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1.
Nature ; 600(7887): 75-80, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34853455

RESUMEN

Nonlinear wave-matter interactions may give rise to solitons, phenomena that feature inherent stability in wave propagation and unusual spectral characteristics. Solitons have been created in a variety of physical systems and have had important roles in a broad range of applications, including communications, spectroscopy and metrology1-4. In recent years, the realization of dissipative Kerr optical solitons in microcavities has led to the generation of frequency combs in a chip-scale platform5-10. Within a cavity, photons can interact with mechanical modes. Cavity optomechanics has found applications for frequency conversion, such as microwave-to-optical or radio-frequency-to-optical11-13, of interest for communications and interfacing quantum systems operating at different frequencies. Here we report the observation of mechanical micro-solitons excited by optical fields in an optomechanical microresonator, expanding soliton generation in optical resonators to a different spectral window. The optical field circulating along the circumference of a whispering gallery mode resonator triggers a mechanical nonlinearity through optomechanical coupling, which in turn induces a time-varying periodic modulation on the propagating mechanical mode, leading to a tailored modal dispersion. Stable localized mechanical wave packets-mechanical solitons-can be realized when the mechanical loss is compensated by phonon gain and the optomechanical nonlinearity is balanced by the tailored modal dispersion. The realization of mechanical micro-solitons driven by light opens up new avenues for optomechanical technologies14 and may find applications in acoustic sensing, information processing, energy storage, communications and surface acoustic wave technology.

2.
Opt Express ; 32(1): 179-187, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38175047

RESUMEN

The Tavis-Cummings model is intensively investigated in quantum optics and has important applications in generation of multi-atom entanglement. Here, we employ a superconducting circuit quantum electrodynamic system to study a modified Tavis-Cummings model with directly-coupled atoms. In our device, three superconducting artificial atoms are arranged in a chain with direct coupling through fixed capacitors and strongly coupled to a transmission line resonator. By performing transmission spectrum measurements, we observe different anticrossing structures when one or two qubits are resonantly coupled to the resonator. In the case of the two-qubit Tavis-Cummings model without qubit-qubit interaction, we observe two dips at the resonance point of the anticrossing. The splitting of these dips is determined by Δ λ=2g12+g32, where g1 and g3 are the coupling strengths between Qubit 1 and the resonator, and Qubit 3 and the resonator, respectively. The direct coupling J12 between the two qubits results in three dressed states in the two-qubit Tavis-Cummings model at the frequency resonance point, leading to three dips in the transmission spectrum. In this case, the distance between the two farthest and asymmetrical dips, arising from the energy level splitting, is larger than in the previous case. The frequency interval between these two dips is determined by the difference in eigenvalues (Δ λ=ε 1+-ε 1-), obtained through numerical calculations. What we believe as novel and intriguing experimental results may potentially advance quantum optics experiments, providing valuable insights for future research.

3.
Exp Cell Res ; 424(1): 113473, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36634743

RESUMEN

Long non-coding RNA (lncRNA) anomalies cause early ovarian failure. LncRNA nuclear enriched abundant transcript 1 (NEAT1) was down-regulated in premature ovarian failure (POF) mice and connected to the illness, however, the mechanism remained unclear. The levels of gene and protein were measured by using quantitative real-time polymerase chain reaction, Western blot, and immunofluorescence. Follicle stimulating hormone (FSH), estradiol (E2), and luteinizing hormone (LH) levels were determined using enzyme-linked immunosorbent assay (ELISA). 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and flow cytometry were used to determine cell viability and apoptosis. The interaction of NEAT1, miR-654, and stanniocalcin-2 (STC2) was verified by dual-luciferase reporter assay or RNA binding protein immunoprecipitation (RIP) assays. The results showed NEAT1 and STC2 down-regulated, while miR-654 up-regulated in POF mice. Overexpression of NEAT1 reduced apoptosis and autophagy in cyclophosphamide (CTX)-treated ovarian granulosa cells (OGCs), and Bax, cleaved-caspase3, LC3B, LC3II/LC3I ratio were decreased and Bcl-2 and p62 were raised. NEAT1 suppressed miR-654 expression by directly targeting miR-654. The inhibition of NEAT1 overexpression on apoptosis and autophagy in OGCs was reversed by miR-654 mimics. STC2 was a target gene of miR-654, and miR-654 inhibitor reduced the apoptosis and autophagy by regulating the STC2/MAPK axis. To sum up, NEAT1 reduced miR-654 expression and modulated the STC2/MAPK pathway to decrease apoptosis and autophagy in POF, indicating a potential therapeutic target.


Asunto(s)
Apoptosis , Autofagia , Células de la Granulosa , MicroARNs , ARN Largo no Codificante , Animales , Ratones , Apoptosis/genética , Autofagia/genética , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Transducción de Señal , Células de la Granulosa/metabolismo , Células de la Granulosa/patología
4.
Opt Express ; 31(22): 36836-36844, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-38017825

RESUMEN

Order is one of the most important concepts to interpret various phenomena such as the emergence of turbulence and the life-evolution process. The generation of laser can also be treated as an ordering process in which the interaction between the laser beam and the gain medium leads to the correlation between photons in the output optical field. Here, we demonstrate experimentally in a hybrid Raman-laser-optomechanical system that an ordered Raman laser can be generated from an entropy-absorption process by a chaotic optomechanical resonator. When the optomechanical resonator is chaotic or disordered enough, the Raman-laser field is in an ordered lasing mode. This can be interpreted by the entropy transfer from the Raman-laser mode to the chaotic motion mediated by optomechanics. Different order parameters, such as the box-counting dimension, the maximal Lyapunov exponent, and the Kolmogorov entropy, are introduced to quantitatively analyze this entropy transfer process, by which we can observe the order transfer between the Raman-laser mode and the optomechanical resonator. Our study presents a new mechanism of laser generation and opens up new dimensions of research such as the modulation of laser by optomechanics.

5.
Phys Rev Lett ; 131(10): 103602, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37739354

RESUMEN

Optical mirrors determine cavity properties by means of light reflection. Imperfect reflection gives rise to open cavities with photon loss. We study an open cavity made of atom-dimer mirrors with a tunable reflection spectrum. We find that the atomic cavity shows anti-PT symmetry. The anti-PT phase transition controlled by atomic couplings in mirrors indicates the emergence of two degenerate cavity supermodes. Interestingly, a threshold of mirror reflection is identified for realizing strong coherent cavity-atom coupling. This reflection threshold reveals the criterion of atomic mirrors to produce a good cavity. Moreover, cavity quantum electrodynamics with a probe atom shows mirror-tuned properties, including reflection-dependent polaritons formed by the cavity and probe atom. Our Letter presents a non-Hermitian theory of an anti-PT atomic cavity, which may have applications in quantum optics and quantum computation.

7.
Ecotoxicol Environ Saf ; 252: 114581, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36731179

RESUMEN

The codling moth Cydia pomonella (Lepidoptera: Tortricidae) is a major invasive pest of pome fruits and walnuts worldwide. Lambda-cyhalothrin (LCT) and abamectin (AM) have been frequently used in C. pomonella control, but control of this pest is very difficult because shortly after hatching, larvae of this insect bore tunnels and hide inside host plant fruit. In this study, a simulated field spray bioassay method was developed against neonate larvae of C. pomonella and concentration-response bioassays were conducted to evaluate the susceptibility of the neonate larvae to LCT and AM. Exposure of neonate larvae to sublethal concentration (LC30) of LCT or AM significantly reduced the survival rate of larvae (4th and 5th instars), lowered the mean weight of larvae and pupae, and decreased the daily maximal number of eggs laid and the total number of eggs laid (fecundity) per female. The sublethal effects, including reduced body mass, mean fecundity and net reproductive rate, extended mean generation time, and shortened oviposition period, were also found in transgenerational offspring. Furthermore, the transgenerational maternal effects were more obvious for AM than LCT, in comparison to the control. Additionally, the estimated population size was decreased by exposure to LC30 of LCT and AM, and the observed reduction of fecundity and population size within and across generations was likely the result of the downregulation of the reproduction-related vitellogenin gene (CpVg) after exposure to LC30 of LCT and AM. These results provide a better understanding of the overall effects of LCT and AM on C. pomonella and the transgenerational effects which should be taken into consideration when using insecticides in order to control C. pomonella.


Asunto(s)
Insecticidas , Mariposas Nocturnas , Piretrinas , Animales , Femenino , Piretrinas/toxicidad , Larva , Insecticidas/toxicidad , Reproducción
8.
Pharmacol Res ; 175: 105983, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34822972

RESUMEN

Angiogenesis plays an important role in the growth and metastasis of solid tumors including melanoma. Inhibiting tumor-associated angiogenesis is a tactic in treating melanoma. Dioscin restrains angiogenesis in colon tumor and has anti-melanoma effects in cell and animal models. In a previous study, we found that dioscin inhibits Src/STAT3 signaling in melanoma cells. Activation of the Src/STAT3 pathway has been shown to promote tumor angiogenesis. This study aimed to determine whether dioscin's anti-melanoma effects is related to inhibiting Src/STAT3 signaling-mediated angiogenesis. In a B16F10 allograft mouse model, we found that dioscin inhibited melanoma growth and angiogenesis. To exclude the impact of tumor growth on angiogenesis, a chicken chorioallantoic membrane (CAM) model was used to verify the anti-angiogenic effect of dioscin. Results showed that dioscin suppressed vessel formation in CAM. To determine if tumor secreted pro-angiogenic cytokines are involved in the anti-angiogenic effect of dioscin, conditioned media from dioscin-treated A375 melanoma cells were used to culture human umbilical vein endothelial cells (HUVECs), and tube formation was monitored. It was observed that the tube formation of HUVECs was inhibited. Mechanistic studies revealed that dioscin inhibited the activation of Src and STAT3, and lowered mRNA and protein levels of STAT3 transcriptionally-regulated genes, in B16F10 melanomas. ELISA assays showed that dioscin decreased the secretion of MMP-2, MMP-9 and VEGF from A375 cells. Over-activation of STAT3 lessened the effects of dioscin in decreasing the secretion of pro-angiogenic cytokines from melanoma cells, and in inhibiting tube formation of HUVECs cultured with conditioned media from melanoma cell cultures. In summary, we for the first time demonstrated that inhibiting Src/STAT3 signaling-mediated angiogenesis is involved in the anti-melanoma effects of dioscin. This study provides further pharmacological groundwork for developing dioscin as an anti-melanoma agent.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Diosgenina/análogos & derivados , Melanoma Experimental/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Factor de Transcripción STAT3/antagonistas & inhibidores , Familia-src Quinasas/antagonistas & inhibidores , Inhibidores de la Angiogénesis/farmacología , Animales , Línea Celular Tumoral , Diosgenina/farmacología , Diosgenina/uso terapéutico , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Masculino , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones Endogámicos C57BL , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Factor de Transcripción STAT3/metabolismo , Carga Tumoral/efectos de los fármacos , Familia-src Quinasas/metabolismo
9.
Brain ; 144(10): 3050-3060, 2021 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-33876820

RESUMEN

The unc-13 homolog B (UNC13B) gene encodes a presynaptic protein, mammalian uncoordinated 13-2 (Munc13-2), which is highly expressed in the brain-predominantly in the cerebral cortex-and plays an essential role in synaptic vesicle priming and fusion, potentially affecting neuronal excitability. However, the functional significance of the UNC13B mutation in human disease is not known. In this study, we screened for novel genetic variants in a cohort of 446 unrelated cases (families) with partial epilepsy without acquired causes by trio-based whole-exome sequencing. UNC13B variants were identified in 12 individuals affected by partial epilepsy and/or febrile seizures from eight unrelated families. The eight probands all had focal seizures and focal discharges in EEG recordings, including two patients who experienced frequent daily seizures and one who showed abnormalities in the hippocampus by brain MRI; however, all of the patients showed a favourable outcome without intellectual or developmental abnormalities. The identified UNC13B variants included one nonsense variant, two variants at or around a splice site, one compound heterozygous missense variant and four missense variants that cosegregated in the families. The frequency of UNC13B variants identified in the present study was significantly higher than that in a control cohort of Han Chinese and controls of the East Asian and all populations in the Genome Aggregation Database (gnomAD). Computational modelling, including hydrogen bond and docking analyses, suggested that the variants lead to functional impairment. In Drosophila, seizure rate and duration were increased by Unc13b knockdown compared to wild-type flies, but these effects were less pronounced than in sodium voltage-gated channel alpha subunit 1 (Scn1a) knockdown Drosophila. Electrophysiological recordings showed that excitatory neurons in Unc13b-deficient flies exhibited increased excitability. These results indicate that UNC13B is potentially associated with epilepsy. The frequent daily seizures and hippocampal abnormalities but ultimately favourable outcome under anti-epileptic therapy in our patients indicate that partial epilepsy caused by UNC13B variant is a clinically manageable condition.


Asunto(s)
Epilepsias Parciales/diagnóstico por imagen , Epilepsias Parciales/genética , Variación Genética/genética , Proteínas del Tejido Nervioso/genética , Adolescente , Adulto , Secuencia de Aminoácidos , Animales , Animales Modificados Genéticamente , Niño , Preescolar , Drosophila , Epilepsias Parciales/fisiopatología , Femenino , Humanos , Masculino , Resultado del Tratamiento
10.
Phys Rev Lett ; 127(25): 250402, 2021 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-35029435

RESUMEN

A primary motivation for studying topological matter regards the protection of topological order from its environment. In this work, we study a topological emitter array coupled to an electromagnetic environment. The photon-emitter coupling produces nonlocal interactions between emitters. Using periodic boundary conditions for all ranges of environment-induced interactions, the chiral symmetry inherent to the emitter array is preserved. This chiral symmetry protects the Hamiltonian and induces parity in the Lindblad operator. A topological phase transition occurs at a critical photon-emitter coupling related to the energy spectrum width of the emitter array. Interestingly, the critical point nontrivially changes the dissipation rates of edge states, yielding a dissipative topological phase transition. In the protected topological phase, edge states suffer from environment-induced dissipation for weak photon-emitter coupling. However, strong coupling leads to robust dissipationless edge states with a window at the emitter spacing. Our work shows the potential to manipulate topological quantum matter with electromagnetic environments.

11.
Phys Rev Lett ; 124(2): 023603, 2020 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-32004058

RESUMEN

Exploring the properties and applications of topological quantum states is essential to better understand topological matter. Here, we theoretically study a quasi-one-dimensional topological atom array. In the low-energy regime, the atom array is equivalent to a topological superatom. Driving the superatom in a cavity, we study the interaction between light and topological quantum states. We find that the edge states exhibit topology-protected quantum coherence, which can be characterized from the photon transmission. This quantum coherence helps us to find a superradiance-subradiance transition, and we also study its finite-size scaling behavior. The superradiance-subradiance transition also exists in symmetry-breaking systems. More importantly, it is shown that the quantum coherence of the subradiant edge state is robust to random noises, allowing the superatom to work as a topologically protected quantum memory. We suggest a relevant experiment with three-dimensional circuit QED. Our study may have applications in quantum computation and quantum optics based on topological edge states.

12.
Biol Pharm Bull ; 43(8): 1267-1271, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32741948

RESUMEN

Primary liver cancer is a lethal cancer. The phosphatidylinositol 3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) pathway has been implicated in the pathogenesis of liver cancer. Gomisin N (GN), a lignan isolated from the dried fruits of Schisandra chinensis (Turca.) Baill., has been reported to reduce viability of, and induce apoptosis in, HepG2 liver cancer cells. In preadipocytes, GN was found to inhibit Akt activity. In the present study, Akt signaling-related anti-liver cancer mechanisms of GN were investigated. We confirmed that GN reduces cell viability of, and triggers apoptosis in, more liver cancer cell lines. Mechanistic studies revealed that GN lowers protein levels of phospho-PI3K (p85 tyrosine (Tyr)458), phospho-Akt (serine (Ser)473), and Akt downstream molecules Mcl-1 in HepG2 and HCCLM3 cells. Meanwhile, GN activates mTOR and inhibits ULK1 (a negative downstream effector of mTOR) activities. Activation of mTOR has been reported to suppress ULK1 activity and repress autophagy. Indeed, we observed that GN inhibits autophagy in liver cancer cells. In summary, we for the first time demonstrated that GN inhibits the PI3K-Akt pathway and regulates the mTOR-ULK1 pathway in liver cancer cells.


Asunto(s)
Antineoplásicos/farmacología , Homólogo de la Proteína 1 Relacionada con la Autofagia/fisiología , Péptidos y Proteínas de Señalización Intracelular/fisiología , Lignanos/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Fosfatidilinositol 3-Quinasa/fisiología , Compuestos Policíclicos/farmacología , Proteínas Proto-Oncogénicas c-akt/fisiología , Serina-Treonina Quinasas TOR/fisiología , Homólogo de la Proteína 1 Relacionada con la Autofagia/antagonistas & inhibidores , Línea Celular Tumoral , Ciclooctanos/farmacología , Humanos , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos
13.
Pharmacol Res ; 142: 115-126, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30797070

RESUMEN

A traditional Chinese medicine (TCM) formula (SL) comprising Sophorae Flos and Lonicerae Japonicae Flos was used for treating melanoma in ancient China. We have previously shown that an ethanolic extract of SL (SLE) possesses anti-melanoma effects and suppresses STAT3 signaling in vitro and in vivo. STAT3 has been linked to the development of melanoma immunosuppressive microenvironment. In this work, we investigated whether SLE inhibits melanoma growth by reprogramming the tumor microenvironment in mouse and co-culture cell models. In B16F10 melanoma-bearing mice, we found that intragastric administration of SLE (1.2 g/kg) dramatically inhibited tumor growth. This observation was associated with the downregulation of protein levels of phospho-STAT3 (Tyr 705) and STAT3-regulated immunosuppressive cytokines, and mRNA levels of STAT3-targeted genes involved in tumor growth and immune evasion. We also observed increased Th, Tc and dendritic cells in the melanomas and spleens in SLE-treated mice compared to that in control mice. In a co-culture system composed of B16F10 cells and mouse primary splenic lymphocytes, it was found that SLE not only inhibited STAT3 activation in B16F10 cells, but also downregulated mRNA levels of STAT3-targeted genes in the splenic lymphocytes. In this co-culture setting, SLE decreased the levels of STAT3-regulated immunosuppressive cytokines, increased the percentages of Th, Tc and dendritic cells as well. Furthermore, effects of SLE on STAT3 phosphorylation, cytokine levels and immune cell subtype percentages were significantly weaker in the B16STAT3C cells (stable cells harboring a constitutively active STAT3 variant STAT3C)/splenic lymphocytes co-culture system than in the B16V cells (cells stably transfected with the empty vector)/splenic lymphocytes co-culture system, indicating that STAT3 over-activation diminishes SLE's effects. In summary, our findings indicate that reprograming the immune microenvironment, partially mediated by inhibiting STAT3 signaling, contributes to the anti-melanoma mechanisms of SLE. This study provides further pharmacological groundwork for developing SLE as a modern agent for melanoma prevention/treatment, and supports the notion that reprograming immunosuppressive microenvironment is a viable anti-melanoma strategy.


Asunto(s)
Antineoplásicos/farmacología , Melanoma Experimental/inmunología , Extractos Vegetales/farmacología , Factor de Transcripción STAT3/inmunología , Neoplasias Cutáneas/inmunología , Sophora , Microambiente Tumoral/efectos de los fármacos , Animales , Antineoplásicos/uso terapéutico , Técnicas de Cocultivo , Flores , Lonicera , Linfocitos , Masculino , Medicina Tradicional China , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/patología , Ratones Endogámicos C57BL , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/inmunología , Neovascularización Patológica/patología , Extractos Vegetales/uso terapéutico , Transducción de Señal/efectos de los fármacos , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Microambiente Tumoral/inmunología
14.
Cochrane Database Syst Rev ; 8: CD013107, 2019 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-31436846

RESUMEN

BACKGROUND: Chronic hepatitis B is a liver disease associated with high morbidity and mortality. Chronic hepatitis B requires long-term management aiming to reduce the risks of hepatocellular inflammatory necrosis, liver fibrosis, decompensated liver cirrhosis, liver failure, and liver cancer, as well as to improve health-related quality of life. Acupuncture is being used to decrease discomfort and improve immune function in people with chronic hepatitis B. However, the benefits and harms of acupuncture still need to be established in a rigorous way. OBJECTIVES: To assess the benefits and harms of acupuncture versus no intervention or sham acupuncture in people with chronic hepatitis B. SEARCH METHODS: We undertook electronic searches of the Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE, Embase, LILACS, Science Citation Index Expanded, Conference Proceedings Citation Index - Science, China National Knowledge Infrastructure (CNKI), Chongqing VIP (CQVIP), Wanfang Data, and SinoMed to 1 March 2019. We also searched the World Health Organization International Clinical Trials Registry Platform (www.who.int/ictrp), ClinicalTrials.gov (www.clinicaltrials.gov/), and the Chinese Clinical Trial Registry (ChiCTR) for ongoing or unpublished trials until 1 March 2019. SELECTION CRITERIA: We included randomised clinical trials, irrespective of publication status, language, and blinding, comparing acupuncture versus no intervention or sham acupuncture in people with chronic hepatitis B. We included participants of any sex and age, diagnosed with chronic hepatitis B as defined by the trialists or according to guidelines. We allowed co-interventions when the co-interventions were administered equally to all intervention groups. DATA COLLECTION AND ANALYSIS: Review authors in pairs individually retrieved data from reports and through correspondence with investigators. Primary outcomes were all-cause mortality, proportion of participants with one or more serious adverse events, and health-related quality of life. Secondary outcomes were hepatitis B-related mortality, hepatitis B-related morbidity, and adverse events considered not to be serious. We presented the pooled results as risk ratios (RRs) with 95% confidence intervals (CIs). We assessed the risks of bias using risk of bias domains with predefined definitions. We put more weight on the estimate closest to zero effect when results with fixed-effect and random-effects models differed. We evaluated the certainty of evidence using GRADE. MAIN RESULTS: We included eight randomised clinical trials with 555 randomised participants. All included trials compared acupuncture versus no intervention. These trials assessed heterogeneous acupuncture interventions. All trials used heterogeneous co-interventions applied equally in the compared groups. Seven trials included participants with chronic hepatitis B, and one trial included participants with chronic hepatitis B with comorbid tuberculosis. All trials were assessed at overall high risk of bias, and the certainty of evidence for all outcomes was very low due to high risk of bias for each outcome, imprecision of results (the confidence intervals were wide), and publication bias (small sample size of the trials, and all trials were conducted in China). Additionally, 79 trials lacked the necessary methodological information to ensure their inclusion in our review.None of the included trials aim to assess all-cause mortality, serious adverse events, health-related quality of life, hepatitis B-related mortality, and hepatitis B-related morbidity. We are uncertain whether acupuncture, compared with no intervention, has an effect regarding adverse events considered not to be serious (RR 0.67, 95% CI 0.43 to 1.06; I² = 0%; 3 trials; 203 participants; very low-certainty evidence) or detectable hepatitis B e-antigen (HBeAg) (RR 0.64, 95% CI 0.11 to 3.68; I² = 98%; 2 trials; 158 participants; very low-certainty evidence). Acupuncture showed a reduction in detectable hepatitis B virus (HBV) DNA (a non-validated surrogate outcome; RR 0.45, 95% CI 0.27 to 0.74; 1 trial, 58 participants; very low-certainty evidence). We are uncertain whether acupuncture has an effect regarding the remaining separately reported adverse events considered not to be serious.Three of the eight included trials received academic funding from government or hospital. None of the remaining five trials reported information on funding. AUTHORS' CONCLUSIONS: The clinical effects of acupuncture for chronic hepatitis B remain unknown. The included trials lacked data on all-cause mortality, health-related quality of life, serious adverse events, hepatitis-B related mortality, and hepatitis-B related morbidity. The vast number of excluded trials lacked clear descriptions of their design and conduct. Whether acupuncture influences adverse events considered not to be serious is uncertain. It remains unclear if acupuncture affects HBeAg, and if it is associated with reduction in detectable HBV DNA. Based on available data from only one or two small trials on adverse events considered not to be serious and on the surrogate outcomes HBeAg and HBV DNA, the certainty of evidence is very low. In view of the wide usage of acupuncture, any conclusion that one might try to draw in the future should be based on data on patient and clinically relevant outcomes, assessed in large, high-quality randomised sham-controlled trials with homogeneous groups of participants and transparent funding.


Asunto(s)
Terapia por Acupuntura/métodos , Hepatitis B Crónica/terapia , Humanos , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
15.
Phys Rev Lett ; 120(8): 083602, 2018 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-29543019

RESUMEN

Quantum networks will enable extraordinary capabilities for communicating and processing quantum information. These networks require a reliable means of storage, retrieval, and manipulation of quantum states at the network nodes. A node receives one or more coherent inputs and sends a conditional output to the next cascaded node in the network through a quantum channel. Here, we demonstrate this basic functionality by using the quantum interference mechanism of electromagnetically induced transparency in a transmon qubit coupled to a superconducting resonator. First, we apply a microwave bias, i.e., drive, to the qubit-cavity system to prepare a Λ-type three-level system of polariton states. Second, we input two interchangeable microwave signals, i.e., a probe tone and a control tone, and observe that transmission of the probe tone is conditional upon the presence of the control tone that switches the state of the device with up to 99.73% transmission extinction. Importantly, our electromagnetically induced transparency scheme uses all dipole allowed transitions. We infer high dark state preparation fidelities of >99.39% and negative group velocities of up to -0.52±0.09 km/s based on our data.

16.
Phys Rev Lett ; 117(11): 110802, 2016 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-27661674

RESUMEN

We propose and analyze a new approach based on parity-time (PT) symmetric microcavities with balanced gain and loss to enhance the performance of cavity-assisted metrology. We identify the conditions under which PT-symmetric microcavities allow us to improve sensitivity beyond what is achievable in loss-only systems. We discuss the application of PT-symmetric microcavities to the detection of mechanical motion, and show that the sensitivity is significantly enhanced near the transition point from unbroken- to broken-PT regimes. Our results open a new direction for PT-symmetric physical systems and it may find use in ultrahigh precision metrology and sensing.

17.
Phys Rev Lett ; 115(22): 223603, 2015 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-26650305

RESUMEN

A single superconducting artificial atom can be used for coupling electromagnetic fields up to the single-photon level due to an easily achieved strong coupling regime. Bringing a pair of harmonic oscillators into resonance with the transitions of a three-level atom converts atomic spontaneous processes into correlated emission dynamics. We present the experimental demonstration of two-mode correlated emission lasing in harmonic oscillators coupled via a fully controllable three-level superconducting quantum system (artificial atom). The correlation of emissions with two different colors reveals itself as equally narrowed linewidths and quenching of their mutual phase diffusion. The mutual linewidth is more than 4 orders of magnitude narrower than the Schawlow-Townes limit. The interference between the different color lasing fields demonstrates that the two-mode fields are strongly correlated.

18.
J Agric Food Chem ; 72(1): 363-377, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38134348

RESUMEN

While previous studies have reported G protein-coupled receptor (GPCR)-mediated insecticide resistance in various arthropods, the understanding of GPCR-associated resistance mechanisms in Cydia pomonella remains limited. In this study, a total of 95 CpGPCR genes categorized into four families were identified in C. pomonella. Results revealed high expression levels of the majority of the CpGPCRs during the first larval stage and in the head of C. pomonella. Exposure to lambda-cyhalothrin significantly increased the expression of 15 CpGPCRs, including CpGPCR70, which is highly expressed in all larval stages and shows the highest expression in the midgut. RNA interference (RNAi) demonstrated that downregulation of CpGPCR70 leads to reduced expression of key resistance-related genes and a decreased tolerance of larvae to lambda-cyhalothrin. These findings indicate that CpGPCR70 plays a crucial role in regulating the expression of detoxifying genes involved in lambda-cyhalothrin resistance, offering valuable insights for the development of more effective pest control strategies.


Asunto(s)
Insecticidas , Mariposas Nocturnas , Piretrinas , Humanos , Animales , Piretrinas/farmacología , Piretrinas/metabolismo , Mariposas Nocturnas/metabolismo , Nitrilos/farmacología , Nitrilos/metabolismo , Larva , Insecticidas/farmacología , Insecticidas/metabolismo
19.
Front Pharmacol ; 15: 1413463, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38881868

RESUMEN

Introduction: Hepatocellular carcinoma (HCC) has been a highly common and pathological disease worldwide, while current therapeutic regimens have limitations. Chebulae Fructus, a common herbal medicine in Asia, has been documented to exert potential therapeutic effects on HCC in ancient medicine clinical practice. However, the molecular mechanism underlying its inhibitory effects on HCC requires further investigation. Methods: In this study, the anti-HCC effect of the aqueous extract of Chebulae Fructus (CFE) on human HCC and its underlying mechanism were evaluated. Assays including CCK8, EdU staining, crystal violet staining, cell clone formation, flow cytometry, wound healing, and transwell were used in vitro. The cell-derived xenograft (CDX) and patient-derived xenograft (PDX) models were used in vivo. Transcriptomics analysis, qRT-PCR, ELISA, IHC staining, and Western blotting were employed to determine the mechanism of action of CFE. Results: The results demonstrate that CFE effectively suppressed the proliferation and activity of HepG2 and PLC/PRF/5 HCC cells. CFE also induced apoptosis, and suppressed the migration and invasion abilities of these cells. Furthermore, CFE exhibited inhibitory effects on tumor growth in both H22 and PLC/PRF/5 mouse models, as well as in an HCC PDX model which is derived from patient tumor samples. Moreover, it was identified that CFE treatment specifically suppressed the Apelin/APJ system in HCC cells and tumor tissues. To investigate the role of the Apelin/APJ system in mediating the effects of CFE treatment, an APJ overexpressed cell model is established. Interestingly, it was found that the overexpression of APJ significantly diminished the inhibitory effects of CFE on HCC in vitro. Discussion: Collectively, this study provides compelling evidence that CFE exerts significant anti-HCC effects in cell and animal models. Moreover, our findings suggest that the Apelin/APJ system may play a vital role in the therapeutic effects of CFE against HCC.

20.
Front Bioeng Biotechnol ; 11: 999137, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37091332

RESUMEN

Osteons are composed of concentric lamellar structure, the concentric lamellae are composed of periodic thin and thick sub-lamellae, and every 5 sub-lamellae is a cycle, the periodic helix angle of mineralized collagen fibers in two adjacent sub-lamellae is 30°. Four biomimetic models with different fiber helix angles were established and fabricated according to the micro-nano structure of osteon. The effects of the fiber periodic helical structure on impact characteristic and energy dissipation of multi-layer biomimetic composite were investigated. The calculation results indicated that the stress distribution, contact characteristics and fiber failur during impact, and energy dissipation of the composite are affected by the fiber helix angle. The stress concentration of composite materials under external impact can be effectively improved by adjusting the fiber helix angle when the material composition and material performance parameters are same. Compared with the sample30, the maximum stress of sample60 and sample90 increases by 38.1% and 69.8%, respectively. And the fiber failure analysis results shown that the model with a fiber helix angle of 30° has a better resist impact damage. The drop-weight test results shown that the impact damage area of the specimen with 30° helix angle is smallest among the four types of biomimetic specimens. The periodic helical structure of mineralized collagen fibers in osteon can effectively improve the impact resistance of cortical bone. The research results can provide useful guidance for the design and manufacture of high-performance, impact-resistant biomimetic composite materials.

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