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1.
Heliyon ; 10(4): e26054, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38404821

RESUMEN

An effective wave absorbing Nano-Ni/carbon nanotubes (CNTs) composite film was developed by electrodeposition using an anodic aluminum oxide (AAO)/CNTs electrode. Scanning electron microscopy images confirmed the uniform dispersion of Ni nano-particles within the CNTs, and the particle diameter increasing from 20 nm to 100 nm as the deposition time increased. XRD test results revealed that the crystal phase of the Ni nano-particles remained unchanged during different deposition time, exhibiting a Face Center Cubic (fcc) structure. The microwave electromagnetic properties of the film were evaluated using a vector network analyzer, and the return loss curve demonstrated that the Ni nano-particles/CNTs composite exhibited exceptional wave absorption capabilities. The composite film showed an effective absorption width of 13 GHz (4-17 GHz) and achieved a minimum reflection loss (RL) of -17 dB at 14 GHz.

2.
J Plant Physiol ; 280: 153886, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36493670

RESUMEN

Photooxidation is the major physiological performance of the Lagerstroemia indica chlorosis mutant gl1 under field conditions. The mechanisms of the progressive symptoms of oxidative damage from the lower older leaves to the upper mature leaves are complicated and still unclear. The aim of this work was to investigate the physiological mechanisms of oxidative stress from the perspective of the photosynthetic metabolites. The phytosynthetic metabolites of gl1 mutant changed significantly compared to wild type (WT) L. indica, such as by increasing phenolics, decreasing soluble sugar, protein and ascorbate, and redistributing antioxidant enzyme activities. The co-accumulation of phenolics and guaiacol-POD in gl1 mutant promote the removal of H2O2, as well the increase of phenoxyl radicals levels. Furthermore, the ion balance was significantly disturbed and Fe accumulated the most among these fluctuating nutrients in the leaves of gl1 mutant. The accumulated Fe was found neither in the chloroplasts nor in the cell wall of the leaves and became unshielded Fe, which favors the Fenton/Haber-Weiss reaction and stabilizes the phenoxyl radicals in metal complexation. The results suggested that the increase of phenolics and Fe accumulation were obviously involved in oxidative damage of gl1 mutant.


Asunto(s)
Anemia Hipocrómica , Ferroptosis , Lagerstroemia , Lagerstroemia/genética , Lagerstroemia/metabolismo , Peróxido de Hidrógeno/metabolismo , Estrés Oxidativo , Antioxidantes/metabolismo , Anemia Hipocrómica/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo
3.
Nucleic Acids Res ; 50(20): 11529-11549, 2022 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-36330957

RESUMEN

Increasing studies have revealed that a subset of circular RNAs (circRNAs) harbor an open reading frame and can act as protein-coding templates to generate functional proteins that are closely associated with multiple physiological and disease-relevant processes, and thus proper regulation of synthesis of these circRNA-derived proteins is a fundamental cellular process required for homeostasis maintenance. However, how circRNA translation initiation is coordinated by different trans-acting factors remains poorly understood. In particular, the impact of different eukaryotic translation initiation factors (eIFs) on circRNA translation and the physiological relevance of this distinct regulation have not yet been characterized. In this study, we screened all 43 Drosophila eIFs and revealed the conflicting functions of eIF3 subunits in the translational control of the translatable circRNA circSfl: eIF3 is indispensable for circSfl translation, while the eIF3-associated factor eIF3j is the most potent inhibitor. Mechanistically, the binding of eIF3j to circSfl promotes the disassociation of eIF3. The C-terminus of eIF3j and an RNA regulon within the circSfl untranslated region (UTR) are essential for the inhibitory effect of eIF3j. Moreover, we revealed the physiological relevance of eIF3j-mediated circSfl translation repression in response to heat shock. Finally, additional translatable circRNAs were identified to be similarly regulated in an eIF3j-dependent manner. Altogether, our study provides a significant insight into the field of cap-independent translational regulation and undiscovered functions of eIF3.


Asunto(s)
Factor 3 de Iniciación Eucariótica , ARN Circular , Citoplasma/metabolismo , Factor 3 de Iniciación Eucariótica/metabolismo , Biosíntesis de Proteínas , ARN Circular/genética , Drosophila , Animales , Proteínas de Drosophila/metabolismo
4.
Nat Commun ; 13(1): 5769, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-36182935

RESUMEN

Numerous RNAs are exported from the nucleus, abnormalities of which lead to cellular complications and diseases. How thousands of circular RNAs (circRNAs) are exported from the nucleus remains elusive. Here, we provide lines of evidence to demonstrate a link between the conserved Exportin 4 (XPO4) and nuclear export of a subset of circRNAs in metazoans. Exonic circRNAs (ecircRNAs) with higher expression levels, larger length, and lower GC content are more sensitive to XPO4 deficiency. Cellular insufficiency of XPO4 leads to nuclear circRNA accumulation, circRNA:DNA (ciR-loop) formation, linear RNA:DNA (liR-loop) buildup, and DNA damage. DDX39 known to modulate circRNA export can resolve ciR-loop, and splicing factors involved in the biogenesis of circRNAs can also affect the levels of ciR-loop. Testis and brain are two organs with high abundance of circRNAs, and insufficient XPO4 levels are detrimental, as Xpo4 heterozygous mice display male infertility and neural phenotypes. Increased levels of ciR-loop, R-loop, and DNA damage along with decreased cell numbers are observed in testis and hippocampus of Xpo4 heterozygotes. This study sheds light on the understandings of mechanism of circRNA export and reveals the significance of efficient nuclear export of circRNAs in cellular physiology.


Asunto(s)
ARN Circular , ARN , Animales , Carioferinas/genética , Carioferinas/metabolismo , Masculino , Ratones , ARN/genética , ARN/metabolismo , Empalme del ARN/genética , Factores de Empalme de ARN/metabolismo , ARN Circular/genética
6.
Nucleic Acids Res ; 49(11): 6296-6314, 2021 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-34107019

RESUMEN

Metal-induced genes are usually transcribed at relatively low levels under normal conditions and are rapidly activated by heavy metal stress. Many of these genes respond preferentially to specific metal-stressed conditions. However, the mechanism by which the general transcription machinery discriminates metal stress from normal conditions and the regulation of MTF-1-meditated metal discrimination are poorly characterized. Using a focused RNAi screening in Drosophila Schneider 2 (S2) cells, we identified a novel activator, the Drosophila gawky, of metal-responsive genes. Depletion of gawky has almost no effect on the basal transcription of the metallothionein (MT) genes, but impairs the metal-induced transcription by inducing the dissociation of MTF-1 from the MT promoters and the deficient nuclear import of MTF-1 under metal-stressed conditions. This suggests that gawky serves as a 'checkpoint' for metal stress and metal-induced transcription. In fact, regular mRNAs are converted into gawky-controlled transcripts if expressed under the control of a metal-responsive promoter, suggesting that whether transcription undergoes gawky-mediated regulation is encrypted therein. Additionally, lack of gawky eliminates the DNA binding bias of MTF-1 and the transcription preference of metal-specific genes. This suggests a combinatorial control of metal discrimination by gawky, MTF-1, and MTF-1 binding sites.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Metales/toxicidad , Factores de Transcripción/metabolismo , Activación Transcripcional , Transporte Activo de Núcleo Celular , Animales , Línea Celular , Núcleo Celular/metabolismo , Cobre/toxicidad , Proteínas de Drosophila/genética , Proteínas de Drosophila/fisiología , Drosophila melanogaster/efectos de los fármacos , Drosophila melanogaster/metabolismo , Metalotioneína/genética , Regiones Promotoras Genéticas , Interferencia de ARN , Empalme del ARN , Estrés Fisiológico/genética , Factor de Transcripción MTF-1
7.
Noncoding RNA Res ; 6(2): 70-79, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33898883

RESUMEN

Long noncoding RNAs (lncRNAs), defined as untranslated and tightly-regulated transcripts with a length exceeding 200 nt, are common outputs of the eukaryotic genome. It is becoming increasingly apparent that many lncRNAs likely serve as important regulators in a variety of biological processes. In particular, some of them accumulate in the nucleus and function in diverse nuclear events, including chromatin remodeling, transcriptional regulation, RNA processing, DNA damage repair, etc. Here, we unite recent progresses on the functions of nuclear lncRNAs and provide insights into the future research directions of this field.

8.
Sci China Life Sci ; 64(5): 784-794, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32815066

RESUMEN

As a class of powerful molecular tool, antisense oligonucleotides (ASOs) are not only broadly used in protein and RNA biology, but also a highly selective therapeutic strategy for many diseases. Although the concept that ASO reagents only reduce expression of the targeted gene in a post-transcriptional manner has long been established, the effect and mechanism of ASO reagents on RNA polymerase II (Pol II) transcription are largely unknown. This raised question is particularly important for the appropriate use of ASOs and the valid interpretation of ASO-mediated experiments. In this study, our results show that linear RNA ASO attenuates transcription of nascent transcripts by inducing premature transcription termination which is combinatorially controlled by Integrator, exosome, and Rat1 in Drosophila. However, circular RNA (circRNA) ASO transfection does not affect transcription activity of the encoded gene. These data suggest that the ASO technique can be applied to study a circRNA-mediated but not linear RNA-mediated function for its encoded gene locus.


Asunto(s)
Exosomas/metabolismo , Oligonucleótidos Antisentido/química , ARN Circular/fisiología , Animales , Células Cultivadas , Drosophila , Proteínas de Drosophila/metabolismo , ARN Polimerasa II/genética , Procesamiento Postranscripcional del ARN , ARN Circular/genética , ARN Mensajero/genética , Terminación de la Transcripción Genética
9.
Comput Methods Programs Biomed ; 141: 111-117, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28241962

RESUMEN

In recent years, numerous adaptive filtering techniques have been developed to suppress the chest compression (CC) artifact for reliable analysis of the electrocardiogram (ECG) rhythm without CC interruption. Unfortunately, the result of rhythm diagnosis during CCs is still unsatisfactory in many studies. The misclassification between corrupted asystole (ASY) and corrupted ventricular fibrillation (VF) is generally regarded as one of the major reasons for the poor performance of reported methods. In order to improve the diagnosis of VF/ASY corrupted by CCs, a novel method combining a least mean-square (LMS) filter and an amplitude spectrum area (AMSA) analysis was developed based only on the analysis of the surface of the corrupted ECG episode. This method was tested on 253 VF and 160 ASY ECG samples from subjects who experienced cardiac arrest using a porcine model and was compared with six other algorithms. The validation results indicated that this method, which yielded a satisfactory result with a sensitivity of 93.3%, a specificity of 96.3% and an accuracy of 94.8%, is superior to the other reported techniques. After improvement using the human ECG records in real cardiopulmonary resuscitation (CPR) scenarios, the algorithm is promising for corrupted VF/ASY detection with no hardware alterations in clinical practice.


Asunto(s)
Reanimación Cardiopulmonar , Electrocardiografía , Paro Cardíaco/diagnóstico , Fibrilación Ventricular/diagnóstico , Animales , Artefactos , Diagnóstico Diferencial , Porcinos
10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 33(4): 747-54, 2016 Aug.
Artículo en Chino | MEDLINE | ID: mdl-29714916

RESUMEN

On account of the mechanical disturbance of external chest pressing to electrocardiogram(ECG)signal,the ECG rhythm cannot be identified reliably during the cardio-pulmonary resuscitation period.Whereas the possibility of successful resuscitation will be lowered due to interrupted external chest pressing,a new filtering algorithm,enhanced leastmean-square(eLMS)algorithm,was proposed and developed in our laboratory.The algorithm can filter the disturbance of external chest pressing without the support of hardware reference signal and correctly identify ventricular fibrillation(VF)rhythm and normal sinus rhythm in case of uninterrupted external chest pressing.Without other reference signals,this algorithm realizes filtering only through the interrupted electrocardiograma(cECG)signal.It was verified with ECG signal and disturbance signal under different signal to noise ratios and contrasted with other mature algorithms.The verification results showed that the identification effect of eLMS was superior to those of others under different signal to noise ratios.Furthermore,ECG rhythm can be correctly identified only through cECG signal.This algorithm not only reduces the research and development(R&D)costs of automated external defibrillator but also raises the identification accuracy of ECG rhythm and the possibility of successful resuscitation.


Asunto(s)
Algoritmos , Reanimación Cardiopulmonar , Electrocardiografía , Fibrilación Ventricular/diagnóstico , Artefactos , Desfibriladores , Paro Cardíaco/terapia , Humanos , Presión , Relación Señal-Ruido , Fibrilación Ventricular/fisiopatología
11.
Med Biol Eng Comput ; 53(6): 487-97, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25735437

RESUMEN

Chest compression (CC) is a significant emergency medical procedure for maintaining circulation during cardiac arrest. Although CC produces the necessary blood flow for patients with heart arrest, improperly deep CC will contribute significantly to the risk of chest injury. In this paper, an optimal CC closed-loop controller for a mechanical chest compressor (OCC-MCC) was developed to provide an effective trade-off between the benefit of improved blood perfusion and the risk of ribs fracture. The trade-off performance of the OCC-MCC during real automatic mechanical CCs was evaluated by comparing the OCC-MCC and the traditional mechanical CC method (TMCM) with a human circulation hardware model based on hardware simulations. A benefit factor (BF), risk factor (RF) and benefit versus risk index (BRI) were introduced in this paper for the comprehensive evaluation of risk and benefit. The OCC-MCC was developed using the LabVIEW control platform and the mechanical chest compressor (MCC) controller. PID control is also employed by MCC for effective compression depth regulation. In addition, the physiological parameters model for MCC was built based on a digital signal processor for hardware simulations. A comparison between the OCC-MCC and TMCM was then performed based on the simulation test platform which is composed of the MCC, LabVIEW control platform, physiological parameters model for MCC and the manikin. Compared with the TMCM, the OCC-MCC obtained a better trade-off and a higher BRI in seven out of a total of nine cases. With a higher mean value of cardiac output (1.35 L/min) and partial pressure of end-tidal CO2 (15.7 mmHg), the OCC-MCC obtained a larger blood flow and higher BF than TMCM (5.19 vs. 3.41) in six out of a total of nine cases. Although it is relatively difficult to maintain a stable CC depth when the chest is stiff, the OCC-MCC is still superior to the TMCM for performing safe and effective CC during CPR. The OCC-MCC is superior to the TMCM in performing safe and effective CC during CPR and can be incorporated into the current version of mechanical CC devices for high quality CPR, in both in-hospital and out-of-hospital CPR settings.


Asunto(s)
Circulación Sanguínea/fisiología , Reanimación Cardiopulmonar/instrumentación , Modelos Cardiovasculares , Fracturas de las Costillas/prevención & control , Procesamiento de Señales Asistido por Computador/instrumentación , Adulto , Reanimación Cardiopulmonar/efectos adversos , Humanos , Presión Parcial , Volumen de Ventilación Pulmonar
12.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 24(6): 323-6, 2012 Jun.
Artículo en Chino | MEDLINE | ID: mdl-22681658

RESUMEN

OBJECTIVE: To describe a portable life support device for transportation of pre-hospital patients with critical illness. METHODS: The characteristics and requirements for urgent management during transportation of critically ill patients to a hospital were analyzed. With adoption of the original equipment, with the aid of staple of the art soft ware, the overall structure, its installation, fixation, freedom from interference, operational function were studied, and the whole system of life support and resuscitation was designed. RESULTS: The system was composed by different modules, including mechanical ventilation, transfusion, aspiration, critical care, oxygen supply and power supply parts. The system could be fastened quickly to a stretcher to form portable intensive care unit (ICU), and it could be carried by different size vehicles to provide nonstop treatment by using power supply of the vehicle, thus raising the efficiency of urgent care. CONCLUSION: With characteristics of its small size, lightweight and portable, the device is particularly suitable for narrow space and extreme environment.


Asunto(s)
Servicios Médicos de Urgencia , Cuidados para Prolongación de la Vida/instrumentación , Transporte de Pacientes , Cuidados Críticos , Diseño de Equipo , Humanos
13.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 21(9): 521-4, 2009 Sep.
Artículo en Chino | MEDLINE | ID: mdl-19751558

RESUMEN

OBJECTIVE: To satisfy the requirements of pre-hospital and first aid at scene for critical patient, rapid transportation, and nonstop treatment in hospital, this paper describes a design of a stretcher integrated first-aid system (SIFAS), which can provide seamless link between pre-hospital and in-hospital first aid. METHODS: With the requirements of integration and informationization, related functional modules of the former invented SIFAS were redesigned with principle of miniaturization. Adhering to the principle of best man-machine performance, systemic structural characteristic was studied. Aiming at achieving the best maneuverability but with lightest weight, the materials and processing technology of the framework were modified and improved. RESULTS: The SIFAS designed possessed good flexibility, it could be carried on pushed, and it could be attached to many carriers, with shortened time, and continuous first aid could be realized, and waiting time for first aid was greatly reduced. CONCLUSION: The SIFAS provides a possibility for establishing a emergency green path for pre-hospital and in-hospital first aid, and it improves emergency of the patient and quick response of relevant medical institutions.


Asunto(s)
Medicina de Emergencia/instrumentación , Enfermedad Crítica , Diseño de Equipo , Primeros Auxilios , Humanos
14.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 25(11): 1020-2, 2005 Nov.
Artículo en Chino | MEDLINE | ID: mdl-16355621

RESUMEN

OBJECTIVE: To observe the therapeutic effect of Huoxue Jieyu decoction (HJD) on patients with depression after craniotomy. METHODS: Ninety patients were randomly divided into 2 groups according to the sequence of their consultation. The 45 patients in the treated group were treated with conventional symptomatic treatment plus oral administration of HJD, and the 38 patients in the control group were treated in the same way but with chlorimipramine (anafranil) instead of HJD. Hamilton depression (HAMD) scores before and after treatment, occurrence of adverse effects and long-term therapeutic effect of treatment were observed. RESULTS: The score of HAMD was insignificantly different in 2 groups before and after treatment (P >0.05), but the occurrence of adverse effects between them was significantly different (P < 0.01). CONCLUSION: The therapeutic effect of HJD on depression was similar to that of anafranil, but HJD has less adverse effect and more stabilized long-term effect.


Asunto(s)
Craneotomía/efectos adversos , Trastorno Depresivo/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Fitoterapia , Adolescente , Adulto , Trastorno Depresivo/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/tratamiento farmacológico
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