smaller with only a small amount of starch. The embryo sac of the abortive ovule proceeded to develop abnormally, and the entire ovule lacked starch. We identified 37 candidate genes involved in metabolism with potential roles in the regulation of starch levels. Three ADP-glucose pyrophosphorylase (AGPase) genes, one granule-bound starch synthase (GBSS) gene, and two beta-amylase genes could affect starch accumulation. The levels of auxin, cytokinins, gibberellins, and jasmonic acid in fertile ovules were higher than those in abortive ovules. In addition, the levels of endogenous abscisic acid and salicylic acid in abortive ovules were higher than those in fertile ovules of the same age, consistent with the expression patterns of genes related to the synthesis of abscisic and salicylic acid and signal transduction. We identified and mapped the differentially expressed genes associated with hormone synthesis and signal transduction. CONCLUSIONS: These results improve our general understanding of the molecular mechanisms underlying single seed development in C. henryi and the phenomenon of empty buds, providing directions for future research.


Asunto(s)
Perfilación de la Expresión Génica , Transcriptoma , Semillas , Almidón/metabolismo , Hormonas/metabolismo , Óvulo Vegetal , Regulación de la Expresión Génica de las Plantas
8.
Int J Nanomedicine ; 18: 455-472, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36718191

RESUMEN

Musculoskeletal disorders are the second leading cause of disability worldwide, posing a huge global burden to the public sanitation system. Currently, tissue engineering-based approaches act as effective strategies, which are, however, challenging in limited application scenarios. Mussel-based biomimetic materials, exhibit numerous unique properties such as intense adhesion, biocompatibility, moisture resistance, and injectability, to name only a few, and have attracted extensive research interest. In particular, featuring state-of-the-art properties, mussel-inspired biomaterials have been widely explored in innumerable musculoskeletal disorder treatments including osteochondral defects, osteosarcoma, osteoarthritis, ligament rupture, and osteoporosis. Nevertheless, a comprehensive and timely discussion of their applications in musculoskeletal disorders is insufficient. In this review, we emphasize on (1) the main categories and characteristics of mussel foot proteins and their fundamental mechanisms for the spectacular adhesion in mussels; (2) the diverse synthetic methods and modification of various polymers; and (3) the emerging applications of mussel-biomimetic materials, the future perspectives, and challenges, especially in the area of musculoskeletal disorder. We envision that this review will provide a unique and insightful perspective to improve the development of a new generation of mussel biomimetic strategies.


Asunto(s)
Materiales Biomiméticos , Bivalvos , Enfermedades Musculoesqueléticas , Animales , Humanos , Biomimética , Materiales Biocompatibles , Materiales Biomiméticos/uso terapéutico , Enfermedades Musculoesqueléticas/terapia
9.
Polymers (Basel) ; 14(22)2022 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-36433030

RESUMEN

Herein, mechanically robust and flexible graphene oxide/polyimide (GO/PI) hybrid aerogels (GIAs) were fabricated by a facile method, in which the mixed suspensions of the water-soluble polyimide precursor and graphene oxide (GO) sheets were freeze-dried, which was followed by a routine thermal imidation process. The porous GIAs obtained not only exhibit excellent elasticity and extremely low density values (from 33.3 to 38.9 mg.cm-3), but they also possess a superior compressive strength (121.7 KPa). The GIAs could support a weight of up to 31,250 times of its own weight, and such a weight-carrying capacity is much higher than that of other typical carbon-based aerogels. Having such a porous structure, and high strength and toughness properties make GIAs ideal candidates for oil spill cleanup materials. The oil/organic solvents' absorption capacity ranges from 14.6 to 85, which is higher than that of most other aerogels (sponges). With their broad temperature tolerance and acidic stability, the unique multifunctional GIAs are expected to further extend their application range into extreme environments.

10.
Front Bioeng Biotechnol ; 10: 1023231, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36406210

RESUMEN

As bone biology develops, it is gradually recognized that bone regeneration is a pathophysiological process that requires the simultaneous participation of multiple systems. With the introduction of osteoimmunology, the interplay between the immune system and the musculoskeletal diseases has been the conceptual framework for a thorough understanding of both systems and the advancement of osteoimmunomodulaty biomaterials. Various therapeutic strategies which include intervention of the surface characteristics or the local delivery systems with the incorporation of bioactive molecules have been applied to create an ideal bone microenvironment for bone tissue regeneration. Our review systematically summarized the current research that is being undertaken in the field of osteoimmunomodulaty bone biomaterials on a case-by-case basis, aiming to inspire more extensive research and promote clinical conversion.

11.
Front Pharmacol ; 13: 842525, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35754493

RESUMEN

Intervertebral disc degeneration (IDD), characterized by conversion of genotypic and phenotypic, is a major etiology of low back pain and disability. In general, this process starts with alteration of metabolic homeostasis leading to ongoing inflammatory process, extracellular matrix degradation and fibrosis, diminished tissue hydration, and impaired structural and mechanical functionality. During the past decades, extensive studies have focused on elucidating the molecular mechanisms of degeneration and shed light on the protective roles of various factors that may have the ability to halt and even reverse the IDD. Mutations of GDF-5 are associated with several human and animal diseases that are characterized by skeletal deformity such as short digits and short limbs. Growth and differentiation factor-5 (GDF-5) has been shown to be a promise biological therapy for IDD. Substantial literature has revealed that GDF-5 can decelerate the progression of IDD on the molecular, cellular, and organ level by altering prolonged imbalance between anabolism and catabolism. GDF family members are the central signaling moleculars in homeostasis of IVD and upregulation of their gene promotes the expression of healthy nucleus pulposus (NP) cell marker genes. In addition, GDF signaling is able to induce mesenchymal stem cells (MSCs) to differentiate into NPCs and mobilize resident cell populations as chemotactic signals. This review will discuss the promising critical role of GDF-5 in maintenance of structure and function of IVDs, and its therapeutic role in IDD endogenous repair.

12.
BMC Cardiovasc Disord ; 22(1): 32, 2022 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-35120453

RESUMEN

BACKGROUND: Aortic diameter is a critical parameter for the diagnosis of aortic dilated diseases. Aortic dilation has some common risk factors with cardiovascular diseases. This study aimed to investigate potential influence of traditional cardiovascular risk factors and the measures of subclinical atherosclerosis on aortic diameter of specific segments among adults. METHODS: Four hundred and eight patients with cardiovascular risk factors were prospectively recruited in the observational study. Comprehensive transthoracic M-mode, 2-dimensional Doppler echocardiographic studies were performed using commercial and clinical diagnostic ultrasonography techniques. The aortic dimensions were assessed at different levels: (1) the annulus, (2) the mid-point of the sinuses of Valsalva, (3) the sinotubular junction, (4) the ascending aorta at the level of its largest diameter, (5) the transverse arch (including proximal arch, mid arch, distal arch), (6) the descending aorta posterior to the left atrium, and (7) the abdominal aorta just distal to the origin of the renal arteries. Multivariable linear regression analysis was used for evaluating aortic diameter-related risk factors, including common cardiovascular risk factors, co-morbidities, subclinical atherosclerosis, lipid profile, and hematological parameters. RESULTS: Significant univariate relations were found between aortic diameter of different levels and most traditional cardiovascular risk factors. Carotid intima-media thickness was significantly correlated with diameter of descending and abdominal aorta. Multivariate linear regression showed potential effects of age, sex, body surface area and some other cardiovascular risk factors on aortic diameter enlargement. Among them, high-density lipoprotein cholesterol had a significantly positive effect on the diameter of ascending and abdominal aorta. Diastolic blood pressure was observed for the positive associations with diameters of five thoracic aortic segments, while systolic blood pressure was only independently related to mid arch diameter. CONCLUSION: Aortic segmental diameters were associated with diastolic blood pressure, high-density lipoprotein cholesterol, atherosclerosis diseases and other traditional cardiovascular risk factors, and some determinants still need to be clarified for a better understanding of aortic dilation diseases.


Asunto(s)
Aorta Abdominal/diagnóstico por imagen , Aorta Torácica/diagnóstico por imagen , Presión Sanguínea/fisiología , Enfermedades Cardiovasculares/diagnóstico , Vigilancia de la Población , Adulto , Anciano , Anciano de 80 o más Años , Aorta Abdominal/fisiopatología , Aorta Torácica/fisiopatología , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/fisiopatología , Ecocardiografía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Estudios Retrospectivos , Ultrasonografía
13.
Biol Trace Elem Res ; 199(2): 513-526, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32557106

RESUMEN

It remains obscure whether circulating aortic zinc (Zn) and copper (Cu) levels are associated with the progress of human abdominal aortic aneurysms (AAA). Therefore, we conducted a meta-analysis to explore this relationship. A literature search on circulating and aortic zinc and copper levels and AAA patients was conducted using online databases including PubMed, Embase, and Cochrane up to March 20, 2019. To compare Zn and Cu concentrations in AAA patients with those in aortic occlusive disease (AOD) patients or healthy aorta donors or healthy blood donors, pooled weighted mean difference (WMD) and its 95% confidence interval (CI) were calculated. Subgroup analysis, sensitivity analysis, and meta-regression analysis were applied to explain the heterogeneity and evaluate the robustness of combined results. A total of 10 cross-sectional studies, including 252 cases and 304 controls, were used for meta-analysis. We found that circulating zinc and Zn/Cu ratio in AAA patients were significantly lower [WMD (95%CI): - 2.23 (- 4.10, - 0.36); - 0.18 (- 0.31, - 0.05), respectively] than those in non-AAA patients. Similarly, aneurysmal aorta had significantly lower zinc levels and Zn/Cu ratio [WMD (95%CI): - 9.22 (- 15.37, - 3.07); - 6.46 (- 10.14, - 2.77), respectively] than those in control group. No difference in circulating or aortic copper levels was noted between AAA patients and control group [WMD (95%CI): - 0.24 (- 2.09, 1.61); 0.30 (- 0.01, 0.61) , respectively]. Our meta-analysis suggests that zinc levels and Zn-Cu ratio, but not copper levels, may influence aneurysmal progress of AAA.


Asunto(s)
Aneurisma de la Aorta Abdominal , Cobre , Aorta , Estudios Transversales , Humanos , Zinc
14.
Appl Opt ; 59(7): 2065-2071, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32225728

RESUMEN

Pyramidal structures, including upright pyramids and inverted pyramids (IPs), are commonly used as light-trapping structures for silicon solar cells and silicon photodetectors. In this paper, the possible ray propagation paths in a pyramidal structure are analyzed by establishing a mathematical model in which up to seven ray paths may exist either in a regular or random pyramidal structure. To reduce the reflectivity, the proportion of the quadruple bounce should be increased because of its lower reflectivity. Therefore, a chain IP structure with a quadruple bounce proportion of 10.33% is proposed, of which the overlap value $\Delta x/w$Δx/w is 0.4. According to theoretical ray-tracing calculations, the weighted average reflectivity is reduced by 0.75% compared to that of a random IP structure. Experimentally, chain IP structures are fabricated from the surface line damage produced by the diamond wire sawing of a silicon wafer as a mask, and the reflectivity of the structures is 0.80% lower than that of a random IP structure. The theoretical analysis and experimental results both show that the chain IP structure has better optical properties than the random IP structure, indicating promising prospects for the abovementioned applications.

15.
J Colloid Interface Sci ; 552: 27-33, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31100688

RESUMEN

Underwater superoleophobic coatings have attracted significant research attention for their excellent oil-repellent properties. However, the major challenge for current coatings is poor performance under harsh conditions, leading to limitations in terms of practical application. In this paper, we present a novel bioinspired poly(vinyl alcohol)/zeolite composite coating that can be fabricated through a facile approach. This composite coating shows outstanding underwater superoleophobicity to various oils, as well as good wax-prevention and self-cleaning performance. Furthermore, the excellent mechanical and chemical stabilities of the coating make it suitable for practical applications in harsh environments. This bioinspired multifunctional composite coating has promising prospects in the petroleum industry.

16.
ACS Appl Mater Interfaces ; 11(12): 11904-11909, 2019 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-30829470

RESUMEN

Particulate matter (PM) pollution is a serious threat to human health. Zeolitic imidazolate framework-8 (ZIF-8) is a kind of metal-organic framework, and ZIF-8 not only can capture PM2.5 efficiently but also possesses excellent chemical and thermal stability. In this study, ZIF-8-modified soluble polyimide (PI) nanofibrous membranes were prepared via an electrospinning process. As a result, the PI-ZIF membrane shows high PM2.5 filtration efficiency (up to 96.6 ± 2.9%), superior thermal stability (up to 300 °C), good transmittance, excellent mechanical properties, and low pressure drop. The prepared PI-ZIF membrane with excellent comprehensive property shows a promising application in PM2.5 capture, especially in harsh conditions.

17.
ACS Appl Mater Interfaces ; 11(10): 10052-10058, 2019 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-30811936

RESUMEN

We reported a novel texture method through one-step Cu/Ag-cocatalyzed chemical etching which can be widely used in the photovoltaic industry because of its simple and low-cost process. The etching mechanism of an inverted rectangular pyramid is the cooperation of Ag-catalyzed vertical etching and Cu-catalyzed lateral etching. In our texture method, neither saw damage removal nor post-treatment is needed. During the etching process, the digging holes by Ag-catalyzed etching and enlarging holes by Cu-catalyzed etching completed at the same step. Benefiting from the excellent light-trapping and passivation effect of the inverted rectangular pyramid, diamond wire sawing multicrystalline silicon (mc-Si) Al-BSF solar cells with a super high efficiency of 19.49% had been obtained.

18.
Sci Rep ; 8(1): 3408, 2018 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-29467511

RESUMEN

The so called inverted pyramid arrays, outperforming conventional upright pyramid textures, have been successfully achieved by one-step Cu assisted chemical etching (CACE) for light reflection minimization in silicon solar cells. Due to the lower reduction potential of Cu2+/Cu and different electronic properties of different Si planes, the etching of Si substrate shows orientation-dependent. Different from the upright pyramid obtained by alkaline solutions, the formation of inverted pyramid results from the coexistence of anisotropic etching and localized etching process. The obtained structure is bounded by Si {111} planes which have the lowest etching rate, no matter what orientation of Si substrate is. The Si etching rate and (100)/(111) etching ratio are quantitatively analyzed. The different behaviors of anisotropic etching of Si by alkaline and Cu based acid etchant have been systematically investigated.

19.
Exp Ther Med ; 14(3): 2235-2240, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28962148

RESUMEN

Chronic inflammation often delays fracture healing or leads to bone nonunion. Effectively suppressing pathological inflammation is crucial for fracture healing or bone remodeling. Triptolide, which is a diterpenoid epoxide, is the major active component of the Thunder God Vine, Tripterygium wilfordii. The aim of the present study was to investigate the role of triptolide in osteoblast differentiation and explore the molecular mechanisms of triptolide in fracture healing. Alkaline phosphatase (ALP) activity was used to evaluate osteoblast differentiation. ALP activity was measured via histochemical staining and western blotting was used to determine the expression of factors associated with inflammation. C2C12 cells were initially treated with 200 ng/ml bone morphogenetic protein (BMP)-2 alone for 3 days, which caused a significant increase in ALP activity (P<0.01). However, treatment with tumor necrosis factor (TNF)-α significantly decreased the ALP activity (P<0.05). Notably, treatment with the chronic inflammatory cytokine TNF-α significantly decreased the effect of BMP-2 in C2C12 cells compared with BMP-2 treatment alone (P<0.01). C2C12 cells were treated with increasing concentrations of BMP-2 or TNF-α for 3 days. The results demonstrated that TNF-α treatment significantly inhibited BMP-2-induced osteoblast differentiation in a dose-dependent manner (P<0.01). The role of triptolide in BMP-2-induced osteoblast differentiation was also examined. Cells were treated with BMP-2, BMP-2 + TNF-α alone, or BMP2 + TNF-α with increasing concentrations of triptolide (4, 8 or 16 ng/ml). After 3 days, the results of ALP activity revealed that triptolide significantly reversed the TNF-α-associated inhibition of osteoblast differentiation (P<0.01). Western blotting analysis demonstrated that triptolide markedly inhibited the phosphorylation of nuclear factor-κB, therefore suppressing the effects of TNF-α. In summary, triptolide is able to reverse the TNF-α-associated suppression of osteoblast differentiation, suggesting that triptolide treatment may have a positive effect on bone remodeling and fracture repairing.

20.
Adv Mater ; 28(25): 5099-105, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27135462

RESUMEN

Ceramic/polymer composite equipped with 3D interlocking skeleton (3D IL) is developed through a simple freeze-casting method, exhibiting exceptionally light weight, high strength, toughness, and shock resistance. Long-range crack energy dissipation enabled by 3D interlocking structure is considered as the primary reinforcing mechanism for such superior properties. The smart composite design strategy should hold a place in developing future structural engineering materials.

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