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1.
IUBMB Life ; 76(9): 731-744, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38651683

RESUMEN

Long noncoding RNAs (LncRNAs) play essential roles in regulating gene expression in various biological processes. However, the function of lncRNAs in vascular smooth muscle cell (VSMC) transformation remains to be explained. In this work, we discover that a new bone marrow protein (BMP) signaling target, lncRNA RP11-301G19.1, is significantly induced in BMP7-treated VSMCs through lncRNA microarray analysis. Addition of BMP signaling inhibitor LDN-193189 attenuates the expression of ACTA2 and SM-22α, as well as the mRNA level of RP11-301G19.1. Furthermore, lncRNA RP11-301G19.1 is critical to the VSMC differentiation and is directly activated by SMAD1/9. Mechanistically, knocking down of RP11-301G19.1 leads to the decrease of ATOH8, another BMP target, while the forced expression of RP11-301G19.1 reactivates ATOH8. In addition, miR-17-5p, a miRNA negatively regulated by BMP-7, contains predicted binding sites for lncRNA RP11-301G19.1 and ATOH8 3'UTR. Accordingly, overexpression of miR-17-5p decreases the levels of them. Together, our results revealed the role of lncRNA RP11-301G19.1 as a miRNA sponge to upregulate ATOH8 in VSMC phenotype transformation.


Asunto(s)
MicroARNs , Músculo Liso Vascular , Miocitos del Músculo Liso , ARN Largo no Codificante , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/citología , Humanos , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/efectos de los fármacos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Regulación de la Expresión Génica , Transducción de Señal , Fenotipo , Diferenciación Celular , Células Cultivadas , Animales , Proteína Morfogenética Ósea 7/genética , Proteína Morfogenética Ósea 7/metabolismo , Contracción Muscular/efectos de los fármacos
2.
Phys Chem Chem Phys ; 25(32): 21649-21660, 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37551529

RESUMEN

Diamond tools play a vital role in precision machining. However, the adhesive wear restricts their application when Fe-based workpieces are cut by diamond tools. Thus, it is significant to theoretically explain the interface binding mechanism between the diamond and Fe alloy matrix. In this study, the adhesion and friction behaviors of a γ-Fe/diamond (denoted as Fe/C) heterogeneous contact interface were investigated employing density functional theory (DFT). The results show that the transfer of the Fe atom to C atom occurs when the interaction energy for a given configuration is larger than the separation energy of the corresponding Fe surface layers. The energy barriers of the Fe/C(100), (110) and (111) sliding interfaces along the minimum energy path are 1.45, 0.48 and 0.42 J m-2, respectively, indicating that the Fe/C(111) interface is the easiest to slide. Furthermore, the friction potential barrier increases with an increase in the load (1-5 nN) according to the potential energy curves. Moreover, the friction coefficient of the Fe/C interface is larger than 0.2 and provides a theoretical minimum friction coefficient for the Fe/C sliding interface.

3.
Phys Chem Chem Phys ; 24(8): 5171-5184, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35166285

RESUMEN

A tetragonal C4N (t-C4N) structure was predicted via CALYPSO code, and the effects of pressure on its structural and mechanical properties were studied. The results show that t-C4N is different from various 2D CxNy compounds with a new type 3D crystal structure, which is similar to diamond. Bulk t-C4N is equipped with excellent elastic properties. When the pressure is increased from 0 GPa to 350 GPa, its bulk modulus B, shear modulus G and Young's modulus E are increased from 426.9 GPa to 1123.1 GPa, 371.4 GPa to 582.9 GPa and 863.7 GPa to 1490.9 GPa, respectively. The anisotropic Bmax, Gmax and Emax are increased from 582.38 GPa to 1751.41 GPa, 478.29 GPa to 1033.97 GPa and 1281.26 GPa to 2490.14 GPa, respectively. When the pressure is 0 GPa, the hardness calculated by Chen's and Tian's models are 51.15 GPa and 51.81 GPa, respectively. Its ideal tensile strength in [111] orientation is the smallest (63.46 GPa), which indicates that the (111) planes allow easy cleavage. The smallest ideal shear strength (67.98 GPa) can be obtained in the (111)[11̄0] orientation, which suggests its theoretical hardness is about 67.98 GPa. Due to its excellent mechanical properties, t-C4N can be used as an industrial superhard material.

4.
Plant Cell Rep ; 41(12): 2379-2391, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36208306

RESUMEN

KEY MESSAGE: Within a QTL, the genetic recombination and interactions among five and two functional variations at MdbHLH25 and MdWDR5A caused much complicated phenotype segregation in apple FFR and FCR. The storability of climacteric fruit like apple is a quantitative trait. We previously identified 62 quantitative trait loci (QTLs) associating flesh firmness retainability (FFR) and flesh crispness retainability (FCR), but only a few functional genetic variations were identified and validated. The genetic variation network controlling fruit storability is far to be understood and diagnostic markers are needed for molecular breeding. We previously identified overlapped QTLs F16.1/H16.2 for FFR and FCR using an F1 population derived from 'Zisai Pearl' × 'Red Fuji'. In this study, five and two single-nucleotide polymorphisms (SNPs) were identified on the candidate genes MdbHLH25 and MdWDR5A within the QTL region. The SNP1 A allele at MdbHLH25 promoter reduced the expression and SNP2 T allele and/or SNP4/5 GT alleles at the exons attenuated the function of MdbHLH25 by downregulating the expression of the target genes MdACS1, which in turn led to a reduction in ethylene production and maintenance of higher flesh crispness. The SNPs did not alter the protein-protein interaction between MdbHLH25 and MdWDR5A. The joint effect of SNP genotype combinations by the SNPs on MdbHLH25 (SNP1, SNP2, and SNP4) and MdWDR5A (SNPi and SNPii) led to a much broad spectrum of phenotypic segregation in FFR and FCR. Together, the dissection of these genetic variations contributes to understanding the complicated effects of a QTL and provides good potential for marker development in molecular breeding.


Asunto(s)
Malus , Sitios de Carácter Cuantitativo , Sitios de Carácter Cuantitativo/genética , Malus/genética , Mapeo Cromosómico , Fenotipo , Polimorfismo de Nucleótido Simple/genética
5.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(1): 33-40, 2022 Jan 15.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-35177173

RESUMEN

OBJECTIVES: To investigate the clinical treatment outcomes and the changes of the outcomes over time in extremely preterm twins in Guangdong Province, China. METHODS: A retrospective analysis was performed for 269 pairs of extremely preterm twins with a gestational age of <28 weeks who were admitted to the department of neonatology in 26 grade A tertiary hospitals in Guangdong Province from January 2008 to December 2017. According to the admission time, they were divided into two groups: 2008-2012 and 2013-2017. Besides, each pair of twins was divided into the heavier infant and the lighter infant subgroups according to birth weight. The perinatal data of mothers and hospitalization data of neonates were collected. The survival rate of twins and the incidence rate of complications were compared between the 2008-2012 and 2013-2017 groups. RESULTS: Compared with the 2008-2012 group, the 2013-2017 group (both the heavier infant and lighter infant subgroups) had lower incidence rates of severe asphyxia and smaller head circumference at birth (P<0.05). The mortality rates of both of the twins, the heavier infant of the twins, and the lighter infant of the twins were lower in the 2013-2017 group compared with the 2008-2012 group (P<0.05). Compared with the 2008-2012 group, the 2013-2017 group (both the heavier infant and lighter infant subgroups) had lower incidence rates of pulmonary hemorrhage, patent ductus arteriosus (PDA), periventricular-intraventricular hemorrhage (P-IVH), and neonatal respiratory distress syndrome (NRDS) and a higher incidence rate of bronchopulmonary dysplasia (P<0.05). CONCLUSIONS: There is a significant increase in the survival rate over time in extremely preterm twins with a gestational age of <28 weeks in the 26 grade A tertiary hospitals in Guangdong Province. The incidences of severe asphyxia, pulmonary hemorrhage, PDA, P-IVH, and NRDS decrease in both the heavier and lighter infants of the twins, but the incidence of bronchopulmonary dysplasia increases. With the improvement of diagnosis and treatment, the multidisciplinary collaboration between different fields of fetal medicine including prenatal diagnosis, obstetrics, and neonatology is needed in the future to jointly develop management strategies for twin pregnancy.


Asunto(s)
Displasia Broncopulmonar , Síndrome de Dificultad Respiratoria del Recién Nacido , Displasia Broncopulmonar/epidemiología , Femenino , Edad Gestacional , Humanos , Lactante , Recien Nacido Extremadamente Prematuro , Recién Nacido , Embarazo , Síndrome de Dificultad Respiratoria del Recién Nacido/epidemiología , Estudios Retrospectivos , Resultado del Tratamiento
6.
Herz ; 46(Suppl 1): 109-114, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32123932

RESUMEN

BACKGROUND: Our study aimed to explore the incidence and risk factors of permanent pacemaker implantation (PPI) after valve replacement surgery (VR). The influence of long-term pacemaker dependency on cardiac structure and function at the 1­year follow-up was also assessed. METHODS: The demographic and surgical data of all consecutive patients who underwent VR between 2013 and 2016 were collected. Univariate and multivariate analyses were performed to identify variables independently associated with PPI after VR. A 1­year follow-up was undertaken of patients who underwent dual-chambers pacemaker after VR because of complete atrioventricular block (AVB). Long-term pacemaker dependency and recovery of cardiac structure and function were evaluated. RESULTS: There were 5320 consecutive patients with VR. The incidence of postoperative PPI was 2.42%. Multivariate analysis indicated that among the 62 patients who underwent PPI due to AVB and sick sinus syndrome, isolated aortic valve replacement (AVR; OR: 2.24, p < 0.05), VR combined with ventricular septal defect (VSD) repair (OR: 6.78, p < 0.05), and VR with aortic root and arch surgery (OR: 4.14, p < 0.05) were independent predictors of PPI after surgery. In total, 89.6% (43/48) of the survivors showed pacemaker dependency. Of these 43 patients, 24 had enlarged left heart before VR. Compared with preoperative values, the left atrial and left ventricular end-diastolic diameter post-PPI decreased significantly, while left ventricular ejection fraction was not significantly different. CONCLUSION: Isolated AVR, VR concomitant with VSD repair, and VR with aortic root and arch surgery are independent predictors of PPI after VR. The majority of patients do not recover from AVB disorders and there is no significant negative effect on recovery of cardiac structure and function.


Asunto(s)
Estenosis de la Válvula Aórtica , Prótesis Valvulares Cardíacas , Marcapaso Artificial , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Estimulación Cardíaca Artificial , Estudios de Seguimiento , Humanos , Incidencia , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
7.
J Cardiovasc Electrophysiol ; 30(11): 2414-2419, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31502295

RESUMEN

BACKGROUND: Ablation index (AI) has been evaluated as guidance quality marker for pulmonary vein isolation, but not for linear ablation of the cavotricuspid isthmus (CTI) for typical right atrial flutter (AFL). We thus studied the feasibility and effectiveness of AI-guided CTI for AFL. METHODS: Procedural and 6-month outcomes of ablation for AFL were retrospectively compared between consecutive patients undergoing either AI-guided ablation of CTI (n = 43; AI target of 500 for anterior 2/3 segments and 400 for posterior 1/3 segments) or contact force (CF)-guided ablation (n = 42) at a single center. Each Visitag dataset from all patients in each group was analyzed. RESULTS: AI guidance vs CF guidance was associated with: higher first-pass conduction block of CTI (93.0% vs 76.2%, P = .03) with similar ablation time; similar acute spontaneous CTI reconnection 2.3% vs 9.5%, P = .343); fewer radiofrequency (RF) applications (10.1 ± 2.8 vs 11.5 ± 3.0, P = .031) needed to achieve CTI directional block; significantly higher mean ablation time, impedance drop, force time integral and AI and similar mean CF and power of each VisiTag point. One inguinal hematoma and one pseudoaneurysm developed in the AI and CF groups, respectively. Recurrent AFL was recorded in two (4.7%) AI-group patients and four (9.5%) CF-group patients (P = .650). CONCLUSION: AI-guided ablation of CTI line for AFL appears feasible and effective with similar ablation time, fewer RF applications, a higher rate of first-pass conduction block, and no additional complications.


Asunto(s)
Aleteo Atrial/cirugía , Ablación por Catéter , Válvula Tricúspide/cirugía , Vena Cava Inferior/cirugía , Potenciales de Acción , Anciano , Aleteo Atrial/diagnóstico , Aleteo Atrial/fisiopatología , Ablación por Catéter/efectos adversos , Estudios de Factibilidad , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Válvula Tricúspide/fisiopatología , Vena Cava Inferior/fisiopatología
8.
BMC Pediatr ; 19(1): 405, 2019 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-31685004

RESUMEN

BACKGROUND: An increasing number of extremely preterm (EP) infants have survived worldwide. However, few data have been reported from China. This study was designed to investigate the short-term outcomes of EP infants at discharge in Guangdong province. METHODS: A total of 2051 EP infants discharged from 26 neonatal intensive care units during 2008-2017 were enrolled. The data from 2008 to 2012 were collected retrospectively, and from 2013 to 2017 were collected prospectively. Their hospitalization records were reviewed. RESULTS: During 2008-2017, the mean gestational age (GA) was 26.68 ± 1.00 weeks and the mean birth weight (BW) was 935 ± 179 g. The overall survival rate at discharge was 52.5%. There were 321 infants (15.7%) died despite active treatment, and 654 infants (31.9%) died after medical care withdrawal. The survival rates increased with advancing GA and BW (p < 0.001). The annual survival rate improved from 36.2% in 2008 to 59.3% in 2017 (p < 0.001). EP infants discharged from hospitals in Guangzhou and Shenzhen cities had a higher survival rate than in others (p < 0.001). The survival rate of EP infants discharged from general hospitals was lower than in specialist hospitals (p < 0.001). The major complications were neonatal respiratory distress syndrome, 88.0% (1804 of 2051), bronchopulmonary dysplasia, 32.3% (374 of 1158), retinopathy of prematurity (any grade), 45.1% (504 of 1117), necrotizing enterocolitis (any stage), 10.1% (160 of 1588), intraventricular hemorrhages (any grade), 37.4% (535 of 1431), and blood culture-positive nosocomial sepsis, 15.7% (250 of 1588). The multivariate logistic regression analysis indicated that improved survival of EP infants was associated with discharged from specialist hospitals, hospitals located in high-level economic development region, increasing gestational age, increasing birth weight, antenatal steroids use and a history of premature rupture of membranes. However, twins or multiple births, Apgar ≤7 at 5 min, cervical incompetence, and decision to withdraw care were associated with decreased survival. CONCLUSIONS: Our study revealed the short-term outcomes of EP infants at discharge in China. The overall survival rate was lower than the developed countries, and medical care withdrawal was a serious problem. Nonetheless, improvements in care and outcomes have been made annually.


Asunto(s)
Mortalidad Infantil , Recien Nacido Extremadamente Prematuro , Alta del Paciente/estadística & datos numéricos , Peso al Nacer , Displasia Broncopulmonar/epidemiología , Hemorragia Cerebral Intraventricular/epidemiología , China/epidemiología , Enterocolitis Necrotizante/epidemiología , Femenino , Edad Gestacional , Humanos , Lactante , Recién Nacido , Masculino , Estudios Prospectivos , Análisis de Regresión , Síndrome de Dificultad Respiratoria del Recién Nacido/epidemiología , Retinopatía de la Prematuridad/epidemiología , Estudios Retrospectivos , Tasa de Supervivencia
9.
Entropy (Basel) ; 21(4)2019 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-33267145

RESUMEN

High-entropy alloy (HEA) offers great flexibility in materials design with 3-5 principal elements and a range of unique advantages such as good microstructure stability, mechanical strength over a broad range of temperatures and corrosion resistance, etc. Welding of high entropy alloy, as a key joining method, is an important emerging area with significant potential impact to future application-oriented research and technological developments in HEAs. The selection of feasible welding processes with optimized parameters is essential to enhance the applications of HEAs. However, the structure of the welded joints varies with material systems, welding methods and parameters. A systemic understanding of the structures and properties of the weldment is directly relevant to the application of HEAs as well as managing the effect of welding on situations such as corrosion that are known to be a service life limiting factor of welded structures in conditions such as marine environments. In this paper, key recent work on welding of HEAs is reviewed in detail focusing on the research of main HEA systems when applying different welding techniques. The experimental details including sample preparation, sample size (thickness) and welding conditions reflecting energy input are summarized and key issues are highlighted. The microstructures and properties of different welding zones, in particular the fusion zone (FZ) and the heat affected zones (HAZ), formed with different welding methods are compared and presented in details and the structure-property relationships are discussed. The work shows that the weldability of HEAs varies with the HEA composition groups and the welding method employed. Arc and laser welding of AlCoCrFeNi HEAs results in lower hardness in the FZ and HAZ and reduced overall strength. Friction stir welding results in higher hardness in the FZ and achieves comparable/higher strength of the welded joints in tensile tests. The welded HEAs are capable of maintaining a reasonable proportion of the ductility. The key structure changes including element distribution, the volume fraction of face centered cubic (FCC) and body centered cubic (BCC) phase as well as reported changes in the lattice constants are summarized and analyzed. Detailed mechanisms governing the mechanical properties including the grain size-property/hardness relationship in the form of Hall-Petch (H-P) effect for both bulk and welded structure of HEAs are compared. Finally, future challenges and main areas to research are highlighted.

10.
J Cardiovasc Electrophysiol ; 29(4): 591-599, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29446182

RESUMEN

BACKGROUND: There is a close anatomical relationship between aortic sinus cusp (ASC) and the left pulmonary sinus cusp (LPSC). PURPOSE: The study was to investigate the significance of mapping and ablation of LPSC for ventricular arrhythmias (VAs) with QRS morphology resembling that of ASC arrhythmias. METHODS: In 33 consecutive patients undergoing successful catheter ablation of idiopathic VAs with ASC arrhythmia-like QRS morphology, LPSC was mapped carefully. RESULTS: Among the 33 patients studied, QRS morphology resembled that of arrhythmias of either right or left coronary cusp (LCC or RCC) origin in 17 and 16 patients, respectively. Out of 12 arrhythmias with the earliest potential in LCC during left-sided mapping, an earlier potential in LPSC than in LCC was recorded in 2 arrhythmias, the same earliest potential in LPSC as in LCC was recorded in 6 arrhythmias, and 5 (42%) were finally ablated successfully in LPSC using the reversed U curve. Out of 16 arrhythmias with the earliest potential in the RCC during left-sided mapping, an earlier potential in LPSC than in RCC was recorded in 4 arrhythmias, the same earliest potential in LPSC as in RCC was recorded in 3 arrhythmias, and 4 (25%) were finally ablated successfully in LPSC using the reversed U curve. CONCLUSIONS: For VAs with ASC arrhythmia-like QRS morphology, mapping in LPSC could have unique electrophysiologic characteristics, and some of them could be eliminated in LPSC using reversed U curve.


Asunto(s)
Potenciales de Acción , Arritmias Cardíacas/cirugía , Ablación por Catéter , Técnicas Electrofisiológicas Cardíacas , Ventrículos Cardíacos/cirugía , Venas Pulmonares/fisiopatología , Adulto , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatología , Electrocardiografía , Femenino , Frecuencia Cardíaca , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Seno Aórtico/fisiopatología , Resultado del Tratamiento
11.
Biochem Biophys Res Commun ; 477(4): 761-767, 2016 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-27363341

RESUMEN

Apoptotic and necrotic macrophages have long been known for their existence in atherosclerotic lesions. However, the mechanisms underlying the choice of their death pattern have not been fully elucidated. Here, we report the effects of PS-341, a potent and specific proteasome inhibitor, on the cell death of primary bone marrow-derived macrophages (BMDMs) in vitro. The results showed that PS-341 could not induce macrophage apoptosis or promote TNF-induced macrophage apoptosis, on the other hand, PS-341 could significantly inhibit macrophage necroptosis induced by TNF and pan-caspase inhibitor z-VAD treatment. Remarkably, high-dose of PS-341 showed similar inhibitory effects on macrophage necroptosis comparable to that of kinase inhibition of RIP1 through specific inhibitor Nec-1 or inhibition of RIP3 via specific genetical ablation. Furthermore, the degradation of cellular inhibitor of apoptosis proteins (cIAPs) was suppressed by PS-341, which could antagonize the activation of RIP1 kinase via post-translational mechanism. Further evidences demonstrated reduced levels of both RIP1 and RIP 3 upon PS-341 treatment, concomitantly, a more strong association of RIP1 with cIAPs and less with RIP3 was found following PS-341 treatment, these findings suggested that PS-341 may disrupt the formation of RIP1-RIP3 complex (necrosome) through stabilizing cIAPs. Collectively, our results indicated that the proteasome-mediated degradation of cIAPs could be inhibited by PS-341 and followed by limited RIP1 and RIP3 kinase activities, which were indispensable for necroptosis, thus eliciting a significant necroptosis rescue in BMDMs in vitro. Overall, our study has identified a new role of PS-341 in the cell death of BMDMs and provided a novel insight into the atherosclerotic inflammation caused by proteasome-mediated macrophage necroptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Bortezomib/administración & dosificación , Macrófagos/metabolismo , Macrófagos/patología , Inhibidores de Proteasoma/administración & dosificación , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Animales , Apoptosis/fisiología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Macrófagos/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Necrosis , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/metabolismo
12.
Europace ; 18(7): 1061-8, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26450844

RESUMEN

AIMS: This study sought to investigate electrocardiographic characteristics, electrophysiological features, and radiofrequency ablation in patients with focal atrial tachycardia (AT) originating from the septal mitral annulus. METHODS AND RESULTS: In 13 patients with AT originating from the septal mitral annulus, activation mapping was performed to identify the earliest activation site. Successful ablation was performed through either a transseptal (n = 12) or a retrograde aortic approach (n = 1). As confirmed by electrogram recordings, fluoroscopy, and three-dimensional (3D) mapping, successful ablation sites were located in the anterior paraseptal, mid- to anteroseptal, and posterior septal mitral annulus in eight, three, and two patients, respectively. Foci for all locations demonstrated a negative/positive appearance in lead V1. Mapping in the right atrium demonstrated that the earliest right atrial activation was near the septum (His-bundle region or proximal coronary sinus). The electrograms at the successful ablation sites were fractionated in 9 patients, and presented with an atrial:ventricular ratio of <1 in all 13 patients. There were no complications in any patients and long-term success was achieved in 12 of 13 patients during the 23 ± 6 months following ablation. CONCLUSION: The area surrounding the septal mitral annulus, most commonly the anterior paraseptal, is an unusual, but important site of origin for focal AT, which is associated with a distinctive P-wave morphology and atrial endocardial activation sequence. Radiofrequency ablation of AT originating from the septal mitral annulus, through either a transseptal or a retrograde aortic approach appears to be safe and effective.


Asunto(s)
Apéndice Atrial/cirugía , Fascículo Atrioventricular/fisiopatología , Ablación por Catéter/métodos , Válvula Mitral/fisiopatología , Taquicardia Supraventricular/fisiopatología , Taquicardia Supraventricular/cirugía , Adolescente , Adulto , Niño , China , Electrocardiografía , Fenómenos Electrofisiológicos , Endocardio/fisiopatología , Femenino , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
13.
Zhonghua Nei Ke Za Zhi ; 54(7): 607-11, 2015 Jul.
Artículo en Zh | MEDLINE | ID: mdl-26359023

RESUMEN

OBJECTIVE: The aim of this study was to investigate the differences on origin distribution and radiofrequency ablation characteristics between premature ventricular contractions (PVC) from left and right ventricular. METHODS: A total of 354 frequent PVC patients were enrolled. Two hundred and eighty patients were PVCs with right ventricular origin (group RV) and 74 patients with left ventricular origin (group LV). The age, gender, ablation power, temperature and duration, time of target potential before QRS onset, fluoroscopic time, procedure time and success rate were compared between the two groups. RESULTS: Majority PVCs (79.10%) were of right ventricular origin, in which the most common site was at right ventricular outflow tract (RVOT) (55.93%); whereas, only 20.90% were of left ventricular. There were significantly differences between group RV and group LV in age [(44.7±13.6) yrs vs (49.6±15.9) yrs, P=0.017], gender [male: 35.4%(99) vs 55.4%(41), P=0.002], time of target potential before QRS onset [(37.9±16.2) ms vs (31.3±11.7) ms, P=0.008], procedure time [(85.1±36.9) min vs (100.8±45.5) min, P=0.017], fluoroscopic time [(12.3±9.2) min vs (15.9±10.8) min, P=0.028] and success rate (96.4% vs 89.2%, P=0.012). CONCLUSIONS: Radiofrequency ablation of PVCs was a safe and effective method. Subjects with RV PVCs are younger and more females than subjects with LV PVCs. The radiofrequency ablation for RV PVCs was easier, and the success rate was higher than that for LV PVCs.


Asunto(s)
Ablación por Catéter/métodos , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Derecha/etiología , Complejos Prematuros Ventriculares/terapia , Femenino , Ventrículos Cardíacos , Humanos , Masculino , Resultado del Tratamiento , Obstrucción del Flujo Ventricular Externo , Complejos Prematuros Ventriculares/complicaciones , Complejos Prematuros Ventriculares/fisiopatología
14.
Zhonghua Xin Xue Guan Bing Za Zhi ; 41(7): 563-7, 2013 Jul.
Artículo en Zh | MEDLINE | ID: mdl-24284182

RESUMEN

OBJECTIVE: To explore the relationship between estimated glomerular filtration rate level and clinical characteristics and outcome in coronary artery disease (CAD) patients with normal serum creatinine. METHOD: A total of 548 hospitalized and angiographic CAD patients with normal fasting serum creatinine were enrolled. The kidney function was estimated by using the abbreviated modification of diet in renal disease (MDRD) study equation. Patients were divided into three groups according to eGFR tertiles: high eGFR group (eGFR > 88.15 ml×min(-1)×1.73 m(-2), n = 184); intermediate group ZU(70.30 ml× min(-1)×1.73 m(-2) < eGFR ≤ 88.15 ml×min(-1)×1.73 m(-2), n = 187); low eGFR group (eGFR ≤ 70.30 ml × min(-1)×1.73 m(-2), n = 177). Clinical data and cardiovascular risk factors were recorded after admission and during (14.02 ± 8.31) months follow up. The primary end point was combined major adverse cardiovascular and cerebral events (MACCE) including death, targeted vascular revascularization, non-fatal myocardial infarction, rehospitalization due to unstable angina and heart failure, and transient ischemic attack (TIA) and stroke. RESULTS: Patients in intermediate and low eGFR groups were older, more males, had more severe coronary artery disease, higher level of hsCRP, higher incidence of hypertension, and lower smoking rate than those in high eGFR group (all P < 0.05). A total of 89 MACCE were recorded during follow up. The level of eGFR was significantly lower in patients with MACCE than patients without MACCE [(73.76 ± 19.81) ml×min(-1)×1.73 m(-2) vs. (84.97 ± 23.42) ml×min(-1)×1.73 m(-2), P < 0.05]. Univariate and multivariate Cox regression analysis showed that eGFR was an independent predictor of MACCE in patients with CAD (univariate analysis: RR = 0.99, 95%CI:0.973-0.997, P < 0.05; multivariate analysis: RR = 0.98, 95%CI:0.976-0.998, P < 0.05). Kaplan-Meier survival analysis suggested that patients with low eGFR was linked with a decreased event free survival ratio (log-rank χ(2) = 7.271, P < 0.05). CONCLUSIONS: eGFR level in CAD patients with normal serum creatinine is associated with coronary artery severity, inflammation level and serves as an independent predictor for MACCE in this patient cohort.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico , Tasa de Filtración Glomerular , Anciano , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/fisiopatología , Creatinina/sangre , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico
15.
Heart Rhythm ; 20(5): 668-677, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36634903

RESUMEN

BACKGROUND: There are little data on ventricular arrhythmias (VAs) originating from the right bundle branch (RBB) of the moderator band (MB) (MB-RBB VAs) in a cohort of patients. OBJECTIVE: The purpose of this study was to investigate the electrocardiographic and electrophysiological characteristics of MB-RBB VAs. METHODS: Sixteen patients with MB-RBB VAs and 5 patients with right ventricular (RV) anterior papillary muscle (APM) VAs (RV-APM VAs) were studied under the guidance of intracardiac echocardiography. RESULTS: The MB-RBB VAs group demonstrated a typical left bundle branch block pattern with left superior axis deviation and a narrower QRS complex during VAs (P < .001) as compared with the RV-APM VAs group. Furthermore, the MB-RBB VAs group had a shorter rS interval, a sharper slope of the S wave downstroke without notching in leads V1 and V2, and a shorter r wave duration in lead V2. A leading RBB potential at the target during VAs was observed for all patients in the MB-RBB VAs group, which was also present during sinus rhythm for all patients, except for 2 with RBB block at baseline. Ablation of the leading RBB potential effectively eliminated the arrhythmia. In the RV-APM VAs group, no Purkinje potential at the target was identified in any patient during VAs. CONCLUSION: QRS morphology of MB-RBB VAs is characterized by a typical left bundle branch block pattern with a relatively narrow QRS complex, short r wave and rS durations, and a sharp S wave downstroke without notching in leads V1 and V2. Mapping and ablation of the leading RBB potential are effective in eliminating VAs.


Asunto(s)
Ablación por Catéter , Taquicardia Ventricular , Humanos , Bloqueo de Rama , Arritmias Cardíacas , Electrocardiografía , Sistema de Conducción Cardíaco
16.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 24(12): 734-8, 2012 Dec.
Artículo en Zh | MEDLINE | ID: mdl-23168202

RESUMEN

OBJECTIVE: To explore the relationship between reduced left ventricular ejection fraction (LVEF) and characteristics of coronary artery disease (CAD) and investigate the association between reduced LVEF and cardiovascular prognosis. METHODS: A total of 677 hospitalized patients with angiographic CAD were enrolled. All patients' clinical data were recorded. LVEF were measured, high sensitive C-reactive protein (hs-CRP), white blood cell (WBC) and classic cardiovascular risk factors were recorded after admission. All patients were followed up from admission. The primary end point was combination occurrence of major adverse cardiovascular and cerebral events (MACCE), including death, targeted vascular revascularization, non-fatal myocardial infarction and rehospitalization due to unstable angina or heart failure, transient ischemic attack or stroke. RESULTS: All patients were tracked for (15±12) months, and patients were divided into normal LVEF group (LVEF≥0.50, n=585) and reduced LVEF group (LVEF<0.50, n=92) according to LVEF level. Compared with normal LVEF group, reduced LVEF group had more severe coronary stenosis (Gensini score: 62.85±41.45 vs. 47.68±33.26, P<0.05), a higher level of WBC and hs-CRP (WBC: 7.60±2.71 ×10(9)/L vs. 7.09±2.13 ×10(9)/L, hs-CRP: 5.68±3.97 mg/L vs. 3.97±3.75 mg/L, both P<0.05). A total of 146 MACCE occurred during follow-up periods. Compared with no-MACCE group, LVEF levels were significantly lower in MACCE group (0.576±0.113 vs. 0.603±0.101) and there were a higher level of hs-CRP and Gensini score in MACCE group (hs-CRP: 5.26±3.99 mg/L vs. 3.91±3.72 mg/L, Gensini score: 53.72±35.50 vs. 48.63±34.59, all P<0.05). Moreover, both of univariate and multivariate Cox regression analysis indicated LVEF be an independent predictor of MACCE in patients with CAD [univariate: relative risk (RR)=0.974, 95% confidence interval (95%CI) 0.960 to 0.988, P=0.000; multivariate: RR=0.979, 95%CI 0.961 to 0.998, P=0.033]. Kaplan-Meier analysis suggested that patients with reduced LVEF had an increased MACCE occurrence (χ(2)=14.56, P<0.05). CONCLUSION: LVEF level may be associated with coronary artery severity, and could be independently predict the prognosis of CAD.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/fisiopatología , Volumen Sistólico , Función Ventricular Izquierda , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos
17.
Int J Med Mushrooms ; 24(11): 73-82, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36374950

RESUMEN

The objective of the current study is to reveal the influence of particle size of ground Schizophyllum commune and its extracted dietary fiber (DF) on physicochemical and antioxidant properties. Sch. commune powder and the extracted DF was ground by regular and superfine grinding, and their particle sizes were determined using laser diffraction particle size analyzer. The results indicated that superfine grinding could significantly pulverize DF particles to micro-scale; the particle size distribution presented a Gaussian distribution. The soluble DF in Sch. commune was increased effectively with superfine grinding. Sub-micronized insoluble DF showed increased total phenolic content (TPC) and ferric reducing antioxidant power (FRAP). Moreover, with particle size reduction, the oil binding capacity (OBC), nitrite ion absorption capacity (NIAC), cation-exchange capacity (CEC), cholesterol absorption capacity (CAC), and Pb ion adsorption capacity were significantly (p < 0.05) increased and the water retention capacity (WRC), swelling capacity (SC) and Cu, Zn ions adsorption capacity had no significant changes. A kind of health beneficial DF with higher soluble DF content, OBC, NIAC, CEC, CAC, Pb ion adsorption capacity and antioxidant activity (TPC and FRAP) was obtained through superfine grinding. Sch. commune DF could be potentially used as an ingredient for functional food and nutraceuticals.


Asunto(s)
Agaricales , Schizophyllum , Antioxidantes/química , Agaricales/metabolismo , Plomo , Fibras de la Dieta/análisis , Fenoles/química
18.
Materials (Basel) ; 15(13)2022 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-35806848

RESUMEN

In this paper, first principles method was adopted to investigate the point defects, Vanadium-related defects and defect combinations (vacancy (V), substitutional (S) and/or interstitial (I)) in molybdenum ß-Mo2C and explore the use of first principles calculation data in analysing the link between different carbides and the effects of doping elements. Supercell models with different defect types were established and optimized, and the formation energy data of defects was developed. The structure evolution during the optimization process is analysed in detail to establish the main characteristics of changes and the relevant electronic properties. The data for different types of intrinsic defects and combined defects complexes was developed and key results is analysed. The results show that carbon vacancy (VC) is stable but does not inevitably exist in pure ß-Mo2C. Interstitial site II is a very unstable position for any type of atoms (Mo, V and C), and analysis of the structure evolution shows that the atom always moves to the interface area near the interstitial site I between two layers. In particular, a C atom can expand the lattice structure when it exists between the layer interfaces. One type of the defects studied, the substitution of Mo with V (designated as 'SV-Mo'), is the most stable defect among all single point defects. The data for defect complexes shows that the combination of multiple SV-Mo defects in the super cell being more stable than the combination of other defects (e.g., 'VMo+IC', 'SV-Mo+VC'). The data with increasing SV-Mo in (Mo, V)2C system is developed, and typical data (e.g., formation energy) for Mo-rich carbides and V carbides are correlated and the potential of the data in analysing transition of different carbides is highlighted. The relevance of using first principles calculation data in the studying of V-doping and the complex carbides (V- and Mo-rich carbides) evolution in different materials systems and future focus of continuous work is also discussed.

19.
Cell Death Dis ; 13(2): 121, 2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35136037

RESUMEN

Upon vascular injury, vascular smooth muscle cells (VSMCs) change from a contractile phenotype to a synthetic phenotype, thereby leading to atherogenesis and arterial restenosis. Myocardin (MYOCD) is essential for maintaining the contractile phenotype of VSMCs. Deletion of MYOCD in VSMCs triggers autophagy. However, the molecular mechanism underlying the effect of MYOCD on autophagy is not clear. In this study, knockdown of MYOCD in human aortic VSMCs (HA-VSMCs) triggered autophagy and diminished the expression of SMC contractile proteins. Inhibition of autophagy in MYOCD-knockdown cells restored the expression of contractile proteins. MYOCD activated the transcription of miR-30a by binding to the CArG box present in its promoter, as confirmed by luciferase reporter and chromatin immune coprecipitation assays, while miR-30a decreased the expression of autophagy protein-6 (ATG6, also known as beclin1) by targeting its 3'UTR. Restoring the expression of miR-30a in MYOCD-knockdown cells upregulated the levels of contractile proteins. Treatment of VSMCs with platelet-derived growth factor type BB (PDGF-BB) resulted in the transformation of VSMCs to a proliferative phenotype. A low level of miR-30a was observed in PDGF-BB-treated HA-VSMCs, and re-expression of miR-30a led to a decrease in proliferative marker expression. Furthermore, using a wire injury mouse model, we found that miR-30a expression was significantly downregulated in the arterial tissues of mice and that restoration of miR-30a expression at the injured site abolished neointimal formation. Herein, MYOCD could inhibit autophagy by activating the transcription of miR-30a and that miR-30a-mediated autophagy defects could inhibit intimal hyperplasia in a carotid arterial injury model.


Asunto(s)
Beclina-1 , MicroARNs , Músculo Liso Vascular , Proteínas Nucleares , Transactivadores , Autofagia/genética , Becaplermina/farmacología , Beclina-1/metabolismo , Proliferación Celular , Células Cultivadas , Proteínas Contráctiles/genética , Humanos , MicroARNs/metabolismo , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Proteínas Nucleares/metabolismo , Fenotipo , Transactivadores/metabolismo
20.
Sci Rep ; 12(1): 11119, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35778441

RESUMEN

With the increase in extremely low birth weight (ELBW) infants, their outcome attracted worldwide attention. However, in China, the related studies are rare. The hospitalized records of ELBW infants discharged from twenty-six neonatal intensive care units in Guangdong Province of China during 2008-2017 were analyzed. A total of 2575 ELBW infants were enrolled and the overall survival rate was 55.11%. From 2008 to 2017, the number of ELBW infants increased rapidly from 91 to 466, and the survival rate improved steadily from 41.76% to 62.02%. Increased survival is closely related to birth weight (BW), regional economic development, and specialized hospital. The incidence of complications was neonatal respiratory distress syndrome (85.2%), oxygen dependency at 28 days (63.7%), retinopathy of prematurity (39.3%), intraventricular hemorrhage (29.4%), necrotizing enterocolitis (12.0%), and periventricular leukomalacia (8.0%). Among the 1156 nonsurvivors, 90.0% of infants died during the neonatal period (≤ 28 days). A total of 768 ELBW infants died after treatment withdrawal, for reasons of economic and/or poor outcome. The number of ELBW infants is increasing in Guangdong Province of China, and the overall survival rate is improving steadily.


Asunto(s)
Enterocolitis Necrotizante , Enfermedades del Prematuro , Estudios de Cohortes , Enterocolitis Necrotizante/epidemiología , Humanos , Lactante , Mortalidad Infantil , Recien Nacido con Peso al Nacer Extremadamente Bajo , Recién Nacido , Enfermedades del Prematuro/epidemiología
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