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1.
Plant Mol Biol ; 114(2): 20, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38363403

RESUMEN

SQUAMOSA PROMOTER BINDING PROTEIN-LIKEs (SPLs) encode plant-specific transcription factors that regulate plant growth and development, stress response, and metabolite accumulation. However, there is limited information on Scutellaria baicalensis SPLs. In this study, 14 SbSPLs were identified and divided into 8 groups based on phylogenetic relationships. SbSPLs in the same group had similar structures. Abscisic acid-responsive (ABRE) and MYB binding site (MBS) cis-acting elements were found in the promoters of 8 and 6 SbSPLs. Segmental duplications and transposable duplications were the main causes of SbSPL expansion. Expression analysis based on transcriptional profiling showed that SbSPL1, SbSPL10, and SbSPL13 were highly expressed in roots, stems, and flowers, respectively. Expression analysis based on quantitative real-time polymerase chain reaction (RT‒qPCR) showed that most SbSPLs responded to low temperature, drought, abscisic acid (ABA) and salicylic acid (SA), among which the expression levels of SbSPL7/9/10/12 were significantly upregulated in response to abiotic stress. These results indicate that SbSPLs are involved in the growth, development and stress response of S. baicalensis. In addition, 8 Sba-miR156/157 s were identified, and SbSPL1-5 was a potential target of Sba-miR156/157 s. The results of target gene prediction and coexpression analysis together indicated that SbSPLs may be involved in the regulation of L-phenylalanine (L-Phe), lignin and jasmonic acid (JA) biosynthesis. In summary, the identification and characterization of the SbSPL gene family lays the foundation for functional research and provides a reference for improved breeding of S. baicalensis stress resistance and quality traits.


Asunto(s)
Ácido Abscísico , Scutellaria baicalensis , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Scutellaria baicalensis/genética , Scutellaria baicalensis/metabolismo , Filogenia , Fitomejoramiento , Estrés Fisiológico/genética , Hormonas/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/metabolismo
2.
Am J Hum Genet ; 108(7): 1350-1355, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34115965

RESUMEN

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), a respiratory illness that can result in hospitalization or death. We used exome sequence data to investigate associations between rare genetic variants and seven COVID-19 outcomes in 586,157 individuals, including 20,952 with COVID-19. After accounting for multiple testing, we did not identify any clear associations with rare variants either exome wide or when specifically focusing on (1) 13 interferon pathway genes in which rare deleterious variants have been reported in individuals with severe COVID-19, (2) 281 genes located in susceptibility loci identified by the COVID-19 Host Genetics Initiative, or (3) 32 additional genes of immunologic relevance and/or therapeutic potential. Our analyses indicate there are no significant associations with rare protein-coding variants with detectable effect sizes at our current sample sizes. Analyses will be updated as additional data become available, and results are publicly available through the Regeneron Genetics Center COVID-19 Results Browser.


Asunto(s)
COVID-19/diagnóstico , COVID-19/genética , Secuenciación del Exoma , Exoma/genética , Predisposición Genética a la Enfermedad , Hospitalización/estadística & datos numéricos , COVID-19/inmunología , COVID-19/terapia , Femenino , Humanos , Interferones/genética , Masculino , Pronóstico , SARS-CoV-2 , Tamaño de la Muestra
3.
Ann Surg Oncol ; 31(5): 3212-3221, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38349564

RESUMEN

BACKGROUND: Traditionally, surgical treatment is recommended for right-sided colonic cancer obstruction (RCCO); however, the literature comparing surgical or non-surgical procedures is lacking. METHODS: Patients included in this study were divided into two groups: one group received elective surgery after self-expanding metal stent (SEMS) placement, i.e., the bridge to surgery (BTS) group, and one group received emergency surgery (ES). RESULTS: Thirty-five patients were included in the BTS group and 60 patients underwent ES. The technical and clinical success rates for SEMS placement were 100% and 88.6%, respectively, while the short-term complication rates were 51.4% and 33.3% for the BTS and ES groups, respectively (p = 0.082). Overall, 2.9% and 3.3% of postoperative deaths occurred in the BTS and ES groups (p = 1.000). The 1-year overall survival (OS) rates were 91.4% and 88.3% (p = 0.840), 3-year OS rates were 85.7% and 81.7% (p = 0.860), and 5-year OS rates were 82.9% and 76.7% (p = 0.620) in the BTS and ES groups, respectively. No tumor recurrence was found in the BTS group but seven recurrences were found in the ES group (11.7%) [p = 0.091]. Laparoscopic surgery was chosen by 42.9% of patients in the BTS group and 26.7% of patients in the ES group (p = 0.104); however, the length of hospital stay (p = 0.001) was longer in the BTS group. CONCLUSIONS: In the two groups, no differences were found in terms of postoperative complications and mortality as well as OS. The BTS group preferred to perform laparoscopic surgery and the technical success rate of stenting was high, therefore SEMS for RCCO was considered safe and feasible.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Obstrucción Intestinal , Stents Metálicos Autoexpandibles , Humanos , Neoplasias Colorrectales/patología , Stents Metálicos Autoexpandibles/efectos adversos , Recurrencia Local de Neoplasia/complicaciones , Neoplasias del Colon/complicaciones , Neoplasias del Colon/cirugía , Stents/efectos adversos , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Resultado del Tratamiento , Estudios Retrospectivos
4.
Opt Express ; 32(3): 2906-2915, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38297527

RESUMEN

We present a novel micro-fabrication technique for creating concave surfaces on the endfacets of photonic crystal fibers. A fiber fusion splicer is used to generate arc discharges to melt and reshape the fiber endfacet. This technique can produce large spherical concave surfaces with roughness as low as 0.12 nm in various types of photonic crystal fibers. The deviation of fabricated surface and a spherical profile in the region of 70 µm in diameter is less than 50 nm. The center of the concave surface and the fiber mode field are highly coincident with a deviation less than 500 nm. Finesse measurements have shown that a Fabry-Pérot cavity composed of the fiber fabricated using this method and a plane mirror maintains finesse of 20000. This method is easy to replicate, making it a practical and efficient approach to fabricate concave surface on fibers for open-access fiber Fabry-Pérot cavities.

5.
Phys Rev Lett ; 132(16): 160201, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38701466

RESUMEN

Quantum theory allows information to flow through a single device in a coherent superposition of two opposite directions, resulting into situations where the input-output direction is indefinite. Here we introduce a theoretical method to witness input-output indefiniteness in a single quantum device, and we experimentally demonstrate it by constructing a photonic setup that exhibits input-output indefiniteness with a statistical significance exceeding 69 standard deviations. Our results provide a way to characterize input-output indefiniteness as a resource for quantum information and photonic quantum technologies and enable tabletop simulations of hypothetical scenarios exhibiting quantum indefiniteness in the direction of time.

6.
Genet Epidemiol ; 46(3-4): 199-212, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35170807

RESUMEN

Coronary artery disease (CAD) is a preeminent cause of death, and smoking is a strong risk factor for CAD. Genetic factors contribute to the development of CAD, but the interplay between genetic predisposition and smoking history in CAD remains unclear. Using data from the UK Biobank, we constructed several genetic risk scores (GRSs) based on known CAD loci and assessed their interactions with smoking for the development of incident CAD in 307,147 participants of European ancestry who were free of CAD. We fitted Cox proportional hazard models and assessed gene-smoking interaction on both multiplicative and additive scales. Overall, we found no multiplicative interactions, but observed a synergistic additive interaction of GRS with both smoking status and pack-years of smoking, finding that the absolute CAD risk due to smoking was higher for those with high genetic risk. Trait-based sub-GRSs suggested smoking status and smoking intensity measured by pack-years might confer gene-smoking interaction effects with different intermediate risk factors for CAD. Our study results suggest that genetics could modify the effects of smoking on CAD and highlight the value of addressing gene-lifestyle interactions on both additive and multiplicative scales.


Asunto(s)
Enfermedad de la Arteria Coronaria , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/genética , Predisposición Genética a la Enfermedad , Humanos , Modelos Genéticos , Factores de Riesgo , Fumar/efectos adversos , Fumar/genética
7.
Phys Rev Lett ; 130(15): 150801, 2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37115884

RESUMEN

Recently, a proper genuine multipartite entanglement measure has been found for three-qubit pure states [see Xie and Eberly, Phys. Rev. Lett. 127, 040403 (2021)PRLTAO0031-900710.1103/PhysRevLett.127.040403], but capturing useful entanglement measures for mixed states has remained an open challenge. So far, it requires not only a full tomography in experiments, but also huge calculational labor. A leading proposal was made by Gühne, Reimpell, and Werner [Phys. Rev. Lett. 98, 110502 (2007)PRLTAO0031-900710.1103/PhysRevLett.98.110502], who used expectation values of entanglement witnesses to describe a lower bound estimation of entanglement. We provide here an extension that also gives genuine upper bounds of entanglement. This advance requires only the expectation value of any Hermitian operator. Moreover, we identify a class of operators A_{1} that not only give good estimates, but also require a remarkably small number of experimental measurements. In this Letter, we define our approach and illustrate it by estimating entanglement measures for a number of pure and mixed states prepared in our recent experiments.

8.
BMC Endocr Disord ; 23(1): 272, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38057786

RESUMEN

OBJECTIVES: Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by chronic hyperglycemia and metabolic stress, involved in the stepwise development of cardiovascular complications. Fibroblast growth factor 21 (FGF21) is a novel hepatokine involved in regulating glucose and lipid metabolism, and has been linked to the prediction, treatment, and improvement of prognosis in multiple cardiovascular diseases (CVDs). The aim of this study is to explore the relationship between FGF21 levels and vascular diseases (VDs) including carotid atherosclerosis (CAS) and hypertension (HP) in patients with T2DM. METHODS: Baseline serum FGF21 was determined in a cross-sectional study of 701 patients with T2DM and 258 healthy control. RESULTS: The morbidity of CAS was increased in T2DM patients with HP as compared with those without (p < 0.001). The average serum FGF21 level of healthy was [123.9 (67.2-219.3)]. Baseline FGF21 was significantly higher in those who developed CAS or HP than in those who did not [305.9 (177.2-508.4) vs. 197.2 (129.7-308.3) pg/mL, p < 0.001]. In addition, an elevated serum FGF21 was observed in T2DM patients with HP and CAS than that of T2DM patients with CAS or HP [550.5 (312.6-711.3) vs. 305.9 pg/mL, p < 0.001]. Serum FGF21 levels were positively correlated with body mass index and carotid intima media thicknes (p < 0.05), the association remained significant after adjusting for age and T2DM duration. Furthermore, the multinomial logistic regression showed that serum FGF21 was independently associated with CAS and HP in patients with T2DM after adjustment for demographic and traditional VDs risk factors (p < 0.001). CONCLUSIONS: Baseline FGF21 is elevated in VDs during diabetes, changes of serum FGF21 levels were appropriately matched to metabolic stress. FGF21can be used as an independent predictor for diagnosing VDs and predicting prognosis.


Asunto(s)
Enfermedades de las Arterias Carótidas , Diabetes Mellitus Tipo 2 , Adulto , Preescolar , Humanos , Estudios Transversales , Factores de Crecimiento de Fibroblastos
9.
BMC Biol ; 20(1): 89, 2022 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-35449002

RESUMEN

BACKGROUND: Medicinal plants have always played an important role in the history of human health. However, the populations and sustainable use of medicinal plants have been severely affected by human activities and climate change. Little is known about the current conservation status and distribution pattern of medicinal plants. In this study, based on accurate geographical distribution information of 9756 medicinal plants, we identified diversity hotspots and conservation gaps, evaluated conservation effectiveness of nature reserves, and predicted suitable habitat areas for medicinal plants in China to provide scientific guidance for their long-term conservation and sustainable use. RESULTS: A total of 150 diversity hotspot grid cells, mainly concentrated in central and southern China, were identified. These only accounted for 5% of the total distribution area but contained 96% of the medicinal plants of the country. The hotspot grid cells included all traditional hotspot areas, but we also detected three new hotspots, namely Mufu-Lushan Mountains, Tianshan-Altai Mountains, and Changbai Mountains. The current national and provincial nature reserves protect 125 hotspot grid cells, which harbor 94% of all medicinal plants. However, 25 hotspot grid cells, distributed in the Tianshan-Altai Mountains and Hengduan Mountains, are located outside the national and provincial nature reserves. An analysis of the predicted effects of climate change indicated that the suitable habitat areas will shift from southern to northern China, and that southern China will face a considerable loss of suitable habitat areas, while the east and west parts of China will encompass remarkably more suitable habitat areas in the future. CONCLUSIONS: The current conservation networks have achieved high conservation effectiveness with regard to medicinal plants; however, the conservation gaps we identified should not be neglected, and conservation planning needs to take into account the predicted shifts of some hotspots of medicinal plants due to climate change.


Asunto(s)
Cambio Climático , Plantas Medicinales , China , Conservación de los Recursos Naturales , Ecosistema , Humanos
10.
Opt Express ; 30(17): 30098-30107, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-36242120

RESUMEN

Stimulated Raman transition is a fundamental method to coherently manipulate quantum states in different physical systems. Phase-coherent dichromatic radiation fields matching the energy level splitting are the key to realizing stimulated Raman transition. Here we demonstrate a flexible-tuning, spectrum-clean and fiber-compatible method to generate a highly phase-coherent and high-power multi-tone laser. This method features the utilization of a broadband fiber Mach-Zehnder modulator working at carrier suppression condition and second harmonic generation. We generate a multi-tone continuous-wave 532 nm laser with a power of 1.5 Watts and utilize it to manipulate the spin and motional states of a trapped 171Yb+ ion via stimulated Raman transition. For spin state manipulation, we acquire an effective Rabi frequency of 2π × 662.3 kHz. Due to the broad bandwidth of the fiber modulator and nonlinear crystal, the frequency gap between tones can be flexibly tuned. Benefiting from the features above, this method can manipulate 171Yb+ and 137Ba+ simultaneously in the multi-species ion trap and has potential to be widely applied in atomic, molecular and optical physics.

11.
Phys Rev Lett ; 129(15): 150402, 2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36269960

RESUMEN

Quantum theory predicts the existence of genuinely tripartite-entangled states, which cannot be obtained from local operations over any bipartite-entangled states and unlimited shared randomness. Some of us recently proved that this feature is a fundamental signature of quantum theory. The state |GHZ_{3}⟩=(|000⟩+|111⟩)/sqrt[2] gives rise to tripartite quantum correlations that cannot be explained by any causal theory limited to bipartite nonclassical common causes of any kind (generalizing entanglement) assisted with unlimited shared randomness. Hence, any conceivable physical theory that would reproduce quantum predictions will necessarily include genuinely tripartite resources. In this Letter, we verify that such tripartite correlations are experimentally achievable. We derive a new device-independent witness capable of falsifying causal theories wherein nonclassical resources are merely bipartite. Using a high-performance photonic |GHZ_{3}⟩ state with fidelities of 0.9741±0.002, we provide a clear experimental violation of that witness by more than 26.3 standard deviations, under the locality and fair sampling assumption. We generalize our Letter to the |GHZ_{4}⟩ state, obtaining correlations that cannot be explained by any causal theory limited to tripartite nonclassical common causes assisted with unlimited shared randomness.

12.
Phys Rev Lett ; 129(6): 060402, 2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-36018648

RESUMEN

Violation of Bell's inequalities shows strong conflict between quantum mechanics and local realism. Loophole-free Bell tests not only deepen understanding of quantum mechanics, but are also important foundations for device-independent (DI) tasks in quantum information. High-dimensional quantum systems offer a significant advantage over qubits for closing the detection loophole. In the symmetric scenario, a detection efficiency as low as 61.8% can be tolerated using four-dimensional states and a four-setting Bell inequality [Phys. Rev. Lett. 104, 060401 (2010)PRLTAO0031-900710.1103/PhysRevLett.104.060401]. For the first time, we show that four-dimensional entangled photons violate a Bell inequality while closing the detection loophole in experiment. The detection efficiency of the four-dimensional entangled source is about 71.7%, and the fidelity of the state is 0.995±0.001. Combining the technique of multicore fibers, the realization of loophole-free high-dimensional Bell tests and high-dimensional quantum DI technologies are promising.

13.
Phys Rev Lett ; 129(3): 030502, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35905332

RESUMEN

We use hyperentanglement to experimentally realize deterministic entanglement swapping based on quantum elegant joint measurements. These are joint projections of two qubits onto highly symmetric, isoentangled bases. We report measurement fidelities no smaller than 97.4%. We showcase the applications of these measurements by using the entanglement swapping procedure to demonstrate quantum correlations in the form of proof-of-principle violations of both bilocal Bell inequalities and more stringent correlation criteria corresponding to full network nonlocality. Our results are a foray into entangled measurements and nonlocality beyond the paradigmatic Bell state measurement and they show the relevance of more general measurements in entanglement swapping scenarios.

14.
Phys Rev Lett ; 129(19): 190503, 2022 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-36399745

RESUMEN

Genuine multipartite entanglement represents the strongest type of entanglement, which is an essential resource for quantum information processing. Standard methods to detect genuine multipartite entanglement, e.g., entanglement witnesses, state tomography, or quantum state verification, require full knowledge of the Hilbert space dimension and precise calibration of measurement devices, which are usually difficult to acquire in an experiment. The most radical way to overcome these problems is to detect entanglement solely based on the Bell-like correlations of measurement outcomes collected in the experiment, namely, device independently. However, it is difficult to certify genuine entanglement of practical multipartite states in this way, and even more difficult to quantify it, due to the difficulty in identifying optimal multipartite Bell inequalities and protocols tolerant to state impurity. In this Letter, we explore a general and robust device-independent method that can be applied to various realistic multipartite quantum states in arbitrary finite dimension, while merely relying on bipartite Bell inequalities. Our method allows us both to certify the presence of genuine multipartite entanglement and to quantify it. Several important classes of entangled states are tested with this method, leading to the detection of genuinely entangled states. We also certify genuine multipartite entanglement in weakly entangled Greenberger-Horne-Zeilinger states, showing that the method applies equally well to less standard states.

15.
Future Oncol ; 18(10): 1245-1258, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35114801

RESUMEN

Aim: This study aimed to develop a predictive model for patients with duodenal carcinoma. Methods: Duodenal carcinoma patients from the Surveillance, Epidemiology, and End Results database (2010-2015) and the First Affiliated Hospital of Nanchang University (2010-2021) were enrolled. A nomogram was constructed according to least absolute shrinkage and selection operator regression analysis, the Akaike information criterion approach and Cox regression analysis. Results: Five independent prognostic factors were significantly associated with the prognosis of the duodenal carcinoma patients. A nomogram was constructed with a C-index in the training and validation cohorts of 0.671 (95% CI: 0.578-0.716) and 0.662 (95% CI: 0.529-0.773), respectively. Conclusion: The established nomogram model provided visualization of the risk of each prognostic factor.


Asunto(s)
Neoplasias Duodenales/diagnóstico , Neoplasias Duodenales/mortalidad , Nomogramas , China/epidemiología , Neoplasias Duodenales/patología , Femenino , Humanos , Estimación de Kaplan-Meier , Metástasis Linfática , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Medición de Riesgo/métodos , Programa de VERF , Estados Unidos/epidemiología
16.
Int J Mol Sci ; 23(16)2022 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-36012217

RESUMEN

Potentially traumatic experiences have been associated with chronic diseases. Epigenetic mechanisms, including DNA methylation (DNAm), have been proposed as an explanation for this association. We examined the association of experiences of trauma with epigenome-wide DNAm among African American mothers (n = 236) and their children aged 3-5 years (n = 232; N = 500), using the Life Events Checklist-5 (LEC) and Traumatic Events Screening Inventory-Parent Report Revised (TESI-PRR). We identified no DNAm sites significantly associated with potentially traumatic experience scores in mothers. One CpG site on the ENOX1 gene was methylome-wide-significant in children (FDR-corrected q-value = 0.05) from the TESI-PRR. This protein-coding gene is associated with mental illness, including unipolar depression, bipolar, and schizophrenia. Future research should further examine the associations between childhood trauma, DNAm, and health outcomes among this understudied and high-risk group. Findings from such longitudinal research may inform clinical and translational approaches to prevent adverse health outcomes associated with epigenetic changes.


Asunto(s)
Negro o Afroamericano , Metilación de ADN , Negro o Afroamericano/genética , Niño , Epigénesis Genética , Epigenoma , Epigenómica , Femenino , Humanos , Madres
17.
J Environ Manage ; 305: 114364, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34959060

RESUMEN

Food waste (FW) has received increasing attention because of its immense production quantities and significance to resource and environmental impacts related to disposal approaches. We combined life cycle assessment (LCA) with society's willingness to pay (WTP) index to evaluate energy, water, and environmental impacts on three food waste-to-energy (FWTE) options in China. For anaerobic digestion (AD) mode, the results showed that 1140 MJ of energy consumption could be saved by power generation from methane, power transmission, and biodiesel production from per ton of FW; the cost of climate change for treating FW was 137.8 kg CO2e t-1 FW, failing to be climate-sound due to the end life of digestate in practice. The total impact to AD mode in the form of monetized value for WTP was 13.3 CNY t-1 FW, of which the collection and transportation, pretreatment, AD reaction, wastewater treatment, biodiesel production, and residue landfilling stages contributed by 10.5%, 6.5%, 19.3%, 27.6%, 4.7%, and 75.7%, respectively, while biogas utilization offset it by 43.9%. Notably, a considerable amount of water used in AD prevented it from showing an advantage compared to incineration (-5.1 CNY t-1 FW), which performed best overall attributing to the generated electricity compensated for primary energy demand, water, and terrestrial acidification to a great extent. Landfilling turned out to be an unappealing FW disposal method due to the low landfill gas capture ratio. Given that AD is touted for its environmental benefits, potential approaches-such as developing a reliable and supportive technology to facilitate digestate recycling into agriculture-were discussed to improve its competitiveness and attractiveness. Our study employed a way to accumulate and compare impact indicators to better interpret FW management impacts and advantages, considering energy recovery, resource recycling, and the environment.


Asunto(s)
Eliminación de Residuos , Administración de Residuos , Animales , Alimentos , Incineración , Estadios del Ciclo de Vida
18.
J Cell Mol Med ; 25(8): 4062-4072, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33609076

RESUMEN

Previous studies showed that the chemotherapeutic effect of temozolomide (TMZ) and vincristine (VCR) against glioma might be blunted by the co-culture with astrocytes, and connexin-43 (CX43) was thought to play a vital role in the communication between glioma cells and astrocytes. In this study, we aimed to investigate the combined chemotherapeutic effect of AS602801 and TMZ/ VCR in glioma cells both. Dye transfer assay was used to evaluate the gap junction activity between U251 cells and astrocytes. Western blot and immunohistochemistry were carried out to analyse the expression of p-JNK, CX43 and CASP-3 proteins treated under different conditions. AS602801 significantly suppressed the gap junction activity between U251 cells and astrocytes. The expression of p-JNK and CX43 was remarkably inhibited by AS602801. TMZ/VCR-induced apoptosis of glioma cells was effectively enhanced by AS602801 treatment. Accordingly, the inhibitory role of TMZ/VCR in the expression of p-JNK, CX43 and CASP-3 in glioma cells was notably restored by AS602801. Furthermore, in a glioma cell xenograft, AS602801 showed an apparent capability to enhance TMZ/VCR-induced tumour cell apoptosis through altering the expression of p-JNK, CX43 and CASP-3. The findings of this study demonstrated that the co-culture of glioma cells with astrocytes blunted the tumour killing effect of TMZ and VCR. AS602801 down-regulated CX43 expression by inhibiting JNK. And AS602801 also sensitized glioma cells to TMZ/VCR by blocking the gap junction communication between glioma cells and astrocytes via down-regulating CX43, indicating its potential role as a novel adjuvant chemotherapeutic agent in the treatment of glioma.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Astrocitos/efectos de los fármacos , Comunicación Celular , Resistencia a Antineoplásicos/efectos de los fármacos , Uniones Comunicantes/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioma/tratamiento farmacológico , Animales , Apoptosis , Astrocitos/fisiología , Benzotiazoles/administración & dosificación , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Proliferación Celular , Técnicas de Cocultivo , Conexina 43/metabolismo , Uniones Comunicantes/fisiología , Glioma/metabolismo , Glioma/patología , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , Pirimidinas/administración & dosificación , Temozolomida/administración & dosificación , Células Tumorales Cultivadas , Vincristina/administración & dosificación , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Opt Express ; 29(16): 24674-24683, 2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34614818

RESUMEN

We demonstrate a laser frequency stabilization method with large tuning range to stabilize a UV laser by installing piezoelectric ceramic actuators into a Fabry-Pérot cavity with an ultra-low expansion spacer. To suppress piezoelectric drift, a two-layer symmetrical structure is adopted for the piezoelectric actuator, and a 14.7 GHz tuning range is achieved. The short-term drift of the piezoelectric ceramics caused by temperature and creep is eliminated, and the long-term drift is 0.268 MHz/h when the Fabry-Pérot cavity is sealed in a chamber without a vacuum environment. The long-term frequency drift is mainly caused by stress release and is eliminated by compensating the cavity voltage with an open loop. Without the need for an external reference or a vacuum environment, the laser frequency stabilization system is greatly simplified, and it can be extended to wavelengths ranging from ultraviolet to infrared. Owing to its simplicity, stability, and large tuning range, it is applicable in cold atom and trapped ion experiments.

20.
Opt Express ; 29(23): 38488-38496, 2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34808901

RESUMEN

In research on hybrid quantum networks, visible or near-infrared frequency conversion has been realized. However, technical limitations mean that there have been few studies involving the ultraviolet band, and unfortunately the wavelengths of the rare-earth or alkaline-earth metal atoms or ions that are used widely in research on quantum information are often in the UV band. Therefore, frequency conversion of the ultraviolet band is very important. In this paper, we demonstrate a quantum frequency conversion between ultraviolet and visible wavelengths by fabricating waveguides in a period-poled MgO:LiTaO3 crystal with a laser writing system, which will be used to connect the wavelength of the dipole transition of 171Yb+ at 369.5 nm and the absorption wavelength of Eu3+ at 580 nm in a solid-state quantum memory system. An external conversion efficiency of 0.85% and a signal-to-noise ratio of greater than 500 are realized with a pumping power of 3.28 W at 1018 nm. Furthermore, we complete frequency conversion of the classical polarization state by means of a symmetric optical setup based on the fabricated waveguide, and the process fidelity of the conversion is (96.13 ± 0.021)%. This converter paves the way for constructing a hybrid quantum network and realizing a quantum router in the ultraviolet band in the future.

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