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1.
Exp Eye Res ; : 107972, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32059975

RESUMO

Autophagy plays critical roles in various ocular diseases, including age-related macular degeneration (AMD). Tie2-expressing macrophages (TEMs) play crucial roles in angiogenesis. To investigate the role of TEMs and autophagy in the development of AMD, we employed macrophage-specific Tie2 knockout mice and used a laser-induced choroidal neovascularization (CNV). The results showed that TEMs can promote CNV formation by up-regulating the level of autophagy. These results were further verified by in vitro cell experiments that peritoneal macrophages from Tie2 knockout mice can inhibit the expression of autophagy-related factors and inhibit the expression of angiogenic factor of VEGF by activating AMPK signaling pathway. Our results suggest that TEMs and macrophage Tie2 signal mediated-autophagy play critical role in experimental CNV, and they may be novel preventive targets for AMD treatment.

3.
Front Chem ; 7: 715, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31709238

RESUMO

Gold nanorods (GNRs) has been investigated in the field of chemistry, optoelectronics, and medicine for their tenability, compatibility, electromagnetics, and excellent photonics properties. Especially, GNRs, used to generate ultrashort pulse, have been studied recently. However, multiple pulses evolution based on GNRs needs to be further explored. In this article, GNRs are synthesized by seed-mediated growth method, characterized systematically and been chosen as saturable absorber (SA) to apply in ultrafast photonics. The GNRs SA presents a saturable intensity of 266 MW/cm2, modulation depth of 0.6%, and non-saturable loss of 51%. Furthermore, a passively mode-locked erbium-doped fiber laser based on GNRs SA with femtosecond pulse is demonstrated. Thanks to the excellent properties of GNRs, by adjusting the cavity polarization direction with the proposed GNRs SA, soliton molecules operation with spectrum modulation period of 3.3 nm and pulse modulation interval of 2.238 ps is directly obtained. For the most important, 9th-order harmonic soliton molecules have been generated in the laser cavity for the first time. It is demonstrated that GNRs can be a novel type of non-linear optical (NLO) device and have potential applications in the field of ultrafast photonics.

4.
Nat Commun ; 10(1): 4062, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492855

RESUMO

The growth and wetting of water on two-dimensional(2D) materials are important to understand the development of 2D material based electronic, optoelectronic, and nanomechanical devices. Here, we visualize the liquefaction processes of water on the surface of graphene, MoS2 and black phosphorus (BP) via optical microscopy. We show that the shape of the water droplets forming on the surface of BP, which is anisotropic, is elliptical. In contrast, droplets are rounded when they form on the surface of graphene or MoS2, which do not possess orthometric anisotropy. Molecular simulations show that the anisotropic liquefaction process of water on the surface of BP is attributed to the different binding energies of H2O molecules on BP along the armchair and zigzag directions. The results not only reveal the anisotropic nature of water liquefaction on the BP surface but also provide a way for fast and nondestructive determination of the crystalline orientation of BP.

5.
Comput Methods Programs Biomed ; 178: 163-173, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31416545

RESUMO

BACKGROUND AND OBJECTIVE: Wheezing is a common symptom of patients caused by asthma and chronic obstructive pulmonary diseases. Wheezing detection identifies wheezing lung sounds and helps physicians in diagnosis, monitoring, and treatment of pulmonary diseases. Different from the traditional way to detect wheezing sounds using digital image process methods, automatic wheezing detection uses computerized tools or algorithms to objectively and accurately assess and evaluate lung sounds. We propose an innovative machine learning-based approach for wheezing detection. The phases of the respiratory sounds are separated automatically and the wheezing features are extracted accordingly to improve the classification accuracy. METHODS: To enhance the features of wheezing for classification, the Adaptive Multi-Level In-Exhale Segmentation (AMIE_SEG) is proposed to automatically and precisely segment the respiratory sounds into inspiratory and expiratory phases. Furthermore, the Enhanced Generalized S-Transform (EGST) is proposed to extract the wheezing features. The highlighted features of wheezing improve the accuracy of wheezing detection with machine learning-based classifiers. RESULTS: To evaluate the novelty and superiority of the proposed AMIE_SEG and EGST for wheezing detection, we employ three machine learning-based classifiers, Support Vector Machine (SVM), Extreme Learning Machine (ELM) and K-Nearest Neighbor (KNN), with public datasets at segment level and record level respectively. According to the experimental results, the proposed method performs the best using the KNN classifier at segment level, with the measured accuracy, sensitivity, specificity as 98.62%, 95.9% and 99.3% in average respectively. On the other aspect, at record level, the three classifiers perform excellent, with the accuracy, sensitivity, specificity up to 99.52%, 100% and 99.27% respectively. We validate the method with public respiratory sounds dataset. CONCLUSION: The comparison results indicate the very good performance of the proposed methods for long-term wheezing monitoring and telemedicine.

6.
Clin Ophthalmol ; 13: 1341-1352, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31440022

RESUMO

Purpose: To study the distribution of posterior corneal astigmatism (PCA) and its influencing factors in Chinese patients before cataract surgery. Patients and methods: A retrospective study was conducted in the First Affiliated Hospital of Soochow University, Suzhou, China. In all, this study enrolled 121 eligible eyes of 121 cataract patients. The astigmatism, aberrations and Q value of anterior, posterior and total cornea and anterior segment parameters (ACD, CCT, WTW, ATA) were measured by the Sirius System, and AL was measured by Lenstar LS 900. Cataract was diagnosed using slit-lamp examination. Results: The mean age of patients was 67.44±10.66 years old. Mean PCA was 0.31±0.17 (range 0.05-1.09) D and 85.9% eyes had PCA values <0.5 D. With-the-rule (WTR) astigmatism predominated the anterior cornea astigmatism (ACA) (48.8%) and total corneal astigmatism (TCA) (61.2%), while against-the-rule (ATR) astigmatism predominated posterior (86.0%). Significant positive correlation was found between the astigmatic power vector (APV) of ACA and PCA (Pearson correlation=0.318, P<0.001); TCA and PCA (Pearson correlation=0.204, P=0.025); keratometric astigmatism and PCA (Pearson correlation=0.356, P<0.001); this study also found a positive correlation between primary spherical aberration (Z4°) of the total cornea and PCA (Pearson correlation=0.266, P=0.003); primary spherical aberration (Z4°) of the corneal front surface and PCA (Pearson correlation=0.260, P=0.004); total corneal aberrations (Total cornea root mean square [RMS]) and PCA (Pearson correlation=0.327, P<0.001); total corneal higher-order aberrations (Total HOA RMS) (Pearson correlation=0.232, P=0.011); total corneal lower-order aberrations (Total LOA RMS) (Pearson correlation=0.250, P=0.006). A positive linear correlation between Q value of corneal front surface and PCA, either 6 mm pupil diameter (Pearson correlation=0.264, P=0.003) or 8 mm pupil diameter (Pearson correlation=0.184, P=0.043) was found in this study. Conclusion: Corneal aberration, Q value (front surface specifically) was essential that we need to take into consideration when we conduct PCA and intraocular lens measurement in clinics.

7.
BMC Ophthalmol ; 19(1): 161, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31349817

RESUMO

BACKGROUND: Persistent hyperplastic primary vitreous (PHPV) is a rare congenital developmental ocular disorder caused by incomplete regression of the embryonic hyaloid vasculature. Here we report a case of nonsurgical unilateral anterior PHPV that was managed by amblyopia treatment and resulted in an improvement of visual acuity and regression of the fetal vasculature. CASE PRESENTATION: A three-year-old girl was diagnosed with unilateral anterior PHPV in the left eye, manifested with posterior pole cataract, posterior capsule opacification, tunica vasculosa lentis, and a floating hyaloid artery connected to the retrolental mass. The plaque was not large enough to fill the pupil, and conservative management along with amblyopia treatment was conducted. Nineteen months later, the visual acuity in the affected eye improved from 20/100 to 20/50 with correction, and the fetal vasculature regressed gradually and finally into a nonperfusion ghost vessel. CONCLUSIONS: In PHPV-affected children, regression of the fetal vasculature may be observed, and conservative management and amblyopia treatment may be helpful for visual improvement.


Assuntos
Tratamento Conservador/métodos , Vítreo Primário Hiperplásico Persistente/diagnóstico , Recuperação de Função Fisiológica , Acuidade Visual/fisiologia , Corpo Vítreo/anormalidades , Pré-Escolar , Progressão da Doença , Óculos , Feminino , Seguimentos , Humanos , Vítreo Primário Hiperplásico Persistente/fisiopatologia , Vítreo Primário Hiperplásico Persistente/terapia , Privação Sensorial , Corpo Vítreo/diagnóstico por imagem
8.
Small ; 15(23): e1900902, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31016874

RESUMO

Non-layered tellurium (Te) is a promising material for applications in transistor and optoelectronic devices for its advantages in excellent intrinsic electronic and optoelectronic properties. However, the poor photodetection performance and relatively uncertain stability of tellurene under ambient conditions greatly limit the practical applications. In order to improve the performance of tellurene-based materials, Te@Se roll-to-roll nanotubes with different selenium (Se) contents synthesized by epitaxial growth of Se on Te nanotubes are, for the first time, employed to fabricate working electrodes for photoelectrochemical (PEC)-type broadband photodetection. They exhibit not only a preferably enhanced capacity for self-powered broadband photodetection but also significantly improved photocurrent density and stability in various aqueous environments (HCl, NaCl, and KOH solutions), compared to tellurene-based photodetectors. It is anticipated that the present work can open up new possibilities for high-performance tellurene-based optoelectronic devices.

9.
ACS Med Chem Lett ; 10(3): 312-317, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30891132

RESUMO

A triazine hit identified from a screen of the BMS compound collection was optimized for potency, in vivo activity, and off-target profile to produce the bicyclic pyrimidine γ-secretase modulator BMS-932481. The compound showed robust reductions of Aß1-42 and Aß1-40 in the plasma, brain, and cerebrospinal fluid of mice and rats. Consistent with the γ-secretase modulator mechanism, increases in Aß1-37 and Aß1-38 were observed, with no change in the total amount of Aß1-x produced. No Notch-based toxicity was observed, and the overall preclinical profile of BMS-932481 supported its further evaluation in human clinical trials.

10.
Acta Diabetol ; 56(8): 823-837, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30900027

RESUMO

AIMS: Diabetic retinopathy (DR) is an important microvascular complication of diabetes mellitus (DM) and a leading cause of visual impairment and blindness among people of working age. Physical activity (PA) or exercise is critical and beneficial for DM patients, whereas studies evaluating the relationship between PA and DR have yielded inconsistent and inconclusive results. The American Diabetes Association's "Standards of Medical Care in Diabetes" has also pointed out the indeterminate roles of PA in DR prevention. The purpose of this systematic review and meta-analysis was to explore the association between PA and DR risk. METHODS: Medline (accessed by PubMed), EmBase, and Cochrane Library were systematically searched for studies up to June 2018, and the reference lists of the published articles were searched manually. The association between PA and DR risk was assessed using random-effect meta-analysis. RESULTS: Twenty-two studies were included in this meta-analysis. PA was found to have a protective association with DR [risk ratio (RR) = 0.94, 95% confidence interval (95% CI) 0.90-0.98, p = 0.005] in diabetic patients, and the impact was more pronounced on vision-threatening DR (RR = 0.89, 95% CI 0.80-0.98, p = 0.02). Sedentary behavior could increase the risk of DR (RR = 1.18, 95% CI 1.01-1.37, p = 0.04). Moderate-intensity PA was likely to have a slight protective effect (RR = 0.76, 95% CI 0.58-1.00, p = 0.05). CONCLUSION: PA is associated with lower DR risk, and more studies should focus on the causality between them.


Assuntos
Retinopatia Diabética/epidemiologia , Exercício , Humanos , Comportamento Sedentário
11.
J Med Chem ; 62(7): 3228-3250, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30893553

RESUMO

Bruton's tyrosine kinase (BTK), a non-receptor tyrosine kinase, is a member of the Tec family of kinases and is essential for B cell receptor (BCR) mediated signaling. BTK also plays a critical role in the downstream signaling pathways for the Fcγ receptor in monocytes, the Fcε receptor in granulocytes, and the RANK receptor in osteoclasts. As a result, pharmacological inhibition of BTK is anticipated to provide an effective strategy for the clinical treatment of autoimmune diseases such as rheumatoid arthritis and lupus. This article will outline the evolution of our strategy to identify a covalent, irreversible inhibitor of BTK that has the intrinsic potency, selectivity, and pharmacokinetic properties necessary to provide a rapid rate of inactivation systemically following a very low dose. With excellent in vivo efficacy and a very desirable tolerability profile, 5a (branebrutinib, BMS-986195) has advanced into clinical studies.

12.
Sci Rep ; 9(1): 3137, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30816322

RESUMO

Early detection of diabetic microvascular complications is of great significance for disease prognosis. This systematic review and meta-analysis aimed to investigate the correlation among diabetic microvascular complications which may indicate the importance of screening for other complications in the presence of one disorder. PubMed, Embase, and the Cochrane Library were searched and a total of 26 cross-sectional studies met our inclusion criteria. Diabetic retinopathy (DR) had a proven risk association with diabetic kidney disease (DKD) [odds ratio (OR): 4.64, 95% confidence interval (CI): 2.47-8.75, p < 0.01], while DKD also related to DR (OR: 2.37, 95% CI: 1.79-3.15, p < 0.01). In addition, DR was associated with diabetic neuropathy (DN) (OR: 2.22, 95% CI: 1.70-2.90, p < 0.01), and DN was related to DR (OR: 1.73, 95% CI: 1.19-2.51, p < 0.01). However, the risk correlation between DKD and DN was not definite. Therefore, regular screening for the other two microvascular complications in the case of one complication makes sense, especially for patients with DR. The secondary results presented some physical conditions and comorbidities which were correlated with these three complications and thus should be paid more attention.

13.
Adv Mater ; 31(14): e1807981, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30730064

RESUMO

Graphdiyne is a new carbon allotrope comprising sp- and sp2 -hybridized carbon atoms arranged in a 2D layered structure. In this contribution, 2D graphdiyne is demonstrated to exhibit a strong light-matter interaction with high stability to achieve a broadband Kerr nonlinear optical response, which is useful for nonreciprocal light propagation in passive photonic diodes. Furthermore, advantage of the unique Kerr nonlinearity of 2D graphdiyne is taken and a nonreciprocal light propagation device is proposed based on the novel similarity comparison method. Graphdiyne has demonstrated a large nonlinear refractive index in the order of ≈10-5 cm2 W-1 , comparing favorably to that of graphene. Based on the strong Kerr nonlinearity of 2D graphdiyne, a nonlinear photonic diode that breaks time-reversal symmetry is demonstrated to realize the unidirectional excitation of Kerr nonlinearity, which can be regarded as a significant demonstration of a graphdiyne-based prototypical application in nonlinear photonics and might suggest an important step toward versatile graphdiyne-based advanced passive photonics devices in the future.

14.
R Soc Open Sci ; 6(1): 181090, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30800362

RESUMO

A new red fluorescent probe 1 based on BODIPY skeleton has been successfully synthesized through introduction of 2-(thiophen-2-yl) quinoline moiety at meso- and 3-position, which exhibits excellent optical performance, including high fluorescence quantum yield, large pseudo Stokes' shift as well as high selectivity and sensitivity towards iridium (III) ion in aqueous solution and in living cells.

15.
Nanoscale ; 11(6): 2637-2643, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30698602

RESUMO

In this work, 0-dimensional (0D) CsPbBr3 QDs were integrated with 2D bismuthene having ultrafast carrier mobility, to obtain a 0D/2D nanohybrid. Moreover, an excellent charge transfer efficiency (0.53) and an appreciable quenching constant of 2.3 × 105 M-1 were observed. Tuning the ratio of bismuthene in the Bi/perovskite nanohybrid achieved the quantified control of charge transfer efficiency and quenching performance at the interface.

16.
ACS Appl Mater Interfaces ; 11(4): 4278-4287, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30623664

RESUMO

Owing to the attractive energy band properties, a black phosphorus (BP)-analogue semiconductor, germanium selenide (GeSe), shows a promising potential applied for optoelectronic devices. Herein, ultrathin GeSe nanosheets were systematically prepared via a facile liquid-phase exfoliation approach, with controllable nanoscale thickness. Different from BP, ultrathin GeSe nanosheets exhibit good stability under both liquid and ambient conditions. Besides, its ultrafast carrier dynamics was probed by transient absorption spectroscopy. We showed that the GeSe nanosheet-based photodetector exhibits excellent photoresponse behaviors ranging from ultraviolet (UV) to the visible regime, with high responsivity and low dark current. Furthermore, the detective ability of such a device can be effectively modulated by varying the applied bias potential, light intensity, and concentration of the electrolyte. Generally, our present contribution could not only supply fundamental knowledge of a GeSe nanosheet-based photoelectrochemical (PEC)-type device, but also offer guidance to extend other possible semiconductor materials in the application of the PEC-type photodetector.

17.
IEEE J Biomed Health Inform ; 23(3): 1163-1170, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-29994776

RESUMO

Speech is easily affected by different background noise in real environment to reduce the speech intelligibility, in particular, for hearing impaired listeners. In order to improve the above issue, several hearing aids have been developed to enhance the speech signal in noisy environment. Most of current hearing aids were designed to enhance the component of speech and suppress the component of noise. However, it is difficult to separate other speech sources. Adaptive signal enhancement with the beamforming technique might improve the above issue. However, how to distinguish the location of the desired speaker effectively is still a difficult challenge for adaptive beamforming method. A novel concept of hearing aid was proposed in this study. Different from the beamforming-based hearing aids, which use the cross-correlation-coefficient method to estimate time difference of arrival (TDOA), an image recognition technology was used to estimate the location of the desired speaker to obtain the more precise TDOA. An adaptive signal enhancement was also used to enhance the noisy speech sound. From the experimental results, the proposed system could provide a smaller absolute error of TDOA less than 1.25 × 10-4 ms, and a clear speech sound from the target speaker who the user wants to listen to.


Assuntos
Auxiliares de Audição , Processamento de Imagem Assistida por Computador/métodos , Processamento de Sinais Assistido por Computador/instrumentação , Espectrografia do Som/métodos , Algoritmos , Humanos , Ruído , Fala/fisiologia
18.
Medicine (Baltimore) ; 97(48): e13251, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30508911

RESUMO

BACKGROUND: Successful labor induction depends on the cervical status at the time of induction. Currently, both a Foley catheter and a dinoprostone insert are used for effective cervical ripening. This study compared the efficacy and safety of the intracervical Foley catheter and dinoprostone insert for cervical ripening to achieve successful labor induction. METHODS: PubMed, Embase, and the Cochrane Library were searched from January 2000 to February 2017 for relevant articles. Only published randomized, controlled trials comparing the dinoprostone insert with the Foley catheter were included. RESULTS: Eight trials including 1191 women who received the intracervical Foley catheter balloon and 1199 who received the dinoprostone insert were used for this study. There was no significant difference between the 2 groups regarding the induction-to-delivery (I-D) interval in a random effect model (mean difference, 0.71 hours; 95% confidence interval [CI], -2.50 to 3.91; P = .67). The highly significant heterogeneity (I = 97%) could be explained by the subgroup analysis of the type of Foley catheter and balloon volume. There was no significant difference between the 2 methods regarding the cesarean delivery rate (relative risk, 0.91; 95% CI, 0.78-1.07; P = .24), Apgar score, or side effects, including maternal infection rate, postpartum hemorrhage, and hyperstimulation. No obvious publication bias was found. CONCLUSIONS: According to the cesarean delivery rate, the intracervical Foley catheter balloon was as efficient as the dinoprostone insert. A moderate balloon volume (30 mL) and higher dose of dinoprostone (≥6 mg) were related to shorter I-D intervals. Additionally, there was no significant difference between the two methods regarding maternal or neonatal safety.


Assuntos
Cateteres , Maturidade Cervical/efeitos dos fármacos , Dinoprostona/administração & dosagem , Trabalho de Parto Induzido/métodos , Ocitócicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Trabalho de Parto Induzido/instrumentação , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
J Ophthalmol ; 2018: 1425707, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30425852

RESUMO

Purpose: Intravitreal antivascular endothelial growth factor (anti-VEGF) therapy has been widely used for the treatment of neovascularization (NV) secondary to age-related macular degeneration (AMD). This study aimed to compare the efficacy among different subtypes of neovascular age-related macular degeneration (nAMD). Methods: PubMed, Embase, and the Cochrane Library were searched for eligible studies. We performed meta-analysis using Review Manager 5.3 and Stata/SE 12.0. Results: A total of 24 studies met our inclusion criteria and were included in the systematic review. At 3 months, the mean logarithm of the minimum angle of resolution (logMAR) improvements were -0.09, -0.18, and -0.23 for type 1, 2, and 3, respectively, while the mean macular thickness (MT) changes were -104.83, -130.76, and -196.29 µm. At 12 months, the mean changes in Early Treatment of Diabetic Retinopathy Study (ETDRS) letters were 6.38, 8.12, and 9.37, while the MT decrease was 126.51, 126.52, and 139.85 µm, respectively. However, statistically significant difference was only found between type 1 and 3 in vision improvement, both in the short term (p=0.0002) and long term (p=0.01). Conclusions: The reactivity to VEGF inhibitors varied among different subtypes of nAMD. The efficacy of intravitreal anti-VEGF therapy in type 3 nAMD was statistically better than type 1 when considering vision improvement at 3 and 12 months. Thus, the lesion subtype is a predictor for the treatment outcome which can help guide prognosis.

20.
Nanoscale ; 10(44): 20540-20547, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30402631

RESUMO

In recent years, black-phosphorus-analogue (BPA) two-dimensional (2D) materials have been explored to demonstrate promising optoelectronic performances and distinguished ambient stabilities, holding great promise in practical applications. Here, one new kind of BPA material, orthorhombic ß-PbO quantum dots (QDs), is successfully fabricated by a facile liquid phase exfoliation (LPE) technique. The as-prepared ß-PbO QDs show a homogeneous distribution of the lateral size (3.2 ± 0.9 nm) and thickness (2.5 ± 0.5 nm), corresponding to 4 ± 1 layers. The carrier dynamics of ß-PbO QDs was systematically investigated via a femtosecond resolution transient absorption approach in the visible wavelength regime and it was clarified that two decay components were resolved with a decay time of τ1 = 2.3 ± 0.3 ps and τ2 = 87.9 ± 6.0 ps, respectively, providing important insights into their potential applications in the field of ultrafast optics, nanomechanics and optoelectronics. As a proof-of-concept, ß-PbO QDs were, for the first time to our knowledge, fabricated as a working electrode in a photoelectrochemical (PEC)-typed photodetector that exhibits significantly high photocurrent density and excellent stability under ambient conditions.

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