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1.
Eur Radiol ; 2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38460014

RESUMEN

OBJECTIVES: The study aimed to compare the diagnostic accuracies of 2-[18F]FDG PET/CT and contrast-enhanced CT (ceCT) after neoadjuvant chemotherapy (NACT) in advanced ovarian cancer (OC). MATERIALS AND METHODS: This study consisted historical observational cohort and prospective validation cohort. Patients with newly diagnosed stage III-IV OC scheduled for NACT were recruited, with imaging performed after three to six cycles of NACT before interval debulking surgery. Nineteen regions in the abdominopelvic cavity were scored for the presence and absence of disease, referenced to the intra-operative findings or histological specimens. Diagnostic metrics were compared using McNemar's test. RESULTS: In the historical cohort (23 patients, age 58 ± 13), 2-[18F]FDG PET had an overall accuracy (Acc) 82%, sensitivity (Sen) 38%, specificity (Spe) 97%, positive predictive value (PPV) 79% and negative predictive value (NPV) 82%; ceCT had an overall Acc 86%, Sen 64%, Spe 93%, PPV 75% and NPV 89%. In the prospective cohort (46 patients, age 59 ± 9), 2-[18F] FDG PET had an overall Acc 87%, Sen 48%, Spe 98%, PPV 84% and NPV 88%; ceCT had an overall Acc 89%, Sen 66%, Spe 95%, PPV 77% and NPV 91%. No significant difference was demonstrated between the two imaging modalities (p > 0.05). High false-negative rates were observed in the right subdiaphragmatic space, omentum, bowel mesentery and serosa. High omental metabolic uptake after NACT was associated with histological non-responders (p < 0.05). CONCLUSION: 2-[18F]FDG PET/CT had no additional value over ceCT with comparable diagnostic accuracy in detecting disease after NACT in advanced OC. CLINICAL RELEVANCE STATEMENT: 2-[18F]FDG PET/CT is not superior to contrast-enhanced CT in determining disease after neoadjuvant chemotherapy in advanced ovarian cancer; contrast-enhanced CT should be suffice for surgical planning before interval debulking surgery. KEY POINTS: • Additional value of 2-[18F]FDG PET/CT over contrast-enhanced CT is undefined in detecting disease after neoadjuvant chemotherapy. • 2-[18F]FDG PET/CT has comparable diagnostic accuracy compared to contrast-enhanced CT. • Contrast-enhanced CT will be suffice for surgical planning after neoadjuvant chemotherapy.

2.
Microbiol Immunol ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886542

RESUMEN

The thymus, a site to culture the naïve T lymphocytes, is susceptible to atrophy or involution due to aging, inflammation, and oxidation. Epigallocatechin-3-gallate (EGCG) has been proven to possess anti-inflammatory, antioxidant, and antitumor activity. Here, we investigate the effects of EGCG on thymic involution induced by lipopolysaccharide (LPS), an endotoxin derived from Gram-negative bacteria. The methodology included an in vivo experiment on female Kunming mice exposed to LPS and EGCG. Morphological assessment of thymic involution, immunohistochemical detection, and thymocyte subsets analysis by flow cytometry were further carried out to evaluate the potential role of EGCG on the thymus. As a result, we found that EGCG alleviated LPS-induced thymic atrophy, increased mitochondrial membrane potential and superoxide dismutase levels, and decreased malondialdehyde and reactive oxygen species levels. In addition, EGCG pre-supplement restored the ratio of thymocyte subsets, the expression of autoimmune regulator, sex-determining region Y-box 2, and Nanog homebox, and reduced the number of senescent cells and collagen fiber deposition. Western blotting results indicated that EGCG treatment elevated LPS-induced decrease in pAMPK, Sirt1 protein expression. Collectively, EGCG relieved thymus architecture and function damaged by LPS via regulation of AMPK/Sirt1 signaling pathway. Our findings may provide a new strategy on protection of thymus from involution caused by LPS by using EGCG. And EGCG might be considered as a potential agent for the prevention and treatment of thymic involution.

3.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33602813

RESUMEN

The assembly and jamming of magnetic nanoparticles (NPs) at liquid-liquid interfaces is a versatile platform to endow structured liquid droplets with a magnetization, i.e., producing ferromagnetic liquid droplets (FMLDs). Here, we use hydrodynamics experiments to probe how the magnetization of FMLDs and their response to external stimuli can be tuned by chemical, structural, and magnetic means. The remanent magnetization stems from magnetic NPs jammed at the liquid-liquid interface and dispersed NPs magneto-statically coupled to the interface. FMLDs form even at low concentrations of magnetic NPs when mixing nonmagnetic and magnetic NPs, since the underlying magnetic dipole-driven clustering of magnetic NP-surfactants at the interface produces local magnetic properties, similar to those found with pure magnetic NP solutions. While the net magnetization is smaller, such a clustering of NPs may enable structured liquids with heterogeneous surfaces.

4.
J Am Chem Soc ; 145(41): 22639-22648, 2023 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-37788450

RESUMEN

Disulfide bonds are widely found in natural peptides and play a pivotal role in stabilizing their secondary structures, which are highly associated with their biological functions. Herein, we introduce a light-mediated strategy to effectively control the formation of disulfides. Our strategy is based on 2-nitroveratryl (oNv), a widely used photolabile motif, which serves both as a photocaging group and an oxidant (after photolysis). We demonstrated that irradiation of oNv-caged thiols with UV light could release free thiols that are rapidly oxidized by locally released byproduct nitrosoarene, leading to a "break-to-bond" fashion. This strategy is highlighted by the in situ restoration of the antimicrobial peptide tachyplesin I (TPI) from its external disulfide-caged analogue TPI-1. TPI-1 exhibits a distorted structure and a diminished function. However, upon irradiation, the ß-hairpin structure and membrane activity of TPI were largely restored via rapid intramolecular disulfide formation. Our study proposes a powerful method to regulate the conformation and function of peptides in a spatiotemporal manner, which has significant potential for the design of disulfide-centered light-responsive systems.


Asunto(s)
Disulfuros , Compuestos de Sulfhidrilo , Disulfuros/química , Estructura Secundaria de Proteína , Compuestos de Sulfhidrilo/química
5.
J Org Chem ; 88(19): 13645-13654, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37681260

RESUMEN

A copper/PyBisulidine-catalyzed enantioselective alkynylation of electrophilic pyrazole-4,5-dione with terminal alkynes has been developed. Chiral tertiary propargylic alcohols bearing the pyrazolone motif were prepared with yields (up to 99%) and enantioselectivities (up to 99% ee). The prominent feature of this protocol includes its mild reaction conditions and good stereoselectivities. The nonlinear effect study showed that the catalytically active specie was a monomeric catalyst and that the excess copper activated the alkynes through the π-system.

6.
Org Biomol Chem ; 21(30): 6225-6229, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37482886

RESUMEN

A Ni/PyBisulidine catalyzed asymmetric Michael addition of 3-acyloxy-2-oxindoles to nitroalkenes has been developed. Various quaternary substituted 3-acyloxy-2-oxindoles were obtained with excellent yields and diastereo- and enantioselectivities in a low-toxic green solvent, ethyl acetate, with a low catalyst loading (1 mol%). The reaction process is air and moisture tolerant. The substrate scope was also extended to α,ß-disubstituted nitroalkenes and 3-hydroxy-2-oxindoles, and good results were obtained.

7.
Epidemiol Infect ; 151: e186, 2023 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-37881897

RESUMEN

Many studies have investigated the positivity rate of hepatitis B surface antibody (HBsAb) after hepatitis B vaccine (HepB) immunization. However, the antibody level, assessed monthly or at more frequent intervals after each of the three doses, particularly within the first year after birth, has not been previously reported. To elucidate the level of antibody formation at various times after vaccination, the current study used the available detection data of HBsAb in hospitalized children to analyze the HBsAb level after immunization combined with their vaccination history. Both the positivity rate and geometric mean concentration (GMC) increased sequentially with immunization doses, reaching their peaks earlier after the third dose than after the first two doses, and the rate of HBsAb positivity was able to reach 100% between 11 and 90 days after completing the three doses of HepB. Within one year after receiving the three doses, the antibody positivity rate and GMC were maintained above 90% and 100 mIU/mL, respectively, and subsequently steadily declined, reaching the lowest value in the 9th and 10th years. The current findings reveal, in more detail, the level of antibody formation at different times following each dose of HepB in hospitalized children, particularly in the age group up to one year after vaccination. For the subjects of this study, we prefer to believe that the proportion of HBsAb non-response should be less than 5% after full immunization with HepB, provided that the appropriate time for blood collection is chosen.


Asunto(s)
Antígenos de Superficie de la Hepatitis B , Hepatitis B , Cricetinae , Animales , Niño , Humanos , Estudios Retrospectivos , Inmunización Secundaria , Niño Hospitalizado , Hepatitis B/prevención & control , Cricetulus , Antígenos del Núcleo de la Hepatitis B , Estudios de Seguimiento , Células CHO , Vacunación , Vacunas contra Hepatitis B , Anticuerpos contra la Hepatitis B
8.
Pacing Clin Electrophysiol ; 46(5): 425-431, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36959770

RESUMEN

OBJECTIVE: In this study, the efficacy and safety of salvianolate were compared with enoxaparin in the prevention of perioperative deep vein thrombosis in gastrointestinal surgery. METHODS: From October 2017 to September 2019, 563 patients who underwent gastrointestinal surgery were collected. Based on the inclusion and exclusion criteria, 119 patients were divided into two groups: enoxaparin group (n = 65) and salvianolate group (n = 54). Comparisons were made regarding the outcomes: prothrombin time (PT), prothrombin activity (PTA), international normalized ratio (INR), activated partial thromboplastin time (APTT), fibrinogen (FIB), thrombin time (TT), D-dimer level (D-D), platelet count (PLT), hematokrit (HCT), and incidence of deep vein thrombosis (DVT). RESULTS: The main outcomes showed no significance between enoxaparin group and salvianolate group (p > .05). The incidence of DVT in salvianolate group was 1.85%, significantly lower than that in enoxaparin group (12.3%) (p < .05). No serious adverse reactions occurred in the two groups during treatment. CONCLUSION: Compared with enoxaparin, salvianolate has an advantage in the prevention of perioperative thrombosis in gastrointestinal surgery with a lower incidence of DVT.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo , Enoxaparina , Extractos Vegetales , Trombosis de la Vena , Humanos , Extractos Vegetales/administración & dosificación , Enoxaparina/administración & dosificación , Anticoagulantes/administración & dosificación , Atención Perioperativa , Trombosis de la Vena/epidemiología , Trombosis de la Vena/prevención & control , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Tiempo de Protrombina , Incidencia , Estudios Retrospectivos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , China/epidemiología , Resultado del Tratamiento
9.
Sensors (Basel) ; 23(20)2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37896573

RESUMEN

Predictive maintenance is a proactive approach to maintenance in which equipment and machinery are monitored and analyzed to predict when maintenance is needed. Instead of relying on fixed schedules or reacting to breakdowns, predictive maintenance uses data and analytics to determine the appropriate time to perform maintenance activities. In industrial applications, machine boxes can be used to collect and transmit the feature information of manufacturing machines. The collected data are essential to identify the status of working machines. This paper investigates the design and implementation of a machine box based on the ROS framework. Several types of communication interfaces are included that can be adopted to different sensor modules for data sensing. The collected data are used for the application on predictive maintenance. The key concepts of predictive maintenance include data collection, a feature analysis, and predictive models. A correlation analysis is crucial in a feature analysis, where the dominant features can be determined. In this work, linear regression, a neural network, and a decision tree are adopted for model learning. Experimental results illustrate the feasibility of the proposed smart machine box. Also, the remaining useful life can be effectively predicted according to the trained models.

10.
Nano Lett ; 22(13): 5538-5543, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35766622

RESUMEN

Ferrofluids (FFs) can adapt their shape to a magnetic field. However, they cannot maintain their shape when the magnetic field is removed. Here, with a magneto-responsive and reconfigurable interfacial self-assembly (MRRIS) process, we show that FFs can be structured by a magnetic field and maintain their shape, like solids, after removing the magnetic field. The competing self-assembly of magnetic and nonmagnetic nanoparticles at the liquid interface endow FFs with both reconfigurability and structural stability. By manipulating the external magnetic field, we show that it is possible to "write" and "erase" the shape of the FFs remotely and repeatedly. To gain an in-depth understanding of the effect of MRRIS on the structure of FFs, we systematically study the shape variation of these liquids under both the static and dynamic magnetic fields. Our study provides a simple yet novel way of manipulating FFs and opens opportunities for the fabrication of all-liquid devices.


Asunto(s)
Coloides , Nanopartículas , Coloides/química , Campos Magnéticos , Magnetismo , Nanopartículas/química
11.
Int J Mol Sci ; 24(4)2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36834587

RESUMEN

The mechanism of systemic osteoporosis caused by chronic infection is not completely clear, and there is a lack of reasonable interventions for this disease. In this study, heat-killed S. aureus (HKSA) was applied to simulate the inflammation caused by the typical clinical pathogen and to explore the mechanism of systemic bone loss caused by it. In this study, we found that the systemic application of HKSA caused bone loss in mice. Further exploration found that HKSA caused cellular senescence, telomere length shortening, and telomere dysfunction-induced foci (TIF) in limb bones. As a well-known telomerase activator, cycloastragenol (CAG) significantly alleviated HKSA-induced telomere erosion and bone loss. These results suggested that telomere erosion in bone marrow cells is a possible mechanism of HKSA-induced bone loss. CAG may protect against HKSA-induced bone loss by alleviating telomere erosion in bone marrow cells.


Asunto(s)
Infecciones Estafilocócicas , Telomerasa , Animales , Ratones , Staphylococcus aureus , Calor , Inflamación , Células de la Médula Ósea , Telómero , Senescencia Celular
12.
Angew Chem Int Ed Engl ; 62(38): e202308853, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37503554

RESUMEN

Nanoparticles (NPs) transfer is usually induced by adding ligands to modify NP surfaces, but aggregation of NPs oftentimes hampers the transfer. Here, we show that aggregation during NP phase transfer does not necessarily result in transfer failure. Using a model system comprising gold NPs and amphiphilic polymers, we demonstrate an unusual mechanism by which NPs can undergo phase transfer from the aqueous phase to the organic phase via a single-aggregation-single pathway. Our discovery challenges the conventional idea that aggregation inhibits NP transfer and provides an unexpected pathway for transferring larger-sized NPs (>20 nm). The charged amphiphilic polymers effectively act as chaperons for the NP transfer and offer a unique way to manipulate the dispersion and distribution of NPs in two immiscible liquids. Moreover, by intentionally jamming the NP-polymer assembly at the liquid/liquid interface, the transfer process can be inhibited.

13.
Angew Chem Int Ed Engl ; 62(36): e202303789, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37198522

RESUMEN

Stabilizing liquids based on supramolecular assembly (non-covalent intermolecular interactions) has attracted significant interest, due to the increasing demand for soft, liquid-based devices where the shape of the liquid is far from the equilibrium spherical shape. The components comprising these interfacial assemblies must have sufficient binding energies to the interface to prevent their ejection from the interface when the assemblies are compressed. Here, we highlight recent advances in structuring liquids based on non-covalent intermolecular interactions. We describe some of the progress made that reveals structure-property relationships. In addition to treating advances, we discuss some of the limitations and provide a perspective on future directions to inspire further studies on structured liquids based on supramolecular assembly.

14.
Biophys J ; 121(16): 3146-3161, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35841144

RESUMEN

Cholesterol plays a unique role in the regulation of membrane organization and dynamics by modulating the membrane phase transition at the nanoscale. Unfortunately, due to their small sizes and dynamic nature, the effects of cholesterol-mediated membrane nanodomains on membrane dynamics remain elusive. Here, using ultrahigh-speed single-molecule tracking with advanced optical microscope techniques, we investigate the diffusive motion of single phospholipids in the live cell plasma membrane at the nanoscale and its dependency on the cholesterol concentration. We find that both saturated and unsaturated phospholipids undergo anomalous subdiffusion on the length scale of 10-100 nm. The diffusion characteristics exhibit considerable variations in space and in time, indicating that the nanoscopic lipid diffusion is highly heterogeneous. Importantly, through the statistical analysis, apparent dual-mobility subdiffusion is observed from the mixed diffusion behaviors. The measured subdiffusion agrees well with the hop diffusion model that represents a diffuser moving in a compartmentalized membrane created by the cytoskeleton meshwork. Cholesterol depletion diminishes the lipid mobility with an apparently smaller compartment size and a stronger confinement strength. Similar results are measured with temperature reduction, suggesting that the more heterogeneous and restricted diffusion is connected to the nanoscopic membrane phase transition. Our conclusion supports the model that cholesterol depletion induces the formation of gel-phase, solid-like membrane nanodomains. These nanodomains undergo restricted diffusion and act as diffusion obstacles to the membrane molecules that are excluded from the nanodomains. This work provides the experimental evidence that the nanoscopic lipid diffusion in the cell plasma membrane is heterogeneous and sensitive to the cholesterol concentration and temperature, shedding new light on the regulation mechanisms of nanoscopic membrane dynamics.


Asunto(s)
Colesterol , Membrana Dobles de Lípidos , Membrana Celular/metabolismo , Colesterol/metabolismo , Difusión , Membrana Dobles de Lípidos/metabolismo , Fosfolípidos/metabolismo
15.
Small ; 18(6): e2105017, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35142068

RESUMEN

To better exploit all-liquid 3D architectures, it is essential to understand dynamic processes that occur during printing one liquid in a second immiscible liquid. Here, the interfacial assembly and transition of 5,10,15,20-tetrakis(4-sulfonatophenyl) porphyrin (H6 TPPS) over time provides an opportunity to monitor the interfacial behavior of nanoparticle surfactants (NPSs) during all-liquid printing. The formation of J-aggregates of H4 TPPS2- at the interface and the interfacial conversion of the J-aggregates of H4 TPPS2- to H-aggregates of H2 TPPS4- is demonstrated by interfacial rheology and in situ atomic force microscopy. Equally important are the chromogenic changes that are characteristic of the state of aggregation, where J-aggregates are green in color and H-aggregates are red in color. In all-liquid 3D printed structures, the conversion in the aggregate state with time is reflected in a spatially varying change in the color, providing a simple, direct means of assessing the aggregation state of the molecules and the mechanical properties of the assemblies, linking a macroscopic observable (color) to mechanical properties.


Asunto(s)
Porfirinas , Porfirinas/química , Reología , Tensoactivos/química
16.
J Pharmacol Exp Ther ; 381(3): 257-265, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35398813

RESUMEN

To investigate therapeutic target for ligustrazine during liver fibrosis in an ethanol-induced biliary atresia rat model and transforming growth factor-ß (TGF-ß) induced hepatic stellate cell activation cell model, and the underlying mechanism, a total of 30 rats were randomly assigned into five groups (n = 6 per group): control, sham, ethanol-induced biliary atresia model, model plus pirfenidone, and model plus ligustrazine groups. The liver changes were assessed using H&E and Masson staining and transmission electron microscopy. Expression of miR-145 and mRNA and protein levels of TGF-ß/smads pathway-related proteins were detected. HSC-T6 cells were infected with LV-miR or rLV-miR-145 in the presence or absence of SMAD3 inhibitor SIS3 and treated with 2.5 ng/ml TGF-ß1 and then with ligustrazine. Collected cells were subjected to detect the expression of miR-145 and mRNA and protein expression levels of TGF-ß/smads pathway-related proteins. Ligustrazine rescued liver fibrogenesis and pathology for ethanol-caused bile duct injury, revealed by decreased α-smooth muscle actin and collagen I expression and liver tissue and cell morphology integrity. Further experiments showed that ligustrazine inhibited intrinsic and phosphorylated Smad2/3 protein expression and modification. Similar results were obtained in cells. In addition, ligustrazine altered miR-145 expression in both animal and cell models. Lentivirus mediated miR-145 overexpression and knockdown recombinant virus showed that miR-145 enhanced the TGF-ß/Smad pathway, which led to hepatic stellate cell activation, and ligustrazine blocked this activation. This work validated that ligustrazine-regulated miR-145 mediated TGF-ß/Smad signaling to inhibit the progression of liver fibrosis in a biliary atresia rat model and provided a new therapeutic strategy for liver fibrosis. SIGNIFICANCE STATEMENT: With an ethanol-induced biliary atresia rat model, ligustrazine was found to rescue liver fibrogenesis and pathology for ethanol caused bile duct injury, revealed by decreased α-smooth muscle actin and collagen I expression and liver tissue and cell morphology integrity. Furthermore, we found ligustrazine upregulated miR-145 expression and inhibited TGF-ß/SMAD signaling pathway both in vivo and in vitro. In addition, overexpression and knockdown of miR-145 confirmed that miR-145 is involved in the ligustrazine inhibition of liver fibrosis through the TGF-ß/SMAD signaling pathway.


Asunto(s)
Atresia Biliar , MicroARNs , Actinas/genética , Actinas/metabolismo , Animales , Atresia Biliar/metabolismo , Atresia Biliar/patología , Colágeno Tipo I/efectos adversos , Colágeno Tipo I/metabolismo , Modelos Animales de Enfermedad , Etanol/efectos adversos , Células Estrelladas Hepáticas/metabolismo , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Pirazinas , ARN Mensajero/metabolismo , Ratas , Transducción de Señal , Proteínas Smad/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Factores de Crecimiento Transformadores/efectos adversos , Factores de Crecimiento Transformadores/metabolismo
17.
Nano Lett ; 21(17): 7116-7122, 2021 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-34448588

RESUMEN

Fine control over the mechanical properties of thin sheets underpins transcytosis, cell shape, and morphogenesis. Applying these principles to artificial, liquid-based systems has led to reconfigurable materials for soft robotics, actuation, and chemical synthesis. However, progress is limited by a lack of synthetic two-dimensional membranes that exhibit tunable mechanical properties over a comparable range to that seen in nature. Here, we show that the bending modulus, B, of thin assemblies of nanoparticle surfactants (NPSs) at the oil-water interface can be varied continuously from sub-kBT to 106kBT, by varying the ligands and particles that comprise the NPS. We find extensive departure from continuum behavior, including enormous mechanical anisotropy and a power law relation between B and the buckling spectrum width. Our findings provide a platform for shape-changing liquid devices and motivate new theories for the description of thin-film wrinkling.


Asunto(s)
Nanopartículas , Tensoactivos , Anisotropía
18.
Int J Med Sci ; 18(16): 3808-3820, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34790057

RESUMEN

Background: Substantial evidence shows that crosstalk between cartilage and subchondral bone may play an important role in cartilage repair. Animal models have shown that hydroxyapatite-grafted-chitosan implant (HA-g-CS) and moderate-intensity exercise promote regeneration of osteochondral defects. However, no in vivo studies have demonstrated that these two factors may have a synergistic activity to facilitate subchondral bone remodeling in mice, thus supporting bone-cartilage repair. Questions: This study was to clarify whether HA-g-CS and moderate-intensity exercise might have a synergistic effect on facilitating (1) regeneration of osteochondral defects and (2) subchondral bone remodeling in a mouse model of osteochondral defects. Methods: Mouse models of osteochondral defects were created and divided into four groups. BC Group was subjected to no treatment, HC Group to HA-g-CS implantation into osteochondral defects, ME group to moderate-intensity treadmill running exercise, and HC+ME group to both HA-g-CS implantation and moderate-intensity exercise until sacrifice. Extent of subchondral bone remodeling at the injury site and subsequent cartilage repair were assessed at 4 weeks after surgery. Results: Compared with BC group, HC, ME and HC+ME groups showed more cartilage repair and thicker articular cartilage layers and HC+ME group acquired the best results. The extent of cartilage repair was correlated positively to bone formation activity at the injured site as verified by microCT and correlation analysis. Histology and immunofluorescence staining confirmed that bone remodeling activity was increased in HC and ME groups, and especially in HC+ME group. This bone formation process was accompanied by an increase in osteogenesis and chondrogenesis factors at the injury site which promoted cartilage repair. Conclusions: In a mouse model of osteochondral repair, HA-g-CS implant and moderate-intensity exercise may have a synergistic effect on improving osteochondral repair potentially through promotion of subchondral bone remodeling and generation of osteogenesis and chondrogenesis factors. Clinical Relevance: Combination of HA-g-CS implantation and moderate-intensity exercise may be considered potentially in clinic to promote osteochondral defect repair. Also, cartilage and subchondral bone forms a functional unit in an articular joint and subchondral bone may regulate cartilage repair by secreting growth factors in its remodeling process. However, a deeper insight into the exact role of HA-g-CS implantation and moderate-intensity exercise in promoting osteochondral repair in other animal models should be explored before they can be applied in clinic in the future.


Asunto(s)
Regeneración Ósea , Remodelación Ósea , Sustitutos de Huesos/uso terapéutico , Cartílago Articular/lesiones , Condicionamiento Físico Animal/fisiología , Animales , Regeneración Ósea/efectos de los fármacos , Regeneración Ósea/fisiología , Remodelación Ósea/efectos de los fármacos , Remodelación Ósea/fisiología , Sustitutos de Huesos/química , Sustitutos de Huesos/farmacología , Cartílago Articular/patología , Cartílago Articular/fisiopatología , Quitosano/química , Quitosano/farmacología , Condrogénesis/efectos de los fármacos , Durapatita/química , Durapatita/farmacología , Fracturas Óseas/patología , Fracturas Óseas/fisiopatología , Fracturas Óseas/terapia , Ratones , Ratones Endogámicos C57BL , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Ingeniería de Tejidos/métodos , Andamios del Tejido/química
19.
Angew Chem Int Ed Engl ; 60(16): 8694-8699, 2021 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-33491263

RESUMEN

With the interfacial jamming of nanoparticles (NPs), a load-bearing network of NPs forms as the areal density of NPs increases, converting the assembly from a liquid-like into a solid-like assembly. Unlike vitrification, the lineal packing of the NPs in the network is denser, while the remaining NPs can remain in a liquid-like state. It is a challenge to determine the point at which the assemblies jam, since both jamming and vitrification lead to a solid-like behavior of the assemblies. Herein, we show a real-time fluorescence imaging method to probe the evolution of the interfacial dynamics of NP surfactants at the water/oil interface using aggregation-induced emission (AIE) as a reporter for the transition of the assemblies into the jammed state. The AIEgens show typical fluorescence behavior at densities at which they can move and rotate. However, when aggregation of these fluorophores occurs, the smaller intermolecular separation distance arrests rotation, and a significant enhancement in the fluorescence intensity occurs.

20.
Angew Chem Int Ed Engl ; 60(6): 2871-2876, 2021 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-33111473

RESUMEN

Locking nonequilibrium shapes of liquids into targeted architectures by interfacial jamming of nanoparticles is an emerging area in material science. 5,10,15,20-tetrakis(4-sulfonatophenyl) porphyrin (H6 TPPS) shows three different aggregation states that present an absorption imaging platform to monitor the assembly and jamming of supramolecular polymer surfactants (SPSs) at the liquid/liquid interface. The interfacial interconversion of H6 TPPS, specifically H4 TPPS2- dissolved in water, from J- to an H-aggregation was induced by strong electrostatic interactions with amine-terminated polystyrene dissolved in toluene at the water/toluene interface. This resulted in color-tunable liquids due to interfacial jamming of the SPSs formed between H4 TPPS2- and amine-terminated polystyrene. However, the formed SPSs cannot lock in nonequilibrium shapes of liquids. In addition, a self-wrinkling behavior was observed when amphiphilic triblock copolymers of PS-block-poly(2-vinylpyridine)-block-poly(ethylene oxide) were used to interact with H4 TPPS2- . Subsequently, the SPSs formed can lock in nonequilibrium shapes of liquids.

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