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1.
J Am Chem Soc ; 146(25): 17355-17364, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38870542

RESUMO

GeSe, an analogue of SnSe, shows promise in exhibiting exceptional thermoelectric performance in the Pnma phase. The constraints on its dopability, however, pose challenges in attaining optimal carrier concentrations and improving ZT values. This study demonstrates a crystal structure evolution strategy for achieving highly doped samples and promising ZTs in GeSe via LiBiTe2 alloying. A rhombohedral phase (R3m) can be stabilized in the GeSe-LiBiTe2 system, further evolving into a cubic (Fm3̅m) phase with a rising temperature. The band structures of GeSe-LiBiTe2 in the rhombohedral and cubic phases feature a similar multiple-valley energy-converged valence band of L and Σ bands. The observed high carrier concentration (∼1020 cm-3) reflects the effective convergence of these bands, enabling a high density-of-states effective mass and an enhanced power factor. Moreover, a very low lattice thermal conductivity of 0.6-0.5 W m-1 K-1 from 300 to 723 K is achieved in 0.9GeSe-0.1LiBiTe2, approaching the amorphous limit value. This remarkably low lattice thermal conductivity is related to phonon scattering from point defects, planar vacancies, and ferroelectric instability-induced low-energy Einstein oscillators. Finally, a maximum ZT value of 1.1 to 1.3 at 723 K is obtained, with a high average ZT value of over 0.8 (400-723 K) in 0.9GeSe-0.1LiBiTe2 samples. This study establishes a viable route for tailoring crystal structures to significantly improve the performance of GeSe-related compounds.

2.
Cardiovasc Diabetol ; 23(1): 3, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172813

RESUMO

BACKGROUND: The triglyceride-glucose (TyG) index has been proposed as a surrogate marker of insulin resistance. However, the relationship between the TyG index and central blood pressure (BP), has not been well studied in adults. METHODS: A total of 715 Chinese adult participants were enrolled in this study. Anthropometric and BP were assessed. The TyG index was calculated as ln[fasting triglycerides(mg/dL) × fasting glucose(mg/dL)/2]. Central BP was measured using SphygmoCor system. RESULTS: The participants were stratified into three groups based on the TyG index, and significant differences were observed in metabolic and cardiovascular parameters and the prevalence of hypertension among the groups. Both brachial (ß = 1.38, P = 0.0310; group highest vs. lowest, ß = 2.66, P = 0.0084) and aortic (ß = 2.38, P = 0.0002; group highest vs. lowest, ß = 3.96, P = 0.0001) diastolic BP were significantly and independently associated with the TyG index and increasing TyG index tertile. However, there was no independent association between the TyG index and systolic BP. A one-unit increase in the TyG index was associated with a 46% higher risk of hypertension (P = 0.0121), and compared with the lowest group, participants in the highest group had a 95% higher risk of hypertension (P = 0.0057). CONCLUSIONS: Our study demonstrates a significant and independent association between the TyG index and both brachial and aortic diastolic BP in Chinese adults. Furthermore, the TyG index was found to be an independent predictor of hypertension.


Assuntos
Hipertensão , Resistência à Insulina , Adulto , Humanos , Glucose/metabolismo , Glicemia/metabolismo , Triglicerídeos , Pressão Sanguínea , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Biomarcadores , China/epidemiologia , Fatores de Risco
3.
Tob Control ; 33(e1): e11-e17, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-36813571

RESUMO

BACKGROUND: Singapore has completely banned e-cigarettes and the government's cautious stance against vaping has been consistent. Despite this, vaping appears to have gained popularity in Singapore, especially among younger people. With the heavy marketing of vaping products on social media, it is possible that such marketing, due to its cross-border nature, is reaching younger Singaporeans and driving changes in vaping-related perceptions or behaviours. This study examines their exposure to vaping-related content on social media, and whether such exposure is associated with more positive perceptions of vaping or e-cigarette ever use. METHODS: Analysis of cross-sectional survey data of 550 adult (age 21-40 years) Singaporeans recruited via convenience methods in May 2022, using descriptive statistics, bivariate analyses, and multiple linear and logistic regression models. RESULTS: 16.9% of participants reported they had ever used e-cigarettes. 18.5% of those who used social media recalled seeing vaping-related content on a social media platform in the past 6 months, mostly from influencers or friends, and on Instagram, Facebook, TikTok and/or YouTube. Reporting exposure to such content was not associated with e-cigarette ever use. It was associated with having a more positive overall perception of vaping (ß=1.47; 95% CI: 0.17 to 2.78), although no significant difference was observed when examining only health-related perceptions. CONCLUSION: Even in a heavily regulated environment such as Singapore's, people appear to be exposed to vaping-related content on social media platforms and this exposure is, in turn, associated with more positive perceptions of vaping, but not e-cigarette ever use.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Mídias Sociais , População do Sudeste Asiático , Vaping , Adulto , Humanos , Adulto Jovem , Estudos Transversais , Exposição à Mídia
4.
J Clin Nurs ; 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38356194

RESUMO

AIMS AND OBJECTIVES: To explore the relationships among post-stroke fatigue, hope and discharge readiness in stroke patients, and to determine whether hope mediates the relationship between post-stroke fatigue and discharge readiness. BACKGROUND: In stroke patients, inadequate discharge readiness has been found to correlate with higher readmission and mortality rates. Although previous qualitative studies have confirmed the impact of fatigue on discharge readiness, few studies explore the impact of post-stroke fatigue and hope on discharge readiness of stroke patients. Consequently, the current research on this relationship and its underlying mechanisms is still quite limited. DESIGN: Cross-sectional study. METHODS: Data were collected from 340 stroke patients. The research tools included demographic and disease characteristics, Discharge Readiness Assessment Scale for Stroke, Neurological Fatigue Index for Stroke and Herth Hope Index. The STROBE checklist was used to guide the presentation of this study. RESULTS: Discharge readiness was negatively correlated with post-stroke fatigue and positively correlated with hope. Additionally, post-stroke fatigue was negatively correlated with hope. Post-stroke fatigue had a direct negative effect on discharge readiness, and it can also generate indirect effects through hope. Hope was the partial mediator between post-stroke fatigue and discharge readiness, explaining 55.8% of the total effect. CONCLUSION: Discharge readiness of this population can be improved by reducing post-stroke fatigue and increasing hope. Therefore, effective management of post-stroke fatigue and hope will help improve discharge readiness. RELEVANCE TO CLINICAL PRACTICE: It is recommended that nursing staff should monitor the occurrence and development of post-stroke fatigue in stroke patients, dynamically evaluate the patient's level of hope, and pay attention to the important role of positive psychological qualities in the outcome of discharge. If medical staff can formulate corresponding intervention measures based on the influence path of discharge readiness, then the discharge readiness of stroke patients can be improved.

5.
J Am Chem Soc ; 145(3): 1988-1996, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36648753

RESUMO

GeMnTe2 adopts a cubic rock salt structure and is a promising mid-temperature thermoelectric material. The pair distribution function analysis of neutron total scattering data, however, indicates that GeMnTe2 is locally distorted from the ideal rock salt structure with Ge2+ cations being discordant and displaced ∼0.3 Å off the octahedron center. By alloying GeMnTe2 with SbTe, the carrier concentration can be tuned in GeMnTe2-x%SbTe (x = 15.1), leading to converged multiple broad valence bands and a high Seebeck coefficient of >200 µV K-1 from 300 to 823 K. The system exhibits a large density-of-state effective mass of >10 me and a high weighted mobility of 80 cm2 V-1 s-1, leading to a power factor of 15 µWcm-1 K-2 at 823 K. The composition GeMnTe2-15.1%SbTe exhibits very low lattice thermal conductivity of ∼0.5 Wm-1 K-1 at 823 K, attributed to the combination of off-centering cations in the rock salt structure, Ge/Mn positional disorder, dislocations, and abundant Ge-rich and Mn-rich nanoparticles. A ZT value of ∼1.5 can be achieved for GeMnTe2-15.1%SbTe with a ZTave of 0.96 in the temperature range of 400-823 K.

6.
Inorg Chem ; 62(43): 17905-17912, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37843461

RESUMO

Thermoelectric sulfide materials are of particular interest due to the earth-abundant and cost-effective nature of sulfur. Here, we report a new n-type degenerate semiconductor sulfide, AgBiPbS3, which adopts a Fm3̅m structure with a narrow band gap of ∼0.32 eV. Despite the homogeneous distribution of elements at the scale of micrometer, Ag2S nanoprecipitates with dimensions of several nanometers were detected throughout the matrix. AgBiPbS3 exhibits a low room-temperature lattice thermal conductivity of 0.88 W m-1 K-1, owing to the intrinsic low lattice thermal conductivity of Ag2S and the effective scattering of phonons at nanoprecipitate boundaries. Moreover, compared to AgBiS2, AgBiPbS3 demonstrates a significantly improved weighted mobility of >16 cm2 V-1 s-1 at 300 K, leading to an enhanced PF of 1.6 µW cm-1 K-2 at 300 K. The superior electrical transport in AgBiPbS3 can be attributed to the high valley degeneracy of the L point (the conduction band minimum), which is contributed by the Pb s and Pb p orbitals. Further, Ga doping is found to be effective in modulating the Fermi levels of AgBiPbS3, leading to further enhancement of PF with a PFave of 2.7 µW cm-1 K-2 in the temperature range of 300-823 K. Consequently, a relatively high ZTave of 0.22 and a peak ZT of ∼0.4 at 823 K have been achieved in 3% Ga-doped AgBiPbS3, highlighting the potential of AgBiPbS3 as an n-type thermoelectric sulfide.

7.
J Ultrasound Med ; 42(5): 1015-1022, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36217560

RESUMO

OBJECTIVE: To evaluate the location and characterization value of contrast-enhanced ultrasound (CEUS) in the detection of sentinel lymph nodes (SLNs) in malignant melanoma. METHODS: SLNs and the lymph node network were tracked by subcutaneous injection of ultrasonic contrast agent around the tumor and preoperative localization, and qualitative analyses were performed. The SLNs were also detected by the intraoperative subcutaneous injection of carbon nanoparticles, and the findings were compared with lymph nodes located by CEUS. The accuracy of the preoperative lymph node identification was evaluated by the results of postoperative pathology, which served as the gold standard of detection. RESULTS: In 47 patients with malignant melanoma, the mean number of SLNs detected by CEUS was 1.72 ± 0.10, while that by carbon nanoparticle administration it was 1.79 ± 1.07 (P = .371 > .05). Seven cases of lymph node metastasis were detected by CEUS, with a sensitivity of 70.0%, specificity of 97.3%, positive predictive value of 87.5%, negative predictive value of 92.3%, and accuracy of 91.5%. There was high consistency between the findings of CEUS and pathology in differentiating benign and malignant lymph nodes (kappa = 0.726, χ2  = 25.243, P < .001). CONCLUSIONS: CEUS can localize and differentiate SLNs in malignant melanoma, and thus, may potentially guide clinical treatment in the future.


Assuntos
Melanoma , Linfonodo Sentinela , Humanos , Linfonodo Sentinela/diagnóstico por imagem , Linfonodo Sentinela/patologia , Biópsia de Linfonodo Sentinela/métodos , Ultrassonografia/métodos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Meios de Contraste , Melanoma/diagnóstico por imagem , Melanoma Maligno Cutâneo
8.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(3): 302-307, 2023 Mar 15.
Artigo em Zh | MEDLINE | ID: mdl-36946167

RESUMO

OBJECTIVES: To study the clinical features of children with autoimmune encephalitis (AE) secondary to epidemic encephalitis B (EEB). METHODS: A retrospective analysis was performed on the medical data of five children with EEB with "bipolar course" who were treated in Children's Hospital Affiliated to Zhengzhou University from January 2020 to June 2022. RESULTS: Among the five children, there were three boys and two girls, with a median age of onset of 7 years (range 3 years 9 months to 12 years) and a median time of 32 (range 25-37) days from the onset of EEB to the appearance of AE symptoms. The main symptoms in the AE stage included dyskinesia (5/5), low-grade fever (4/5), mental and behavioral disorders (4/5), convulsion (2/5), severe disturbance of consciousness (2/5), and limb weakness (1/5). Compared with the results of cranial MRI in the acute phase of EEB, the lesions were enlarged in 3 children and unchanged in 2 children showed on cranial MRI in the AE stage. In the AE stage, four children were positive for anti-N-methyl-D-aspartate receptor antibody (one was also positive for anti-γ-aminobutyric acid type B receptor antibody), and one was negative for all AE antibodies. All five children in the AE stage responded to immunotherapy and were followed up for 3 months, among whom one almost recovered and four still had neurological dysfunction. CONCLUSIONS: EEB can induce AE, with anti-N-methyl-D-aspartate receptor encephalitis as the most common disease. The symptoms in the AE stage are similar to those of classical anti-N-methyl-D-aspartate receptor encephalitis. Immunotherapy is effective for children with AE secondary to EEB, and the prognosis might be related to neurological dysfunction in the acute phase of EEB.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato , Encefalite por Arbovirus , Doença de Hashimoto , Masculino , Feminino , Humanos , Criança , Recém-Nascido , Estudos Retrospectivos , Doença de Hashimoto/complicações , Doença de Hashimoto/epidemiologia , Doença de Hashimoto/terapia
9.
Ann Rheum Dis ; 81(4): 544-555, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34853001

RESUMO

OBJECTIVES: Dysregulated chondrocyte metabolism is closely associated with the pathogenesis of osteoarthritis (OA). Suppressing chondrocyte catabolism to restore cartilage homeostasis has been extensively explored, whereas far less effort has been invested toward enhancing chondrocyte anabolism. This study aimed to repurpose clinically approved drugs as potential stimulators of chondrocyte anabolism in treating OA. METHODS: Screening of a Food and Drug Administration-approved drug library; Assays for examining the chondroprotective effects of digoxin in vitro; Assays for defining the therapeutic effects of digoxin using a surgically-induced OA model; A propensity-score matched cohort study using The Health Improvement Network to examine the relationship between digoxin use and the risk of joint OA-associated replacement among patients with atrial fibrillation; identification and characterisation of the binding of digoxin to low-density lipoprotein receptor-related protein 4 (LRP4); various assays, including use of CRISPR-Cas9 genome editing to delete LRP4 in human chondrocytes, for examining the dependence on LRP4 of digoxin regulation of chondrocytes. RESULTS: Serial screenings led to the identification of ouabain and digoxin as stimulators of chondrocyte differentiation and anabolism. Ouabain and digoxin protected against OA and relieved OA-associated pain. The cohort study of 56 794 patients revealed that digoxin use was associated with reduced risk of OA-associated joint replacement. LRP4 was isolated as a novel target of digoxin, and deletion of LRP4 abolished digoxin's regulations of chondrocytes. CONCLUSIONS: These findings not only provide new insights into the understanding of digoxin's chondroprotective action and underlying mechanisms, but also present new evidence for repurposing digoxin for OA.


Assuntos
Cartilagem Articular , Digoxina , Proteínas Relacionadas a Receptor de LDL , Osteoartrite , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Estudos de Coortes , Digoxina/farmacologia , Reposicionamento de Medicamentos , Humanos , Proteínas Relacionadas a Receptor de LDL/antagonistas & inibidores , Osteoartrite/tratamento farmacológico , Osteoartrite/patologia , Ouabaína/farmacologia
10.
Inorg Chem ; 61(17): 6451-6458, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35438965

RESUMO

Herein, we have successfully synthesized binary Ag2Se, composite Ag0:Ag2Se, and ternary Cu+:Ag2Se through an ambient aqueous-solution-based approach in a one-pot reaction at room temperature and atmospheric pressure without involving high-temperature heating, multiple-processes treatment, and organic solvents/surfactants. Effective controllability over phases and compositions/components are demonstrated with feasibility for large-scale production through an exquisite alteration in reaction parameters especially pH for enhancing and understanding thermoelectric properties. Thermoelectric ZT reaches 0.8-1.1 at near-room-temperature for n-type Ag2Se and Cu+ doping further improves to 0.9-1.2 over a temperature range of 300-393 K, which is the largest compared to that reported by wet chemistry methods. This improvement is related to the enhanced electrical conductivity and the suppressed thermal conductivity due to the incorporation of Cu+ into the lattice of Ag2Se at very low concentrations (x%Cu+:Ag2Se, x = 1.0, 1.5, and 2.0).

11.
Phys Chem Chem Phys ; 24(22): 13773-13783, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35612322

RESUMO

A supramolecular polymer was developed through the encapsulation of polypyrrole by cucurbit[6]uril (PPy@Q[6]), which was employed as the electrode material to improve the capacitor ability of conductive polypyrrole. In the optimized ratio of 2 : 1 (CPPy : CQ[6]), the capacitor properties of the supramolecular material were evaluated, and a high specific capacitance of 414 F g-1 at 10 mV s-1 was obtained, which was 3.1 times higher than that of pure polypyrrole (132 F g-1). A comprehensive analysis suggested that the capacitance performances should be relevant to the component, surface area, and pore volume of the materials. The addition of 0.4 M Fe2(SO4)3 into the electrolyte provided a surprising specific capacitance of 3530 F g-1 on the cucurbituril-encapsulated polypyrrole electrode material, with a high energy density of 707 W h kg-1 at a power density of 32 000 W kg-1 and a current density of 8 A g-1. The 81.6% capacitance retention maintained after 1000 cycles revealed the acceptable cycling capacity of the proposed supramolecular supercapacitor system, which demonstrated good performance even at a low temperature of -20 °C.

12.
Support Care Cancer ; 30(4): 3043-3055, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34741654

RESUMO

BACKGROUND: Nondrug treatments are potentially beneficial for cancer patients. However, the effect of sleep on cancer-related fatigue (CRF) and quality of life (QOL) in cancer patients remains unclear. We conducted a meta-analysis of randomized controlled trials to examine the efficacy of sleep in cancer patients undergoing treatment. METHODS: The PubMed, Ovid, Embase, Cochrane Central Register of Controlled Trials, and China National Knowledge Infrastructure databases were searched to identify suitable studies. Stata 15.0 software was used for statistical analyses. Sensitivity analyses were conducted. Fourteen studies (6 in English and 8 in Chinese) involving 1151 patients were included in the meta-analysis. Ten, five, and six studies that assessed the effects of sleep on CRF, QOL, and quality of sleep, respectively, in cancer patients undergoing treatment were identified. RESULTS: Sleep interventions significantly affected overall CRF (standardized mean difference (SMD) = -1.52, P < 0.01), overall QOL (SMD = 1.20, P < 0.01), physical fatigue (SMD = -0.66, P < 0.01), cognitive fatigue (SMD = -0.38, P = 0.015), and physical function (SMD = 0.64, P < 0.01). Comprehensive intervention measures focusing on sleep, sleep nondrug interventions, and interventions for ≥3 or <3 months affect CRF. However, no significant effects on emotional fatigue, emotional function, perpetual fatigue, depression, or quality of sleep were observed. CONCLUSIONS: Comprehensive interventions focusing on sleep are helpful for CRF. Sleep interventions may only affect physiological function and have no effect on emotional function, perpetual function, or sleep quality. Future research should focus on how to combine sleep interventions with psychological, social, cognitive, and emotional interventions and provide targeted comprehensive nursing measures to better improve CRF, sleep quality, and QOL.


Assuntos
Neoplasias , Qualidade de Vida , China , Fadiga/etiologia , Fadiga/terapia , Humanos , Neoplasias/complicações , Neoplasias/psicologia , Neoplasias/terapia , Sono
13.
Arch Insect Biochem Physiol ; 111(1): e21902, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35403741

RESUMO

Ledrinae is a unique group of leafhoppers with a distinct appearance. Petalocephala is the largest Ledrinae genus that is difficult to identify except by dissecting the male genitals. To date, research on Ledrinae is relatively less compared with other leafhoppers. Therefore, to better understand this group, we sequenced and analyzed three complete Petalocephala mitochondrial genomes. We comparatively analyzed these general Petalocephala genomic features (including size, AT content, AT/GC skew, 13 protein-coding gene nucleotide compositions, etc.), and predicted 22 transfer RNA secondary structures. We obtained highly consistent phylogenetic results within Cicadellidae based on mitogenomic data using the maximum likelihood and Bayesian methods. Our results showed that all subfamilies were monophyletic and had a high node support rate, and there was a sister group relationship between Ledrinae and all other leafhopper groups. Furthermore, treehoppers were found to originate from leafhoppers and showed sister group relationships with Megophthalminae. Within Ledrinae, all phylogenetic trees supporting phylogenetic relationships were as follows: ([P. dicondylica + P. gongshanensis] + [Tituria pyramidata + [Ledra auditura + P. gongshanensis]]) Based on the complete mitogenome phylogenetic analysis and the comparison of morphological characteristics, we propose that Petalocephala is not monophyletic.


Assuntos
Genoma Mitocondrial , Hemípteros , Animais , Composição de Bases , Teorema de Bayes , Filogenia
14.
Chem Soc Rev ; 50(16): 9022-9054, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34137396

RESUMO

Thermoelectric energy conversion is an all solid-state technology that relies on exceptional semiconductor materials that are generally optimized through sophisticated strategies involving the engineering of defects in their structure. In this review, we summarize the recent advances of defect engineering to improve the thermoelectric (TE) performance and mechanical properties of inorganic materials. First, we introduce the various types of defects categorized by dimensionality, i.e. point defects (vacancies, interstitials, and antisites), dislocations, planar defects (twin boundaries, stacking faults and grain boundaries), and volume defects (precipitation and voids). Next, we discuss the advanced methods for characterizing defects in TE materials. Subsequently, we elaborate on the influences of defect engineering on the electrical and thermal transport properties as well as mechanical performance of TE materials. In the end, we discuss the outlook for the future development of defect engineering to further advance the TE field.

15.
Nano Lett ; 21(12): 5401-5408, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34125537

RESUMO

Room-temperature sodium-sulfur batteries have potential in stationary applications, but challenges such as loss of active sulfur and low electrical conductivity must be solved. Nitrogen-doped nanocarbon host cathodes have been employed in metal-sulfur batteries: polar interactions mitigate the loss of sulfur, while the conductive nanostructure addresses the low conductivity. Nevertheless, these two properties run contrary to each other as greater nitrogen-doping of nanocarbon hosts is associated with lower conductivity. Herein, we investigate the polarity-conductivity dilemma to determine which of these properties have the stronger influence on cycling performance. Lower carbonization temperatures produce more pyridinic nitrogen and pyrrolic nitrogen, which from density functional theory calculations preferentially bind discharge products (Na2S and short-chain polysulfides). Despite its lower conductivity, the highly doped composite showed better Coulombic efficiency and stability, retaining a high capacity of 980 mAh g(S)-1 after 800 cycles. Our findings represent a paradigm shift where nitrogen-doping should be prioritized in designing shuttle-free, long-life sodium-sulfur batteries.

16.
Radiology ; 301(1): 154-162, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34374594

RESUMO

Background The value of measuring mechanical properties to categorize various pathophysiologic states of the liver is as yet undetermined in chronic hepatitis B (CHB) or C (CHC). Purpose To evaluate multiparametric three-dimensional (3D) MR elastography as a means of detecting early necroinflammation, distinguishing necroinflammation from fibrosis, and gauging the severity of portal hypertension (PH) in CHB or CHC. Materials and Methods From January 2015 to September 2019, participants with CHB or CHC were prospectively enrolled from a single institution and were divided into two groups: those with liver biopsy and no evidence of PH (group 1) and those with PH and a hepatic venous pressure gradient (HVPG) measurement (group 2). For group 3, healthy volunteers were separately recruited from a nearby community. Multiple viscoelastic parameters (shear stiffness [SS], storage modulus, loss modulus, and damping ratio [DR]) were determined at 3D MR elastography at 60 Hz, and multivariable logistic or linear regression analysis was used to assess associations of mechanical parameters with histologic scores and HVPG. Results A total of 155 participants (median age, 41 years [interquartile range, 32-48 years]; 85 women) were in group 1 (training set: n = 78, validation set: n = 77), 85 participants (median age, 57 years [interquartile range, 43-61 years]; 51 women) in group 2, and 60 healthy volunteers (median age, 49 years [interquartile range, 27-64 years]; 38 men) in group 3. The liver DR was higher in participants with necroinflammation (DR, 0.13 ± 0.03) versus those without (at liver fibrosis stage F0) (DR, 0.10 ± 0.02; P < .001). Liver DR and SS together performed well in the diagnosis of necroinflammation (area under the receiver operating characteristic curve [AUC], 0.88 [95% CI: 0.79, 0.96]) and the scoring of moderate to severe activity (AUC, 0.88 [95% CI: 0.81, 0.95]) in the validation data set. Liver DR (regression coefficient [ß] = -30.3 [95% CI: -58.0, -2.5]; P = .03) and splenic SS (ß = 2.3 [95% CI: 1.7, 2.9]; P < .001) were independently associated with HVPG. Conclusion Three-dimensional MR elastography may detect early necroinflammation, distinguish necroinflammation from liver fibrosis, and correlate with hepatic venous pressure gradient in chronic hepatitis B and C. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Reeder in this issue.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Hepatite B Crônica/complicações , Hepatite C Crônica/complicações , Hipertensão Portal/complicações , Imageamento Tridimensional/métodos , Inflamação/diagnóstico por imagem , Cirrose Hepática/complicações , Adulto , Estudos Transversais , Feminino , Humanos , Hipertensão Portal/diagnóstico por imagem , Hipertensão Portal/patologia , Inflamação/complicações , Inflamação/patologia , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
17.
Analyst ; 145(5): 1810-1816, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-31951229

RESUMO

An electrochemiluminescence (ECL) sensor based on a benzo[3]uril-modified glassy carbon electrode with sensitized luminescence, with the coexistence of 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) as the coreactant, was successfully constructed. The sensitization mechanism was proposed by analyzing the results of the control experiments for establishing the relationship of the luminescence effect with the concentration of HEPES. Under the optimized conditions, the fabricated sensor system was applied for the detection of Fe3+ in an aqueous solution with good sensitivity and selectivity. A low detection limit of 0.41 nM was achieved, indicating superior sensor performance over the previous analytical methods. The ECL sensor system was employed for the detection of Fe3+ in human serum samples to produce excellent recoveries ranging from 96.17% to 101.81%.


Assuntos
Benzimidazóis/química , Técnicas Eletroquímicas/métodos , HEPES/química , Ferro/sangue , Substâncias Luminescentes/química , Medições Luminescentes/métodos , Técnicas Eletroquímicas/instrumentação , Eletrodos , Humanos , Ferro/química , Limite de Detecção , Oxirredução
18.
J Am Chem Soc ; 141(48): 18984-18993, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31707782

RESUMO

Multivariate metal-organic frameworks (MTV-MOFs) incorporating multiple chemical functionalities within single-phase crystalline materials show superior properties that arise from synergistic effects. Herein, we report an efficient and versatile method for the growth of highly oriented multivariate surface-attached MOFs (MTV-SURMOFs) by the combination of the liquid-epitaxial growth method (LPE) and the mixed-linker strategy. Twenty-six MTV-SURMOFs of the [M2L2P] type with a maximum of five different dicarboxylate linkers (L) were deposited onto suitably functionalized surfaces. Systematic studies by infrared reflection absorption (IRRA) spectroscopy and surface XRD provide evidence for the formation of highly oriented MTV-SURMOFs. Interestingly, the pKa's of the dicarboxylate linkers play a crucial role for the orientational quality of the MTV-SURMOFs. In addition, benzene uptake experiments showed that the MTV-SURMOFs exhibit up to 2.6 times higher adsorption capacity as compared to the single-linker SURMOFs, demonstrating the synergistic effects in these surface systems.

19.
Int J Cancer ; 144(9): 2227-2238, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30374974

RESUMO

Vasculogenic mimicry (VM) is a special vascular pattern in malignant tumors, which is composed of highly aggressive tumor cells. This tumor cell-mediated blood supply pattern is closely associated with a poor prognosis in cancer patients. The interaction of axon guidance factor Sema4D and its high affinity receptor plexinB1 could activate small GTPase RhoA and its downstream ROCKs; this process has an active role in the migration of endothelial cells and tumor angiogenesis. Here, we have begun to uncover the role of this pathway in VM formation in non-small cell lung cancer (NSCLC). First, we confirmed this special form of vasculature in NSCLC tissues and found the existence of VM channels in tumor tissues was correlated with Sema4D expression. Further, we found that inhibition of Sema4D in the human NSCLC cells H1299 and HCC827 reduces VM formation both in vitro and in vivo. Moreover, we demonstrated that downregulating the expression of plexinB1 by siRNA expressing vectors and inhibiting the RhoA/ROCK signaling pathway using fasudil can reduce VM formation of H1299 and HCC827 cells. Finally, we found that suppression of Sema4D leads to less stress fibers and depleted the motility of H1299 and HCC827 cells. Collectively, our study implicates Sema4D plays an important role in the process of VM formation in NSCLC through activating the RhoA/ROCK pathway and regulating tumor cell plasticity and migration. Modulation of the Sema4D/plexinB1 and downstream RhoA/ROCK pathway may prevent the tumor blood supply through the VM pattern, which may eventually halt growth and metastasis of NSCLC.


Assuntos
Antígenos CD/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Neovascularização Patológica/patologia , Proteínas do Tecido Nervoso/metabolismo , Receptores de Superfície Celular/metabolismo , Semaforinas/metabolismo , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Células A549 , Animais , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Células Endoteliais/fisiologia , Ativação Enzimática , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas do Tecido Nervoso/genética , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , RNA Interferente Pequeno/genética , Receptores de Superfície Celular/genética , Semaforinas/antagonistas & inibidores , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
20.
Brain Behav Immun ; 81: 111-121, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31176001

RESUMO

PURPOSE: Elevated catecholamines in the tumor microenvironment often correlate with tumor development. However, the mechanisms by which catecholamines modulate lung cancer growth are still poorly understood. This study is aimed at examining the functions and mechanisms of catecholamine-induced macrophage polarization in angiogenesis and tumor development. EXPERIMENTAL DESIGN: We established in vitro and in vivo models to investigate the relationship between catecholamines and macrophages in lung cancer. Flow cytometry, cytokine detection, tube formation assay, immunofluorescence, and western blot analysis were performed, and animal models were also used to explore the underlying mechanism of catecholamine-induced macrophage polarization and host immunological response. RESULTS: Catecholamines were shown to be secreted into tumor under the control of the sympathetic nerve system to maintain the pro-tumoral microenvironment. In vivo, the chemical depletion of the natural catecholamine stock with 6OHDA could reduce the release of catecholamines within tumor tissues, restrain the function of alternatively activated M2 macrophage, attenuate tumor neovascularization, and inhibit tumor growth. In vitro, catecholamine treatment triggered the M2 polarization of macrophages, enhanced the expression of VEGF, promoted tumor angiogenesis, and these catecholamine-stimulated effects could be reversed by the adrenergic receptor antagonist propranolol. In addition to regulating tumor-associated macrophages (TAM) recruitment, decreasing catecholamine levels could also shift the immunosuppressive microenvironment by decreasing myeloid-derived suppressor cells' (MDSCs) recruitment and facilitating dendritic cells' (DCs) activation, potentially resulting in a positive antitumor immune response. CONCLUSION: Our study demonstrates the potential of adrenergic stress and catecholamine-driven adrenergic signaling of TAMs to regulate the immune status of a tumor microenvironment and provides promising targets for anticancer therapies.


Assuntos
Catecolaminas/metabolismo , Neoplasias Pulmonares/metabolismo , Neovascularização Patológica/fisiopatologia , Animais , Catecolaminas/fisiologia , Linhagem Celular Tumoral , Movimento Celular/imunologia , Citocinas/metabolismo , Humanos , Ativação de Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Transdução de Sinais , Microambiente Tumoral
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