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1.
Small ; 20(25): e2309926, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38196153

RESUMO

As one type of recent emerging lead-free perovskites, Cs2ZrCl6 nanocrystals are widely concerned, benefiting from the eminent designability, high X-ray cutoff efficiency, and favorable stability. Improving the luminescence performance of Cs2ZrCl6 nanocrystals has great importance to cater for practical applications. In view of the surface defects frequently formed by the liquid phase method, the particle morphology and surface quality of this material are expected to be regulated if certain intervention is made in the synthesis process. In the work, differing from normal cell lattice modulation based on the ion doping, the grain size and surface morphology of Cs2ZrCl6 nanocrystals are optimized via adding a certain amount of InCl3 to the synthetic solution. The surface defects are restored to inhibit the defect-induced non-radiative transition, resulting in the improvement of the luminescence properties. Moreover, a flexible Cs2ZrCl6@polydimethylsiloxane film with excellent heat, water, and bending resistance and a light-emitting diode (LED) device are fabricated, exhibiting excellent application potential for X-ray imaging and blue LED.

2.
Clin Exp Rheumatol ; 42(2): 269-276, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38147318

RESUMO

OBJECTIVES: This study aimed to describe the clinical features of patients with anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibody-positive dermatomyositis (DM) who had macrophage activation syndrome (MAS). METHODS: We retrospectively examined 44 patients with anti-MDA5-positive DM and compared the clinical features between patients with MAS (n = 11) and those without (n=33). Patients without MAS were selected randomly in the same year as those with MAS at a ratio of 3:1. Among patients with MAS, we compared the features between non-survivors and survivors. We used Fisher's exact test, Student's t test, the Mann-Whitney U test and the log-rank test for statistical analysis. RESULTS: Patients complicated with MAS had a significantly higher incidence of infection, heliotrope sign, Gottron's papule, V-neck sign, and higher serum levels of ferritin, aspartate aminotransferase (AST), lactic dehydrogenase (LDH), and creatine kinase (CK) than those without MAS (p<0.05). Among the 11 patients with MAS, 4 (36.4%) died after intensive treatment. Deceased patients were older, given more combination therapy with tofacitinib (TOF) and had a higher incidence of rapid progressive interstitial lung disease, infection, heart failure and renal impairment than those who survived (p<0.05). CONCLUSIONS: Among anti-MDA5-positive DM, Infection, DM typical rashes, and higher serum levels of ferritin, AST, LDH, and CK were more common in patients complicated with MAS. The mortality of patients with MAS was high, particularly among patients who were older, given more combination therapy with TOF, and had RP-ILD, infection, heart failure and renal impairment.


Assuntos
Dermatomiosite , Insuficiência Cardíaca , Doenças Pulmonares Intersticiais , Síndrome de Ativação Macrofágica , Humanos , Prognóstico , Dermatomiosite/diagnóstico , Dermatomiosite/tratamento farmacológico , Estudos Retrospectivos , Síndrome de Ativação Macrofágica/diagnóstico , Síndrome de Ativação Macrofágica/complicações , Helicase IFIH1 Induzida por Interferon , Autoanticorpos , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/complicações , Ferritinas , Insuficiência Cardíaca/complicações
3.
Angew Chem Int Ed Engl ; 62(39): e202309929, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37584440

RESUMO

The regeneration of the reduced form cofactor NAD(P)H is essential for the extra-cellular application of bio-reduction, which necessitates not only the development of efficient artificial NAD(P)H regeneration catalytic system but also its well compatibility with the cascade enzymatic reduction system. In this work, we reported the preparation of a metal nanoparticle (NP) and metal complex integrated core-shell nanoreactor for H2 -driven NAD(P)H regeneration through the immobilization of a Rh complex on Ni/TiO2 surface via a bipyridine contained 3D porous organic polymer (POP). In comparison with the corresponding single component metal NPs and the immobilized Rh complex, the integrated catalyst presented simultaneously enhanced activity and selectivity in NAD(P)H regeneration thanks to the rapid spillover of activated H species from metal NPs to Rh complex. In addition, the size-sieving effect of POP precluded the direct interaction of enzyme and Rh complex confined in the pores, enabling the success coupling of core-shell nanoreactor and aldehyde ketone reductase (AKR) for chemoenzymatic reduction of acetophenone to (R)-1-phenylethan-1-ol. This work provides a strategy for the rational manipulation of multicomponent cooperation catalysis.


Assuntos
Complexos de Coordenação , NAD , Catálise , Regeneração , Nanotecnologia
4.
Angew Chem Int Ed Engl ; 62(43): e202307096, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37394778

RESUMO

Mimicking the structures and functions of cells to create artificial organelles has spurred the development of efficient strategies for production of hollow nanoreactors with biomimetic catalytic functions. However, such structure are challenging to fabricate and are thus rarely reported. We report the design of hollow nanoreactors with hollow multishelled structure (HoMS) and spatially loaded metal nanoparticles. Starting from a molecular-level design strategy, well-defined hollow multishelled structure phenolic resins (HoMS-PR) and carbon (HoMS-C) submicron particles were accurately constructed. HoMS-C serves as an excellent, versatile platform, owing to its tunable properties with tailored functional sites for achieving precise spatial location of metal nanoparticles, internally encapsulated (Pd@HoMS-C) or externally supported (Pd/HoMS-C). Impressively, the combination of the delicate nanoarchitecture and spatially loaded metal nanoparticles endow the pair of nanoreactors with size-shape-selective molecular recognition properties in catalytic semihydrogenation, including high activity and selectivity of Pd@HoMS-C for small aliphatic substrates and Pd/HoMS-C for large aromatic substrates. Theoretical calculations provide insight into the pair of nanoreactors with distinct behaviors due to the differences in energy barrier of substrate adsorption. This work provides guidance on the rational design and accurate construction of hollow nanoreactors with precisely located active sites and a finely modulated microenvironment by mimicking the functions of cells.

5.
Rheumatology (Oxford) ; 61(9): 3704-3710, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34940809

RESUMO

OBJECTIVE: Rapidly progressive interstitial lung disease (RP-ILD) in DM patients positive for anti-melanoma differentiation-associated gene 5 (anti-MDA5) autoantibody (MDA5-DM) often have a poor prognosis, frequently fatal. As there is a scarcity of data regarding the effect of intravenous immunoglobulin (IVIG) on RP-ILD in MDA5-DM patients (MDA5-RPILD), we conducted this study to determine the efficacy of a IVIG add-on initial treatment. METHODS: Patients with newly-onset MDA5-RPILD from September 2018 to June 2020 were retrospectively reviewed for 6 months in the First Affiliated Hospital of Zhengzhou University. They were divided into two groups: IVIG and non-IVIG groups. The major measurement of treatment outcome was the difference in the mortality in 3-month and 6-month between two group patients. Other relevant indicators were also recorded, including the incidence of infection, the dosages of GCs, the remission rate and the variables in laboratory data. RESULTS: The IVIG group (n = 31) showed significantly lower 6-month mortality rate than the non-IVIG group (n = 17) (22.6% vs 52.9%; P =0.033). The IVIG group patients had a higher remission rate at 3 months (71.0% vs 41.2%; P =0.044). Gradual reduction was observed in the first 3 months with regard to the titre of anti-MDA5 autoantibody, the serum level of ferritin and the ground glass opacification GGO scores. CONCLUSION: IVIG adjunct therapy is a very effective first-line treatment for patients with MDA5-RPILD. IVIG may increase the survival and remission rate by lowering ferritin concentration, anti-MDA5 titre and GGO score.


Assuntos
Dermatomiosite , Doenças Pulmonares Intersticiais , Autoanticorpos , Dermatomiosite/complicações , Ferritinas , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Prognóstico , Estudos Retrospectivos
6.
Clin Exp Rheumatol ; 40(2): 304-308, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35084311

RESUMO

OBJECTIVES: We aimed to identify different subtypes of dermatomyositis (DM) patients positive with anti-melanoma differentiation-associated gene 5 antibody (DM-MDA5+) for customised treatments to improve the outcomes. METHODS: Among 96 DM-MDA5+ patients, subgroups with similar phenotypes were delineated using hierarchical clustering analysis of the clinico-biological characteristics. Classification and regression trees were used to build a classification model and survival analysis was used to evaluate the prognoses of subgroups. RESULTS: Three subgroups were identified among 96 DM-MDA5+ patients, and patients in different subgroups had highly heterogenic manifestations and outcomes. Cluster 1 patients were referred to as mild group of rheumatologic patterns with good prognosis. Cluster 2 patients were referred to as young typical DM group with good prognosis. Cluster 3 patients were referred to as elderly rapidly progressive interstitial lung disease (RPILD) group with poor prognosis. A predictive model to classify patients was established, and three critical factors were found, including age, serum ferritin and myalgia. CONCLUSIONS: DM-MDA5+ patients have a poor short-term prognosis. Three clinical phenotypes with different prognoses were identified in DM-MDA5+ patients.


Assuntos
Dermatomiosite , Doenças Pulmonares Intersticiais , Idoso , Autoanticorpos , Dermatomiosite/complicações , Humanos , Helicase IFIH1 Induzida por Interferon/genética , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/genética , Fenótipo , Prognóstico , Estudos Retrospectivos
7.
Small ; 17(9): e1906250, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32406190

RESUMO

Heterogeneous hydrogenation reactions are of great importance for chemical upgrading and synthesis, but still face the challenges of controlling selectivity and long-term stability. To improve the catalytic performance, many hydrogenation reactions utilize special yolk/core-shell nanoreactors (YCSNs) with unique architectures and advantageous properties. This work presents the developmental and technological challenges in the preparation of YCSNs that are potentially useful for hydrogenation reactions, and provides a summary of the properties of these materials. The work also addresses the scientific challenges in applications of these YCSNs in various gas and liquid-phase hydrogenation reactions. The catalyst structures, catalytic performance, structure-performance relationships, reaction mechanisms, and unsolved problems are discussed too. Also, a brief outlook and opportunities for future research in this field are presented. This work on the advancements in YCSNs might inspire the creation of new materials with desired structures for achieving maximal hydrogenation performances.


Assuntos
Nanotecnologia , Catálise , Hidrogenação
8.
Opt Lett ; 45(21): 5986-5989, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33137050

RESUMO

It is a daunting challenge to realize ultraviolet C (UVC) lasing (i.e., has a wavelength range from 200 to 275 nm) from upconversion nanocrystals due to their low upconversion efficiency. Here, we fabricate Ba2LaF7:Yb3+(90mol%), Tm3+(5mol%) upconversion nanocrystals from amorphous borosilicate glass to support emission at ∼263nm under 980 nm ns laser excitation. The excitation threshold can be further reduced from ∼130 to ∼26.5mJ/cm2 by using a cylindrical microcavity. We also found that the growth of defect-free Ba2LaF7 nanocrystals with a high concentration of codoping Yb3+ and Tm3+ ions inside high optical damage threshold borosilicate glass is the key to achieving room-temperature UVC upconversion lasing under high-intensity excitation.

9.
Angew Chem Int Ed Engl ; 58(41): 14483-14488, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31350802

RESUMO

It is a challenging task to promote the activity and selectivity of a catalyst via precisely engineering the microenvironment, an important factor related with the catalytic performance of natural catalysts. Motivated by the water effect in promoting the catalytic activity explored in this work, a nanoreactor modified with phosphine ligand enabled the efficient hydrogenation of benzoic acid (BA) over Ru nanoparticles (NPs) in organic solvent under mild conditions, which cannot be achieved in unmodified nanoreactors. Both density functional theory (DFT) calculations and catalytic performance tests showed that the phosphine ligands can manipulate the adsorption strength of BA on Ru NPs by tuning the surface properties as well as preferentially interacting with the carboxyl of BA. The insights obtained in the present study provide a novel concept of nanoreactor design by anchoring ligands near catalytically active centers.

11.
Chemistry ; 23(48): 11504-11508, 2017 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-28691758

RESUMO

Developing solid catalysts with multiple active sites working cooperatively is desirable for efficient chemical transformations. However, most solid catalysts are rigid and impede the cooperation between their spatially isolated active sites. Two flexible porous organic frameworks (POFs) with integrated Co(salen) as active sites have been successfully synthesized for mimicking the cooperative modes of enzymes. The POFs exhibit second-order rate dependence on Co(salen) concentration in the network and afford much higher TOF (3300 versus 2670 h-1 ) than the homogeneous counterpart in the hydration of propylene epoxide. POFs with a flexible network thus not only facilitate but also enhance the cooperation of nearby Co(salen). Moreover, POFs could catalyze oversized substrates, have a wide substrate scope, and exhibit high stability.

12.
Chemistry ; 23(32): 7791-7797, 2017 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28397311

RESUMO

Chemoselective hydrogenation of substrates with more than one functional group that could be hydrogenated is quite challenging and is of fundamental importance. Here, the enhanced chemoselectivity of ultrasmall (<1 nm) platinum nanoparticles (NPs) stabilized on silica modified with triphenylphosphine (PSiO2 ) in hydrogenation reactions is reported. Platinum NPs on PSiO2 exhibit much higher selectivity than those on SiO2 in the hydrogenation of acetophenone to 1-phenylethanol (99.9 versus 36 %) and hydrogenation of phenylacetylene to styrene (85 versus 52 %). The results of NMR spectroscopy, X-ray photoelectron spectroscopy, and in situ CO adsorption FTIR spectroscopy indicate the existence of strong interactions between triphenylphosphine and Pt NPs. Consequently, Pt NPs on PSiO2 have smaller particle sizes and more positive Pt 4 f binding energy than those of Pt/SiO2 ; these are the main contributors to the superior chemoselectivity of Pt NPs. The organically modified silica could act as an efficient solid ligand for tuning the catalytic performance of metal NPs.

13.
J Magn Reson Imaging ; 45(3): 741-750, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27527587

RESUMO

PURPOSE: To evaluate the value of T2 , T1 rho, and diffusion metrics in assessment of liver fibrosis in rats. MATERIALS AND METHODS: Liver fibrosis in a rat model (n = 72) was induced by injection of carbon tetrachloride (CCl4 ) at 3T. T2 , T1 rho, and diffusion parameters (apparent diffusion coefficient (ADC), Dtrue ) via spin echo (SE) diffusion-weighted imaging (DWI) and stimulated echo acquisition mode (STEAM) DWI with three diffusion times (DT: 80, 106, 186 msec) were obtained in surviving rats with hepatic fibrosis (n = 52) and controls (n = 8). Liver fibrosis stage (F0-F6) was identified based on pathological results using the traditional liver fibrosis staging method for rodents. Nonparametric statistical methods and receiver operating characteristic (ROC) curve analysis were employed to determine the diagnostic accuracy. RESULTS: Mean T2 , T1 rho, ADC, and Dtrue with DT = 186 msec correlated with the severity of fibrosis with r = 0.73, 0.83, -0.83, and -0.85 (all P < 0.001), respectively. The average areas under the ROC curve at different stages for T1 rho and diffusion parameters (DT = 186 msec) were larger than those of T2 and SE DWI (0.92, 0.92, and 0.92 vs. 0.86, 0.82, and 0.83). The corresponding average sensitivity and specificity for T1 rho and diffusion parameters with a long DT were larger (89.35 and 88.90, 88.36 and 89.97, 90.16 and 87.13) than T2 and SE DWI (90.28 and 79.93, 85.30 and 77.64, 78.21 and 82.41). The performances of T1 rho and Dtrue (DT = 186 msec) were comparable (average AUC: 0.92 and 0.92). CONCLUSION: Among the evaluated sequences, T1 rho and STEAM DWI with a long DT may serve as superior imaging biomarkers for assessing liver fibrosis and monitoring disease severity. LEVEL OF EVIDENCE: 1 J. Magn. Reson. Imaging 2017;45:741-750.


Assuntos
Algoritmos , Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/fisiopatologia , Animais , Difusão , Aumento da Imagem/métodos , Cirrose Hepática/patologia , Campos Magnéticos , Masculino , Doses de Radiação , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
J Magn Reson Imaging ; 44(6): 1556-1564, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27227674

RESUMO

PURPOSE: To determine the capacity of intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) in differential diagnosis between recurrent carcinoma and postchemoradiation fibrosis of skull base in patients with nasopharyngeal carcinoma (NPC). MATERIALS AND METHODS: Eleven patients with recurrent NPC and 21 patients with postchemoradiation fibrosis in the skull base were enrolled. All the diagnoses were proved by endoscopic biopsy or imaging follow-up. IVIM MRI was performed to obtain quantitative parameters including D (pure diffusion), f (perfusion fraction), and D* (pseudodiffusion). D, f, and D* were compared between two groups; the diagnostic performances of D and f were evaluated using the receiver operating characteristic (ROC) analysis. RESULTS: D and f values were significantly lower in recurrent carcinoma than that in fibrosis (P < 0.001; P = 0.001). No significant difference was found in D* values between recurrent carcinoma and fibrosis (P = 0.229). ROC curve analysis showed that the area under the curve of D and f values were 0.996 and 0.838, respectively. Respective cutoff values with sensitivity, specificity, and accuracy were: D = 1.161 × 10-3 mm2 /s (sensitivity 100.0%, specificity 95.2%, accuracy 96.9%), f = 0.109 (sensitivity 81.8%, specificity 71.4%, accuracy 75.0%). CONCLUSION: Recurrent NPC and postchemoradiation fibrosis in the skull base have distinctive D and f values. IVIM MRI could be used to differentiate between recurrent carcinoma and postchemoradiation fibrosis in patients with NPC. J. Magn. Reson. Imaging 2016;44:1556-1564.


Assuntos
Carcinoma/diagnóstico por imagem , Carcinoma/terapia , Quimiorradioterapia/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/terapia , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/prevenção & controle , Base do Crânio/patologia , Adulto , Idoso , Carcinoma/patologia , Quimiorradioterapia/efeitos adversos , Feminino , Fibrose , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patologia , Recidiva Local de Neoplasia/patologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Base do Crânio/diagnóstico por imagem , Base do Crânio/efeitos da radiação , Resultado do Tratamento
15.
J Magn Reson Imaging ; 44(4): 880-9, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27038128

RESUMO

PURPOSE: The relationship between severe liver iron overload (LIO) and heart iron overload (HIO) in transfusion-dependent patients with thalassemia major (TM) is uncertain. Whether severe LIO can serve as an index for assessing heart iron deposition has vital clinical significance. Therefore, our aim is to determine if a close relationship exists between severe LIO and HIO. MATERIALS AND METHODS: We examined 110 TM patients who underwent T2* measurement in the liver and heart on a 1.5 Tesla MRI scanner. Various statistical analysis methods were used to assess the relationship. RESULTS: Most of these patients suffered from severe LIO (58.18%, liver T2* < 1.4 ms). Both Pearson's and Spearman's tests showed a significant correlation between liver T2* and heart T2* values (with a correlation coefficient of 0.408 and 0.550, respectively, both P < 0.0001). A nonlinear model, with the equation of Heart T2* = 37.974-17.684 / Liver T2*, was found to be the best model to indicate the relationship between liver T2* and heart T2*. Receiver operating characteristic (ROC) analysis showed the area under the ROC curve of liver T2* and serum ferritin for predicting HIO was 0.812 (95% confidence interval [CI]: 0.731-0.892; P < 0.0001) and 0.69 (95% CI: 0.585-0.795; P = 0.001), respectively. CONCLUSION: Our preliminary data suggest the existence of a close relationship between severe LIO and HIO. High liver iron levels appear to increase the risk of heart iron deposition. This further supports the concept of critical liver iron concentration, above which elevated heart iron is present. J. MAGN. RESON. IMAGING 2016;44:880-889.


Assuntos
Sobrecarga de Ferro/metabolismo , Ferro/metabolismo , Hepatopatias/metabolismo , Fígado/metabolismo , Miocárdio/metabolismo , Talassemia beta/metabolismo , Adolescente , Adulto , Biomarcadores/metabolismo , Criança , Pré-Escolar , Feminino , Humanos , Sobrecarga de Ferro/diagnóstico por imagem , Fígado/diagnóstico por imagem , Hepatopatias/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição Tecidual , Adulto Jovem , Talassemia beta/diagnóstico por imagem
16.
J Magn Reson Imaging ; 44(4): 906-13, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27149283

RESUMO

PURPOSE: To compare visual quality and quantitative measurements of multislice (MS) breath-hold and 3D respiratory-triggered T1 ρ sequences. MATERIALS AND METHODS: T1 ρ scans including MS BLOCK T1 ρ, MS HS8 T1 ρ, and 3D BLOCK T1 ρ were performed on 40 healthy volunteers and 17 liver cirrhosis patients on 3.0T magnetic resonance imaging (MRI). The MS breath-hold methods scanned three slices while the 3D method covered 26 slices. Visual scores of image quality, T1 ρ measurements of the three sequences, and T1 ρ values of healthy volunteers and cirrhosis patients were compared using parametric tests. RESULTS: Average visual scores for volunteers and patients of the three sequences were 3.19 and 2.82 for MS BLOCK T1 ρ; 3.71 and 3.59 for MS HS8 T1 ρ; 3.29 and 3.59 for 3D BLOCK T1 ρ, respectively. Difference of visual scores among the three groups was significant (P < 0.001). Differences in T1 ρ values among the three methods were significant (P < 0.001). Difference of T1 ρ between MS BLOCK T1 ρ and 3D BLOCK T1 ρ was not significant (volunteer: P = 0.82, patient: 0.92) while the difference of T1 ρ between MS BLOCK T1 ρ and MS HS8 T1 ρ, MS HS8 T1 ρ and 3D BLOCK T1 ρ was significant in both volunteers and patients (P < 0.01). Differences of T1 ρ between healthy volunteers and patients were all significant in three T1 ρ sequences (P = 0.04, 0.004, 0.03). CONCLUSION: Of the tested sequences, the image quality of MS HS8 T1 ρ was best, but 3D BLOCK T1 ρ with respiratory triggering should also be considered as an alternative sequence for clinical diagnosis of liver cirrhosis due to its superior coverage. J. MAGN. RESON. IMAGING 2016;44:906-913.


Assuntos
Artefatos , Suspensão da Respiração , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Cirrose Hepática/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Técnicas de Imagem de Sincronização Respiratória/métodos , Adulto , Feminino , Humanos , Aumento da Imagem/métodos , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Valores de Referência , Reprodutibilidade dos Testes , Mecânica Respiratória , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Adulto Jovem
17.
Appl Opt ; 55(2): 242-7, 2016 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-26835758

RESUMO

Accurate underwater gas pipeline leak localization requires particular attention due to the sensitivity of environmental conditions. Experiments were performed to analyze the localization performance of a distributed optical fiber sensing system based on the hybrid Sagnac and Mach-Zehnder interferometer. The traditional null frequency location method does not easily allow accurate location of the leakage points. To improve the positioning accuracy, the particle swarm optimization algorithm (PSO) tuning of the support vector machine (SVM) was used to predict the leakage points based on gathered leakage data. The PSO is able to optimize the SVM parameters. For the 10 km range chosen, the results show the PSO-SVM average absolute error of the leakage points predicted is 66 m. The prediction accuracy of leakage points is 98.25% by PSO tuning of the SVM processing. For 20 leakage test data points, the average absolute error of leakage point location is 124.8 m. The leakage position predicted by the PSO algorithm after optimization of the parameters is more accurate.

18.
Chemistry ; 21(29): 10490-6, 2015 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-26094810

RESUMO

The synthesis of silica-based yolk-shell nanospheres confined with ultrasmall platinum nanoparticles (Pt NPs) stabilized with poly(amidoamine), in which the interaction strength between Pt NPs and the support could be facilely tuned, is reported. By ingenious utilization of silica cores with different surface wettability (hydrophilic vs. -phobic) as the adsorbent, Pt NPs could be confined in different locations of the yolk-shell nanoreactor (core vs. hollow shell), and thus, exhibit different interaction strengths with the nanoreactor (strong vs. weak). It is interesting to find that the adsorbed Pt NPs are released from the core to the hollow interiors of the yolk-shell nanospheres when a superhydrophobic inner core material (SiO2 -Ph) is employed, which results in the preparation of an immobilized catalyst (Pt@SiO2-Ph); this possesses the weakest interaction strength with the support and shows the highest catalytic activity (88 500 and 7080 h(-1) for the hydrogenation of cyclohexene and nitrobenzene, respectively), due to its unaffected freedom of Pt NPs for retention of the intrinsic properties.

19.
J Magn Reson Imaging ; 42(3): 737-45, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26154874

RESUMO

BACKGROUND: To determine optimal initial age of cardiac iron screening with magnetic resonance imaging (MRI) T2* in patients with thalassemia major (TM). METHODS: We retrospectively reviewed black blood cardiac T2* assessments from 102 TM patients from the ages of 3 to 32 years. Cases of patients under and above 7 years old with detectable cardiac iron overload were analyzed separately. Associations between cardiac T2* and various factors, such as serum ferritin (SF), patient age and hepatic T2*, were assessed using either scatterplots or regression. Images were evaluated by two independent radiologists. RESULTS: With a T2* cut-off value of 20 ms, no patient under 5 years old showed cardiac iron overload. Three of 19 (15.8%) patients under 7 years of age had a cardiac T2* ≤ 20 ms (5.5 to 7 years) but none had ≤10 ms, while 35 of 83 (42.2%) patients above 7 years old had a cardiac T2* ≤ 20 ms (8 to 32 years) and 18 of them ≤10 ms. Cardiac T2* correlated weakly with serum ferritin and liver T2* (r = -0.39 and 0.41, respectively, both P < 0.001), but not with patient age (P > 0.05). CONCLUSION: Cardiac iron overload can occur in young TM patients, even as young as 5.5 years old. Assessment of cardiac iron with T2* might need to begin as early as 5 years old if suboptimal chelation therapy is administered.


Assuntos
Ferro/química , Imageamento por Ressonância Magnética , Talassemia beta/sangue , Talassemia beta/patologia , Adolescente , Adulto , Fatores Etários , Terapia por Quelação , Criança , Pré-Escolar , Feminino , Ferritinas/sangue , Humanos , Ferro/sangue , Sobrecarga de Ferro , Fígado/metabolismo , Masculino , Miocárdio/metabolismo , Radiologia , Análise de Regressão , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
20.
Clin Rheumatol ; 43(6): 1845-1853, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38696116

RESUMO

OBJECTIVE: To investigate the metabolic changes during therapy of tocilizumab (TCZ) and methotrexate (MTX) in non-diabetic rheumatoid arthritis (RA) patients and for the first time explore the associations between metabolic parameters and serum YKL-40 (sYKL-40) levels. METHODS: We enrolled active non-diabetic RA patients who were refractory to MTX. Patients received intravenous TCZ (8 mg/kg) once every 4 weeks combined with MTX for 24 weeks. Metabolic parameters and sYKL-40 levels were measured before TCZ infusion at baseline, week 4, week 12, and week 24. Correlations were assessed by the Spearman's rank correlation analysis. RESULTS: A total of 91 non-diabetic RA patients were enrolled in this study. At week 24, we observed a significant elevation in body mass index (BMI), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG) levels. In contrast, there was a significant decrease in TC/HDL­C ratio. No apparent changes in insulin resistance were found. Additionally, we detected a significant reduction in sYKL-40 levels during the study. At week 24, changes in sYKL-40 levels showed a significant negative correlation (r = -0.334, p = 0.002) with changes in TC levels. CONCLUSION: The combined therapy of TCZ and MTX resulted in a significant increase in BMI and lipid levels, while an evident decrease in the TC/HDL­C ratio and sYKL-40 levels in RA patients. Additionally, there was a significant correlation between the decrease in sYKL-40 levels and the increase in TC levels during treatment with TCZ and MTX. Key Points • Lipid levels elevated significantly and sYKL-40 levels decreased obviously after therapy of TCZ combined with MTX in Chinese RA patients. • There was a significant correlation between the increase in TC levels and the decrease in sYKL-40 levels during treatment with TCZ and MTX in RA patients.


Assuntos
Anticorpos Monoclonais Humanizados , Antirreumáticos , Artrite Reumatoide , Proteína 1 Semelhante à Quitinase-3 , Metotrexato , Humanos , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Proteína 1 Semelhante à Quitinase-3/sangue , Anticorpos Monoclonais Humanizados/uso terapêutico , Metotrexato/uso terapêutico , Antirreumáticos/uso terapêutico , Adulto , Quimioterapia Combinada , Triglicerídeos/sangue , Índice de Massa Corporal , HDL-Colesterol/sangue , Idoso , Colesterol/sangue , China , População do Leste Asiático
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