RESUMO
PURPOSE: To explore and measure the presence and activity of tendon-derived stem cells (TDSCs), as well as histological changes of rotator cuff remnant by age and chronicity of the rotator cuff tear (RCT). METHODS: 154 patients with a full-thickness tear of supraspinatus and/or infraspinatus tendon were included. 52 qualified remnants of the greater tuberosity were captured through arthroscopy. TDSCs in the remnants were isolated for proliferation ability, basal gene expression, and trilineage differentiation detection. Histological characteristics were evaluated by observation of staining under a light microscope and transmission electron microscopy (TEM). To observe the effect of age, samples were divided into two groups: young (ï¼60 years old) and old (≥60 years old). For chronicity comparison, samples were divided into three groups: acute group (ï¼3 months), intermediate group (3-12 months), and chronic group (≥12 months). RESULTS: Between age groups, the remnants in older patients were found to have lower TDSC proliferation ability (cell counting kit-8 results, old: .5325 ± .050, young: .6623 ± .196; P = .008) and basal expression of aggrecan (.630 ± .239; P = .002) and TGF-ß1 (transforming growth factor-ß1, .589 ± .326, P = .008), weaker ability of chondrogenic differentiation. Furthermore, the remnant tendons in chronic group was found to have weaker adipogenic and chondrogenic differentiation ability of TDSCs, lower tendon degenerative score (acute: 3.57 ± 1.902, intermediate: 5.94 ± 2.313, chronic: 6.86 ± 2.193; P = .023), increased type III collagen region ratio in insertion area (acute: 86.10% ± 8.29%, intermediate: 94.06% ± 5.36%, chronic: 98.90% ± .49%; P = .023), and larger fibril diameters. CONCLUSION: Differentiation ability of TDSCs derived from the rotator cuff remnant was reduced with age and chronicity. Histological degeneration of remnant tendon deteriorated with chronicity. Remnant in the greater tuberosity was still alive, but those in young or acute injury patients were more active after full-thickness RCT. CLINICAL RELEVANCE: TDSCs exist in rotator cuff remnant on the greater tuberosity and have multilineage differentiation ability. But the remnant degenerated with age and chronicity.
Assuntos
Lesões do Manguito Rotador , Manguito Rotador , Idoso , Diferenciação Celular , Humanos , Pessoa de Meia-Idade , Manguito Rotador/patologia , Lesões do Manguito Rotador/patologia , Lesões do Manguito Rotador/cirurgia , Células-Tronco , Tendões/patologiaRESUMO
Lipopolysaccharide (LPS)-induced macrophage activation is a prototype of innate immune response. Although key effector proteins in LPS signaling pathway have been revealed, the map of dynamic protein interactions and phosphorylation as well as the stoichiometry of protein complexes are lacking. Here we present a dynamic map of protein interactions and phosphorylation in MyD88, TRAF6 and NEMO complexes obtained by SWATH-MS. The comprehensive MS measurement leads to quantification of up to about 3,000 proteins across about 21-40 IP samples. We detected and quantified almost all known interactors of MyD88, TRAF6 and NEMO. By analyzing these quantitative data, we uncovered differential recruitment of IRAK family proteins to LPS-induced signaling complexes and determined the stoichiometry of the Myddosome complex. In addition, quantitative phosphoproteomics analysis identified a number of unreported high-confidence phosphosites on the key proteins in LPS signaling pathway. Collectively, data of dynamic protein interactions and phosphorylation presented by this study could be a resource for further study of the LPS signaling pathway.
Assuntos
Lipopolissacarídeos/metabolismo , Espectrometria de Massas/métodos , Transdução de Sinais , Animais , Bases de Dados de Proteínas , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Fator 88 de Diferenciação Mieloide/metabolismo , Fosforilação , Ligação Proteica , Células RAW 264.7 , Fator 6 Associado a Receptor de TNF , Receptor 4 Toll-Like/metabolismoRESUMO
PURPOSE: This study seeks to evaluate the biomechanical relationship between the severity of rotator cable tears and the function of the rotator cuff. METHODS: Twelve cadaveric shoulders with intact rotator cuff, existing rotator cable, and a critical shoulder angle below 35° were included. For each shoulder, a posterosuperior rotator cuff tear (PSRCT) (model 2) in the crescent area was formed. Then anterior insertion detached (model 3), anterior insertion detached together with the middle cable tear (model 4), and the whole rotator cable tear (model 5) were subsequently created. The rotator cuff that lay above the humeral head rotation center was detached as a global tear control (model 6), along with the primitive status as the intact control (model 1). Glenohumeral abduction was initiated by simulating deltoid and remaining rotator cuff force. Functioning of the remaining rotator cuff was evaluated using the middle deltoid force (MDF), as required for abduction. RESULTS: No statistically significant differences in peak MDF values were seen among the 4 PSRCT statuses (44.10 ± 7.30 N [model 2], P = .96; 45.50 ± 9.55 N [model 3], P = .86; 45.90 ± 3.53 N [model 4], P = 0.30; 44.20 ± 8.19 N [model 5], P = .80) and intact control status (39.79 ± 7.65 N [model 1]). However, significant differences in peak MDF values were found among the 4 PSRCT statuses and the global tear control status (54.53 ± 7.46 N [model 6], P < .01). CONCLUSION: The PSRCT, regardless of the severity of the rotator cable tear, does not induce functionally significant biomechanical impairment. Tear extension involving all rotator cuff tissue above the geometric rotation center of the humeral head results in obvious functional impairment. CLINICAL RELEVANCE: For PSRCT, the remaining rotator cuff tissue above the geometric rotation center may contribute to the preservation of shoulder function in RCT patients.
Assuntos
Lesões do Manguito Rotador , Articulação do Ombro , Fenômenos Biomecânicos , Cadáver , Humanos , Amplitude de Movimento Articular , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/cirurgiaRESUMO
Laser-induced breakdown spectroscopy (LIBS) has been considered a promising technology for nuclear safeguard inspection, especially for isotope content ratio determination, since it can be easily designed for portable, fast, and in situ measurement. However, it was a challenge to determine hydrogen isotopes in metal samples due to the unfavorable spectral interference, the poor calibration of the hydrogen content, and the small difference between the atomic emission intensity of hydrogen isotopes at around 656.28 nm. This paper presents the determination of hydrogen isotope contents ratio using LIBS under partially baseline-resolved conditions. The results show that by introducing a proper buffer atmosphere for the LIBS measurement, the resolution of the hydrogen and deuterium emissions could be improved, but still not enabled, by a baseline resolution with a moderate resolution spectrometer. However, with the method of integral intensity correction, the accurate quantitative measurement of hydrogen and deuterium contents in a metal matrix could be achieved. This work provided the possibilities for the further development of LIBS in hydrogen isotopes in in situ measurement for nuclear safeguards.
RESUMO
OBJECTIVE: To propose a novel morphological classification method for notches, which may provide new evidence for notchplasty based on the three-dimensional (3D) features of notches and the risk of anterior cruciate ligament (ACL) injury. MATERIALS AND METHODS: Three hundred individuals in total were included in our study, including 150 patients with ACL ruptures (75 males and 75 females) and 150 age- and gender-matched individuals without ACL ruptures. The notches were divided into four types according to the notch widths at the notch inlet, outlet, and ACL attachment based on the preoperative MRI, the notch volume was calculated, and the risk of ACL injury was compared. The surgical records were reviewed and whether these cases performed notchplasty were collected. RESULTS: The inlet-and-outlet stenosis notch type was associated with smaller notch volume (P = 0.007) and a higher risk of ACL injury (P < 0.001). There were no significant differences in morphological distribution between males and females. The rate of notchplasty in inlet-and-outlet stenosis type was higher than the others. CONCLUSIONS: The new morphological classification method efficiently reflected the association of the notch shape with the 3D notch volume and the risk of ACL injury. The knees with the inlet-and-outlet stenosis notch type and smaller notch volume tended to have a higher risk of ACL injury. Level of evidence Level III, case-control study.
Assuntos
Lesões do Ligamento Cruzado Anterior/diagnóstico por imagem , Constrição Patológica/classificação , Fêmur/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Adolescente , Adulto , Constrição Patológica/diagnóstico por imagem , Feminino , Fêmur/anormalidades , Fêmur/anatomia & histologia , Humanos , Imageamento Tridimensional , Articulação do Joelho/anatomia & histologia , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos , Fatores de Risco , Adulto JovemRESUMO
BACKGROUND AND AIMS: Crohn's disease (CD) is a chronic, complex inflammatory condition with increasing incidence and prevalence worldwide. However, the causes of CD remain incompletely understood. We identified CD-related metabolites, inflammatory factors, and key genes by Mendelian randomization (MR), multi-omics integration, machine learning (ML), and SHAP. METHODS: We first performed a mediation MR analysis on 1400 serum metabolites, 91 inflammatory factors, and CD. We found that certain phospholipids are causally related to CD. In the scRNA-seq data, monocytes were categorized into high and low metabolism groups based on their glycerophospholipid metabolism scores. The differentially expressed genes of these two groups of cells were extracted, and transcription factor prediction, cell communication analysis, and GSEA analysis were performed. After further screening of differentially expressed genes (FDR<0.05, log2FC>1), least absolute shrinkage and selection operator (LASSO) regression was performed to obtain hub genes. Models for hub genes were built using the Catboost, XGboost, and NGboost methods. Further, we used the SHAP method to interpret the models and obtain the gene with the highest contribution to each model. Finally, qRT-PCR was used to verify the expression of these genes in the peripheral blood mononuclear cells (PBMC) of CD patients and healthy subjects. RESULT: MR results showed 1-palmitoyl-2-stearoyl-gpc (16:0/18:0) levels, 1-stearoyl-2-arachidonoyl-GPI (18:0/20:4) levels, 1-arachidonoyl-gpc (20:4n6) levels, 1-palmitoyl-2-arachidonoyl-gpc (16:0/20:4n6) levels, and 1-arachidonoyl-GPE (20:4n6) levels were significantly associated with CD risk reduction (FDR<0.05), with CXCL9 acting as a mediation between these phospholipids and CD. The analysis identified 19 hub genes, with Catboost, XGboost, and NGboost achieving AUC of 0.91, 0.88, and 0.85, respectively. The SHAP methodology obtained the three genes with the highest model contribution: G0S2, S100A8, and PLAUR. The qRT-PCR results showed that the expression levels of S100A8 (p = 0.0003), G0S2 (p < 0.0001), and PLAUR (p = 0.0141) in the PBMC of CD patients were higher than healthy subjects. CONCLUSION: MR findings suggest that certain phospholipids may lower CD risk. G0S2, S100A8, and PLAUR may be potential pathogenic genes in CD. These phospholipids and genes could serve as novel diagnostic and therapeutic targets for CD.
RESUMO
Features of black phosphorous (BP) nano sheets such as enhancing mineralization and reducing cytotoxicity in bone regeneration field have been reported. Thermo-responsive FHE hydrogel (mainly composed of oxidized hyaluronic acid (OHA), poly-ε-L-lysine (ε-EPL) and F127) also showed a desired outcome in skin regeneration due to its stability and antibacterial benefits. This study investigated the application of BP-FHE hydrogel in anterior cruciate ligament reconstruction (ACLR) both in in vitro and in vivo, and addressed its effects on tendon and bone healing. This BP-FHE hydrogel is expected to bring the benefits of both components (thermo-sensitivity, induced osteogenesis and easy delivery) to optimize the clinical application of ACLR and enhance the recovery. Our in vitro results confirmed the potential role of BP-FHE via significantly increased rBMSC attachment, proliferation and osteogenic differentiation with ARS and PCR analysis. Moreover, In vivo results indicated that BP-FHE hydrogels can successfully optimize the recovery of ACLR through enhancing osteogenesis and improving the integration of tendon and bone interface. Further results of Biomechanical testing and Micro-CT analysis [bone tunnel area (mm2) and bone volume/total volume (%)] demonstrated that BP can indeed accelerate bone ingrowth. Additionally, histological staining (H&E, Masson and Safranin O/fast green) and immunohistochemical analysis (COL I, COL III and BMP-2) strongly supported the ability of BP to promote tendon-bone healing after ACLR in murine animal models.
RESUMO
PURPOSE: To explore the application value of voxel-based morphometric (VBM) in prenatal diagnosis of microcephaly. METHODS: A retrospective study of magnetic resonance imaging of fetuses with microcephaly was performed using a single-shot fast spin echo sequence; semiautomatic segmentation of grey matter (GM), white matter (WM), and cerebrospinal fluid (CSF); calculation of their volumes; and VBM analysis of their GM. Two independent samples t-test was used to statistically analyse the fetal GM volume in the microcephaly and normal control groups. Total intracranial volume (TIV), GM volume, WM volume, and CSF volume were linearly regressed against gestational age and compared between the two groups. RESULTS: In the fetus with microcephaly, GM volume of frontal lobe, temporal lobe, cuneus, anterior central gyrus, and posterior central gyrus decreased significantly (P < 0.001, corrected by family-wise error at mass level). The GM volume of microcephaly was significantly lower than that of the control group (except for 28 weeks of gestation) (P < 0.05). TIV, GM volume, WM volume, and CSF volume were all positively correlated with gestational age, and the curves in the microcephaly group were all lower than those in the control group. CONCLUSION: Compared with the normal control group, the GM volume of microcephaly fetuses decreased, and there were significant differences in many brain regions through VBM analysis.
Assuntos
Microcefalia , Malformações do Sistema Nervoso , Humanos , Gravidez , Feminino , Microcefalia/diagnóstico por imagem , Estudos Retrospectivos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Imageamento por Ressonância Magnética/métodos , Feto/diagnóstico por imagemRESUMO
BACKGROUND: Rotator cuff tear size, fatty infiltration, and scapular morphology are correlated with tendon healing and functional outcomes after arthroscopic repair; however, the association between anteroposterior acromial coverage and the clinical outcomes of anteroposterior massive rotator cuff tears (AP-MRCTs; involving all 3 tendons) remains unclear. PURPOSE: To identify the association between AP acromial coverage and functional and radiological outcomes after arthroscopic repair of AP-MRCTs. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 98 patients who underwent arthroscopic repair of AP-MRCTs between January 2015 and December 2020 were included in the study and classified according to whether anterior acromial coverage (AAC) was anterior (46 patients; positive AAC group) or posterior (52 patients; negative AAC group) to the scapular line on true lateral shoulder radiographs. Demographic characteristics, surgical details, and functional outcomes were prospectively collected. Acromial morphological features, global tear extension (GTE), the global fatty infiltration index (GFII), tendon integrity after repair, proximal humeral migration, and glenohumeral abduction were measured and calculated on radiographs or magnetic resonance imaging scans preoperatively and at 2 years postoperatively. Multivariate logistic regression was performed to identify the independent risk factors of a rotator cuff retear. RESULTS: The positive AAC group showed larger AAC, posterior acromial tilt, and anterior acromial slope as well as smaller posterior acromial coverage compared with the negative AAC group. Postoperatively, the American Shoulder and Elbow Surgeons score (82.5 ± 8.3 vs 77.2 ± 11.5, respectively; P = .013), active abduction (157.8°± 27.1° vs 142.7°± 39.6°, respectively; P = .048), and glenohumeral abduction (45.6°± 10.4° vs 39.7°± 14.9°, respectively; P = .041) in the positive AAC group were significantly higher than those in the negative AAC group, while the retear rate (23.9% vs 44.2%, respectively; P = .035) and proximal humeral migration (1.7 ± 1.0 vs 2.3 ± 1.2 mm, respectively; P = .006) were significantly lower in the positive AAC group than in the negative AAC group. Smaller AAC (odds ratio [OR], 0.93 [95% CI, 0.87-1.00]; P = .040), larger GTE (OR, 1.03 [95% CI, 1.01-1.06]; P = .017), and a higher GFII (OR, 3.49 [95% CI, 1.09-11.19]; P = .036) were associated with an increased risk of a rotator cuff retear. CONCLUSION: Increased AAC was associated with a lower retear rate and better functional outcomes after arthroscopic repair of AP-MRCTs. A preliminary risk evaluation integrating GTE, the GFII, and AAC is recommended to consider the necessity of additional procedures for patients in need of arthroscopic rotator cuff repair.
Assuntos
Lacerações , Lesões do Manguito Rotador , Humanos , Lesões do Manguito Rotador/diagnóstico por imagem , Lesões do Manguito Rotador/cirurgia , Estudos de Coortes , Radiografia , Acrômio/diagnóstico por imagem , Acrômio/cirurgia , Manguito Rotador/diagnóstico por imagem , Manguito Rotador/cirurgiaRESUMO
Purpose: To determine whether rotator cuff tear (RCT) patterns and scapular morphologic characteristics are associated with acetabularization of the coracoacromial arch when the remaining rotator cuff cannot stabilize the humeral head centered on the glenoid. Methods: Thirty-two consecutive patients incapable of stabilizing the humeral head within the native glenoid were included and divided into 2 groups: unstable glenohumeral fulcrum kinematics (GHFK) group (n = 16; absence of acetabularization of the coracoacromial arch) and captured GHFK group (n = 16; the presence of acetabularization of the coracoacromial arch). Magnetic resonance imaging (MRI) analysis included tear locations, tear extensions (anterior, posterior, and global), and fatty infiltration of the rotator cuff muscles. Plain radiographic and computed tomography image measurements included acromiohumeral distance, critical shoulder angle, lateral acromial angle, acromial index, acromial tilt, acromial slope angle, anterior and posterior acromial coverage, and coracoacromial ligament coverage. Results: Patient demographic characteristics did not differ significantly (P > .05). No differences in tear patterns were found between patients with unstable GHFK and those with captured GHFK on MRI (P > .05). Scapular morphologic parameter measurements showed significant differences between the unstable and captured GHFK groups: anterior acromial coverage (-5.8 ± 13.8° vs. 13.8 ± 11.3°, P < .001), acromial tilt (34.9 ± 8.9° vs. 26.7 ± 6.2°; P = .005), and acromial slope angle (24.5 ± 8.1° vs. 33.5 ± 7.9°, P = .003). Conclusion: Scapular morphologic characteristics, rather than RCT patterns, were associated with the development of acetabularization of the coracoacromial arch when the remaining rotator cuff could not stabilize the humeral head. Patients with captured GHFK exhibited larger anterior acromial coverage, smaller acromial tilt, and a more curved acromion than those with unstable GHFK.
RESUMO
BACKGROUND: Because of poor clinical outcomes, rotator cuff healing in patients with osteoporosis has recently gained attention. Antiresorptive therapy for osteoporosis has been reported to improve healing after repair. However, the comparative effectiveness of anabolic and antiresorptive agents has not been investigated. HYPOTHESIS: Anabolic therapy with abaloparatide (ABL) would outperform antiresorptive therapy with denosumab (Dmab) to improve rotator cuff healing in the osteoporotic status. STUDY DESIGN: Controlled laboratory study. METHODS: A chronic rotator cuff tear model was established in ovariectomy-induced postmenopausal osteoporotic rats. Then, bilateral rotator cuff repairs were conducted in all experimental rats, which were randomly divided into control (CON), Dmab, and ABL groups to receive the corresponding subcutaneous injections. The rats sacrificed at 2 weeks (the early healing period) were used to detect osteoblast and osteoclast activities, related gene expression (osteoclastogenesis, osteogenesis, and chondrogenesis), new bone formation, and mineralization. In the rats sacrificed at 4 and 8 weeks, the bone mineral density and bone architecture at the repaired site were assessed by micro-computed tomography, and rotator cuff healing was evaluated using histological and biomechanical analyses. RESULTS: At 8 weeks, significantly higher failure load and stiffness were observed in the ABL (25.13 ± 3.54 N, P < .001; 21.65 ± 3.08 N/mm, P < .001; respectively), and Dmab (21.21 ± 2.55 N, P < .001; 16.15 ± 2.07 N/mm, P = .008; respectively) groups than in the CON group (13.36 ± 1.70 N; 11.20 ± 2.59 N/mm; respectively), whereas the ABL treatment provided better failure load and stiffness than Dmab (P = .019; P = .003). Although tendon-to-bone healing was improved by Dmab, the most mature tendon insertion at the interface was observed in the ABL group, including a more organized collagen and fibrocartilage and higher bone quality. ABL significantly promoted bone remodeling via coupling between osteoclasts and osteoblasts (osteoblast to osteoclast ratio: 4.80 ± 0.39; P = .022), thereby stimulating more new bone formation and mineralization at the tendon-to-bone healing interface than Dmab (osteoblast to osteoclast ratio: 3.21 ± 0.75) at 2 weeks. Moreover, ABL had significant effects on gene expression [Runt-realted transcription factor 2 (Runx2, collagen type I-alpha 1 (Col1A1]), and sclerostin for osteogenesis; aggrecan and collagen type II (Col2) for chondrogenesis] in mineralized tissues, indicative of enhanced bone and fibrocartilage formation when compared with the CON and Dmab groups. CONCLUSION: ABL promoted rotator cuff healing in osteoporotic rats by significantly increasing the mineralized tissue quality and collagen maturity at the reattachment site, leading to improved biomechanical properties, and was superior to Dmab in both biomechanical and histological analyses. CLINICAL RELEVANCE: Anabolic therapy with ABL may outperform antiresorptive therapy with Dmab in improving outcomes after rotator cuff repair in osteoporotic patients.
Assuntos
Anabolizantes , Osteoporose , Lesões do Manguito Rotador , Anabolizantes/farmacologia , Animais , Fenômenos Biomecânicos , Remodelação Óssea , Colágeno/metabolismo , Denosumab/farmacologia , Feminino , Humanos , Proteína Relacionada ao Hormônio Paratireóideo , Ratos , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/tratamento farmacológico , Lesões do Manguito Rotador/cirurgia , Cicatrização , Microtomografia por Raio-XRESUMO
Brain atlases are of fundamental importance for analyzing the dynamic neurodevelopment in fetal brain studies. Since the brain size, shape, and anatomical structures change rapidly during the prenatal period, it is essential to construct a spatiotemporal (4D) atlas equipped with tissue probability maps, which can preserve sharper early brain folding patterns for accurately characterizing dynamic changes in fetal brains and provide tissue prior informations for related tasks, e.g., segmentation, registration, and parcellation. In this work, we propose a novel unsupervised age-conditional learning framework to build temporally continuous fetal brain atlases by incorporating tissue segmentation maps, which outperforms previous traditional atlas construction methods in three aspects. First, our framework enables learning age-conditional deformable templates by leveraging the entire collection. Second, we leverage reliable brain tissue segmentation maps in addition to the low-contrast noisy intensity images to enhance the alignment of individual images. Third, a novel loss function is designed to enforce the similarity between the learned tissue probability map on the atlas and each subject tissue segmentation map after registration, thereby providing extra anatomical consistency supervision for atlas building. Our 4D temporally-continuous fetal brain atlases are constructed based on 82 healthy fetuses from 22 to 32 gestational weeks. Compared with the atlases built by the state-of-the-art algorithms, our atlases preserve more structural details and sharper folding patterns. Together with the learned tissue probability maps, our 4D fetal atlases provide a valuable reference for spatial normalization and analysis of fetal brain development.
RESUMO
Developing a high-performance nonprecious metal electrocatalyst for water splitting is a strong demand for the large-scale application of electrochemical H2 production. In this work, we design a facile and scalable strategy to activate titanium metal for the hydrogen evolution reaction (HER) in alkaline media through incorporating hydrogen into the α-Ti crystal lattice by H2 plasma bombardment. Benefiting from the accelerated charge transfer and enlarged electrochemical surface area after H2 plasma treatment, the H-incorporated Ti shows remarkably enhanced HER activity with a much lower overpotential at -10 mA cm-2 by 276 mV when compared to the pristine Ti. It is revealed that the retention of the incorporated H(D) atoms in the Ti crystal lattice during HER accounts for the durable feature of the catalyst. Density functional theory calculations demonstrate the effectiveness of hydrogen incorporation in tuning the adsorption energy of reaction species via charge redistribution. Our work offers a novel route to activate titanium or other metals by H incorporation through a controllable H2 plasma treatment to tune the electronic structure for water splitting reactions.
RESUMO
It is important to get fast and quantitative compositional depth profiles for the boundary layer of the corroded specimen in order to understand the corrosion process and mechanism due to liquid lithium induced corrosion problems to structural material of fusion reactors. In this work, calibration-free laser-induced breakdown spectroscopy (CF-LIBS) is introduced to investigate the compatibility of CLF-1(China low-activation Ferritic steel) exposed in liquid lithium at 500 °C for 500 h. The results show that CF-LIBS constitutes an effective technique to observe the corrosion layer of specimens which are non-uniform and the elements of matrix show gradient distribution from the boundary to the inner layer. The concentration was 82-95 wt.% Fe, 5-12 wt.% Cr, 0.45-0.85 wt.% Mn, 1.6-1.1 wt.% W, 0.11-0.16 wt.% V, and <0.2 wt.% Li along the longitudinal corrosion depth for the corrode CLF-1. The results reveal the quantitative elemental variation trend of CLF-1 in the lithium corrosion process and indicate that the CF-LIBS approach can be applied to the analysis of composition in multi-element materials.
RESUMO
Receptor-interacting serine/threonine-protein kinase 3 (RIPK3) is a central protein in necroptosis with great potential as a target for treating necroptosis-associated diseases, such as Crohn's disease. However, blockade of RIPK3 kinase activity leads to unexpected RIPK3-initiated apoptosis. Herein, we found that PP2, a known SRC inhibitor, inhibits TNF-α-induced necroptosis without initiating apoptosis. Further investigation showed that PP2 acts as an inhibitor of not only SRC but also RIPK3. PP2 does not disturb the integrity of the RIPK1-RIPK3-mixed lineage kinase domain-like pseudokinase (MLKL) necroptosome or the autophosphorylation of RIPK3 at T231/S232 but disrupts RIPK3 oligomerization, thereby impairing the phosphorylation and oligomerization of MLKL. These results demonstrate the essential role of RIPK3 oligomerization in necroptosis and suggest a potential RIPK3 oligomerization-targeting strategy for therapeutic development.
Assuntos
Apoptose , Necroptose/efeitos dos fármacos , Multimerização Proteica/efeitos dos fármacos , Pirimidinas/farmacologia , Proteína Serina-Treonina Quinases de Interação com Receptores/química , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Camundongos , Fosforilação/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Quinases da Família src/antagonistas & inibidoresRESUMO
In this study, an economic, sustainable, and green synthesis method of multiporous carbons from agricultural waste, water caltrop shell (denoted as WCS), was presented. To prepare the WCS biochar, the dried WCS was first carbonized to a microporous carbon with a surface area of around 230 m2 g-1 by using a top-lit-updraft method. Then, the microporous WCS biochar was directly mixed with an appropriate amount of ZnO nanoparticles and KOH as activating agents via a solvent-free physical blending route. After further activation at 900 °C, the resulted carbons possess both micropores and mesopores that were named as WCS multiporous carbons. The carbon yield of the prepared WCS multiporous carbons with high surface area in the range of 1175-1537 m2 g-1 is up to 50%. Furthermore, the micropore/mesopore surface area ratio can be simply tuned by controlling the ZnO content. For supercapacitor applications, the as-prepared WCS multiporous carbon electrodes showed high specific capacitance (128 F g-1 at 5 mV s-1) with a good retention rate at 500 mV s-1 scan rate (>60% compared to the capacitance at 5 mV s-1) and low Ohmic resistance in a 1.0 M LiClO4/PC electrolyte. In addition to the ZnO nanoparticles, CaCO3 nanoparticles with low environmental impact were also used to prepare the WCS multiporous carbons. The assembled supercapacitors also demonstrate high specific capacitance (102 F g-1 at 5 mV s-1) and good retention rate (â¼70%).
RESUMO
In the tissue engineering of cartilage, scaffolds with appropriate elasticity and controlled-release properties are essential. Herein, we synthesized a poly(ether-ester-urethane)urea scaffold with a pendant amino group (PEEUUN) through a de-protection process from PEEUU-Boc polymers and grafted kartogenin (KGN) onto the PEEUUN scaffolds (PEEUUN-KGN). Characterization, performance tests, scaffold biocompatibility analysis, and chondrogenesis evaluation both in vitro and in vivo were conducted. The results revealed that the PEEUUN-KGN scaffolds were degradable and three-dimensional (3D) with interconnected pores, and possessed good elasticity, as well as excellent cytocompatibility. Meanwhile, KGN on the PEEUUN-KGN scaffolds underwent stable sustained release for a long time and promoted human umbilical cord mesenchymal stem cells (HUCMSCs) to differentiate into chondrocytes in vitro, thus enhancing cartilage regeneration in vivo. In conclusion, the present PEEUUN-KGN scaffolds would have application potential for cartilage tissue engineering.
Assuntos
Materiais Biocompatíveis/química , Cartilagem Elástica/química , Polímeros/química , Engenharia Tecidual , Alicerces Teciduais/química , Ureia/química , Animais , Materiais Biocompatíveis/síntese química , Células Cultivadas , Preparações de Ação Retardada , Ésteres/síntese química , Ésteres/química , Éteres/síntese química , Éteres/química , Humanos , Estrutura Molecular , Tamanho da Partícula , Polímeros/síntese química , Porosidade , Coelhos , Propriedades de Superfície , Ureia/análogos & derivados , Uretana/síntese química , Uretana/químicaRESUMO
Hydrophobic surfaces were successfully fabricated on pure nickel substrates by a one-step chemical etching process with different acidic solutions. The static water contact angle (SCA) of the etched Ni surfaces reached higher than 125°, showing excellent hydrophobicity. The examination of surface chemical compositions implied that there were almost no polar moieties on the surface after chemical etching, except part of the surface was oxidized. After chemical etching, the nickel surfaces became much rough with packed terrace-/crater-/thorn-like clusters. According to the analysis of surface composition and morphology, the hydrophobicity was evidently attributed to the rough microstructures on the etched Ni surface. The best hydrophobicity on Ni surface was produced with the SCAs as high as 140.0° by optimizing the etching time and etchants. The results demonstrate that it is possible to construct hydrophobic surfaces on hydrophilic substrates by tailoring the surface microstructure using a simple chemical etching process without any further hydrophobic modifications by low surface energy materials.
RESUMO
A repeatable self-healing epoxy composite mechanically enhanced by graphene nanosheets (GNS) was prepared from an epoxy monomer with Diels-Alder (DA) bonds, octanediol glycidyl ether (OGE) and polyether amine (D230). The GNS/epoxy composites, with a maximum tensile modulus of 14.52 ± 0.45 MPa and elongation at break more than 100%, could be healed several times under Infrared (IR) light with the healing efficiency as high as 90% through the molecule chain mobility and the rebonding of reversible DA bonds between furan and maleimide. Also, they displayed excellent recyclable ability by transforming into a soluble polymer, which offers a wide range of possibilities to produce epoxy flexible materials with healing and removable abilities.