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1.
Am J Hypertens ; 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38606768

RESUMEN

BACKGROUND: We aimed to investigate the association between hemoglobin A1c (HbA1c) and left atrial (LA) stiffness in patients with hypertension and to explore the mediating effect of the neutrophil/lymphocyte ratio (NLR) on this association. METHODS: Essential hypertensive patients (n=292) aged 18 to 83 years were enrolled and divided into two groups based on the LA stiffness index (LASI): Group I (LASI≤0.32, n=146) and Group II (LASI>0.32, n=146). The LASI was defined as the ratio of early diastolic transmitral flow velocity/lateral mitral annulus myocardial velocity (E/e') to LA reservoir strain. Multivariate linear regression analysis was performed to determine the independent predictors of the LASI. RESULTS: Age, BMI, SBP, HbA1c, CRP and the NLR were significantly greater in Group II than in Group I (P<0.05). Additionally, Group II had a greater LA volume index (LAVI), left ventricular mass index (LVMI), and E/e' and lower LA reservoir, conduit and booster pump strains than Group I (P<0.001). Univariate and multivariate linear regression models revealed that age, SBP, HbA1c, and the NLR were independently associated with the LASI. Further mediation analysis was performed to determine the mediating effect of the NLR on the association between HbA1c and the LASI and revealed that the NLR had a mediating role only in overweight hypertensive patients, and the proportion of the mediating effect was 21.9%. CONCLUSIONS: The NLR was independently correlated with the LASI and played a mediating role in the relationship between HbA1c and the LASI in overweight hypertensive patients.

2.
Phys Rev Lett ; 131(2): 025101, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37505952

RESUMEN

A novel compact high-flux neutron generator with a pitcher-catcher configuration based on laser-driven collisionless shock acceleration (CSA) is proposed and experimentally verified. Different from those that previously relied on target normal sheath acceleration (TNSA), CSA in nature favors not only acceleration of deuterons (instead of hydrogen contaminants) but also increasing of the number of deuterons in the high-energy range, therefore having great advantages for production of high-flux neutron source. The proof-of-principle experiment has observed a typical CSA plateau feature from 2 to 6 MeV in deuteron energy spectrum and measured a forward neutron flux with yield 6.6×10^{7} n/sr from the LiF catcher target, an order of magnitude higher than the compared TNSA case, where the laser intensity is 10^{19} W/cm^{2}. Self-consistent simulations have reproduced the experimental results and predicted that a high-flux forward neutron source with yield up to 5×10^{10} n/sr can be obtained when laser intensity increases to 10^{21} W/cm^{2} under the same laser energy.

3.
Zhonghua Yi Xue Za Zhi ; 102(32): 2538-2540, 2022 Aug 30.
Artículo en Chino | MEDLINE | ID: mdl-36008325

RESUMEN

This study aimed to build a home use deep learning segmentation model to identify the scope of caries lesions. A total of 494 caries photographs of molars and premolars collected via endoscopy were selected. Subsequently, these photographs were labeled by physicians and underwent segmentation training by using DeepLabv3+, and then verification and evaluation were performed. The mean accuracy was 0.993, the sensitivity was 0.661, the specificity was 0.997, the Dice coefficient was 0.685, and the intersection over union (IoU) was 0.529. Therefore, the present deep learning segmentation model can identify and segment the scope of caries.


Asunto(s)
Aprendizaje Profundo , Diente Premolar , Susceptibilidad a Caries Dentarias , Diente Molar/patología
4.
Phys Rev E ; 105(2): L023202, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35291060

RESUMEN

In one-dimensional particle-in-cell simulations of a plasma irradiated by linearly polarized lasers from both sides of boundaries, it is found that there is an appreciable growth of the electromagnetic field in cavitons in the transverse direction perpendicular to the direction of polarization, which indicates the polarization conversion of the electromagnetic field in cavitons. This paper demonstrates the mechanism of this phenomenon based on parametric resonance induced by ponderomotive force with twice the frequency of the electromagnetic radiation in the caviton. We develop a theoretical model and verify it with simulation results. This phenomenon contributes to the heating and acceleration of particles and traps more EM energy in cavitons.

5.
Phys Rev E ; 104(2-2): 025204, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34525564

RESUMEN

Inverse magnetic energy transfer from small to large scales is a key physical process for the origin of large-scale strong magnetic fields in the universe. However, so far, from the magnetohydrodynamic perspective, the onset of inverse transfer is still not fully understood, especially the underlying dynamics. Here, we use both two-dimensional and three-dimensional particle-in-cell simulations to show the self-consistent dynamics of inverse transfer in collisionless decaying turbulent plasmas. Using the space filtering technique in theory and numerical analyses, we identify magnetic reconnection as the onset and fundamental drive for inverse transfer, where, specifically, the subscale electromotive force driven by magnetic reconnection do work on the large-scale magnetic field, resulting in energy transfer from small to large scales. The mechanism is also verified by the strong correlations in locations and characteristic scales between inverse transfer and magnetic reconnection.

6.
Phys Rev E ; 104(2-2): 025210, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34525575

RESUMEN

Laser-driven ion acceleration has attracted global interest for its potential towards the development of a new generation of compact, low-cost accelerators. Remarkable advances have been seen in recent years with a substantial proton energy increase in experiments, when nanometer-scale ultrathin foil targets and high-contrast intense lasers are applied. However, the exact acceleration dynamics and particularly the ion energy scaling laws in this novel regime are complex and still unclear. Here, we derive a scaling law for the attainable maximum ion energy from such laser-irradiated nanometer-scale foils based on analytical theory and multidimensional particle-in-cell simulations, and further show that this scaling law can be used to accurately describe experimental data over a large range of laser and target parameters on different facilities. This provides crucial references for parameter design and experimentation of the future laser devices towards various potential applications.

7.
Eur Rev Med Pharmacol Sci ; 24(15): 7913, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32767356

RESUMEN

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "Long non-coding RNA OR3A4 promotes metastasis of ovarian cancer via inhibiting KLF6, by F.-F. Guo, M.-M. Jiang, L.-L. Hong, B. Qiao, X.-M. Lin, W.-Y. Xu, X.-Q. Fu, published in Eur Rev Med Pharmacol Sci 2019; 23 (6): 2360-2365-DOI: 10.26355/eurrev_201903_17380-PMID: 30964160" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/17380.

8.
Phys Rev Lett ; 124(11): 114802, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-32242678

RESUMEN

A new regime in the interaction of a two-color (ω,2ω) laser with a nanometer-scale foil is identified, resulting in the emission of extremely intense, isolated attosecond pulses-even in the case of multicycle lasers. For foils irradiated by lasers exceeding the blow-out field strength (i.e., capable of fully separating electrons from the ion background), the addition of a second harmonic field results in the stabilization of the foil up to the blow-out intensity. This is then followed by a sharp transition to transparency that essentially occurs in a single optical cycle. During the transition cycle, a dense, nanometer-scale electron bunch is accelerated to relativistic velocities and emits a single, strong attosecond pulse with a peak intensity approaching that of the laser field.

9.
Eur Rev Med Pharmacol Sci ; 23(6): 2360-2365, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30964160

RESUMEN

OBJECTIVE: Recently, long noncoding RNAs (lncRNAs) have attracted much attention for their roles in tumor progression. The aim of this study was to investigate the exact role of lncRNA OR3A4 in the development of ovarian cancer (OC), and to explore the possible underlying mechanism. PATIENTS AND METHODS: OR3A4 expression in OC tissue samples was detected by Real-time quantitative polymerase chain reaction (qRT-PCR). Moreover, wound healing assay and transwell assay were performed to evaluate the effect of OR3A4 on the metastasis of OC. Furthermore, the underlying mechanism was explored by RT-qPCR and Western blot assay. RESULTS: The expression level of OR3A4 in OC samples was significantly higher than that of adjacent tissues. Moreover, cell migration and invasion were significantly repressed after OR3A4 knockdown in vitro. Moreover, the mRNA and protein expressions of kruppel-like factor 6 (KLF6) were remarkably upregulated after knockdown of OR3A4. Furthermore, the expression level of KLF6 was negatively correlated with the expression of OR3A4 in OC tissues. CONCLUSIONS: Our results showed that OR3A4 could enhance OC cell metastasis and invasion via suppressing KLF6. Moreover, OR3A4 might be a potential therapeutic target for OC.

10.
Sci Rep ; 8(1): 17538, 2018 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-30510273

RESUMEN

Intense lasers can accelerate protons in sufficient numbers and energy that the resulting beam can heat materials to exotic warm (10 s of eV temperature) states. Here we show with experimental data that a laser-driven proton beam focused onto a target heated it in a localized spot with size strongly dependent upon material and as small as 35 µm radius. Simulations indicate that cold stopping power values cannot model the intense proton beam transport in solid targets well enough to match the large differences observed. In the experiment a 74 J, 670 fs laser drove a focusing proton beam that transported through different thicknesses of solid Mylar, Al, Cu or Au, eventually heating a rear, thin, Au witness layer. The XUV emission seen from the rear of the Au indicated a clear dependence of proton beam transport upon atomic number, Z, of the transport layer: a larger and brighter emission spot was measured after proton transport through the lower Z foils even with equal mass density for supposed equivalent proton stopping range. Beam transport dynamics pertaining to the observed heated spot were investigated numerically with a particle-in-cell (PIC) code. In simulations protons moving through an Al transport layer result in higher Au temperature responsible for higher Au radiant emittance compared to a Cu transport case. The inferred finding that proton stopping varies with temperature in different materials, considerably changing the beam heating profile, can guide applications seeking to controllably heat targets with intense proton beams.

11.
Eur Rev Med Pharmacol Sci ; 22(16): 5305-5311, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30178855

RESUMEN

OBJECTIVE: Although direct-acting antiviral agents (DAAs) for treating hepatitis C virus (HCV) infection have not yet been approved for clinical application at present in China, the development trend is irresistible. DAAs-containing therapeutic regimens have been approved and others are also under development worldwide. In vitro studies have shown that S282T mutation in the NS5B region of HCV is involved in DAAs resistance. The aim of this study was to investigate naturally occurring resistance mutation of S282T in different genotypes of HCV from DAA-treated naïve Chinese patients who were chronically infected with HCV. PATIENTS AND METHODS: 250 Chinese patients chronically infected with HCV were enrolled in this study. All subjects were naïve to DAAs. Direct sequencing of HCV NS5B region was performed in all enrolled patients. RESULTS: 70.4% (176/250) cases were infected with HCV genotype 1b, 19.2% (47/250) were 2a, 4.0% (11/250) were 6a, 3.6% (10/250) were 3b, 1.6% (4/250) were 1a and 1.2% (3/250) were 3a. Genotype 4, 5 and 7 were not observed. The S282T mutation was not found in any of the cases. CONCLUSIONS: The results showed that the S282T mutation was not prevalent in DAA-treated naïve Chinese patients who were chronically infected with HCV.


Asunto(s)
Antivirales/uso terapéutico , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Adulto , China , Farmacorresistencia Viral , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Mutación , Prevalencia
12.
Zhonghua Wai Ke Za Zhi ; 56(3): 196-200, 2018 Mar 01.
Artículo en Chino | MEDLINE | ID: mdl-29534413

RESUMEN

Objective: To discuss the clinical outcomes of treating delayed acetabular fractures by combined anterior and posterior approach. Methods: A retrospective analysis was conducted of 31 delayed acetabular fractures from February 2012 to February 2017 in the First Affiliated Hospital of Chongqing Medical University, including 18 males and 13 females with age of 48.5 years(23 to 67 years) .The injury to the operation time was 35.9 days(22 to 183 days). Of these 31 cases, there were 6 cases of transverse and posterior wall fracture, 8 cases with anterior column+ posterior half transverse fracture, 12 cases with double column fracture and 5 cases of "T" type fracture according to Letournel-Judet classification.All fractures were treated combined anterior and Kocher-Langenbeck approaches, including 13 cases of ilioinguinal approach+ Kocher-Langenbeck(K-L approach), 4 cases of extensile acetabular approach, 7 cases of stoppa approach + K-L approach and 7 cases of side rectus femoris approach.Correlation was analyzed by Pearson correlation regression testing. Results: Follow up to August 2017, all patients were followed up with 36.0 months(from 6 to 55 months). As calculated, the restorational effect was positively with result of the X-ray film and the clinical effect(r=0.823, 0.856; both P<0.05). The evaluation was conducted with Matta's reduction criteria: there were 11 cases classified as anatomic reduction(35.5%), 13 cases as satisfactory reduction(41.9%), and 7 cases as unsatisfactory reduction(22.6%). Excellent and good rate was 77.4%. Functional reductions were categorized by the standard of Matta hip score: 8 excellent cases(25.8%), 11 good cases(35.5%), 8 fail cases(25.8%), and 4 poor cases(12.9%). Conclusion: The treatment of delayed acetabular fracture by combined anterior and posterior approach can fully exposure the anterior and posterior acetabular fcloumns, which is beneficial to the release and fixation of the old acetabular fractures.


Asunto(s)
Acetábulo , Fijación Interna de Fracturas , Fracturas Óseas , Fracturas de Cadera , Acetábulo/lesiones , Acetábulo/cirugía , Adulto , Anciano , Femenino , Fracturas Óseas/cirugía , Fracturas de Cadera/cirugía , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Fracturas de la Columna Vertebral , Resultado del Tratamiento , Adulto Joven
13.
Acta Endocrinol (Buchar) ; 14(2): 155-162, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-31149252

RESUMEN

BACKGROUND: This study aimed to assess the mechanism through which Wnt/ beta - catenin signaling pathway, and StarD7, prometes testosterone synthesis, and to explore a new pathway for the regulation of testosterone synthesis. ANIMALS AND METHODS: Leydig cells were isolated from male Sprague-Dawley rats divided into four groups and treated with Annexin 5 in concentration of 0, 0.1, 1 and 10 nmol/L. Testosterone secretion, expression of StarD7, StarD7 mRNA, ß-catenin and changes of ß - catenin localization in Leydig cells of testis of rats were tested in the four groups. RESULTS: mRNA and protein levels of StarD7 and ß-catenin increased significantly, upon stimulation with 1 nmol/L annexin 5. Accumulation of ß-catenin inside the cells and the nucleus, was observed by immunofluorescence staining, in cells treated with annexin 5. These findings indicate a possible role of StarD7 and ß-catenin in the process of annexin5-mediated stimulation of testosterone synthesis. CONCLUSIONS: Wnt/ß-catenin signaling pathway and StarD7 are involved in the process of annexin5 stimulation of testosterone synthesis. Activation of Wnt/ ß-catenin signaling pathway by Annexin5, and increase in StarD7 expression lead to elevated expression of key regulatory enzymes in testosterone synthesis, thus promoting testosterone synthesis.

14.
Zhonghua Yi Xue Za Zhi ; 97(43): 3388-3391, 2017 Nov 21.
Artículo en Chino | MEDLINE | ID: mdl-29179278

RESUMEN

Objective: To investigate the relationship between the expression of macrophage migration inhibitory factor (MIF) gene and the incidence of gestational diabetes mellitus (GDM) in Chinese Han population in northern China. Method: This study was consisted of 126 GDM women and 150 cases of healthy subjects who came from the obstetrics department of Maternity Hospital of Qingdao University and Maternity and Child Care Hospital of Donggang District of Rizhao. The protein expression of MIF in placenta tissue was detected by Western blot method. The blood glucose, insulin levels and other clinical physicochemical index were tested. The differences of MIF, fasting blood-glucose (FBG), fasting insulin (FIN) and the homeostasis model assessment of insulin resistance (HOMA-IR) were compared between the two groups of pregnant women. Result: The level of MIF protein in GDM group (0.85±0.10) was higher than that in healthy pregnant group (0.12±0.09), with significant difference (P<0.001). Insulin resistance index in GDM group were higher than that in healthy pregnant group, with significant difference (P<0.001). Conclusion: The expression of MIF in placental tissues of GDM women was increased and correlated with insulin resistance in GDM patients, suggesting that MIF may play an important role in the occurrence and development of GDM.


Asunto(s)
Diabetes Gestacional/genética , Oxidorreductasas Intramoleculares/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Placenta/metabolismo , Glucemia , China , Femenino , Humanos , Insulina , Resistencia a la Insulina , Embarazo
15.
Phys Rev E ; 95(5-1): 053205, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28618622

RESUMEN

It was shown that in the interactions of ultra-intense circularly polarized laser pulse with the near-critical plasmas, the angular momentum can be transferred efficiently from the laser beam to electrons through the resonance acceleration process. The transferred angular momentum increases almost linearly with the acceleration time t_{a} when the electrons are resonantly accelerated by the laser field. In addition, it is shown analytically that the averaged angular momentum of electrons is proportional to the laser amplitude a_{L}, and the total angular momentum of the accelerated electron beam is proportional to the square of the laser amplitude a_{L}^{2} for a fixed parameter of n_{e}/n_{c}a_{L}. These results are verified by three-dimensional particle-in-cell simulations. This regime provides an efficient and compact alternative for the production of high angular momentum electron beams, which may have many potential applications in condensed-matter spectroscopy, new electron microscopes, and bright x-ray vortex generation.

16.
Phys Rev Lett ; 118(20): 204802, 2017 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-28581776

RESUMEN

A method to achieve stable radiation pressure acceleration (RPA) of heavy ions from laser-irradiated ultrathin foils is proposed, where a high-Z material coating in front is used. The coated high-Z material, acting as a moving electron repository, continuously replenishes the accelerating heavy ion foil with comoving electrons in the light-sail acceleration stage due to its successive ionization under laser fields with Gaussian temporal profile. As a result, the detrimental effects such as foil deformation and electron loss induced by the Rayleigh-Taylor-like and other instabilities in RPA are significantly offset and suppressed so that stable acceleration of heavy ions are maintained. Particle-in-cell simulations show that a monoenergetic Al^{13+} beam with peak energy 3.8 GeV and particle number 10^{10} (charge >20 nC) can be obtained at intensity 10^{22} W/cm^{2}.

17.
Phys Rev E ; 95(4-1): 043207, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28505773

RESUMEN

The hosing processes of a relativistic laser pulse, electron acceleration, and betatron radiation in a parabolic plasma channel are investigated in the direct laser acceleration regime. It is shown that the laser hosing instability would result in the generation of a randomly directed off-axis electron beam and radiation source with a large divergence angle. While employing a preformed parabolic plasma channel, the restoring force provided by the plasma channel would correct the perturbed laser wave front and thus suppress the hosing instability. As a result, the accelerated electron beam and the emitted photons are well guided and concentrated along the channel axis. The employment of a proper plasma density channel can stably guide the relativistically intense laser pulse and greatly improve the properties of the electron beam and radiation source. This scheme is of great interest for the generation of high quality electron beams and radiation sources.

18.
Clin. transl. oncol. (Print) ; 19(5): 562-570, mayo 2017. graf
Artículo en Inglés | IBECS | ID: ibc-162189

RESUMEN

Objective. Recent studies have identified Engrailed-2 (EN-2), a homeobox-containing transcription factor, as a candidate oncogene in prostate cancer (PC). Therapeutic targeting on EN-2, however, is limited because the mechanism underlying EN-2 overexpression in prostatic cancer cells is unknown. This study was to investigate the potential regulatory role of miR-33a on EN-2 expression and explore this signaling axis in ability of prostate cancer survival and metastasis. Methods. The relative expression of miR-33a and EN-2 in paired prostate cancer tissue and adjacent normal tissue as well as in prostate cancer cell lines, PC3 and DU145, was determined using quantitative real-time PCR or western blot, respectively. Cells survival, migration and invasion were evaluated by assays of MTT, TUNEL and Boyden chamber assays, respectively. Direct regulation of EN-2 by miR-33a was examined by luciferase reporter assay. Results. The data showed that miR-33a was upregulated and EN-2 was downregulated in both prostate cancer tissue and prostate cancer cells. miR-33a overexpression suppresses prostate cancer cell survival and metastasis. miR-33a can directly act on EN-2 expression by binding to 3′UTR of its mRNA. Also, miR-33a negatively regulated EN-2 mRNA and protein expression. In pcDNA-EN-2 and miR-33a mimic co-transfected PC3 and DU145 cells, EN-2 overexpression reverses the anti-cell survival and metastasis actions of miR-33a overexpression. The pivotal role of miR-33a in inhibiting prostate tumor growth was confirmed in xenograft models of prostate cancer. Conclusion. Our data suggest that the functional interaction of miR-33a and EN-2 is involved in tumorigenesis of prostate cancer. Also in this process EN-2 serves as a negative responder for miR-33a (AU)


No disponible


Asunto(s)
Humanos , Masculino , Neoplasias de la Próstata/complicaciones , Neoplasias de la Próstata/patología , Metástasis de la Neoplasia/fisiopatología , ARN Mensajero/genética , Proteína de Susceptibilidad a Apoptosis Celular/genética , Movimiento Celular/genética , Biomarcadores de Tumor/genética , Neoplasias de la Próstata/genética , Reacción en Cadena de la Polimerasa/tendencias , ARN Mensajero/metabolismo , Western Blotting , Luciferasas/análisis , Análisis de Varianza , Represión Epigenética/genética , Proto-Oncogenes/genética , Proteínas Oncogénicas/genética
19.
Sci Rep ; 7: 45031, 2017 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-28338010

RESUMEN

We show a new resonance acceleration scheme for generating ultradense relativistic electron bunches in helical motions and hence emitting brilliant vortical γ-ray pulses in the quantum electrodynamic (QED) regime of circularly-polarized (CP) laser-plasma interactions. Here the combined effects of the radiation reaction recoil force and the self-generated magnetic fields result in not only trapping of a great amount of electrons in laser-produced plasma channel, but also significant broadening of the resonance bandwidth between laser frequency and that of electron betatron oscillation in the channel, which eventually leads to formation of the ultradense electron bunch under resonant helical motion in CP laser fields. Three-dimensional PIC simulations show that a brilliant γ-ray pulse with unprecedented power of 6.7 PW and peak brightness of 1025 photons/s/mm2/mrad2/0.1% BW (at 15 MeV) is emitted at laser intensity of 1.9 × 1023 W/cm2.

20.
Phys Rev E ; 95(1-1): 013210, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28208321

RESUMEN

γ-ray flash generation in near-critical-density target irradiated by four symmetrical colliding laser pulses is numerically investigated. With peak intensities about 10^{23} W/cm^{2}, the laser pulses boost electron energy through direct laser acceleration, while pushing them inward with the ponderomotive force. After backscattering with counterpropagating laser, the accelerated electron is trapped in the electromagnetic standing waves or the ponderomotive potential well created by the coherent overlapping of the laser pulses, and emits γ-ray photons in a multiple-laser-scattering regime, where electrons act as a medium transferring energy from the laser to γ rays in the ponderomotive potential valley.

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