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1.
Inorg Chem ; 63(15): 6660-6673, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38572776

RESUMO

Although being applied in various fields, white light emitting diodes (WLEDs) still have drawbacks that urgently need to be conquered: the luminescent intensity of commercial phosphors sharply decreases at working temperature. In this study, we calculated the forming energy of defects and confirmed that the VNa defect state can stably exist in ß-NaGdF4, by density functional theory (DFT) calculation. Furthermore, we predicted that the VNa vacancies would provide a zero thermal quenching (ZTQ) property for the ß-NaGdF4-based red-light phosphor. Then, a series of ß-NaGdF4:xEu3+ and ß-NaGdF4:0.25Eu3+,yYb3+ red-light phosphors were synthesized by the hydrothermal method. We found that ß-NaGdF4:0.25Eu3+ and ß-NaGdF4:0.25Eu3+,0.005Yb3+ phosphors possess ZTQ properties at a temperature range between 303-483 K and 303-523 K, respectively. The thermoluminescence (TL) spectra were employed to calculate the depth and density of the VNa vacancies in ß-NaGdF4:0.25Eu3+ and ß-NaGdF4:0.25Eu3+,0.005Yb3+. Combining the DFT calculation with characterization results of TL spectra, it is concluded that electrons stored in VNa vacancies are excited to the exited state of Eu3+ to compensate for the loss of Eu3+ luminescent intensity. This will lead to an increase of luminescent intensity at high temperatures and facilitate the samples to improve ZTQ properties. WLEDs were obtained with CRI = 83.0, 81.6 and CCT = 5393, 5149 K, respectively, when phosphors of ß-NaGdF4:0.25Eu3+ and ß-NaGdF4:0.25Eu3+,0.005Yb3+ were utilized as the red-light source. These results indicate that these two phosphors may become reliable red-light sources with high antithermal quenching properties for WLEDs.

2.
Inorg Chem ; 62(10): 4157-4169, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36856292

RESUMO

Although Mn4+-activated fluoride phosphors have high luminescence quality, their poor water resistance and thermal fluorescence properties significantly limit their practical applications. Here, we propose a surfactant modification strategy by adding the surfactant cetyltrimethylammonium bromide (CTAB) to the synthesis and modifying the surface of the phosphor with ethylene diamine tetraacetic acid (EDTA) to obtain a phosphor with excellent luminescence thermal properties and water resistance, K2TiF6:Mn4+-xCTAB-EDTA (KTFM-xC-E) phosphors. The experimental and X-ray diffraction Rietveld refinement results confirm that the phosphor has higher structural rigidity and thus improved thermal stability. The surface modification with EDTA resulted in the formation of a dilute Mn4+ shell layer on the phosphor surface, which prevented the inward hydrolysis of the phosphor and resulted in excellent water resistance. Therefore, we have successfully modified K2TiF6:Mn4+ (KTFM) phosphors using low-cost surfactants, which also provides new ideas for other commercial high-quality phosphors.

3.
Inorg Chem ; 61(14): 5484-5494, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35349282

RESUMO

Mn4+-doped fluoride phosphors are efficient narrowband red-emitting phosphors for white light-emitting diodes (WLEDs) and backlight displays. However, erosion by moisture is the main obstacle that limits their application. In this work, LNSF:Mn4+ (Li0.06Na1.94Si0.94Mn0.06F6) with high quantum yield (QY), luminescent thermal stability, and waterproofness was synthesized using the H2O2-free reaction method at room temperature. Compared to NSF:Mn4+(Na2Mn0.06Si0.94F6), the QY value, luminescence thermal stability, and water resistance of LNSF:Mn4+ are obviously improved by codoping of Li+ because of the formation of charge-carrier transfer (CT) and rare-Mn4+ layer induced by codoping of Li+. The former produces the negative thermal quenching (NTQ) effect, which results in the improvement of the luminescent thermal stability. The latter can inhibit the hydrolysis of Mn4+ on the surface of the sample, which leads to the enhancement of waterproofness. The formation mechanism of the rare-Mn4+ layer is discussed. A prototype WLED emitting the ideal warm white light (CCT = 3173 K, Ra = 90.4) was assembled by coating a mixture of LNSF:Mn4+, yellow emitting phosphor (YAG:Ce3+), and epoxy resin on the blue light InGaN chip, indicating that the performance of the WLED can be improved by using LNSF:Mn4+.

4.
Nanotechnology ; 31(3): 035404, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31557739

RESUMO

Lithium-sulfur (Li-S) batteries as a new generation of high energy batteries, with low cost and environmentally friendly, have a broad application prospects. While the poor conductivity of sulfur, the volume effect and 'shuttle effect' during charge and discharge, and slow redox kinetics of polysulfide intermediates still limit the practical application. To solve these problems, we synthesize a valid 3D hybrid material (Co9S8@N-CHS) of nanosized Co9S8 evenly distributed on N-doped carbon hollow spheres with strong chemical coupling by in situ carbonization of Co(NO3)2@resorcinol/formaldehyde and sulfidation. It presents a high electronic conductivity, absorbing chemical adsorption capability to polysulfides and can catalyze the sulfur redox processes. Compared with S/AC and S/N-CHS electrodes, S/Co9S8@N-CHS electrodes achieve an excellent initial discharge specific capacity of 1337 mAh g-1 at 0.1 C and a long cycle life with an ultralow capacity decay of 0.027% per cycle over 1000 cycles at 1.0 C and the coulombic efficiency is above 99%. Consequently, it is an effective sulfur host material for high performance Li-S batteries.

5.
BMC Pulm Med ; 20(1): 272, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33076877

RESUMO

BACKGROUND: Previous studies have shown that serum uric acid (UA) levels are correlated with the severity of idiopathic pulmonary arterial hypertension (IPAH) and are predictors of disease prognosis. Still, few studies have explored the value of serum UA in pulmonary arterial hypertension secondary to connective tissue disease (CTD-PAH). This retrospective study aimed to investigate the clinical value of serum UA levels in patients with CTD-PAH. METHODS: Fifty CTD-PAH patients were enrolled in our study, from which baseline UA levels, respective variations, and additional clinical data were collected. The potential association between baseline UA level and severity of CTD-PAH was investigated. Furthermore, the relationship between baseline UA and survival rate of CTD-PAH patients, as well as between UA variations and survival rate of pulmonary hypertension secondary to connective tissue disease (CTD-PH) patients was discussed. RESULTS: Baseline serum UA levels were positively correlated with pulmonary vascular resistance (PVR). During the follow-up period, 3 CTD-PAH and 12 CTD-PH patients died. Kaplan-Meier survival curves showed lower survival rate in patients with hyperuricemia than in patients with normouricemia, in both groups (CTD-PAH group p = 0.041, CTD-PH group p = 0.013). Concerning serum UA variations, patients with persistent hyperuricemia showed the lowest survival rate when compared with patients with steady normouricemia (p = 0.01) or patients with decresing serum UA levels, i.e. undergoing from a status of hyperuricemia to a status of normouricemia (p = 0.023). CONCLUSION: Baseline serum UA levels might predict severity of CTD-PAH. Together with baseline values, changes of uric acid level may predict the clinical prognosis of the disease.


Assuntos
Doenças do Tecido Conjuntivo/complicações , Hipertensão Arterial Pulmonar/sangue , Ácido Úrico/sangue , Adulto , Biomarcadores/sangue , China , Doenças do Tecido Conjuntivo/diagnóstico , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Lineares , Masculino , Prognóstico , Hipertensão Arterial Pulmonar/etiologia , Hipertensão Arterial Pulmonar/mortalidade , Estudos Retrospectivos , Índice de Gravidade de Doença , Taxa de Sobrevida
6.
BMC Urol ; 18(1): 33, 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29739380

RESUMO

BACKGROUND: To observe the efficacy of self-help position therapy (SHPT) after holmium laser lithotripsy via flexible ureteroscopy (FURS). METHODS: From January 2010 to November 2015, 736 nephrolithiasis patients who had received FURS lithotripsy were analyzed retrospectively. In position group, 220 cases accepted SHPT after lithotripsies, and 428 cases as control, coming from another independent inpatient area in the same center. The stone-free status (SFS) between two groups were compared at the 2nd, 4th and 12th week ends by X-ray examinations. RESULTS: The preoperative incidence of hydronephrosis (25.9% vs. 18.0%, p = 0.018) or lower calyceal seeper (33.6% vs. 24.3%, p = 0.012) and the proportion of patients with > 2.0 cm stones (33.6% vs. 24.3%, p = 0.003) were all significantly higher in position group than in control group. There were no substantial difference between two groups in age, BMI, gender and medical histories. In postoperative followup, the incidence of hydronephrosis in position group was significantly lower than in control group (9.5% vs. 15.7%, p = 0.032) after removing double-J stents. In position group, the SFS of the 2nd week end (60.9% vs. 47.2%, p = 0.001), the 4th week end (74.1% vs. 62.8%, p = 0.004) and the 12th week end (86.9% vs. 79.4%, p = 0.021) were all significantly higher than those in control group. CONCLUSIONS: SHPT after holmium laser lithotripsy via FURS may increase postoperative SFS, accelerate stone fragment clearance, and decrease the incidence of hydronephrosis after removal of double-J stents. The therapy does not require professional assistance and is economical, simple, and effective.


Assuntos
Hólmio , Litotripsia a Laser/métodos , Nefrolitíase/terapia , Posicionamento do Paciente/métodos , Autocuidado/métodos , Ureteroscopia/métodos , Adulto , Feminino , Seguimentos , Humanos , Litotripsia a Laser/instrumentação , Masculino , Pessoa de Meia-Idade , Nefrolitíase/diagnóstico por imagem , Estudos Retrospectivos , Resultado do Tratamento , Ureteroscópios/estatística & dados numéricos , Ureteroscopia/instrumentação
7.
Healthcare (Basel) ; 12(16)2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39201191

RESUMO

Group-based trajectory modeling (GBTM) allows the trajectory analyses of repeated N-terminal pro-brain natriuretic peptide (NT-proBNP) measurements during follow-up visits of pulmonary artery hypertension associated with connective tissue disease (CTD-PAH) patients. This study aimed to (1) identify trajectories of NT-proBNP changing over time, (2) explore the association between NT-proBNP trajectories and prognosis, and (3) explore the effects of baseline clinical characteristics on NT-proBNP trajectories. A retrospective, single-centred, observational study was performed on 52 CTD-PAH patients who had undergone at least three follow-up visits within 1 year from baseline. Four NT-proBNP trajectories were identified using GBTM: low stability (n = 15, 28.85%), early remission (remission within 3 months) (n = 20, 38.46%), delayed remission (remission after 6 or 9 months) (n = 11, 21.15%), and high stability (n = 6, 11.54%). The low-stability and early-remission trajectories were related to a similar positive prognosis, while the delayed-remission and high-stability trajectories were associated with a gradually worsening prognosis (p = 0.000). Intensive CTD immunotherapy (corticosteroids plus immunosuppressants) was the only factor that remained significant after least absolute shrinkage and selection operator regression and multivariate logistic regression, and was independently associated with a lower risk NT-proBNP trajectory (p = 0.048, odds ratio = 0.027, 95% confidence interval: 0.001-0.963), which preliminarily indicated a benefit of CTD-PAH patients undergoing intensive CTD immunotherapy.

8.
ACS Omega ; 8(14): 13109-13117, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37065011

RESUMO

Cracking agents are indispensable and important products for national energy exploitation and large-scale infrastructure construction. Transient thermal expansion rock cracking agent is a new cracking agent product with excellent performance that has just appeared in recent years. However, it is still prepared by mechanical ball milling, which is considered not the best choice among traditional methods for preparing energetic materials. In this paper, a transient thermal expansion rock splitting agent was prepared by the chemical deposition method using carbon black and calcium peroxide as raw materials. The TG/DTG results show that the mass loss of the sample can be divided into four stages with the increase of temperature. It is worth noting that the mass loss of the TG curve of the sample during the entire thermal decomposition process is 93.385%, and the instantaneous weight loss is 78.07% (ß = 15 °C/min). Kinetic analysis of the thermal decomposition process of the samples was performed using an isotransformation program and a distributed activation energy model (DAEM). The activation energy E α of the thermal decomposition of the sample was iteratively calculated. The results show that the a-E a curve of the sample can be divided into two stages. The pyrolysis kinetics of the first stage was successfully analyzed by the DAEM method and its thermal conversion behavior was predicted. The thermal decomposition behavior of the second stage was analyzed by a traditional kinetic analysis method.

9.
RSC Adv ; 12(47): 30803-30816, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36349163

RESUMO

Red-light phosphors with extraordinary and stable thermal luminous properties must urgently be explored under the circumstances that commercial phosphors are suffering from serious thermal quenching effects and a lack of red-light components. Synthesized by a one-step hydrothermal method, a new type of NaYF4 : 0.065Eu3+,0.003Dy3+ phosphor with notable thermal luminous stability is reported in this study. As well as energy transfer between Dy3+ and Eu3+, this novel red-light phosphor manifests zero thermal quenching (ZTQ) performance under an increasing temperature of measurement. The ZTQ property stems from the interior defects of the crystal produced by the non-equivalence replacement between distinct ions. Density Functional Theory (DFT) calculations were utilized to verify the formation energy of two kinds of defects that make a vital contribution to the ZTQ performance of the NaYF4 : 0.065Eu3+,0.003Dy3+ phosphor. This finding could make some contributions towards research into improving thermal luminous properties and stability.

10.
RSC Adv ; 12(43): 27987-27995, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36320227

RESUMO

The luminescence properties and thermal stability of phosphors are key properties for practical applications. A series of K2SiF6: Mn4+, Na+ @ GQDs (KSF: Mn4+, Na+ @ GQDs, KSF = K2SiF6, GQDs = graphene quantum dots; here, Cl-contained graphene quantum dots are used) red light phosphors have been synthesized by using a combination of H2O2-free and hydrothermal coating methods. The fluorescence thermal stability and fluorescence intensity of the optimal phosphor are greatly improved by doping the matrix with Na+ and coating it with GQDs. The strong negative thermal quenching (NTQ) effect and the color stability of the phosphor at variable temperatures result in good thermal stability. The strong NTQ effect is attributed to the phonon-induced transition mechanism. The high thermal stability makes the optimal sample ideal for high-power light LEDs (WLEDs). The test results show that the prototype WLED with the optimal sample as the red light component produces warm white light. The light has high luminescent efficiency (101.6 lm W-1), low correlated color temperature (CCT = 3978 K), and high color rendering index (R a = 92.2).

11.
Dalton Trans ; 51(47): 18308-18316, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36413157

RESUMO

Mn4+-doped fluoride red light phosphors are widely utilized in various fields, and their luminous performance is influenced by their stability in high humidity and temperature environments. By incorporating TEOAH+ (TEOAH+ = (HOCH2CH2)3NH+) into the Na2TiF6 matrix, Na3HTiF8:Mn4+,TEOAH+ with improved thermal stability and water resistance was synthesized. Enhancement in the luminescence thermal stability is supported by its strong negative thermal quenching (NTQ) effect, which is attributed to the phonon-induced mechanism wherein the probability of radiative transitions increases much faster than the probability of non-radiative transitions. Additionally, the integrated emission intensity of the optimal sample Na3HTiF8:Mn4+,0.15TEOAH+ was maintained at 70.1% after being immersed in water for 360 min, which may be attributed to the addition of TEOAH+ cations in the structure, thus increasing its structural rigidity. The prototype light-emitting diode (LED) has a narrow emission band, 88.6% color gamut, and 83.1 lm W-1 light efficiency, according to the National Television Standards Committee (NTSC). The qualities of the phosphor make it an ideal candidate for back-lighting devices.

12.
RSC Adv ; 12(49): 31546-31554, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36380944

RESUMO

For the purpose of obtaining red-light phosphors with excellent luminescence thermal stability, a series of Gd4Al2O9:Eu3+ (GAO:Eu3+) phosphors were synthesized by combining the sol-gel method with high-temperature calcination, and a detailed series of study and analysis of their room temperature and high temperature luminescence properties was carried out. In GAO, the emission peaks corresponding to the 5D0 → 7F j (j = 0, 1, 2, 3 and 4) transitions of Eu3+ were observed at 578, 590, 610, 654, and 707 nm, with the strongest emission peak at 610 nm, and the obtained samples were red-light phosphors. The sample GAO:Eu3+ synthesized by combining the sol-gel method with high-temperature calcination has a negative thermal quenching (NTQ) effect, and the best doped sample GAO:0.16Eu3+ has an optimal luminescence temperature of 120 °C, and the corresponding integrated PL intensity is 183.2% of the initial value at 30 °C. The presence of the NTQ effect makes GAO:0.16Eu3+ have good luminescence thermal stability, which manifests as thermal-optical energy conversion at the macroscopic level. A detailed study of the thermal quenching mechanism was carried out.

13.
RSC Adv ; 12(7): 3788-3795, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35425405

RESUMO

A new type of monoethanolamine (MEA) and Mn4+ co-doped KTF : MEAH+, Mn4+ (K2TiF6 : 0.1MEAH+, 0.06Mn4+) red emitting phosphor was synthesized by an ion exchange method. The prepared Mn4+ co-doped organic-inorganic hybrid red phosphor exhibits sharp red emission at 632 nm and the emission intensity at room temperature is 1.43 times that of a non-hybrid control sample KTF : Mn4+ (K2TiF6 : 0.06Mn4+). It exhibits good luminescent thermal stability at high temperatures, and the maximum integrated PL intensity at 150 °C is 2.34 times that of the initial value at 30 °C. By coating a mixture of KTF : MEAH+, Mn4+, a yellow phosphor (YAG : Ce3+) and epoxy resin on a blue InGaN chip, a prototype WLED (white light-emitting diode) with CCT = 3740 K and R a = 90.7 is assembled. The good performance of the WLED shows that KTF : MEAH+, Mn4+ can provide a new choice for the synthesis of new Mn4+ doped fluoride phosphors.

14.
RSC Adv ; 13(1): 534-546, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36605632

RESUMO

Red phosphors with brilliant performance are crucial for the application of white LEDs as their red-light component. However, the thermal quenching phenomenon is an inevitable obstacle in the practical application of various types of red-light phosphors. In this study, we report the preparation of a novel type of phosphor, NaYF4: 0.065Eu3+, 0.002Sm3+, possessing not only an energy transfer effect from Sm3+ to Eu3+ but also superior negative thermal quenching (NTQ) performance. The phosphor was synthesized via a one-step hydrothermal method, resulting in a prominent improvement in its luminous thermal stability supported by NTQ. The NTQ originated from the thermal stimulation excitement of the captured electrons in electronic traps, which is attributed to the non-equivalence between the different types of ions. The shape of the emission spectrum measured at high temperature was identical to that measured at room temperature, which not only showed the remarkable thermal stability of this novel type of phosphor but also the promising prospect of its practical application. This finding will contribute to improving the thermal stability of phosphor materials doped with lanthanide elements.

15.
Clin Rheumatol ; 41(1): 255-264, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34387761

RESUMO

OBJECTIVES: Adiponectin (AD) highly expressed in synovial tissue correlates closely with progressive bone erosion in rheumatoid arthritis (RA). However, it remains unknown whether AD receptor mediates the pathogenesis of RA. This study aimed to investigate the effects of adiponectin receptor 1 (AdipoR1) signaling on synovial inflammation and joint damage in collagen-induced arthritis. METHODS: AD and AdipoR1 expression in synovial tissue of RA and osteoarthritis (OA) patients were tested by PCR and western blotting. The frequency of AdipoR1 on RA synovial fibroblasts (RASFs) was examined by flow cytometry after stimulation with AD, IL-6, or TNF-α. AdipoR1 was knocked down in human RASF cell line (MH7A) and CIA mice joints using lentiviral particles carrying the AdipoR1 short hairpin RNA (shAdipoR1). Both the proliferation and apoptosis of MH7A and the secretion of inflammatory factors from MH7A were examined in vitro. The therapeutic effect of local AdipoR1 inhibition on CIA mice was assessed in vivo. RESULTS: Both the expression of AD and AdipoR1 were significantly higher in RA synovial tissue. AdipoR1 on RASFs was upregulated by AD. Silencing AdipoR1 remarkably reduced lipopolysaccharides-induced proliferation and promoted the apoptosis of MH7A. Moreover, AdipoR1 knockdown inhibited the release of inflammatory factors in vitro. In CIA mice, local AdipoR1 inhibition effectively decreased joint inflammation and alleviated bone destruction via suppressing RANKL and RANKL/OPG ratio in vivo. CONCLUSIONS: AdipoR1 signaling participates in the process of synovial inflammation and joint damage in CIA. Local blockade of AdipoR1 might be a new target for the clinical treatment of RA. Key points • Local AdipoR1 inhibition decreased joint inflammation and alleviated bone destruction in CIA.


Assuntos
Artrite Experimental , Artrite Reumatoide , Receptores de Adiponectina/antagonistas & inibidores , Animais , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Fibroblastos , Humanos , Inflamação , Camundongos , Receptores de Adiponectina/genética , Transdução de Sinais , Membrana Sinovial
16.
RSC Adv ; 11(57): 36222-36229, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-35492796

RESUMO

In order to obtain a red emitting phosphor with good luminescence thermal stability, a series of KGdF4:Eu3+, Yb3+@GQD (GQD: Cl-containing graphene quantum dots) red emitting phosphors have been synthesized by the co-precipitation method, and their luminescence thermal properties have also been studied in detail. It is intriguing that the negative thermal quenching (NTQ) effect is induced by the double doping of Yb3+, and the effect is further enhanced by GQD coating. The strongest integrated PL intensities of the optimal double doped sample and the optimal GQD-coated sample are at 130 and 170 °C, in which the corresponding integrated PL intensities are presented as 117.7 and 156.5% of the initial value at 30 °C, respectively. The NTQ effect makes the optimal GQD coated sample have good luminescent thermal stability, so it can be applied for high-power WLEDs. A mechanism of energy conversion from heat to light is discussed and suggested for the effect.

17.
RSC Adv ; 11(37): 23023-23035, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35480463

RESUMO

Herein, a series of NSF:0.05Mn4+,0.04K+@GQD (NSF: Na2SiF6, GQDs: Cl-containing graphene quantum dot) phosphors was prepared. Double enhancement effects on the luminescent intensity and thermal stability triggered by the GQD coating were observed for the optimal sample as follows: (a) its PL intensity was 1.72 times that of the uncoated control sample and (b) its luminescent thermal stability was greatly enhanced, with integrated PL intensities of 120, 150 and 180 °C to 179.7%, 175.8%, and 119.3% of the initial value at 25 °C, respectively. It is proposed that the above-mentioned behaviors involve a change in some of the thermal energy into light energy via a phonon-induced mechanism. The thermal stability analysis results showed that the optimal sample is suitable for application in high-power WLEDs. Specifically, warm white light with a low correlated color temperature, high luminescent efficiency and high color rendering index was obtained from the prototype WLEDs using the optimal sample as a red-emitting component.

18.
Ultrasound Med Biol ; 47(4): 910-918, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33483161

RESUMO

The purpose of this study was to evaluate the role of 2-D speckle tracking imaging in assessing left ventricular diastolic function in patients with connective tissue disease (CTD). A total of 98 CTD patients and 32 healthy controls were prospectively recruited. Early (E) and late (A) diastolic velocities of the transmitral flow were measured by pulsed Doppler echocardiography. Peak early diastolic myocardial velocity (E') was calculated on tissue Doppler echocardiography. The longitudinal strain rate (SR) was calculated as the average of three apical views, while circumferential and radial SRs were measured in three short-axis views. Pulmonary arterial hypertension (PAH) was defined as systolic pulmonary arterial pressure (sPAP) >36 mm Hg. Compared with the control group, CTD patients exhibited significant impairment of left ventricular diastolic function, manifested as lower global SR during early diastole (SRe) in the longitudinal deformation and higher E/SRe in both longitudinal and radial deformation. CTD-PAH patients had significantly lower SRe and higher E/SRe values in both the longitudinal and radial deformation compared with the patients with CTD without PAH. Pearson's correlation analysis revealed that sPAP levels correlated positively with E/E', longitudinal E/SRe, circumferential E/SRe and radial SRe, and it correlated negatively with septal E' and radial E/SRe. Receiver operating characteristic curve analysis suggested that E/E', longitudinal E/SRe and radial SRe could be used to predict PAH. The present study indicates that 2-D speckle tracking imaging is a useful method for evaluation of left ventricular diastolic function, and these derived parameters can serve as good predictors of PAH, but it may not be superior to the commonly used E/E' in CTD patients.


Assuntos
Doenças do Tecido Conjuntivo/fisiopatologia , Ecocardiografia/métodos , Hipertensão Arterial Pulmonar/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Adulto , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Doenças do Tecido Conjuntivo/complicações , Diástole , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Prospectivos , Hipertensão Arterial Pulmonar/etiologia , Curva ROC , Reprodutibilidade dos Testes , Disfunção Ventricular Esquerda/etiologia
19.
Clin Rheumatol ; 38(12): 3619-3626, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31385084

RESUMO

OBJECTIVE: To explore the long-term prognostic value of a simplified risk assessment strategy based on the 2015 European Society of Cardiology (ESC)/European Respiratory Society (ERS) pulmonary hypertension (PH) guidelines in Chinese patients with connective tissue disease (CTD) associated with pulmonary arterial hypertension (PAH). METHODS: We identified 50 CTD-PAH patients diagnosed by right heart catheterization. A retrospective chart review was completed to assess their clinical presentation and laboratory test results. A simplified version of the risk stratification model proposed by the 2015 ESC/ERS PH guidelines was applied, which included the WHO functional class, the 6-minute walking distance test, N-terminal pro-B-type natriuretic peptide plasma levels, pericardial effusion, right atrial pressure (RAP), cardiac index (CI), and mixed venous oxygen saturation (SvO2). The risk grades were defined as follows: low risk = at least 3 low-risk variables and no high-risk variables; high risk = at least 2 high-risk variables, including SvO2 or CI; and intermediate risk = when the above definitions of low or high risk were not fulfilled. The study endpoint was 3-year all-cause mortality. RESULTS: Twenty patients were defined as a low-risk group, while 30 were classified into a combined intermediate-high-risk group at the baseline assessment. All 20 patients in the low-risk group remained in the low-risk group at follow-up, 20 patients in the intermediate-high-risk group were downgraded to the low-risk group, and eight patients remained in the intermediate-high-risk group at the follow-up assessment. Patients in the intermediate-high-risk group exhibited higher 3-year mortality than the low-risk group at baseline (26% vs 14%, P = 0.0384). Compared with patients who remained in the intermediate-high-risk group, patients who were downgraded to the low-risk group showed lower 3-year mortality (P = 0.0281). CONCLUSION: A simplified risk stratification model based on the 2015 ESC/ERS PH guidelines helped to identify CTD-PAH patients with poor long-term  prognosis , which was useful in evaluating the severity and treatment response of patients with CTD-PAH.Key Point•This study showed that the simplified version of the 2015 ESC/ERS risk stratification model could help identify Chinese CTD-PAH patients with poor prognosis at diagnosis and after treatment initiation.


Assuntos
Doenças do Tecido Conjuntivo/complicações , Hipertensão Arterial Pulmonar/etiologia , Adulto , China/epidemiologia , Feminino , Humanos , Masculino , Hipertensão Arterial Pulmonar/mortalidade , Estudos Retrospectivos , Medição de Risco
20.
Zhongguo Zhen Jiu ; 35(5): 493-6, 2015 May.
Artigo em Chinês | MEDLINE | ID: mdl-26255529

RESUMO

Renying and cunkou pulse diagnostic methods have been recorded in Neijing Unternal Classic) and Maijing (Pulse Classic) and these two pulse diagnostic methods are very different. Through the analysis and inference on the relevant statements in Internal Classic and Pulse Classic, as well as those of medical scholars in later generations, it is discovered that the pulse of excess type, the pulse of deficiency type, the tense pulse, the regular missed-beat pulse, etc. could be detected and be used to judge the disorders of meridians and zangfu organs by the comparison between the pulse of excess type and the pulse of deficiency type with renying and cunkou pulse diagnostic methods recorded in Internal Classic. The substance of renying and cunkou pulse diagnostic methods in Pulse Classic is consistent with the methods in later generations, meaning that they can be applied to judge the disorders of meridians and zangfu organs through detecting the excess or the deficiency in every region of cun, guan and chi.


Assuntos
Técnicas e Procedimentos Diagnósticos/história , Frequência Cardíaca , China , Técnicas e Procedimentos Diagnósticos/instrumentação , História Antiga , Humanos , Medicina na Literatura , Meridianos
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