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1.
J Orthop Translat ; 46: 18-32, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38774916

RESUMO

Background: Osteochondral regeneration has long been recognized as a complex and challenging project in the field of tissue engineering. In particular, reconstructing the osteochondral interface is crucial for determining the effectiveness of the repair. Although several artificial layered or gradient scaffolds have been developed recently to simulate the natural interface, the functions of this unique structure have still not been fully replicated. In this paper, we utilized laser micro-patterning technology (LMPT) to modify the natural osteochondral "plugs" for use as grafts and aimed to directly apply the functional interface unit to repair osteochondral defects in a goat model. Methods: For in vitro evaluations, the optimal combination of LMPT parameters was confirmed through mechanical testing, finite element analysis, and comparing decellularization efficiency. The structural and biological properties of the laser micro-patterned osteochondral implants (LMP-OI) were verified by measuring the permeability of the interface and assessing the recellularization processes. In the goat model for osteochondral regeneration, a conical frustum-shaped defect was specifically created in the weight-bearing area of femoral condyles using a customized trephine with a variable diameter. This unreported defect shape enabled the implant to properly self-fix as expected. Results: The micro-patterning with the suitable pore density and morphology increased the permeability of the LMP-OIs, accelerated decellularization, maintained mechanical stability, and provided two relative independent microenvironments for subsequent recellularization. The LMP-OIs with goat's autologous bone marrow stromal cells in the cartilage layer have securely integrated into the osteochondral defects. At 6 and 12 months after implantation, both imaging and histological assessments showed a significant improvement in the healing of the cartilage and subchondral bone. Conclusion: With the natural interface unit and zonal recellularization, the LMP-OI is an ideal scaffold to repair osteochondral defects especially in large animals. The translational potential of this article: These findings suggest that such a modified xenogeneic osteochondral implant could potentially be explored in clinical translation for treatment of osteochondral injuries. Furthermore, trimming a conical frustum shape to the defect region, especially for large-sized defects, may be an effective way to achieve self-fixing for the implant.

2.
J Agric Food Chem ; 72(12): 6236-6249, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38484389

RESUMO

Hypercholesterolemia poses a significant cardiovascular risk, particularly in postmenopausal women. The anti-hypercholesterolemic properties of Lactiplantibacillus plantarum ATCC8014 (LP) are well recognized; however, its improving symptoms on postmenopausal hypercholesterolemia and the possible mechanisms have yet to be elucidated. Here, we utilized female ApoE-deficient (ApoE-/-) mice undergoing bilateral ovariectomy, fed a high-fat diet, and administered 109 colony-forming units (CFU) of LP for 13 consecutive weeks. LP intervention reduces total cholesterol (TC) and triglyceride (TG) accumulation in the serum and liver and accelerates their fecal excretion, which is mainly accomplished by increasing the excretion of fecal secondary bile acids (BAs), thereby facilitating cholesterol conversion. Correlation analysis revealed that lithocholic acid (LCA) is an important regulator of postmenopausal lipid abnormalities. LP can reduce LCA accumulation in the liver and serum while enhancing its fecal excretion, accomplished by elevating the relative abundances of Allobaculum and Olsenella in the ileum. Our findings demonstrate that postmenopausal lipid dysfunction is accompanied by abnormalities in BA metabolism and dysbiosis of the intestinal microbiota. LP holds therapeutic potential for postmenopausal hypercholesterolemia. Its effectiveness in ameliorating lipid dysregulation is primarily achieved through reshaping the diversity and abundance of the intestinal microbiota to correct BA abnormalities.


Assuntos
Microbioma Gastrointestinal , Hipercolesterolemia , Lactobacillus plantarum , Humanos , Feminino , Camundongos , Animais , Hipercolesterolemia/metabolismo , Ácidos e Sais Biliares/metabolismo , Pós-Menopausa , Colesterol/metabolismo , Lactobacillus plantarum/metabolismo , Fígado/metabolismo , Apolipoproteínas E/metabolismo , Camundongos Endogâmicos C57BL , Dieta Hiperlipídica
3.
ACS Appl Mater Interfaces ; 16(4): 4999-5008, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38241705

RESUMO

Two-dimensional (2D) Ti3C2Tx MXene materials show great potential in electrochemical and flexible sensors due to their high electrical conductivity, good chemical stability, and special delaminated structure. However, their thermal properties were rarely studied, which remarkably affect the stability and safety of various devices. Here, we fabricated a suspended MXene drum resonator photothermally driven by a sinusoidally modulated laser, measured the thermal time constant by demodulating the thermomechanical motion, and then calculated the thermal conductivity and thermal diffusivity of the MXene film. Experiments show the thermal conductivity of the film increases from 3.10 to 3.58 W/m·K while the thermal diffusivity from 1.06 × 10-6 to 1.22 × 10-6 m2/s when temperature increases from 300 to 360 K. We also confirm the film thermal conductivity is mainly contributed by phonon transport rather than electron transport. Furthermore, the relationship between the mechanical and thermal properties of the MXene films was disclosed. The thermal conductivity decreases when film strain increases, caused by enhanced phonon scattering and softening of high-frequency phonons. The measurements provide a noninvasive method to analyze the thermal characteristics of suspended MXene films, which can be further extended to the thermal properties of other 2D materials.

4.
Small ; 20(4): e2306602, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37705120

RESUMO

The shell growth of large ZnSe/ZnS nanocrystals( is of great importance in the pursuit of pure-blue emitters for display applications, however, suffers from the challenges of spectral blue-shifts and reduced photoluminescence quantum yields. In this work, the ZnS shell growth on different-sized ZnSe cores is investigated. By controlling the reactivity of Zn and S precursors, the ZnS shell growth can be tuned from defect-related strain-released to defect-free strained mode, corresponding to the blue- and red-shifts of resultant nanocrystals respectively. The shape of strain-released ZnSe/ZnS nanocrystals can be kept nearly spherical during the shell growth, while the shape of strained nanocrystals evolutes from spherical into island-like after the critical thickness. Furthermore, the strain between ZnSe core and ZnS shell can convert the band alignment from type-I into type-II core/shell structure, resulting in red-shifts and improved quantum yield. By correlating the strain effects with interfacial defects, a strain-released shell growth model is proposed to obtain large ZnSe/ZnS nanocrystals with isotropic shell morphology.

5.
World Neurosurg ; 183: 172-179, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38101541

RESUMO

BACKGROUND: In addition to evaluate the morphologic characteristics of intracranial aneurysms, the dimension of the aneurysm is an important parameter for selecting treatment strategies, determining follow-up period, and predicting the risk of rupture. High-resolution vessel wall imaging has an increasingly dominant role in measuring aneurysm size and assessing the risk of rupture accurately. The size of saccular intracranial aneurysm may play an important role as a predictor of the rupture risk. With the rapid improvement in radiological techniques, different noninvasive imaging methods have respective characteristics in saccular intracranial aneurysms (sIA) measurement and morphologic description. Although most studies believe that the larger the aneurysm, the higher the risk of rupture, there is still a synergistic effect of multiple factors (such as location, morphology, history of aneurysmal subarachnoid hemorrhage, and even patient factors) to explain the rupture of small aneurysms. METHODS: A literature search was performed of intracranial aneurysm size and risk of rupture. RESULTS: The specificity and sensitivity of different imaging methods for evaluating intracranial aneurysms varied based on sizes. Rupture risk of aneurysms was associated with multiple factors. A comprehensive assessment that considered aneurysm size in conjunction with other relevant factors would be helpful in guiding options of management. CONCLUSIONS: Accurate measurement of the dimension of sIA is an important basis in the selection of appropriate treatment including intravascular intervention or surgical clipping, as well as for determining the follow-up cycles for conservative or postoperative treatment. A uniform definition of sIA size is recommended to facilitate the integration of similar studies and to accomplish rapid and effective screening of cases in sIA treatment.


Assuntos
Aneurisma Roto , Aneurisma Intracraniano , Hemorragia Subaracnóidea , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/cirurgia , Hemorragia Subaracnóidea/diagnóstico por imagem , Diagnóstico por Imagem , Fatores de Risco
7.
Pharmaceutics ; 15(7)2023 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-37514054

RESUMO

Cancer immunotherapy is an innovative treatment strategy to enhance the ability of the immune system to recognize and eliminate cancer cells. However, dose limitations, low response rates, and adverse immune events pose significant challenges. To address these limitations, gold nanoparticles (AuNPs) have been explored as immunotherapeutic drug carriers owing to their stability, surface versatility, and excellent optical properties. This review provides an overview of the advanced synthesis routes for AuNPs and their utilization as drug carriers to improve precision therapies. The review also emphasises various aspects of AuNP-based immunotherapy, including drug loading, targeting strategies, and drug release mechanisms. The application of AuNPs combined with cancer immunotherapy and their therapeutic efficacy are briefly discussed. Overall, we aimed to provide a recent understanding of the advances, challenges, and prospects of AuNPs for anticancer applications.

8.
Dalton Trans ; 52(29): 10155-10164, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37432053

RESUMO

At present, most fluorescent materials that can be used for optical temperature measurement exhibit poor thermochromic performance, which limits their applications. In this study, the phosphor Ba3In(PO4)3:Er/Yb was synthesized with a high doping concentration of Yb3+, and it emitted composition- and temperature-induced wide color gamut up-conversion luminescence from red to green. Four modes of fluorescence thermometry can be realized in the temperature range of 303-603 K, which is based on the ratio of fluorescence intensity between thermally coupled energy levels and non-thermally coupled energy levels, color coordinate shift, and fluorescence decay lifetime, respectively. The highest Sr value obtained was 0.977% K-1. Taking advantage of the fact that temperature can significantly change the luminous color of the phosphor Ba3In(PO4)3:0.02Er3+/0.05Yb3+, we demonstrated 'temperature mapping' on a smooth metal surface with multiple optical encryptions. These results indicate that the Ba3In(PO4)3:Er/Yb phosphor is an excellent fluorescent material for thermal imaging and has great application potential in temperature visualization measurement and optical encryption.

9.
Interv Neuroradiol ; : 15910199231182850, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37309134

RESUMO

BACKGROUND: Clot analogs are essential in animal and in vitro experiments on mechanical thrombectomy devices for treating acute ischemic stroke. Clot analogs should be capable of reproducing a variety of arterial clots observed in clinical practice in terms of histological composition and mechanical properties. METHODS: Bovine blood with added thrombin was stirred in a beaker so that clots could be formed under the condition of dynamic vortical flow. Static clots were also prepared without stirring, and the properties of the static clots and dynamic clots were compared. Histological and scanning electron microscopy experiments were performed. Compression and relaxation tests were performed to evaluate the mechanical properties of the two types of clots. Thromboembolism and thrombectomy tests were conducted in an in vitro circulation model. RESULTS: Compared to the static clots, the dynamic clots prepared under vortical flow displayed a higher fibrin content, and their fibrin network was denser and sturdier than that of the static clots. The stiffness of the dynamic clots was significantly higher than that of the static clots. The stress of both types of clots could decay quickly under large sustained strain. The static clots could break at the bifurcation in the vascular model, while the dynamic clots could be firmly stuck in the vascular model. CONCLUSIONS: Dynamic clots generated in dynamic vortical flow differ significantly from static clots in terms of their composition and mechanical properties, which may be beneficial information for preclinical research on mechanical thrombectomy devices.

10.
ACS Omega ; 8(17): 15698-15707, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37151565

RESUMO

Long-wavelength broadband near-infrared (NIR) phosphors have attracted considerable interest in the fields of medical cosmetology and organic detection because of their special emission band. Herein, Ca2GeO4(CGO): Cr4+ NIR phosphor, presenting a broadband emission with longer wavelength ranging from 1100 to 1600 nm, has been synthesized. Further, the luminescence intensity and quantum efficiency of Cr4+ could be obviously improved via the energy transfer from Eu3+ to Cr4+. The energy transfer is dominated by the dipole-dipole mechanism, which can be inferred from the spectra and the decay curves. Furthermore, in order to evaluate the potential application, an NIR phosphor-converted light-emitting diode (pc-LED) based on blue chip has been prepared. Consequently, CGO: Eu3+, Cr4+ exhibits proper output power and wider half-width than the NIR LED chip, indicating its great prospect for long-wavelength NIR pc-LED applications.

11.
Materials (Basel) ; 16(8)2023 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37109981

RESUMO

Near-infrared (NIR) light has attracted considerable attention in diverse applications, such as food testing, security monitoring, and modern agriculture. Herein, the advanced applications of NIR light, as well as various devices to realize NIR light, have been described. Among the diverse NIR light source devices, the NIR phosphor-converted light-emitting diode (pc-LED), serving as a new-generation NIR light source, has obtained attention due to its wavelength-tunable behavior and low-cost. As one of the key materials of the NIR pc-LED, a series of NIR phosphors have been summarized depending on the type of luminescence center. Meanwhile, the characteristic transitions and luminescence properties of the above phosphors are illustrated in detail. In addition, the status quo of NIR pc-LEDs, as well as the potential problems and future developments of NIR phosphors and applications have also been discussed.

12.
J Bioeth Inq ; 20(1): 19-20, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36508142

Assuntos
Pandemias , Humanos
14.
Interv Neuroradiol ; 29(6): 759-767, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35971288

RESUMO

Mechanical thrombectomy has become an important method for the treatment of acute ischemic stroke for large vessel occlusions. The current hotspots of mechanical thrombectomy are optimizing the treatment methods, improving the recanalization rate and reducing complications. The in vitro model has become a common and convenient method for mechanical thrombectomy research. This review summarizes the in vitro model in the following aspects: the preparation of clot analogues; the experimental platform; the application of the in vitro model in the testing of thrombectomy devices; and the advantages, limitations and future trends of the in vitro experimental model. This review describes the characteristics and applications of the in vitro experimental model with the hope that the in vitro experimental model will be further improved and play a more effective role in the study of mechanical thrombectomy.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , AVC Isquêmico/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Resultado do Tratamento , Stents/efeitos adversos , Trombectomia/métodos , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia
15.
Front Psychol ; 13: 870753, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35967707

RESUMO

After experiencing the COVID-19 pandemic, the status and mechanisms of leadership, and the challenges for medical workers in terms of family-work conflicts, have caused widespread concern. In the post-pandemic era, based on role theory and the stressor-detachment model, this paper seeks to break the "black box" of negative effects that can be caused by leadership, research the mechanism and boundary conditions of those negative effects, and explore factors to reduce those negative effects. We recruited 1,010 Chinese medical workers fighting COVID-19 on the frontline. Our study results showed that there was a significant negative correlation between empowering leadership and work-family conflict, and this relationship was completely mediated by role stress, while psychological detachment moderated the relationship between role stress and work-family conflict. Moreover, psychological detachment moderated the mediating effect of empowering leadership on work-family conflict through role stress. Therefore, higher levels of psychological detachment were less conducive to medical workers' family-work conflict. This study has important theoretical significance and practical value for revealing the negative effects and mechanisms of empowering leadership and for medical workers to better deal with work-family relations.

16.
Front Aging Neurosci ; 14: 868777, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35912072

RESUMO

Objective: To investigate the relations of serum total homocysteine (tHcy) with cerebral small vessel disease (CSVD) and cognitive function and evaluate whether CSVD mediates the effect of serum tHcy on cognitive function. Methods: A total of 1,033 consecutive eligible participants who received serum tHcy, brain magnetic resonance imaging (MRI), and neuropsychological assessment were included in this retrospective study. White matter hyperintensity, lacune, cerebral microbleed, and enlarged perivascular space were evaluated based on brain MRI. We used multivariate binary logistic regression analysis, multivariate ordinal logistic regression analysis, and mediation analyses to assess the relations of serum tHcy with CSVD and cognitive function. Results: Serum tHcy levels were higher in patients with cognitive impairment than those with no cognitive impairment. Logistic regression analyses showed elevated serum tHcy was associated with cognitive impairment [odds ratio (OR): 10.475; 95% confidence interval (CI): 4.522 to 24.264; p < 0.001] and a higher CSVD burden score (OR: 17.151; 95% CI: 8.785 to 33.921; p < 0.001) after adjusting potential confounders. Compared with the lowest tHcy quartile, the multivariable-adjusted OR of the highest quartile was 4.851 (95% CI: 3.152 to 7.466; p for the trend < 0.001) for cognitive impairment, 3.862 (95% CI: 2.467 to 6.047; p for the trend < 0.001) for a severe CSVD burden score. Mediation analyses showed significant moderating effects (9.3-23.6%) by different imaging markers of CSVD on the association between higher serum tHcy levels and cognitive impairment. Conclusion: Elevated serum tHcy is associated with cognitive impairment and the development of CSVD. A proportion of the association between elevated serum tHcy and cognitive impairment may be attributed to the presence of different imaging markers of CSVD, especially the severe CSVD burden score.

17.
Diabetes Metab Syndr Obes ; 15: 1985-1994, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814027

RESUMO

Objective: Type 2 diabetes mellitus (T2DM) is associated with cognitive impairment, but the underlying cerebral small vessel disease (CSVD)-related structural brain correlates are unclear. The aim of this study was to investigate the relationship between various imaging markers of CSVD and mild cognitive impairment (MCI) in patients with T2DM. Methods: A total of 228 eligible participants with T2DM who were divided into MCI group and normal cognitive group based on neuropsychological assessment were enrolled in this retrospective study. White matter hyperintensity (WMH), lacunes, cerebral microbleeds (CMBs) and enlarged perivascular spaces (EPVS) were evaluated based on brain magnetic resonance imaging (MRI). The total CSVD burden score was calculated by combining the above four markers of CSVD. Binary logistic regression analysis was used to evaluate the relationship between different imaging markers of CSVD and MCI in patients with T2DM. Kruskal-Wallis test and Jonckheere-Terpstra test were used to compare mean MoCA scores among individuals with varying CSVD markers. Results: In the multivariate binary logistic regression analyses, moderate or severe total CSVD burden (OR: 3.29, 95% CI: 1.63-7.38, P=0.004; OR: 10.97, 95% CI: 4.94-24.34, P<0.001, respectively), moderate dWMH (OR: 3.26, 95% CI: 1.43-7.41, P=0.005), extensive lacunes (OR: 4.97, 95% CI: 1.79-13.81, P=0.002), and moderate BG-EPVS (OR: 3.84, 95% CI: 1.81-8.13, P<0.001) were associated with MCI in patients with T2DM related to MCI after adjusting for potential confounders. There was a trend for significant decrease in MoCA scores with increase severity of dWMH, pWMH, lacunes, BG-EPVS, deep CMBs, or total CSVD burden (P for trend <0.05). Conclusion: Different imaging markers of CSVD, particularly total CSVD burden, were associated with an increased risk of MCI and decline in MoCA scores in patients with T2DM. These findings may provide clues for future studies to explore early diagnostic imaging markers of cognitive impairment in relation to T2DM.

18.
Int Microbiol ; 25(3): 541-550, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35175436

RESUMO

Low pH eliminated the jarosite accumulation and improved the interfacial reaction rate during the bioleaching process. However, high acidity tends to make environments less hospitable, even for organisms that live in extreme places, so a great challenge existed for bioleaching at low pH conditions. This study demonstrated that the adaption and bioleaching ability of Leptospirillum ferriphilum could be improved after the long-term adaptive evolution of the community under acidity conditions. It was found that the acidity-adapted strain showed robust ferrous iron oxidation activity in wider pH, high concentration of ferrous iron, and lower temperature. Although the enhancement for heavy metal tolerance was limited, the resistance for MgSO4, Na2SO4, and organic matter was stimulative. More importantly, both pyrite and printed circuit board bioleaching revealed the higher bioleaching ability of the acid-resistant strain. These adaptation and bioleaching details provided an available approach for the improvement of bioleaching techniques.


Assuntos
Bactérias , Ferro , Adaptação Fisiológica , Oxirredução
19.
Inorg Chem ; 61(3): 1805-1815, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35021010

RESUMO

Developing broadband cyan-emitting phosphors is an essential issue to achieve high-quality full-spectrum phosphor-converted white light-emitting diodes. Multisite cation regulation to modify the photoluminescence spectrum is a valid way to achieve broadband emission for phosphors. The Ba9Lu2Si6O24 lattice with various cation sites for activator ions is a preferred host for broadband emitting phosphors. The preferential crystallographic sites of Eu2+ in the Ba9Lu2Si6O24 lattice are identified based on the crystal field theory, crystal structure, and bond indices (such as NAC and SBOs) of the cations. Sr substitution in Ba9Lu2Si6O24/Eu2+ phosphor affects the location of Eu2+ activator ions, which is investigated via the first-principles density functional theory calculations, Rietveld refinement, and luminescence decay curves, and results in the modification of luminescence properties and thermal stability. The Sr-substituted (Ba0.8Sr0.2)9Lu2Si6O24/Eu2+ sample exhibits a broadband emission spectrum peaked at 471 and 518 nm with a large full width half maximum of 139 nm, covering blue-cyan-green regions, which can be an excellent candidate as broadband cyan-emitting phosphors for high-quality full-spectrum wLEDs.

20.
J Int Med Res ; 50(1): 3000605211069485, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34994238

RESUMO

Poland syndrome is a rare congenital developmental deformity characterized by unilateral agenesis or hypoplasia of thoracic wall soft tissue. We report two adult cases of Poland syndrome detected by computed tomography (CT) images. CT images of the two cases depicted an asymmetric chest wall with the absence of a breast and agenesis of the pectoralis muscles. A physical examination of case 1 showed a thin right chest wall with depression of the right nipple region. Hand deformities were also observed, including brachydactyly and syndactyly. In case 2, hand deformities were not found in a physical examination. Using multi-planar reconstruction, the size, position, origin, and termination of bilateral pectoral muscles could be compared symmetrically. For patients with Poland syndrome, a timely diagnosis and treatment are important. The use of chest CT in clinical practice could play an important role in the early diagnosis and treatment of Poland syndrome.


Assuntos
Síndrome de Poland , Parede Torácica , Adulto , Humanos , Mamilos , Músculos Peitorais/diagnóstico por imagem , Síndrome de Poland/diagnóstico por imagem , Parede Torácica/diagnóstico por imagem , Tomografia Computadorizada por Raios X
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