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1.
Front Physiol ; 14: 1126780, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36875027

RESUMEN

Purpose: We aim to present effective and computer aided diagnostics in the field of ophthalmology and improve eye health. This study aims to create an automated deep learning based system for categorizing fundus images into three classes: normal, macular degeneration and tessellated fundus for the timely recognition and treatment of diabetic retinopathy and other diseases. Methods: A total of 1,032 fundus images were collected from 516 patients using fundus camera from Health Management Center, Shenzhen University General Hospital Shenzhen University, Shenzhen 518055, Guangdong, China. Then, Inception V3 and ResNet-50 deep learning models are used to classify fundus images into three classes, Normal, Macular degeneration and tessellated fundus for the timely recognition and treatment of fundus diseases. Results: The experimental results show that the effect of model recognition is the best when the Adam is used as optimizer method, the number of iterations is 150, and 0.00 as the learning rate. According to our proposed approach we, achieved the highest accuracy of 93.81% and 91.76% by using ResNet-50 and Inception V3 after fine-tuned and adjusted hyper parameters according to our classification problem. Conclusion: Our research provides a reference to the clinical diagnosis or screening for diabetic retinopathy and other eye diseases. Our suggested computer aided diagnostics framework will prevent incorrect diagnoses caused by the low image quality and individual experience, and other factors. In future implementations, the ophthalmologists can implement more advanced learning algorithms to improve the accuracy of diagnosis.

2.
Toxicol Res (Camb) ; 11(3): 498-510, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35782639

RESUMEN

Dezocine, a dual agonist and antagonist of the µ-opioid receptor and κ-opioid receptor, is widely used as an analgesic in China. At present, there are few studies on anti-tumor effects of dezocine, most of which are used to treat cancer pain. However, it has recently been reported that dezocine can induce apoptosis of triple negative breast cancer cells. Dezocine may have some anti-tumor activity, but the effect and potential mechanism of dezocine in the treatment of other types of cancer remain to be fully studied. The purpose of the present study was to investigate the effect of dezocine on human Hela cervical carcinoma cells, and to elucidate the underlying molecular mechanisms. We performed CCK-8 assays, clone formation assays, xenograft, flow cytometry analysis, western blot and RNA-seq analysis to evaluate the effects of dezocine on Hela cells. In addition, the role of endoplasmic reticulum (ER) stress in dezocine-induced apoptosis was investigated using qPCR and western blot analysis. Dezocine inhibited Hela cell viability in dose-dependent and time-dependent manners, and notably did not achieve this effect by targeting the opioid receptors. Further mechanistic studies demonstrated that dezocine activated ER stress by upregulating the expression of GRP78, IRE1 and p-JNK, and that dezocine-induced apoptosis was attenuated when the ER stress pathway was blocked. Our results provide a foundation to support the redefinition of dezocine as a novel, adjuvant treatment for patients with cervical cancer, although further research will be required to support its application in clinical practice.

3.
Org Biomol Chem ; 20(9): 1969-1973, 2022 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-35175267

RESUMEN

A method of direct C-4 selective alkylation of pyridines under visible light irradiation at room temperature has been reported, using simple maleate-derived pyridinium salts as pyridine precursors and the readily available carboxylic acid-derived N-(acyloxy)phthalimides as alkyl radical precursors, affording good to excellent yields without using stoichiometric oxidants and acids. A broad range of primary, secondary, and tertiary carboxylates can be used as alkylation reagents. Oxidant and acid-sensitive functional groups can be tolerated well.

4.
Vascular ; 30(5): 943-951, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34311590

RESUMEN

BACKGROUND: It is indicated that Low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio (LDL-C/HDL-C ratio) has greater predictive value for thickened carotid intima-media thickness (CIMT) comparing with classic lipid parameters. However, there have been few reports about their association in general Chinese population. METHOD: We included a total of 1220 CIMT participants and 2440 matched controls, who had ultrasonography of carotid artery during 2009 and 2016. Univariate and multivariate logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for thickened CIMT risk associated with LDL-C/HDL-C ratio. RESULT: In the univariate logistic regression model, there was significant association between LDL-C/HDL-C ratio and thickened CIMT (Q4 vs. Q1, OR = 1.94, 95% CI: 1.60-2.36; ptrend < 0.05). After adjusting for potential covariates, LDL-C/HDL-C ratio remained significantly associated with thickened CIMT (Q4 vs. Q1, OR = 1.81, 95% CI: 1.41-2.34, ptrend < 0.001; ≥3.05 v.s. <3.05, OR = 1.66, 95% CI: 1.37-2.02). In subgroup analyses, the association between LDL-C/HDL-C ratio and thickened CIMT remained significant in the subgroups stratified by sex, impaired fasting glucose (IFG), hypertension, and fatty liver disease but only remained significant in the subgroups of ≥45 years (OR = 2.01, 95% CI: 1.46-2.76; Ptrend<0.05), BMI ≥24 (kg/m2) (OR = 2.22; 95% CI = 1.63-3.03; Ptrend < 0.05) and BMI ≥25 (kg/m2) (OR = 2.50, 95% CI: 1.76-3.54; Ptrend < 0.05), dyslipidemia (OR = 3.28, 95% CI: 1.83-5,85; Ptrend < 0.001), and without periodontitis (OR = 2.08, 95% CI: 1.54-2.81 ; Ptrend < 0.05) comparing Q4 to Q1. Similar results were observed in the subgroup analyses for LDL-C/HDL-C ratio ≥3.05 v.s. <3.05 except for the age stratification. CONCLUSION: High LDL-C/HDL-C ratio could significantly increase the risk of thickened CIMT independent of gender, IFG, hypertension, and fatty liver disease in general Chinese population.


Asunto(s)
Hipertensión , Hepatopatías , Arterias Carótidas/diagnóstico por imagen , Grosor Intima-Media Carotídeo , Estudios de Casos y Controles , HDL-Colesterol , LDL-Colesterol , Glucosa , Humanos , Factores de Riesgo
5.
Opt Express ; 28(3): 2732-2743, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-32121955

RESUMEN

Entanglement and quantum squeezing have wide applications in quantum technologies due to their non-classical characteristics. Here we study entanglement and quantum squeezing in an open spin-optomechanical system, in which a Rabi model (a spin coupled to the mechanical oscillator) is coupled to an ancillary cavity field via a quadratic optomechanical coupling. We find that their performances can be significantly modulated via the photon of the ancillary cavity, which comes from photon-dependent spin-oscillator coupling and detuning. Specifically, a fully switchable spin-oscillator entanglement can be achieved, meanwhile a strong mechanical squeezing is also realized. Moreover, we study the environment-induced decoherence and dissipation, and find that they can be mitigated by increasing the number of photons. This work provides an effective way to manipulate entanglement and quantum squeezing and to suppress decoherence in the cavity quantum electrodynamics with a quadratic optomechanics.

6.
Opt Express ; 26(9): 11915-11927, 2018 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-29716108

RESUMEN

Quantum squeezing, as a typical quantum effect, is an important resource for many applications in quantum technologies. Here we propose a scheme for generating quantum squeezing, including the ponderomotive squeezing and the mechanical squeezing, in an optomechanical system, in which the radiation-pressure coupling and the mechanical spring constant are modulated periodically. In this system, the radiation-pressure interaction can be enhanced remarkably by the modulation-induced mechanical parametric amplification. Moreover, the effective phonon noise can be suppressed completely by introducing a squeezed vacuum reservoir. This ultimately leads to that our scheme can achieve a controllable quantum squeezing. Numerical calculations show that our scheme is experimentally realizable with current technologies.

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