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1.
Nat Commun ; 15(1): 5869, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997263

RESUMO

As a vital material utilized in energy storage capacitors, dielectric ceramics have widespread applications in high-power pulse devices. However, the development of dielectric ceramics with both high energy density and efficiency at high temperatures poses a significant challenge. In this study, we employ high-entropy strategy and band gap engineering to enhance the energy storage performance in tetragonal tungsten bronze-structured dielectric ceramics. The high-entropy strategy fosters cation disorder and disrupts long-range ordering, consequently regulating relaxation behavior. Simultaneously, the reduction in grain size, elevation of conductivity activation energy, and increase in band gap collectively bolster the breakdown electric strength. This cascade effect results in outstanding energy storage performance, ultimately achieving a recoverable energy density of 8.9 J cm-3 and an efficiency of 93% in Ba0.4Sr0.3Ca0.3Nb1.7Ta0.3O6 ceramics, which also exhibit superior temperature stability across a broad temperature range up to 180 °C and excellent cycling reliability up to 105. This research presents an effective method for designing tetragonal tungsten bronze dielectric ceramics with ultra-high comprehensive energy storage performance.

2.
Quant Imaging Med Surg ; 13(7): 4313-4324, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37456314

RESUMO

Background: Left atrial automated functional myocardial imaging (AFILA) is a new software program for analyzing the structure and function of the left atrium (LA). The present study sought to analyze the correlation between the LA function parameters as measured by AFILA echocardiography and the risk of cerebral ischemic stroke (CIS) in patients with non-valvular paroxysmal atrial fibrillation (NVPAF) to explore the diagnostic value of LA strain in patients with congestive heart failure, hypertension, age of ≥75 years (doubled), diabetes mellitus, stroke or transient ischemic attack (TIA) (doubled), age of 65-74 years, and sex category (female) (CHA2DS2-VASc) scores of <2. Methods: A total of 205 patients with NVPAF were included in the study and divided into the no-CIS group (154 patients) and the CIS group (51 patients). The baseline clinical data for the 2 groups were analyzed, and routine echocardiography examinations were performed. AFILA was used to evaluate the LA function of all the patients. Results: Compared to the no-CIS group, the LA emptying fraction and the LA reservoir strain were decreased, the LA contractile strain (S_CT) was increased, and the S_CT value changed from negative to positive in the CIS group, and the difference between the 2 groups were statistically significant (P<0.001). However, there were no significant differences in the volume at the onset of LA contraction, LA evacuation volume, LA minimum volume, LA maximum volume, and LA conduit strain between the 2 groups. The multifactorial regression analysis showed that age, hypertension, and the S_CT were independently associated risk factors for patients with CIS. After correcting for the clinical factors included in the CHA2DS2-VASc score, the S_CT was shown to predict to NVPAF with stroke [odds ratio (OR): 1.234, 95% confidence interval (CI): 1.101-1.383, P=0.000]. In addition, we included the CHA2DS2-VASc score (instead of age, diabetes, coronary artery disease, and hypertension) in a multiple regression analysis, and found that the S_CT was still significant (OR: 1.252, 95% CI: 1.118-1.402, P=0.000). The difference between the 2 groups in the CHA2DS2-VASc score for the S_CT was statistically significant, especially when the CHA2DS2-VASc score was <2. The S_CT equaled -4.5% was the cut-off value for the presence or absence of CIS in the NVPAF patients, with an area under the curve (AUC) of 0.866, sensitivity of 0.80, and specificity of 0.75 (P<0.0001). Conclusions: Comparison with LA volume parameter, measuring LA strain by AFILA provides a better index for the dynamic assessment of impaired LA function in patients with NVPAF combined with CIS, especially in those with a CHA2DS2-VASc score of <2. In addition, a LA S_CT of >-4.5% is a valuable cut-off for patients with NVPAF. The results of the current study may form the basis for a large prospective multicenter interventional study in which patients with impaired LA S_CT are randomized to receive oral anti-coagulant (OAC) therapy or no OAC therapy for the primary prevention of stroke.

3.
Quant Imaging Med Surg ; 13(5): 3241-3254, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37179944

RESUMO

Background: The treatment of advanced lung cancer has been revolutionized by immune checkpoint inhibitors (ICIs) in recent years, largely driven by programmed cell death-1 (PD-1) inhibitors. However, patients with lung cancer who are treated with PD-1 inhibitors are prone to immune-related adverse events (irAEs), especially cardiac adverse events. Noninvasive myocardial work is a novel technique used to assess left ventricular (LV) function, which can effectively predict myocardial damage. Here, noninvasive myocardial work was used to evaluate changes in LV systolic function during PD-1 inhibitor therapy and to assess ICIs-related cardiotoxicity. Methods: From September 2020 to June 2021, 52 patients with advanced lung cancer in the Second Affiliated Hospital of Nanchang University were prospectively enrolled. In total, 52 patients underwent PD-1 inhibitor therapy. The cardiac markers, noninvasive LV myocardial work, and conventional echocardiographic parameters were measured at pretherapy (T0) and posttreatment after the first (T1), second (T2), third (T3), and fourth (T4) cycles. Following this, the trends of the above parameters were analyzed using analysis of variance with repeated measures and the Friedman nonparametric test. Furthermore, the relationships between disease characteristics (tumor type, treatment regimen, cardiovascular risk factors, cardiovascular drugs, and irAEs) and noninvasive LV myocardial work parameters were assessed. Results: Throughout the follow-up, the cardiac markers and conventional echocardiographic parameters showed no significant changes. Based on the normal reference ranges, patients with PD-1 inhibitor therapy had increased values of LV global waste work (GWW) and decreased global work efficiency (GWE) that began at T2. Compared with T0, GWW increased from T1 to T4 (42%, 76%, 87%, and 87%, respectively), while global longitudinal strain (GLS), global work index (GWI), and global constructive work (GCW) decreased in varying degrees (P<0.001). Most of the disease characteristics had no effect on the LV myocardial work parameters; however, the numbers of irAEs were closely associated with GLS (P=0.034), GWW (P<0.001), and GWE (P<0.001). Patients with 2 or more irAEs had higher values of GWW and lower GLS and GWE. Conclusions: Noninvasive myocardial work can accurately reflect myocardial function and energy utilization in patients with lung cancer who are undergoing PD-1 inhibitor treatment and may thus benefit the management of patients with ICIs-related cardiotoxicity.

4.
ACS Appl Mater Interfaces ; 14(39): 44389-44397, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36153962

RESUMO

Dielectric capacitors possessing the inherent superiorities of high power density and ultrafast charge-discharge speed make their utilization in energy-storage devices extremely propitious, although the relatively low recoverable energy-storage density (Wrec) may impede their applications. In this work, unlike the mainstream approach of destroying long-range ferroelectric/antiferroelectric order and inducing relaxor properties to achieve a high Wrec value, we have selected end members with a high polarization gene to promote the polarization behavior of the typical relaxor Sr0.7Bi0.2TiO3. Therefore, an ultrahigh Wrec ∼ 8 J/cm3 and a superior efficiency (η) ∼ 91% are accomplished in the 0.98[0.56(Sr0.7Bi0.2)TiO3-0.44(Bi0.5Na0.5)TiO3]-0.02 Bi(Mg0.5Ti0.5)O3 sample. The achieved Wrec value is record high in Sr0.7Bi0.2TiO3-based systems as far as we know. The polarization-enhancement behavior can be explained by the phase field simulation results, phase content variance in X-ray diffraction Rietveld refinement, hardening trend in Raman spectroscopy, domain morphology, and local symmetry in transmission electron microscope analysis. Meanwhile, the ceramic possesses excellent thermal stability (ΔWrec < 12.7% and Δη < 10.4%, -50-200 °C), frequency (ΔWrec < 2.69% and Δη < 2.06%, 0.5-500 Hz), and fatigue-resistant stability (ΔWrec < 0.08% and Δη < 0.2%, up to 1 × 105 cycles). Accordingly, this work proposes a design idea to tailor the polarization behavior and energy-storage properties of typical relaxors.

5.
Quant Imaging Med Surg ; 12(6): 3170-3183, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35655829

RESUMO

Background: Systemic lupus erythematosus (SLE) is associated with a variety of cardiovascular diseases, even in the early stage of disease development. The purpose of this study was to quantitatively evaluate left ventricular (LV) systolic function in patients with SLE using a novel non-invasive pressure-strain loop (PSL) technique. Methods: This prospective case-control study included 132 patients with SLE and 99 normal controls, all of whom underwent traditional transthoracic echocardiography. The LV myocardial work was evaluated with the PSL technique based on speckle tracking and brachial artery blood pressure. The differences among groups were compared, and the correlations between myocardial work, laboratory data, and disease activity were analyzed in the SLE group. Results: Compared with the normal group, SLE patients had significantly higher global wasted work {GWW; SLE: 109 [82-150] mmHg%; controls: 66 [45-109] mmHg%; P<0.001} and impaired global work efficiency [GWE; SLE: 95% (94-97%); controls: 97% (96-98%); P<0.001]. Global work index (GWI) and global constructive work (GCW) did not show significant differences (P>0.05). Further subdivision analysis found that the increase of GWW and the damage of GWE were more obvious in SLE patients with high disease activity or severe diastolic dysfunction. Multivariate analysis revealed that increased erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), anti-phospholipid antibodies, peak strain dispersion, and SLE Disease Activity Index (SLEDAI) were independently associated with increased GWW (ß=0.189, 0.230, 0.444, 0.111, and 0.180, respectively; all P<0.05) and damaged GWE (ß=-0.184, -0.130, -0.468, -0.149, and -0.191, respectively; all P<0.05). Conclusions: The non-invasive PSL can quantitatively evaluate the LV systolic function in SLE patients. This technique may provide a new method for monitoring cardiac function in chronic diseases.

6.
ACS Biomater Sci Eng ; 8(6): 2307-2320, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35548973

RESUMO

Lymph node mapping for tumor micrometastasis is of great significance for the prevention, prognosis, and treatment of cancer. Currently, the traditional clinical detection methods (computed tomography, magnetic resonance imaging, or positron emission tomography/computed tomography) in clinical lymph node mapping still have some inherent disadvantages, which have prompted the development of various fluorescent probes for lymph node mapping. However, the conventional fluorescent probes such as indocyanine green or methylene blue in lymph node mapping are still accompanied by several problems such as impaired surgical field vision due to dye staining or less accumulation and shorter retention time in the lymph node. In a recent achievement, newly designed nanoparticles are prepared with novel properties that could be attractive for lymph node mapping. In this review, we will provide details on the progress of various nanoparticles for lymph node mapping and emphasize other multivariant properties in different nanoparticles, including strong tumor-targeting affinity and specificity, self-luminescence, and even with the function to kill metastatic cancer cells.


Assuntos
Micrometástase de Neoplasia , Biópsia de Linfonodo Sentinela , Corantes Fluorescentes , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Linfonodos/cirurgia , Metástase Linfática/patologia , Micrometástase de Neoplasia/patologia , Biópsia de Linfonodo Sentinela/métodos
7.
ACS Appl Mater Interfaces ; 13(21): 25143-25152, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34019365

RESUMO

Dielectric energy storage materials are becoming increasingly popular due to their potential superiority, for example, excellent pulse performance as well as good fatigue resistance. Although numerous studies have focused on lead-free dielectric materials which possess outstanding energy storage characteristics, the results are still not satisfying in terms of achieving both large discharging energy density (Wd) and high discharging efficiency (η) under low electric fields, which is crucial to be conducted in miniatured electronic components. Here, we adopt the strategy of domain engineering to develop sodium bismuth titanate (Bi0.5Na0.5TiO3)-based ceramics employed in the low-field situation. Remarkably, a large Wd of 2.86 J/cm3 and an ultrahigh η of 90.3% are concurrently obtained in 0.94(Bi0.5Na0.5)0.65(Ba0.3Sr0.7)0.35TiO3-0.06 Bi(Zn2/3Nb1/3)O3 system when the electric field is as low as 180 kV/cm. Additionally, the ceramic shows brilliant thermal endurance (20-160 °C) and frequency stability (0.1-100 Hz) with high Wd (>1.48 J/cm3) together with an ultra-high η (>90%). What's more, the ceramic displays a fast charge-discharge time (t0.9 = 109.2 ns). The piezoresponse force microscopy (PFM) results reveal that the introduced Bi(Zn2/3Nb1/3)O3 disrupts the microdomains of (Bi0.5Na0.5)0.65(Ba0.3Sr0.7)0.35TiO3 ceramics and promotes the formation of nanodomains, leading to enhanced energy storage properties. The current work may arouse interest in developing low-field high-performing dielectric capacitors for energy storage application.

8.
Jpn J Clin Oncol ; 40(5): 388-94, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20304779

RESUMO

OBJECTIVE: Neuroepithelial-transforming protein 1 is a member of the guanine nucleotide exchange factor family, a group of proteins which are known to activate and thereby regulate Rho family members. Deregulation of neuroepithelial-transforming protein 1 expression has been found in certain types of human tumors. To investigate its prognostic value in human gliomas, which is currently unknown, we examined the correlation between neuroepithelial-transforming protein 1 expression and prognosis in patients with gliomas. METHODS: Immunohistochemical staining was performed to detect neuroepithelial-transforming protein 1 expression patterns in the biopsies from 96 patients with primary gliomas. Kaplan-Meier survival and Cox's regression analyses were performed to evaluate the prognosis of patients. RESULTS: Immunohistochemical analysis with anti-neuroepithelial-transforming protein 1 antibody revealed that neuroepithelial-transforming protein 1 was significantly associated with the Karnofsky performance scale score and World Health Organization grades of patients with gliomas. Especially, the positive expression rates of neuroepithelial-transforming protein 1 were significantly higher in patients with higher grade (P = 0.001) and lower Karnofsky's performance scale score (P = 0.005). The median survival of patients with high neuroepithelial-transforming protein 1 expression was significantly shorter than that with low expression and without expression (316, 892 and 1180 days, respectively). Cox's multifactor analysis showed that the Karnofsky performance scale (P = 0.01), World Health Organization grade (P = 0.008) and neuroepithelial-transforming protein 1 (P = 0.006) were independent prognosis factors for human glioma. CONCLUSIONS: Taken together, our study indicates for the first time that neuroepithelial-transforming protein 1 status may be a highly sensitive marker for glioma prognosis and suggest that the expression patterns of neuroepithelial-transforming protein 1 might be a potent tool for predicting the clinical prognosis of glioma patients.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/patologia , Glioma/patologia , Proteínas Oncogênicas/metabolismo , Estudos de Casos e Controles , China , Feminino , Humanos , Imuno-Histoquímica , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Prognóstico , Análise de Sobrevida
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