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1.
Micromachines (Basel) ; 15(4)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38675350

RESUMO

This study presents a numerical simulation-based investigation of a MEMS (micro-electromechanical systems)technology-based deformable mirror employing a piezoelectric film for fundus examination in adaptive optics. Compared to the classical equal-area electrode arrangement model, we optimize the electrode array for higher-order aberrations. The optimized model centralizes electrodes around the mirror center, which realizes low-voltage driving with high-accuracy correction. The optimized models exhibited commendable correction abilities, achieving a unidirectional displacement of 5.74 µm with a driven voltage of 15 V. The voltage-displacement relationship demonstrated high linearity at 0.99. Furthermore, the deformable mirror's influence matrix was computed, aligning with the Zernike standard surface shape of the order 1-3. To quantify aberration correction capabilities, fitting residuals for both models were calculated. The results indicate an average removal of 96.8% of aberrations to the human eye. This underscores that the optimized model outperforms the classical model in correcting high-order aberrations.

2.
Cell Death Discov ; 8(1): 315, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35821018

RESUMO

Cardiac ischemia-reperfusion (I/R) is associated with a high rate of complications. Restoring microvascular function is crucial for cardiac repair. However, the molecular mechanisms by which the circRNAs repairs microvascular dysfunction are unknown. High-throughput RNA sequencing and quantitative real-time PCR (qRT-PCR) were used to measures circRNA levels in cardiac tissue samples. We found a total of 80 up-regulated and 54 down-regulated differentially expressed circRNAs, of which mmu_circ_0000021 were consistent with bioinformatics predictions. Next, mmu_circ_0000021 knockdown and overexpression were performed to indicate the functional role of mmu_circ_0000021. The interaction of mmu_circ_0000021, miR-143-3p and NPY were evaluated using dual-luciferase assays, RNA pull-down assays and RNA immunoprecipitation (RIP). Immunohistochemistry, transmission electron microscopy, and immunofluorescence were used to determine the presence of leukocytes and changes in microvascular morphology and function. Mechanistically, mmu_circ_0000021 involved in regulating microvascular dysfunction via miR-143-3p by targeting NPY. However, the contraction of microvascular spasm caused by NPY is related to calmodulin. By regulating NPY, Circular RNA (circRNA) further affects microvascular spasm, regulates microcirculation disorders, and restores cardiac function. Our findings highlight a novel role for mmu_circ_0000021 by regulating microvascular function following I/R injury.

3.
Front Pharmacol ; 12: 598959, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679395

RESUMO

Activating transcription factor 3 (ATF3) has been confirmed to be responsive to oxidative stress and to negatively regulate the activity of Toll-like receptor 4 (TLR4). However, the effect of ATF3 on cardiac microvascular ischemia/reperfusion (I/R) injury remains unknown. The GEO2R online tool was employed to obtain differentially expressed genes GSE4105 and GSE122020, in two rat I/R injury microarray datasets. We established a rat myocardial I/R model in vivo, and also generated an in vitro hypoxia/reoxygenation (H/R) model of cardiomyoblast H9c2 cells. Overexpression of ATF3 was achieved by adenoviral-mediated gene transfer (Ad-ATF3). Rats were randomly divided into four groups: sham, I/R, I/R + Ad-Lacz (as a control), and I/R + Ad-ATF3. ELISA, CCK-8, DCFH-DA probe, qRT-PCR and Western blotting were used to determine the expression of ATF3, oxidative indices, cellular injury and TLR4/NF-κB pathway-associated proteins. Transmission electron microscopy, immunohistochemistry and immunofluorescence were used to detect the leukocyte infiltration and the alteration of microvascular morphology and function in vivo. Echocardiographic and hemodynamic data were also obtained. Bioinformatics analysis revealed that ATF3 was upregulated in I/R myocardia in two independent rat myocardial I/R models. Cardiac microvascular I/R injury included leukocyte infiltration, microvascular integrity disruption, and microvascular perfusion defect, which eventually resulted in the deterioration of hemodynamic parameters and heart function. Ad-ATF3 significantly restored microvascular function, increased cardiac microvascular perfusion, and improved hemodynamic parameters and heart function. Mechanistically, Ad-ATF3 ameliorated oxidative stress, inhibited TLR4/NF-κB pathway activation and down-regulated the expression of downstream proinflammatory cytokines in I/R myocardium in vivo and in H/R H9c2 cells in vitro. ATF3 overexpression protects against cardiac microvascular I/R injury in part by inhibiting the TLR4/NF-κB pathway and oxidative stress.

4.
Oxid Med Cell Longev ; 2021: 3763529, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33520084

RESUMO

PURPOSE: Studies have found that microRNAs (miRNAs) are closely associated with atrial fibrillation, but their specific mechanism remains unclear. The purpose of this experiment is to explore the function of miR-29b-3p in regulating atrial remodeling by targeting PDGF-B signaling pathway and thereby also explore the potential mechanisms. METHODS: We randomly divided twenty-four rats into four groups. Caudal intravenous injections of angiotensin-II (Ang-II) were administered to establish atrial fibrosis models. Expressions of miR-29b-3p and PDGF-B were then tested via RT-PCR, western blot, and immunohistochemistry. Binding sites were then analyzed via the bioinformatics online software TargetScan and verified by Luciferase Reporter. We used Masson staining to detect the degree of atrial fibrosis, while immunofluorescence and western blot were used to detect the expressions of Collagen-I and a-SMA. We used immunohistochemistry and western blot to detect the expression of connexin 43 (Cx43). RESULTS: In comparison with the Ang-II group, miR-29b-3p was seen to lower the degree of atrial fibrosis, decrease the expression of fibrosis markers such as Collagen-I and a-SMA, and increase the protein expression of Cx43. MiR-29b-3p can lower the expression of PDGF-B, while the Luciferase Reporter showed that PDGF-B is the verified target gene of miR-29b-3p. CONCLUSIONS: MiR-29b-3p was able to reduce atrial structural and electrical remodeling in the study's rat fibrosis model. This biological function may be expressed through the targeted regulation of the PDGF-B signaling pathway.


Assuntos
Remodelamento Atrial , Regulação da Expressão Gênica , MicroRNAs/biossíntese , Proteínas Proto-Oncogênicas c-sis/biossíntese , Transdução de Sinais , Animais , Masculino , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-sis/genética , Ratos , Ratos Sprague-Dawley
5.
Microcirculation ; 28(1): e12657, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32892409

RESUMO

OBJECTIVE: This study examined the correlation between serum miR-98-5p levels and indices of microvascular reperfusion in patients undergoing primary percutaneous coronary intervention (pPCI) after ST-segment elevation myocardial infarction (STEMI). Additionally, we evaluated the mechanisms by which miR-98-5p promoted ischemia/reperfusion (I/R)-induced injury in both cultured cell lines and an animal model. METHODS: Circulating miR-98-5p levels were measured and compared from 171 STEMI patients undergoing pPCI, who were divided into two groups: no-reflow and reflow. The levels of miR-98-5p, nerve growth factor (NGF), and transient receptor potential vanilloid 1 (TRPV1) were analyzed in cultured human coronary endothelial cells (HCECs) exposed to hypoxia/reoxygenation (H/R). The effects of antagomir-98-5p on myocardial I/R-induced microvascular dysfunction in vivo were evaluated. Target gene expression and activity were assessed. RESULTS: Higher miR-98-5p levels were associated with compromised indices of microvascular reperfusion. In vitro experiments on HCECs showed that exposure to H/R significantly increased miR-98-5p levels. We identified NGF as a novel target of miR-98-5p. Further, antagomir-98-5p relieved microvascular dysfunction and enhanced the expression of NGF and TRPV1 in the rat myocardial I/R model. CONCLUSIONS: MiR-98-5p promotes microvascular dysfunction by targeting the NGF-TRPV1 axis. Serum miR-98-5p serves as a potential biomarker for microvascular reperfusion.


Assuntos
Vasos Coronários/metabolismo , MicroRNAs/sangue , Microvasos/metabolismo , Traumatismo por Reperfusão Miocárdica/sangue , Fator de Crescimento Neural/sangue , Idoso , Biomarcadores/sangue , Células Cultivadas , Vasos Coronários/patologia , Células Endoteliais/metabolismo , Células Endoteliais/fisiologia , Feminino , Seguimentos , Regulação da Expressão Gênica , Humanos , Masculino , Microvasos/patologia , Pessoa de Meia-Idade , Traumatismo por Reperfusão Miocárdica/patologia
6.
Medicine (Baltimore) ; 99(34): e21860, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32846837

RESUMO

BACKGROUND: The use of fluoroquinolone antibiotics has been restricted in children because of their potential to cause adverse musculoskeletal events. This study was performed to systematically evaluate whether there is a difference between fluoroquinolone and non-fluoroquinolone antibiotics in terms of their associated risk of adverse musculoskeletal events in children. METHODS: Cochrane Library, Embase, and PubMed databases were used to retrieve studies related to fluoroquinolone and non-fluoroquinolone-induced musculoskeletal adverse events in children. A meta-analysis was performed using Stata 11. RESULTS: A total of 10 studies were included in the analysis. The combined results showed that there was no statistical difference between fluoroquinolone and non-fluoroquinolone groups in terms of musculoskeletal adverse events in children (risk ratio = 1.145, 95% confidence interval = 0.974 - 1.345, P = .101). Subgroup analysis was performed using a random-effects model. Here, the effects on the trovafloxacin and levofloxacin groups were significantly different from that of the control group. However, musculoskeletal adverse events due to either drug was not reported after long-term follow-up. CONCLUSIONS: The results showed that fluoroquinolone and non-fluoroquinolone antibiotics were not different in terms of their ability to cause musculoskeletal adverse events in children. For this reason, fluoroquinolone antibiotics can be used in children as appropriate. PROSPERO REGISTRATION NUMBER: CRD42019133900.


Assuntos
Antibacterianos/efeitos adversos , Infecções Bacterianas/tratamento farmacológico , Fluoroquinolonas/efeitos adversos , Sistema Musculoesquelético/efeitos dos fármacos , Adolescente , Antibacterianos/uso terapêutico , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Fluoroquinolonas/uso terapêutico , Humanos , Lactente , Recém-Nascido , Levofloxacino/efeitos adversos , Levofloxacino/uso terapêutico , Masculino , Naftiridinas/efeitos adversos , Naftiridinas/uso terapêutico , Estudos Retrospectivos , Sensibilidade e Especificidade , Inibidores da Topoisomerase II/efeitos adversos , Inibidores da Topoisomerase II/uso terapêutico
7.
Drug Des Devel Ther ; 14: 895-905, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32161448

RESUMO

PURPOSE: Myocardial ischemia-reperfusion injury (MIRI) is a common pathophysiological process after occlusion of the blood vessels to restore blood supply. Apoptosis is one of the ways of myocardial cell death in this process. MicroRNAs (miRNAs), a class of short and noncoding RNAs, are involved in multiple biological processes by post-transcriptionally targeting their downstream effectors. To date, whether miRNAs exert biological effects in myocardial ischemia-reperfusion (I/R) injury remains to be further studied. METHODS: In this study, we induced MIRI model by ligating rat left anterior descending artery (LAD) for 30 mins and reperfusion for 2 hrs. The differential expression profile of miRNAs in rat models of MIRI was analyzed by miRNAs sequencing. RESULTS: We found that miRNAs sequencing analysis showed the expressions of 15 types of miRNAs, including miR-346, were downregulated and 29 types of miRNAs were elevated in the MIRI rat model. We observed the key regulator of apoptosis Bax was a predicted downstream target of miR-346 using online software TargetScan. And luciferase reporter assay was utilized to certify this prediction. Over-expression of miR-346 can attenuate myocardial injury and narrow infarct area by inhibiting myocardial cell apoptosis in rat models. CONCLUSION: This study revealed a novel pathway, miR-346/Bax axis, in the regulation of apoptosis in MIRI and which might be a new molecular mechanism and therapeutic target.


Assuntos
Apoptose , MicroRNAs/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Proteína X Associada a bcl-2/antagonistas & inibidores , Animais , Masculino , MicroRNAs/genética , Traumatismo por Reperfusão Miocárdica/patologia , Ratos , Ratos Sprague-Dawley , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
8.
Oxid Med Cell Longev ; 2019: 5703764, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178968

RESUMO

MicroRNAs (miRNAs) are regarded as a potential method for the treatment of atrial fibrillation (AF) although its molecular mechanism remains unknown. We found in our previous study that the level of peripheral blood miR-27b-3p and the expression of atrial tissue CX43 were both significantly downregulated in AF patients. In the present study, we propose and test this hypothesis that overexpression of miR-27b-3p attenuates atrial fibrosis, increases CX43 expression, and regulates the signaling pathway of Wnt/ß-Catenin by targeting Wnt3a. miR-27b-3p overexpression was induced by rat tail vein injection of adeno-associated virus. Two weeks after transfection of adeno-associated virus, the rat AF model was established by tail vein injection of acetylcholine- (ACh-) CaCl2 for 7 days, and 1 ml/kg was injected daily. The incidence and duration of AF were recorded with an electrocardiogram. Cardiac function was monitored by cardiac ultrasound. Serum cardiac enzyme was detected by ELISA. The expression of atrial miR-27b-3 and Wnt3a was assayed by quantitative RT-PCR. Atrial fibrosis was determined by Masson's trichrome staining. Expression of atrial Collagen-I and Collagen-III was tested by the immunohistochemical method. Expression of CX43 was measured by immunofluorescence. The expression of Collagen-I, a-SMA, Collagen-III, TGF-ß1, CX43, Wnt3a, ß-Catenin, and p-ß-Catenin was assayed by western blot. Our results showed that miR-27b-3p overexpression could reduce the incidence and duration of AF, alleviate atrial fibrosis, increase atrial CX43 expression, and decrease the expression of Collagen-I, a-SMA, Collagen-III, TGF-ß1, Wnt3a, and p-ß-Catenin. In addition, the results of luciferase activity assay showed that Wnt3a is a validated miR-27b-3p target in HEK 293T cells. Our results provide a new evidence that miR-27b-3p regulates the signaling pathway of Wnt/ß-Catenin by targeting Wnt3a, which may play an important role in the development of atrial fibrosis and AF.


Assuntos
Fibrilação Atrial/metabolismo , MicroRNAs/metabolismo , Via de Sinalização Wnt , Proteína Wnt3A/metabolismo , beta Catenina/metabolismo , Animais , Fibrilação Atrial/genética , Fibrilação Atrial/patologia , Fibrilação Atrial/fisiopatologia , Conexina 43/biossíntese , Conexina 43/genética , Fibrose , Células HEK293 , Átrios do Coração/metabolismo , Átrios do Coração/patologia , Átrios do Coração/fisiopatologia , Humanos , Masculino , MicroRNAs/biossíntese , MicroRNAs/genética , Ratos , Ratos Sprague-Dawley , Proteína Wnt3A/genética , beta Catenina/genética
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