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1.
Sensors (Basel) ; 24(5)2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38475126

RESUMEN

Underground displacement monitoring is a crucial means of preventing geological disasters. Compared to existing one-dimensional methods (measuring only horizontal or vertical displacement), the underground displacement three-dimensional measurement method and monitoring system proposed by the author's research team can more accurately reflect the internal movement of rock and soil mass, thereby improving the timeliness and accuracy of geological disaster prediction. To ensure the reliability and long-term operation of the underground displacement three-dimensional monitoring system, this article further introduces low-power design theory and Bluetooth wireless transmission technology into the system. By optimizing the power consumption of each sensing unit, the current during the sleep period of a single sensing unit is reduced to only 0.09 mA. Dynamic power management technology is employed to minimize power consumption during each detection cycle. By using Bluetooth wireless transmission technology, the original wired communication of the system is upgraded to a relay-type wireless network communication, effectively solving the problem of the entire sensing array's operation being affected when a single sensing unit is damaged. These optimized designs not only maintain monitoring accuracy (horizontal and vertical displacement errors not exceeding 1 mm) but also enable the monitoring system to operate stably for an extended period under harsh weather conditions.

2.
Opt Express ; 30(15): 26544-26556, 2022 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-36236843

RESUMEN

A multifunctional design based on vanadium dioxide (VO2) metamaterial structure is proposed. Broadband absorption, linear-to-linear (LTL) polarization conversion, linear-to-circular (LTC) polarization conversion, and total reflection can be achieved based on the insulator-to-metal transition (IMT) of VO2. When the VO2 is in the metallic state, the multifunctional structure can be used as a broadband absorber. The results show that the absorption rate exceeds 90% in the frequency band of 2.17 - 4.94 THz, and the bandwidth ratio is 77.8%. When VO2 is in the insulator state, for the incident terahertz waves with a polarization angle of 45°, the structure works as a polarization converter. In this case, LTC polarization conversion can be obtained in the frequency band of 0.1 - 3.5 THz, and LTL polarization conversion also can be obtained in the frequency band of 3.5 - 6 THz, especially in the 3.755 - 4.856 THz band that the polarization conversion rate is over 90%. For the incident terahertz waves with a polarization angle of 0°, the metamaterial structure can be used as a total reflector. Additionally, impacts of geometrical parameters, incidence angle and polarization angle on the operating characteristics have also been investigated. The designed switchable multifunctional metasurfaces are promising for a wide range of applications in advanced terahertz research and smart applications.

3.
Appl Opt ; 61(35): 10451-10457, 2022 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-36607105

RESUMEN

In this paper, a novel, to the best of our knowledge, polymer-based negative curvature ring-core fiber (NC-RCF) is proposed and investigated. The hollow-core NC-RCF is composed of TOPAS as background material. The inner and outer negative curvature structure layers are connected to the annular area, and the orbital angular momentum (OAM) modes can propagate in the annular core. In the frequency region of 1.0-1.5 THz, the designed NC-RCF can stably transmit 82 OAM modes. Investigation results indicate that the effective refractive index differences between the corresponding HE and EH modes are above 10-4. The confinement losses of EH or HE modes are smaller than 10-8 d B/m, and the dispersion variations are lower than 0.31 ps/THz/cm. Effective mode areas are larger than 5.14m m 2. Additionally, the highest mode purity of all vector modes is 99.78%. In addition, modal birefringence, also known as the walk-off length, has also been discussed. All these operation performances indicate that the designed NC-RCF make contributions to the optical communication systems.

4.
Sensors (Basel) ; 22(5)2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35270871

RESUMEN

Landslide is a very common and destructive geo-hazard, and displacement monitoring of it is integral for risk assessment and engineering prevention. Given the shortcomings of current landslide displacement monitor technologies, a new three-dimensional underground displacement monitoring technology is proposed based on the double mutual inductance voltage contour method. The underground displacement measuring device mainly consists of an information processing unit and sensing array, connected by power and RS-485 communication lines. An underground displacement measurement model to convert the double mutual inductance voltages and the inter-axis angle into the relative displacement between adjacent sensing units is established based on the interval-interpolation and contour-modeling. Under the control of the information processing unit, the relative displacement between any two adjacent sensing units can be calculated through the underground displacement measurement model, so as to obtain the total displacement from underground depth to surface, and the measurement data can be further sent to the Internet of things cloud platform through the 4G module; thus the remote real-time monitoring of underground displacement three-dimensional measurement for the rock and soil mass from underground depth to the surface is realized. The measurement model is verified by building an experimental platform to simulate the underground displacement of rock and soil mass. The experimental results show that for each measuring unit, when the horizontal displacement and vertical displacement are within the measurement range of 0-50 mm, the maximum measurement error will not exceed 1 mm, which can meet the accuracy requirements of underground displacement monitoring of landslide.

5.
Opt Lett ; 46(3): 604, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33528419

RESUMEN

This publisher's note contains corrections to Opt. Lett.46, 290 (2021)OPLEDP0146-959210.1364/OL.412229.

6.
Opt Lett ; 46(2): 290-293, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33449010

RESUMEN

At present, most of the gradient metasurfaces used to construct surface plasmon polaritons (SPPs)/spoof SPPs (SSPs) couplers are usually compact metal antennas working under reflection and transmission. In reflection mode, meta-couplers link propagating waves and surface waves (SWs), and SWs will undergo significant scattering before coupling to an Eigen SPP in the target system. In transmission mode, metal meta-couplers will encounter complex multilayer designing at the microwave/terahertz region and metal absorption loss at optical frequencies. In this Letter, to the best of our knowledge, a novel design using dielectric gradient metasurfaces instead of metal metasurface couplers is proposed to excite broadband SSPs on the metal groove array. We demonstrate that the well-designed phase dielectric gradient metasurface converts the normal incident terahertz wave to the predetermined angle in the dielectric substrate and then excites the broadband SSPs with the transmission coupling between the dielectric meta-coupler and SSPs surface. This research may open up new avenues in simple and broadband plane dielectric meta-couplers for SSPs in ultra-thin and compact functional devices for versatile applications.

7.
Sensors (Basel) ; 20(6)2020 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-32197396

RESUMEN

Deep displacement monitoring of rock and soil mass is the focus of current geological hazard research. In the previous works, we proposed a geophysical deep displacement characteristic information detection method by implanting magneto-electric sensing arrays in boreholes, and preliminarily designed the sensor prototype and algorithm of deep displacement three-dimensional (3D) measurement. On this basis, we optimized the structure of the sensing unit through 3D printing and other technologies, and improved the shape and material parameters of the permanent magnet after extensive experiments. Through in-depth analysis of the experimental data, based on the data query algorithm and the polynomial least square curve fitting theory, a new mathematical model for 3D measurement of deep displacement has been proposed. By virtue of it, the output values of mutual inductance voltage, Hall voltage and tilt measuring voltage measured by the sensing units can be converted into the variations of relative horizontal displacement, vertical displacement and axial tilt angle between any two adjacent sensing units in real time, and the measuring errors of horizontal and vertical displacement are tested to be 0-1.5 mm. The combination of structural optimization and measurement method upgrading extends the measurement range of the sensing unit from 0-30 mm to 0-50 mm. It shows that our revised deep displacement 3D measuring sensor can better meet the needs of high-precision monitoring at the initial stage of rock and soil deformation and large deformation monitoring at the rapid change and imminent-sliding stage.

8.
Biogerontology ; 20(6): 741-761, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31473864

RESUMEN

Aging is a progressive decline of physiological function in tissue and organ accompanying both accumulation of DNA damage and reduction of non-coding DNA. Peripheral non-coding DNA/heterochromatin has been proposed to protect the genome and centrally-located protein-coding sequences in soma and male germ cells against radiation and the invasion of exogenous nucleic acids. Therefore, this review summarizes the reduction of non-coding DNA/heterochromatin (including telomeric DNA and rDNA) and DNA damage accumulation during normal physiological aging and in various aging-related diseases. Based on analysis of data, it is found that DNA damage accumulation is roughly negatively correlated with the reduction of non-coding DNA and therefore speculated that DNA damage accumulation is likely due to the reduction of non-coding DNA protection in genome defense during aging. Therefore, it is proposed here that means to increase the total amount of non-coding DNA and/or heterochromatin prior to the onset of these diseases could potentially better protect the genome and protein-coding DNA, reduce the incidence of aging-related diseases, and thus lead to better health during aging.


Asunto(s)
Envejecimiento/genética , Daño del ADN , ADN/genética , Cardiopatías/genética , Heterocromatina/genética , Humanos , Neoplasias/genética , Telómero
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(3): 681-5, 2016 Mar.
Artículo en Zh | MEDLINE | ID: mdl-27400505

RESUMEN

To investigate the Terahertz's application prospect, corn, wheat husk and reed were used to detect their Terahertz Time Domain Spectroscopy, and be compared with that of cellulose powder. The experimental results show that all of their absorption peaks exist at 1.75, 1.62, 1.1, and 0.7 THz. Absorption intensity of cellulose powder, corn, wheat husk and reed were compared in some frequencies points. It finds that corn, wheat husk and reed have higher absorption intensity than cellulose powder in early frequency domain. However, absorption intensity of cellulose powder is the strongest at 1.62 THz. Cellulose content in corn, wheat husk and reed were detected by using the method of chemical analysis. The peaks of absorption coefficient are related to their cellulose content at this frequency. It shows that plant cellulose occur lattice vibration in the frequency. Deformation, bending, flexing, and other changes appear to their functional keys. Quantum chemical calculation was carried out by using density functional theory to cellulose and the structure diagram of cellulose molecular formula was obtained. It also finds some absorption peaks exist at 0.7, 1.1, and 1.75 THz. Characterization of cellulose clusters mainly includes CH2, OH, CH, and so on. Glucose hydroxyl radical on the ring is active in the cellulose chain. Where hydroxyl related chemical reaction can occur, Hydroxyl can also be integrated into the intermolecular and intramolecular hydrogen bond. Terahertz wave can promote hydrogen bond vibration. This kind of vibration is weak in the intermolecular interaction. The vibration and rotating happen in dipole transition. The crystal lattice rotates and is absorptive in low frequency, and large molecular skeleton vibrates. All of them can show different intensity and position of the absorption peak in the terahertz band. Corn and cellulose were analyzed by infrared spectrum. The reverse and vibration mode of cellulose was discussed. The absorption peak is basically in line with its theoretical calculating result. It is feasible that Terahertz Time Domain Spectroscopy can detect cellulose, and it provides a new method for the detection and judgement of cellulose in plants.


Asunto(s)
Celulosa/química , Espectrofotometría Infrarroja , Espectroscopía de Terahertz , Enlace de Hidrógeno , Triticum/química , Vibración , Zea mays/química
10.
Sensors (Basel) ; 15(4): 8406-28, 2015 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-25871714

RESUMEN

Underground displacement monitoring is a key means to monitor and evaluate geological disasters and geotechnical projects. There exist few practical instruments able to monitor subsurface horizontal and vertical displacements simultaneously due to monitoring invisibility and complexity. A novel underground displacement 3D measuring sensor had been proposed in our previous studies, and great efforts have been taken in the basic theoretical research of underground displacement sensing and measuring characteristics by virtue of modeling, simulation and experiments. This paper presents an innovative underground displacement joint inversion method by mixing a specific forward modeling approach with an approximate optimization inversion procedure. It can realize a joint inversion of underground horizontal displacement and vertical displacement for the proposed 3D sensor. Comparative studies have been conducted between the measured and inversed parameters of underground horizontal and vertical displacements under a variety of experimental and inverse conditions. The results showed that when experimentally measured horizontal displacements and vertical displacements are both varied within 0~30 mm, horizontal displacement and vertical displacement inversion discrepancies are generally less than 3 mm and 1 mm, respectively, under three kinds of simulated underground displacement monitoring circumstances. This implies that our proposed underground displacement joint inversion method is robust and efficient to predict the measuring values of underground horizontal and vertical displacements for the proposed sensor.

11.
Sensors (Basel) ; 14(5): 9074-92, 2014 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-24858960

RESUMEN

Underground displacement monitoring is an effective method to explore deep into rock and soil masses for execution of subsurface displacement measurements. It is not only an important means of geological hazards prediction and forecasting, but also a forefront, hot and sophisticated subject in current geological disaster monitoring. In previous research, the authors had designed a novel electromagnetic underground horizontal displacement sensor (called the H-type sensor) by combining basic electromagnetic induction principles with modern sensing techniques and established a mutual voltage measurement theoretical model called the Equation-based Equivalent Loop Approach (EELA). Based on that work, this paper presents an underground displacement inversion approach named "EELA forward modeling-approximate inversion method". Combining the EELA forward simulation approach with the approximate optimization inversion theory, it can deduce the underground horizontal displacement through parameter inversion of the H-type sensor. Comprehensive and comparative studies have been conducted between the experimentally measured and theoretically inversed values of horizontal displacement under counterpart conditions. The results show when the measured horizontal displacements are in the 0-100 mm range, the horizontal displacement inversion discrepancy is generally tested to be less than 3 mm under varied tilt angles and initial axial distances conditions, which indicates that our proposed parameter inversion method can predict underground horizontal displacement measurements effectively and robustly for the H-type sensor and the technique is applicable for practical geo-engineering applications.


Asunto(s)
Geología/instrumentación , Magnetismo/instrumentación , Sistemas Microelectromecánicos/instrumentación , Suelo/química , Suelo/clasificación , Transductores , Diseño de Equipo , Análisis de Falla de Equipo
12.
Artículo en Inglés | MEDLINE | ID: mdl-39327815

RESUMEN

DNA in eukaryotic genomes is under constant assault from both exogenous and endogenous sources, leading to DNA damage, which is considered a major molecular driver of ageing. Fortunately, the genome and the central exome are safeguarded against these attacks by abundant peripheral non-coding DNA. Non-coding DNA codes for small non-coding RNAs that inactivate foreign nucleic acids in the cytoplasm and physically blocks these attacks in the nucleus. Damage to non-coding DNA produced during such blockage is removed in the form of extrachromosomal circular DNA (eccDNA) through nucleic pore complexes. Consequently, non-coding DNA serves as a line of defence for the exome against DNA damage. The total amount of non-coding DNA/heterochromatin declines with age, resulting in a decrease in both physical blockage and eccDNA exclusion, and thus an increase in the accumulation of DNA damage in the nucleus during ageing and in age-related diseases. Here, we summarize recent evidence supporting a protective role of non-coding DNA in healthy and pathological states and argue that DNA damage is the proximate cause of ageing and age-related genetic diseases. Strategies aimed at strengthening the protective role of non-coding DNA/heterochromatin could potentially offer better systematic protection for the dynamic genome and the exome against diverse assaults, reduce the burden of DNA damage to the exome, and thus slow ageing, counteract age-related genetic diseases and promote a healthier life for individuals.

13.
Nat Metab ; 6(2): 238-253, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38278946

RESUMEN

Biphasic glucose-stimulated insulin secretion (GSIS) is essential for blood glucose regulation, but a mechanistic model incorporating the recently identified islet ß cell heterogeneity remains elusive. Here, we show that insulin secretion is spatially and dynamically heterogeneous across the islet. Using a zinc-based fluorophore with spinning-disc confocal microscopy, we reveal that approximately 40% of islet cells, which we call readily releasable ß cells (RRßs), are responsible for 80% of insulin exocytosis events. Although glucose up to 18.2 mM fully mobilized RRßs to release insulin synchronously (first phase), even higher glucose concentrations enhanced the sustained secretion from these cells (second phase). Release-incompetent ß cells show similarities to RRßs in glucose-evoked Ca2+ transients but exhibit Ca2+-exocytosis coupling deficiency. A decreased number of RRßs and their altered secretory ability are associated with impaired GSIS progression in ob/ob mice. Our data reveal functional heterogeneity at the level of exocytosis among ß cells and identify RRßs as a subpopulation of ß cells that make a disproportionally large contribution to biphasic GSIS from mouse islets.


Asunto(s)
Insulinas Bifásicas , Células Secretoras de Insulina , Ratones , Animales , Secreción de Insulina , Insulinas Bifásicas/metabolismo , Glucosa/farmacología , Glucosa/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Exocitosis/fisiología
14.
Light Sci Appl ; 12(1): 298, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38097537

RESUMEN

In fluorescence microscopy, computational algorithms have been developed to suppress noise, enhance contrast, and even enable super-resolution (SR). However, the local quality of the images may vary on multiple scales, and these differences can lead to misconceptions. Current mapping methods fail to finely estimate the local quality, challenging to associate the SR scale content. Here, we develop a rolling Fourier ring correlation (rFRC) method to evaluate the reconstruction uncertainties down to SR scale. To visually pinpoint regions with low reliability, a filtered rFRC is combined with a modified resolution-scaled error map (RSM), offering a comprehensive and concise map for further examination. We demonstrate their performances on various SR imaging modalities, and the resulting quantitative maps enable better SR images integrated from different reconstructions. Overall, we expect that our framework can become a routinely used tool for biologists in assessing their image datasets in general and inspire further advances in the rapidly developing field of computational imaging.

15.
Mol Ther ; 19(8): 1478-86, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21540836

RESUMEN

Nonviral vectors present considerable advantages over viral counterparts in gene transfer. However, the poor expression efficiency of the transfected genes poses a challenge for their use in gene therapy, primarily due to the inability of these vectors to overcome various barriers, including the biological barriers. Here, we report that ZNF511-PRAP1 may be involved in the recognition and inactivation of transfected plasmids. ZNF511-PRAP1 is induced by transfection of plasmid DNA and suppresses the transcription of transfected plasmids. It binds directly to the p21 promoter in transfected plasmids but not the endogenous counterpart. Similarly, ZNF511-PRAP1 suppresses the expression of the green fluorescent protein reporter gene on transiently transfected plasmids but not an integrated red fluorescence reporter gene with the same cytomegalovirus (CMV) promoter. Therefore, ZNF511-PRAP1 is able to differentiate between exogenous/nonintegrated and endogenous/integrated DNA. The suppression by ZNF511-PRAP1 is independent of DNA methylation and can be abolished by trichostatin A (TSA) treatment and knockdown of HDAC2 and/or ZNF511-PRAP1. Furthermore, ZNF511-PRAP1 interacts directly with HDAC2. Our results revealed that transfected plasmids are recognized by ZNF511-PRAP1 and suppressed by a repressor complex comprising ZNF511-PRAP1 and HDAC2 and suggest that ZNF511-PRAP1 could play a role as a potential molecular barrier in nonviral transgene expression.


Asunto(s)
Proteínas Portadoras/metabolismo , Expresión Génica , Técnicas de Transferencia de Gen , Plásmidos/genética , Proteínas Gestacionales/metabolismo , Factores de Transcripción/metabolismo , Transgenes/genética , Proteínas Portadoras/genética , Línea Celular Tumoral , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Genes Reporteros , Terapia Genética/métodos , Vectores Genéticos , Histona Desacetilasa 2/genética , Histona Desacetilasa 2/metabolismo , Humanos , Ácidos Hidroxámicos/farmacología , Plásmidos/antagonistas & inhibidores , Plásmidos/metabolismo , Proteínas Gestacionales/genética , Regiones Promotoras Genéticas , ARN Interferente Pequeño/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Factores de Transcripción/efectos de los fármacos , Transfección
17.
Nat Biotechnol ; 40(4): 606-617, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34782739

RESUMEN

A main determinant of the spatial resolution of live-cell super-resolution (SR) microscopes is the maximum photon flux that can be collected. To further increase the effective resolution for a given photon flux, we take advantage of a priori knowledge about the sparsity and continuity of biological structures to develop a deconvolution algorithm that increases the resolution of SR microscopes nearly twofold. Our method, sparse structured illumination microscopy (Sparse-SIM), achieves ~60-nm resolution at a frame rate of up to 564 Hz, allowing it to resolve intricate structures, including small vesicular fusion pores, ring-shaped nuclear pores formed by nucleoporins and relative movements of inner and outer mitochondrial membranes in live cells. Sparse deconvolution can also be used to increase the three-dimensional resolution of spinning-disc confocal-based SIM, even at low signal-to-noise ratios, which allows four-color, three-dimensional live-cell SR imaging at ~90-nm resolution. Overall, sparse deconvolution will be useful to increase the spatiotemporal resolution of live-cell fluorescence microscopy.


Asunto(s)
Algoritmos , Imagenología Tridimensional , Imagenología Tridimensional/métodos , Microscopía Fluorescente/métodos
18.
Zhonghua Gan Zang Bing Za Zhi ; 19(3): 182-5, 2011 Mar.
Artículo en Zh | MEDLINE | ID: mdl-21586235

RESUMEN

OBJECTIVE: HBsAg loss and seroconversion in patients with chronic hepatitis B leads to long-lasting good clinical outcomes. The aim of this paper was to investigate to improve the rate of HBsAg loss and seroconversion in chronic hepatitis B patients by prolonged treatment of PEG-IFNa-2a. 217 cases of HBeAg-positive or negative patients were collected from inpatient and outpatient in Beijing Ditan Hospital from May 2005 to October 2009 and subcutaneous injection of 135 ug or 180 ug PEGASYS were given once a week according to body weights. The drug doses were adjusted according to the neutrophilic granulocyte and platelet counts during treatment course. Quantitative HBV DNA test was conducted using a commercially available real-time fluorescence quantitative PCR kit. The serum HBsAg/anti-HBs and HBeAg/anti-HBe were quantitatively detected by Abbott i 2000 chemiluminescent kit before and during treatment every three months. Patients with HBsAg steadily decreased and reached serum HBsAg level below 200 IU/ml after 48 weeks of treatment would receive prolonged treatment. Patients with more than 12 weeks of treatment entered into analysis. Main efficacy of prolonged treatment was evaluated by the incidences of HBsAg loss and seroconversion. RESULTS: The treatment courses of the 217 patients ranged from 12.0 to 197.6 weeks with an average of 53.1+/-33.4 weeks, 118 cases took more than 48 weeks and another 89 cases less than 48 weeks. 13.4% (29/217) of patients achieved HBsAg loss or HBsAg seroconversion with treatment courses from 17.6 to 197.6 weeks (average 75.4+/-42.8 weeks). Among these 29 patients 24 (82.8%) received more than 48 weeks of treatment, but the treatment courses of HBV DNA reached undetectable level were 20.8+/-8.9 weeks. In this study, 9.5% (14/148) of HBeAg-positive patients achieved HBsAg loss or seroconversion, all of them treated more than 48 weeks, from 48 to 194 weeks, average 81.32+/-39.36 weeks. 21.7% (15/69) of HBeAg-negative patients achieved HBsAg loss or seroconversion, significantly higher than that of HBeAg-positive patients (9.5%) (x2 = 6.129, P = 0.013). The average treatment course for HBeAg-negative patients with HBsAg loss was 70.2+/-48.0 weeks, shorter than that of HBeAg-positive patients with HBsAg loss (81.3+/-39.4 weeks), but no significant difference (t = -0.522, P = 0.602) found between. CONCLUSION: Higher rate of HBsAg loss and seroconversion could be obtained by individual extended treatment courses in patients with rapid HBV DNA and HBsAg response to PEG-IFNa-2a treatment and the HBeAg-negative patients could got higher rate of HBsAg loss than HBeAg-positive patients.


Asunto(s)
Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B Crónica/sangre , Hepatitis B Crónica/tratamiento farmacológico , Interferón-alfa/administración & dosificación , Polietilenglicoles/administración & dosificación , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Antígenos de Superficie de la Hepatitis B/inmunología , Virus de la Hepatitis B , Hepatitis B Crónica/inmunología , Humanos , Lactante , Interferón-alfa/uso terapéutico , Masculino , Persona de Mediana Edad , Polietilenglicoles/uso terapéutico , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/uso terapéutico , Resultado del Tratamiento , Adulto Joven
19.
Ageing Res Rev ; 67: 101306, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33610814

RESUMEN

Extrachromosomal circular DNA (eccDNA) accumulates within the nucleus of eukaryotic cells during physiological aging and in age-related diseases (ARDs) and the accumulation could be caused by the declined exclusion of nuclear eccDNA in these states. This review focuses on the formation of eccDNA and the roles of some main factors, such as nuclear pore complexes (NPCs), nucleoplasmic reticulum (NR), and nuclear actin, in eccDNA exclusion. eccDNAs are mostly formed from non-coding DNA during DNA damage repair. They move to NPCs along nuclear actin and are excluded out of the nucleus through functional NPCs in young and healthy cells. However, it has been demonstrated that defective NPCs, abnormal NPC components and nuclear actin rods are increased in aged cells, various cancers and certain other ARDs such as cardiovascular diseases, premature aging, neurodegenerative diseases and myopathies. Therefore, mainly resulting from the increase of dysfunctional NPCs, the exclusion of nuclear eccDNAs may be reduced and eccDNAs thus accumulate within the nucleus in aging and the aforementioned ARDs. In addition, the protective function of non-coding DNA in tumorigenesis is further discussed.


Asunto(s)
ADN Circular , ADN , Anciano , Envejecimiento/genética , Núcleo Celular , Humanos
20.
Zhonghua Gan Zang Bing Za Zhi ; 17(7): 497-500, 2009 Jul.
Artículo en Zh | MEDLINE | ID: mdl-19912682

RESUMEN

OBJECTIVE: To evaluate whether the rapid viral response (RVR) to combinational therapy with interferon and rabavirin can be used to predict the sustained viral response (SVR) in chronic hepatitis C patients. METHODS: According to their clinical characteristics, all patients in this study were given pegylated or conventional interferon injection and different dose of ribavirin according to their weight. Patients were injected Pegasys (pegierferon alpha-2a) 180 microg or 135 microg once a week, or pegyintron 50-80 microg once a week, or conventional interferon 3-5 MU every two days, in combination with a dose of 600-1500 mg/d ribavirin. The serum HCV RNA load was determined at 0, 4, 12 week, and then every 12 weeks. After the viral response obtained, the patients were treated for another 24-72 weeks and followed up 24 weeks. The main parameter to evaluate the efficacy was SVR rate. The influence factors associated with rapid viral response were investigated. RESULTS: RVR was obtained at week 4 in 84.2% of the 120 patients. The HCV RNA baseline of RVR group was (5.883+/-1.246) lg copies/ml, which was significantly lower than that of the group without RVR [(6.502+/-0.693) lg copies/ml, t=2.15, P=0.034]. 97 patients with RVR who finished treatment and follow-up, 90.7% of these patients obtained SVR, but the SVR rate in patients (82.4%) without RVR was lower than that in patients with RVR (x2=0.371, P=0.543). In this study, RVR rate was not associated with HCV genotype and the dose of interferon used. In the naive patients, the RVR to pegylated interferon was 87.8%, which was significantly higher than that in retreat patients (x2=4.651, P=0.031). CONCLUSION: High RVR rate could be obtained in chronic hepatitis C patients treated combined with interferon and ribavirin. RVR rate is associated with the HCV RNA baseline load in both naive and retreat patients but not correlated to HCV genotype. RVR could predict the SVR.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Ribavirina/uso terapéutico , Administración Cutánea , Adolescente , Adulto , Anciano , Antivirales/administración & dosificación , Niño , Quimioterapia Combinada , Femenino , Genotipo , Hepacivirus/efectos de los fármacos , Hepacivirus/genética , Hepatitis C Crónica/sangre , Hepatitis C Crónica/patología , Humanos , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Masculino , Persona de Mediana Edad , Polietilenglicoles/administración & dosificación , Valor Predictivo de las Pruebas , ARN Viral/sangre , Proteínas Recombinantes , Recurrencia , Ribavirina/administración & dosificación , Factores de Tiempo , Resultado del Tratamiento , Carga Viral , Adulto Joven
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