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1.
BMC Cardiovasc Disord ; 24(1): 129, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38424525

RESUMEN

PURPOSE: This study was aimed to identify the risk factors that influence the mortality risk in patients with acute aortic dissection (AAD) within one year after discharge, and aimed to construct a predictive model for assessing mortality risk. METHODS: The study involved 320 adult patients obtained from the Medical Information Mart for Intensive Care (MIMIC) database. Logistic regression analysis was conducted to identify potential risk factors associated with mortality in AAD patients within one year after discharge and to develop a predictive model. The performance of the predictive model was assessed using the receiver operating characteristic curve (ROC), calibration curve, and decision curve analysis (DCA). To further validate the findings, patient data from the First Affiliated Hospital of Guangxi Medical University (157 patients) were analyzed. RESULTS: Univariate and multivariate logistic regression analyses revealed that gender, length of hospital stay, highest blood urea nitrogen (BUN_max), use of adrenaline, and use of amiodarone were significant risk factors for mortality within one year after discharge (p < 0.05). The constructed model exhibited a consistency index (C-index) and an area under the ROC curve of 0.738. The calibration curve and DCA demonstrated that these indicators had a good degree of agreement and utility. The external validation results of the model also indicated good predictability (AUC = 0.700, p < 0.05). CONCLUSION: The personalized scoring prediction model constructed by gender, length of hospital stays, BUN_max levels, as well as the use of adrenaline and amiodarone, can effectively identify AAD patients with high mortality risk within one year after discharge.


Asunto(s)
Amiodarona , Disección Aórtica , Adulto , Humanos , Estudios Transversales , Alta del Paciente , China/epidemiología , Disección Aórtica/diagnóstico , Disección Aórtica/terapia , Epinefrina , Factores de Riesgo , Estudios Retrospectivos
2.
Heart Surg Forum ; 25(2): E243-E252, 2022 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-35486057

RESUMEN

Cardiopulmonary bypass (CPB), though indispensable in many cardiac surgery procedures, has several undesirable consequences. The aim of this study was to identify potential genes that may reduce the inflammatory response and complications after CPB. The GSE132176 dataset was selected from the Gene Expression Omnibus (GEO) database and included 10 patients with tetralogy of Fallot and 10 patients with an atrial septal defect who underwent CPB surgery. TSV files were downloaded after GEO2R processing. Protein-protein interaction analysis of common differentially expressed genes (DEGs) was performed using the Search Tool for the Retrieval of Interacting Genes. Gene modules and hub genes were visualized in the protein-protein interaction network using Cytoscape. Enrichment analysis was performed for all important DEGs, modular genes, and hub genes. A total of 72 DEGs were screened, including two functional and one hub gene module. FOS modular genes were primarily enriched in NGF-stimulated transcription, spinal cord injury, and PID AP1 pathway. The ATF3 modular gene was mainly enriched in cytomegalovirus infection and transcriptional misregulation in cancer. Hub gene modules were primarily enriched in the PID AP1 pathway, positive regulation of pri-miRNA transcription by RNA polymerase II, and the PID ATF2 pathway. FOS, JUN, ATF3, and EGR1 were the four most important hub genes; the top three hub genes were involved in the formation of AP-1 and enriched in the AP-1 pathway. Finally, we measured the expression levels of these four genes in patients undergoing CPB via qRT-PCR, and the results were consistent with those obtained in bioinformatic analysis. FOS, JUN, ATF3, and EGR1 and the AP-1 pathway may play key roles in inflammation and complications caused by CPB.


Asunto(s)
Biología Computacional , Perfilación de la Expresión Génica , Puente Cardiopulmonar/efectos adversos , Biología Computacional/métodos , Perfilación de la Expresión Génica/métodos , Humanos , Inflamación/genética , Inflamación/prevención & control , Factor de Transcripción AP-1
3.
J Thorac Dis ; 14(12): 4803-4814, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36647496

RESUMEN

Background: Left ventricular ejection fraction (LVEF) is an indicator of heart failure, and it is controversial whether patients with reduced preoperative left ventricular ejection fraction can benefit from heart valve surgery. We aimed to assess the differences in clinical characteristics after surgery in patients with different grades of reduced preoperative LVEF to guide clinical management. Methods: A total of 100 heart valve disease patients with low LVEF (≤50%) who had undergone valve surgery in the Department of Cardiology. The patients were divided into three groups according to their LVEF measured by echocardiography before surgery, with LVEF ≤40% as group A, 40%< LVEF ≤45% as group B, and 45%< LVEF ≤50% as group C. Clinical characteristics such as postoperative LVEF values, oxygenation index, liver function and inflammatory index, intra-aortic balloon pump (IABP) utilization rate, and mortality were compared among the three groups of patients. Results: There was no statistically significant difference in the preoperative baseline data between the three groups of patients (P>0.05). The clinical outcomes of patients in group A (n=28) were similar to those of patients in groups B (n=39) and C (n=33) (P>0.05). The vasoactive-inotropic score (VIS), postoperative ventilator use time, length of stay in the care unit, IABP use rate, and mortality rate on the first postoperative day were higher in group A. By comparing the preoperative and postoperative (within 48 hours and 3 months after surgery) cardiac echocardiograms of the three groups, we learned that LVEF increased, LV end-systolic internal diameter and LV end-diastolic internal diameter decreased, and ventricular remodeling improved after surgery compared with the preoperative period (P<0.05). The postoperative improvement was more obvious in group A than in groups B and C. Three months after surgery, LVEF increased to 55%, the LV end-systolic internal diameter decreased to 39 mm, and the LV end-diastolic internal diameter decreased to about 55 mm in each group (P>0.05). Conclusions: Patients with heart valve disease and low LVEF should be actively treated with heart valve surgery, which can significantly improve the patient's left ventricular reverse remodeling and cardiac function, thereby facilitating survival.

4.
Sci Rep ; 11(1): 17229, 2021 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-34446752

RESUMEN

To develop and design mg-based nanoalloys with excellent properties, it is necessary to explore the forming process. In this paper, to explore the effect of different loading directions on the phase transformation of magnesium alloy, the model of AZ31 magnesium alloy was established, the process of Uniaxial Compression (UC) of magnesium alloy in different directions was simulated, the changes of atomic position and phase structure were observed, and the phase transformation mechanism of AZ31 magnesium alloy under uniaxial compression under different loading directions was summarized. The conclusions are as follows: the stress and strain, potential energy and volume change, void evolution, phase structure change and dislocation evolution of magnesium alloy are consistent, and there is no significant difference. In the process of uniaxial compression, the phase transformation of hexagonal closely packed (HCP) → face-centered cubic (FCC) is the main, and its structure evolves into HCP → Other → FCC. Shockley partial dislocations always precede FCC stacking faults by about 4.5%, and Shockley partial dislocations surround FCC stacking faults. In this paper, the phase transformation mechanism of AZ31 magnesium alloy under uniaxial compression under different loading directions is summarized, which provides a theoretical basis for the processing and development of magnesium-based nanoalloys.

5.
J Mol Cell Cardiol ; 159: 80-90, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34097926

RESUMEN

Circular RNAs (circRNAs) are essential regulators associated with many cardiac conditions, including myocardial infarction (MI). This study aimed to explore circRNA expression during MI development in an animal model and in hypoxia/reoxygenation (H/R)-treated cardiomyocytes. Microarray and real-time quantitative PCR showed that the circRNA PVT1 (circPVT1) was expressed at high levels in MI tissues and H/R-triggered cardiomyocytes. Loss-of-function assays were utilized for examining the influence of circPVT1 on cardiac function and cardiomyocyte properties. Cardiac function was measured by echocardiography at 7 d after MI. Reduced circPVT1 expression significantly decreased MI-triggered myocardial infarct size by 60% and prevented MI-triggered reductions in fractional shortening (%FS) and ejection fraction (EF%). Results of LDH, CCK-8, EdU staining, colony formation assays, and flow cytometry showed that circPVT1 silencing restored cell viability and proliferation while decreased apoptosis. Mechanistic experiments indicated that microRNAs (miR)-125b and miR-200a associated with circPVT1. We demonstrated that circPVT1 functioned as a competitive endogenous RNA (ceRNA) to sponge both miR-125b and miR-200a. Gain-of-function assays showed that miR-125b and miR-200a upregulation partially eliminated the effects of circPVT1 on cardiomyocyte properties. In addition, we found that the previously reported p53/TRAF6, SIRT7, Keap1/Nrf2, and PDCD4 pathways were regulated by the circPVT1/miR-125b/miR-200a axis. In conclusion, our study suggests that circPVT1 protects the myocardium from MI and H/R injury by preventing miR-125b- and miR-200a-mediated apoptotic signaling.


Asunto(s)
MicroARNs/genética , Interferencia de ARN/fisiología , ARN Circular/genética , ARN Largo no Codificante/genética , Daño por Reperfusión/genética , Animales , Apoptosis/genética , Proliferación Celular/genética , Supervivencia Celular/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Ratas , Transducción de Señal/genética , Regulación hacia Arriba/genética
6.
Materials (Basel) ; 14(10)2021 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-34064781

RESUMEN

The hot deformation behavior of a newly designed Fe-5Mn-3Al-0.1C (wt.%) medium manganese steel was investigated using hot compression tests in the temperature range of 900 to 1150 °C, at constant strain rates of 0.1, 1, 2.5, 5, 10, and 20 s-1. A detailed analysis of the hot deformation parameters, focusing on the flow behavior, hot processing map, dynamic recrystallization (DRX) critical stress, and nucleation mechanism, was undertaken to understand the hot rolling process of the newly designed steel. The flow behavior is sensitive to deformation parameters, and the Zener-Hollomon parameter was coupled with the temperature and strain rate. Three-dimensional processing maps were developed considering the effect of strain and were used to determine safe and unsafe deformation conditions in association with the microstructural evolution. In the deformation condition, the microstructure of the steel consisted of δ-ferrite and austenite; in addition, there was a formation of DRX grains within the δ-ferrite grains and austenite grains during the hot compression test. The microstructure evolution and two types of DRX nucleation mechanisms were identified; it was observed that discontinuous dynamic recrystallization (DDRX) is the primary nucleation mechanism of austenite, while continuous dynamic recrystallization (CDRX) is the primary nucleation mechanism of δ-ferrite. The steel possesses unfavorable toughness at the deformation temperature of 900 °C, which is mainly due to the presence of coarse κ-carbides along grain boundaries, as well as the lower strengthening effect of grain boundaries. This study identified a relatively ideal hot processing region for the steel. Further exploration of hot roll tests will follow in the future.

7.
J Vis Exp ; (163)2020 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-33016945

RESUMEN

In this work, an easy, low-cost, and widely applicable method was developed to improve the compatibility between the ceramic fillers and the polymer matrix by adding 3-aminopropyltriethoxysilane (KH550) as a coupling agent during the fabrication process of BaTiO3-P(VDF-CTFE) nanocomposites through solution casting. Results show that the use of KH550 can modify the surface of ceramic nanofillers; therefore, good wettability on the ceramic-polymer interface was achieved, and the enhanced energy storage performances were obtained by a suitable amount of the coupling agent. This method can be used to prepare flexible composites, which is highly desirable for the production of high-performance film capacitors. If an excessive amount of coupling agent is used in the process, the non-attached coupling agent can participate in complex reactions, which leads to a decrease in dielectric constant and an increase in dielectric loss.


Asunto(s)
Electricidad , Nanocompuestos/química , Polímeros/química , Compuestos de Bario , Nanocompuestos/ultraestructura , Propiedades de Superficie , Titanio
8.
Med Sci Monit ; 26: e918933, 2020 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-32048631

RESUMEN

BACKGROUND Interleukin-36 has been demonstrated to be involved in inflammatory responses. Inflammatory responses due to ischemia-reperfusion injury following cardiopulmonary bypass (CPB) can cause heart dysfunction or damage. MATERIAL AND METHODS The CPB models were constructed in IL-36R-/-, IL-36RN-/-, and wild-type SD rats. Ultrasonic cardiography and ELISA were used to evaluate the cardiac function and measuring myocardial biomarker levels in different groups. TUNEL assay was used to evaluate apoptosis. Western blot assays and RT-PCR were performed to measure the expression of chemokines and secondary inflammatory cytokines in the heart. Oxidative stress in tissue and cultured cells was assessed using a DCFH-DA fluorescence probe and quantification of superoxide dismutase activity. RESULTS Improved systolic function and decreased serum levels of myocardial damage biomarkers were found in IL-36R-/- rats compared to WT rats, while worse cardiac function and cardiomyocyte IR injury were observed in IL-36RN-/- rats compared to WT rats. TUNEL staining and Western blot analyses found that cardiomyocyte apoptosis and inflammation were significantly lower in the hearts of IL-36R-/- rats compared with that of WT rats. Oxidative stress was significantly lower in IL-36R-/- rats compared to WT rats. iNOS expression was significantly reduced, while eNOS expression was increased in the hearts of IL-36R-/- rats. Silencing of IL-36R expression in vitro activated SIRT1/FOXO1/p53 signaling in cardiomyocytes. CONCLUSIONS IL-36R deficiency in cardiomyocytes repressed infiltration of bone marrow-derived inflammatory cells and oxidative stress dependent on SIRT1-FOXO1 signaling, thus protecting cardiomyocytes and improving cardiac function in CPB model rats.


Asunto(s)
Puente Cardiopulmonar/efectos adversos , Daño por Reperfusión Miocárdica/inmunología , Miocardio/patología , Miocitos Cardíacos/patología , Receptores de Interleucina/deficiencia , Animales , Modelos Animales de Enfermedad , Técnicas de Inactivación de Genes , Humanos , Masculino , Daño por Reperfusión Miocárdica/patología , Miocardio/citología , Miocardio/inmunología , Miocitos Cardíacos/inmunología , Proteínas del Tejido Nervioso/metabolismo , Estrés Oxidativo/genética , Estrés Oxidativo/inmunología , Ratas , Ratas Transgénicas , Receptores de Interleucina/genética , Receptores de Interleucina/metabolismo , Transducción de Señal/genética , Transducción de Señal/inmunología , Sirtuina 1/metabolismo
9.
Materials (Basel) ; 12(23)2019 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-31771135

RESUMEN

A new rolling process of the 304/Q345R composite plate based on a corrugated interface was developed. Through numerical simulation and rolling experiments, the metal deformation law, the stress and strain field distribution, and the bond strength of the corrugated plate were studied. By comparison, the corrugated interface effectively increased the length of the composite interface. Also, the composite interface from the 2D corrugated surface became a 3D corrugated surface, and a combination of the 304/Q345R composite plate metallurgy was achieved with a low reduction rate. Simultaneously, the interface bonding strength was improved.

10.
Materials (Basel) ; 12(10)2019 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-31130678

RESUMEN

Low chromium ferritic stainless steel has great potential in automobile structures for improved strength. In this study, quenching and partitioning (Q-P) treatment was applied to a low-carbon-chromium ferritic stainless steel and compared with traditional heat treatment (quenching-tempering [Q-T] and annealing) in terms of microstructure, mechanical properties, corrosion resistance, and deformation of plate. The results show that the quenching and partitioning (Q-P) treatment has a series of advantages over conventional heat treatments (quenching-tempering and annealing). In terms of mechanical properties, it achieves a good match between strength and plasticity by combining the advantages of "soft state" with high elongation resulting from conventional annealing and high strength "hard state" through the traditional quenching-tempering process. The material possesses better crash safety; for the quenching-partitioning (Q-P) process, quenching-tempering process, and annealing process, the production of strength plasticity is about 16 GPa%, 15 GPa%, and 14 GPa%, respectively. The material has low yield strength, high work hardening index (compared with Q-T), a smooth tensile curve, and no yield plateau (compared with annealing), so it has better forming performance and processing surface, and the corrosion resistance has also improved. The pitting potential of the samples produced by the quenching treatment of Q-P and Q-T increased by about 0.2 V, which is about 20% higher than the one by the traditional annealing process.

11.
Sci Rep ; 7: 46729, 2017 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-28466846

RESUMEN

This study is to quantitatively evaluate the efficacy of using a non-contact automatic articulating paper dispenser for reducing microbial articulating paper contamination. Articulating papers in four-handed mode, non-four-handed mode, and via an automatic articulating paper dispenser were evaluated. An adenosine triphosphate bioluminescence assay was used to quantitatively measure the relative light unit (RLU) values of the rest unused articulating papers in the same package to detect contamination at 4 time points, and triplicate examinations were performed for all three methods. The RLUs were recorded, compared, and evaluated. For four-handed mode (n = 36), the RLUs at the four time points were 2.44, 32.89, 37.89, and 27.22, with a satisfactory rate of 94%. The RLUs for non-four-handed mode (n = 36) were 2.22, 286.44, 299.44, and 493.56, with a satisfactory rate of 36%. The RLUs for using the automatic dispenser (n = 36) were all 0 with a satisfactory rate of 100%. The satisfactory rates were significantly different among three methods. No significant differences were observed in the satisfactory rates for the four time points samples. Contact by gloved hands can cause severe biological contamination of articulating paper. However, by using standard four-handed mode or a non-contact automatic articulating paper dispenser, contamination can be controlled.


Asunto(s)
Adenosina Trifosfato/metabolismo , Equipo Dental/microbiología , Contaminación de Equipos/prevención & control , Diseño de Equipo/métodos , Mediciones Luminiscentes/métodos , Recuento de Colonia Microbiana , Humanos , Control de Infecciones/métodos , Reproducibilidad de los Resultados
12.
Biosens Bioelectron ; 26(4): 1313-9, 2010 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-20688505

RESUMEN

Current bacterial detection methods require the collection of samples followed by preparation and analysis in the laboratory, both time and labour consuming steps. More importantly, because of cost, only a limited number of samples can be taken and analyzed. This paper presents the results of an investigation to directly detect Salmonella typhimurium on fresh tomato surfaces using phage-based magnetoelastic (ME) biosensors. The biosensor is composed of a ME resonator platform coated with filamentous E2 phage, engineered to bind with S. typhimurium. The ME biosensors are wireless sensors, whose resonance oscillation and resonance frequency are actuated and detected through magnetic fields. The sensors used in this study were 0.028 mm×0.2 mm×1 mm in size. In this study, the tomato surface was spiked with S. typhimurium suspensions with concentrations ranging from 5×10(1) to 5×10(8)CFU/ml and then allowed to dry in air. The detection was conducted by directly placing ME measurement biosensors and control sensors on the spiked surface for 30 min in a humid environment. The control sensors were identical to the measurement biosensors, but without phage. Both measurement and control sensors were blocked with BSA to reduce non-specific binding. The resonance frequencies of both measurement and control sensors were measured prior to and after the placement of the sensors on the tomato. Shifts in the resonance frequency of the measurement biosensors were observed, while the control sensors showed negligible change. Scanning electron microscopy (SEM) was used to verify the specific binding of S. typhimurium to the biosensor. Results of multiple biosensor detection and corresponding analyzes showed statistically different responses between the measurement and control sensors for tomatoes spiked with S. typhimurium suspensions with concentrations of 5×10(2)CFU/ml and greater. This study demonstrates the direct detection of food-borne bacteria on fresh produce.


Asunto(s)
Técnicas Biosensibles/métodos , Microbiología de Alimentos/métodos , Salmonella typhimurium/aislamiento & purificación , Carga Bacteriana/métodos , Elasticidad , Humanos , Solanum lycopersicum/microbiología , Solanum lycopersicum/ultraestructura , Magnetismo , Microscopía Electrónica de Rastreo , Intoxicación Alimentaria por Salmonella/prevención & control , Fagos de Salmonella , Salmonella typhimurium/patogenicidad , Salmonella typhimurium/ultraestructura , Salmonella typhimurium/virología , Propiedades de Superficie
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