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1.
Biochem Biophys Res Commun ; 710: 149863, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38579535

RESUMO

Vascular calcification is an important factor in the high morbidity and mortality of Cardiovascular and cerebrovascular diseases. Vascular damage caused by calcification of the intima or media impairs the physiological function of the vascular wall. Inflammation is a central factor in the development of vascular calcification. Macrophages are the main inflammatory cells. Dynamic changes of macrophages with different phenotypes play an important role in the occurrence, progression and stability of calcification. This review focuses on macrophage polarization and the relationship between macrophages of different phenotypes and calcification environment, as well as the mechanism of interaction, it is considered that macrophages can promote vascular calcification by releasing inflammatory mediators and promoting the osteogenic transdifferentiation of smooth muscle cells and so on. In addition, several therapeutic strategies aimed at macrophage polarization for vascular calcification are described, which are of great significance for targeted treatment of vascular calcification.


Assuntos
Músculo Liso Vascular , Calcificação Vascular , Humanos , Calcificação Vascular/genética , Macrófagos , Osteogênese , Fenótipo , Miócitos de Músculo Liso
2.
Rev Cardiovasc Med ; 25(6): 227, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39076332

RESUMO

Background: Tai Chi is an increasingly utilized aerobic rehabilitation exercise in the field of cardiovascular disease (CVD). However, there remains debate regarding its effects on physiological function and mental health in patients with coronary heart disease (CHD). This study aims to investigate the impact of Tai Chi-based rehabilitation exercises on physical and psychological health outcomes for CHD patients. Methods: By collecting data from 12 databases up to December 2022, we conducted a meta-analysis of randomized controlled trials (RCTs) to evaluate the effects of Tai Chi on the physical function and psychological health among CHD patients. Results: We analyzed twenty qualified studies involving 2095 patients. Meta-analyses revealed that compared with conventional therapy groups, those who participated in Tai Chi-based interventions demonstrated significant improvements in physical function as measured by six-minute walk test (6MWT) [mean difference (MD) = 56.40, 95% confidence interval (CI) (38.50, 74.29), p < 0.01], maximal oxygen consumption ( VO 2 max) [standardized mean difference (SMD) = 0. 57, 95% CI (0.12, 1.03), p = 0.01], New York Heart Association (NYHA) class [relative risk (RR) = 1.34, 95% CI (1.18, 1.53), p < 0.01] and physical health components (PHC) [SMD = 1.23, 95% CI (0.76, 1.69), p < 0.01]. Additionally, Tai Chi participants showed greater improvement than control groups across various psychological parameters including anxiety scales [SMD = -0.80, 95% CI (-1.33, -0.28), p = 0.003], depression scales [SMD = -0.77, 95% CI (-1.32, -0.23), p = 0.005] and mental health components (MHC) [SMD = 1.27, 95% CI (0.76, -1.78), p < 0.01]. The GRADEpro (Grade Guideline Development Tool) indicated evidence levels ranging from very low to moderate. Conclusions: The present meta-analysis demonstrates that mind-body rehabilitation exercises based on Tai Chi can improve both physical and psychological health outcomes for CHD patients. These findings suggest that this exercise pattern may be a potential option for cardiovascular rehabilitation. PROSPERO Registration: The protocol for this systematic review and meta-analysis has been registered with PROSPERO International Prospective Systematic Reviews (No: CRD42022370021, http://www.crd.york.ac.uk/PROSPERO).

3.
BMC Cardiovasc Disord ; 24(1): 360, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39009987

RESUMO

BACKGROUND: The atherogenic index of plasma (AIP) is considered an independent risk factor for coronary artery disease (CAD). The present study investigated whether AIP correlates with the formation of coronary collateral circulation (CCC) in CAD patients with chronic total occlusion (CTO). METHODS: This retrospective study included 1093 CAD patients with CTO confirmed by coronary angiography from January 2020 to December 2020 at Beijing Anzhen Hospital. Based on the Rentrop scoring system, the patients were divided into the good CCC group and the poor CCC group. AIP was calculated by log (triglyceride/high-density lipoprotein cholesterol). Meanwhile, the study population was further divided into four groups according to the quartiles of AIP. RESULTS: Patients in the poor CCC group exhibited significantly higher AIP compared to those in the good CCC group (0.31 ± 0.27 vs. 0.14 ± 0.24, p < 0.001). Multivariate logistic regression analysis revealed an independent association between AIP and poor CCC, regardless of whether AIP was treated as a continuous or categorical variable (p < 0.001), after adjusting for confounding factors. Besides, this association remained consistent across most subgroups. The incorporation of AIP into the baseline model significantly enhanced the accuracy of identifying poor CCC [area under the curve (AUC): baseline model, 0.661 vs. baseline model + AIP, 0.721, p for comparison < 0.001]. CONCLUSIONS: Elevated AIP is independently associated with an increased risk of poor CCC in CAD patients with CTO, and AIP may improve the ability to identify poor CCC in clinical practice.


Assuntos
Biomarcadores , Circulação Colateral , Angiografia Coronária , Circulação Coronária , Oclusão Coronária , Humanos , Masculino , Oclusão Coronária/fisiopatologia , Oclusão Coronária/diagnóstico por imagem , Oclusão Coronária/sangue , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Doença Crônica , Biomarcadores/sangue , Medição de Risco , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Valor Preditivo dos Testes , Triglicerídeos/sangue , HDL-Colesterol/sangue , Fatores de Risco , Prognóstico
4.
Cardiovasc Diabetol ; 22(1): 286, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891647

RESUMO

BACKGROUND: The triglyceride-glucose (TyG) index, which is a reliable substitute indicator for insulin resistance, has been considered an independent risk factor for long-term outcomes in patients with cardiovascular disease. However, it remains unknown whether the TyG index is associated with poor prognosis in acute coronary syndrome (ACS) patients with prior coronary artery bypass grafting (CABG) undergoing percutaneous coronary intervention (PCI). METHODS: A total of 1158 ACS patients with prior CABG undergoing PCI were retrospectively studied. The TyG index was calculated by ln[fasting triglyceride (mg/dL) × fasting blood glucose (mg/dL)/2]. The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE), a composite of all-cause death, nonfatal myocardial infarction, nonfatal stroke, and unplanned repeat revascularization. RESULTS: During a median of 42-month follow-up, 350 patients (30.2%) experienced at least one endpoint event. Based on the optimal cut-off value of the TyG index, patients were divided into the high TyG index group and the low TyG index group. Patients in the high TyG index group had higher risks of MACCE (35.3% vs. 25.3%, p < 0.001), major adverse cardiovascular events (MACE) (31.1% vs. 23.4%, p = 0.003), nonfatal stroke (4.2% vs. 1.9%, p = 0.022) and unplanned repeat revascularization (19.4% vs. 11.3%, p < 0.001) than those in the low TyG index group. Cox regression analysis demonstrated that there was an independent association between the TyG index and MACCE regardless of whether the TyG index was a continuous or categorical variable (HR 1.42, 95% CI 1.09-1.86, p = 0.009; HR 1.53, 95% CI 1.16-2.01, p = 0.003, respectively). Restricted cubic spline curve exhibited that the relationship between the TyG index and MACCE was linear (p for non-linear = 0.595, p for overall = 0.005). By incorporating the TyG index groups into baseline risk model, the accuracy of predicting MACCE was improved [AUC: baseline risk model, 0.618 vs. baseline risk model + TyG index groups, 0.636, p for comparison = 0.042]. CONCLUSIONS: The TyG index is independently associated with MACCE, suggesting that the TyG index may serve as a valid indicator for predicting poor prognosis in ACS patients with prior CABG undergoing PCI.


Assuntos
Síndrome Coronariana Aguda , Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Acidente Vascular Cerebral , Humanos , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/cirurgia , Glucose , Intervenção Coronária Percutânea/efeitos adversos , Triglicerídeos , Estudos Retrospectivos , Ponte de Artéria Coronária/efeitos adversos , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/etiologia , Prognóstico , Doença da Artéria Coronariana/etiologia
5.
Brief Bioinform ; 21(4): 1455-1464, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31157825

RESUMO

Depression is a seriously disabling psychiatric disorder with a significant burden of disease. Metabolic abnormalities have been widely reported in depressed patients and animal models. However, there are few systematic efforts that integrate meaningful biological insights from these studies. Herein, available metabolic knowledge in the context of depression was integrated to provide a systematic and panoramic view of metabolic characterization. After screening more than 10 000 citations from five electronic literature databases and five metabolomics databases, we manually curated 5675 metabolite entries from 464 studies, including human, rat, mouse and non-human primate, to develop a new metabolite-disease association database, called MENDA (http://menda.cqmu.edu.cn:8080/index.php). The standardized data extraction process was used for data collection, a multi-faceted annotation scheme was developed, and a user-friendly search engine and web interface were integrated for database access. To facilitate data analysis and interpretation based on MENDA, we also proposed a systematic analytical framework, including data integration and biological function analysis. Case studies were provided that identified the consistently altered metabolites using the vote-counting method, and that captured the underlying molecular mechanism using pathway and network analyses. Collectively, we provided a comprehensive curation of metabolic characterization in depression. Our model of a specific psychiatry disorder may be replicated to study other complex diseases.


Assuntos
Biologia Computacional/métodos , Sistemas de Gerenciamento de Base de Dados , Depressão/metabolismo , Metabolômica , Animais , Humanos , Modelos Animais
6.
Opt Express ; 28(23): 35350-35362, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33182983

RESUMO

We study the correlated evolutions of two far-spaced Rydberg atomic pairs with different resonant frequencies, interacting via van der Waals (vdW) potentials and driven by a common laser field. They are found to exhibit in-phase (anti-phase) beating dynamics characterized by identical (complementary) intra-pair entanglements under a specific condition in regard of inter-pair vdW potentials and driving field detunings. This occurs when each atomic pair just oscillates between its ground state and symmetric entangled state because its doubly excited state and asymmetric entangled state are forbidden due to rigid dipole blockade and perfect destructive interference, respectively. More importantly, optimal inter-pair overall entanglement can be attained at each beating node corresponding to semi-optimal intra-pair entanglements, and inevitable dissipation processes just result in a slow decay of intra-pair and inter-pair entanglements yet without destroying in-phase and anti-phase beating dynamics.

7.
Opt Express ; 26(9): 12330-12343, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29716144

RESUMO

We study the optical response of a double optomechanical cavity system assisted by two Rydberg atoms. The target atom is only coupled with one side cavity by a single cavity mode, and gate one is outside the cavities. It has been realized that a long-range manipulation of optical properties of a hybrid system, by controlling the Rydberg atom decoupled with the optomechanical cavity. Switching on the coupling between atoms and cavity mode, the original spatial inversion symmetry of the double cavity structure has been broken. Combining the controllable optical non-reciprocity with the coherent perfect absorption/transmission/synthesis effect (CPA/CPT/CPS reported by [ X.-B.Yan Opt. Express 22, 4886 (2014)], we put forward the theoretical schemes of an all-optical transistor which contains functions such as a controllable diode, rectifier, and amplifier by controlling a single gate photon.

8.
Opt Lett ; 42(21): 4283-4286, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29088143

RESUMO

Cold atoms trapped in one-dimensional optical lattices and driven to the four-level N configuration are exploited for achieving an electromagnetically induced grating with parity-time-symmetry. This nontrivial grating exhibits unidirectional diffraction patterns, e.g., with incident probe photons diffracted into either negative or positive angles, depending on the sign relation between spatially modulated absorption and dispersion coefficients. Such asymmetric light diffraction is a result of the out-of-phase interplay of amplitude and phase modulations of transmission function and can be easily tuned via optical depth, probe detuning, pump Rabi frequencies, etc.

9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 34(3): 449-455, 2017 Jun 01.
Artigo em Chinês | MEDLINE | ID: mdl-29745513

RESUMO

Skin aging is the most intuitive and obvious sign of the human aging processes. Qualitative and quantitative determination of skin aging is of particular importance for the evaluation of human aging and anti-aging treatment effects. To solve the problem of subjectivity of conventional skin aging grading methods, the self-organizing map (SOM) network was used to explore an automatic method for skin aging grading. First, the ventral forearm skin images were obtained by a portable digital microscope and two texture parameters, i.e., mean width of skin furrows and the number of intersections were extracted by image processing algorithm. Then, the values of texture parameters were taken as inputs of SOM network to train the network. The experimental results showed that the network achieved an overall accuracy of 80.8%, compared with the aging grading results by human graders. The designed method appeared to be rapid and objective, which can be used for quantitative analysis of skin images, and automatic assessment of skin aging grading.

10.
Cells ; 13(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38607002

RESUMO

(1) Background: Spermatozoa acquired motility and matured in epididymis after production in the testis. However, there is still limited understanding of the specific characteristics of sperm development across different species. In this study, we employed a comprehensive approach to analyze cell compositions in both testicular and epididymal tissues, providing valuable insights into the changes occurring during meiosis and spermiogenesis in mouse and pig models. Additionally, we identified distinct gene expression signatures associated with various spermatogenic cell types. (2) Methods: To investigate the differences in spermatogenesis between mice and pigs, we constructed a single-cell RNA dataset. (3) Results: Our findings revealed notable differences in testicular cell clusters between these two species. Furthermore, distinct gene expression patterns were observed among epithelial cells from different regions of the epididymis. Interestingly, regional gene expression patterns were also identified within principal cell clusters of the mouse epididymis. Moreover, through analysing differentially expressed genes related to the epididymis in both mouse and pig models, we successfully identified potential marker genes associated with sperm development and maturation for each species studied. (4) Conclusions: This research presented a comprehensive single-cell landscape analysis of both testicular and epididymal tissues, shedding light on the intricate processes involved in spermatogenesis and sperm maturation, specifically within mouse and pig models.


Assuntos
Sêmen , Testículo , Camundongos , Masculino , Animais , Suínos , Testículo/metabolismo , Espermatozoides/metabolismo , Epididimo/metabolismo , Espermatogênese/genética
11.
Int Urol Nephrol ; 55(7): 1837-1846, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36781680

RESUMO

BACKGROUND: Renal interstitial fibrosis (RIF) seriously threatens the health of individuals. MiRNAs regulate the progression of fibrosis. Nevertheless, the detailed function of miR-449a in RIF is largely unknown. METHODS: In vitro and in vivo models of RIF were developed to evaluate the function of miR-449a. The relationship among miR-449a, KLF4, and MFN2 was explored using a dual-luciferase reporter assay and chromatin immunoprecipitation. Additionally, the pathological changes in the mice were detected using Masson staining. The mRNA and protein expressions were assessed using quantitative reverse transcription polymerase chain reaction and western blot, respectively. RESULTS: TGF-ß1 downregulated the expressions of KLF4 and MFN2 in TCMK-1 cells, but upregulated the level of miR-449a. The downregulation of miR-449a significantly inhibited TGF-ß1-induced upregulation of fibrotic proteins in TCMK-1 cells. Meanwhile, miR-449a directly targeted KLF4. Moreover, KLF4 overexpression activated MFN2 transcription and reversed TGF-ß1-induced fibrosis by positively regulating MFN2. Furthermore, the downregulation of miR-449a could obviously alleviate the symptoms of RIF in mice with unilateral ureteral obstruction. CONCLUSION: MiR-449a downregulation attenuated the development of RIF by mediating the KLF4/MFN2 axis. Therefore, miR-449a might act as a target in treating RIF.


Assuntos
Nefropatias , MicroRNAs , Animais , Camundongos , Regulação para Baixo , Fibrose , Nefropatias/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Fator de Crescimento Transformador beta1/metabolismo
12.
Intensive Crit Care Nurs ; 75: 103349, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36464604

RESUMO

BACKGROUND: Sleep disturbance is a common complaint among critically ill patients in intensive care units and after hospitalisation. However, the prevalence of sleep disturbance among critically ill patients varies widely. OBJECTIVE: To estimate the prevalence of sleep disturbance among critically ill patients in the intensive care unit and after hospitalisation. METHODS: Electronic databases were searched from their inception until 15 August 2022. Only observational studies with cross-sectional, prospective, and retrospective designs investigating sleep disturbance prevalence among critically ill adults (aged ≥ 18 years) during intensive care unit stay and after hospitalisation were included. RESULTS: We found 13 studies investigating sleep disturbance prevalence in intensive care units and 14 investigating sleep disturbance prevalence after hospitalisation, with 1,228 and 3,065 participants, respectively. The prevalence of sleep disturbance during an ICU stay was 66 %, and at two, three, six and ≥ 12 months after hospitalisation was 64 %, 49 %, 40 %, and 28 %, respectively. Studies using the Richards-Campbell Sleep Questionnaire detected a higher prevalence of sleep disturbance among patients in intensive care units than non-intensive care unit specific questionnaires; studies reported comparable sleep disturbance prevalence during intensive care stays for patients with and without mechanical ventilation. CONCLUSION: Sleep disturbance is prevalent in critically ill patients admitted to an intensive care unit and persists for up to one year after hospitalisation, with prevalence ranging from 28 % to 66 %. The study results highlight the importance of implementing effective interventions as early as possible to improve intensive care unit sleep quality.


Assuntos
Estado Terminal , Transtornos do Sono-Vigília , Adulto , Humanos , Estudos Prospectivos , Estado Terminal/epidemiologia , Estudos Retrospectivos , Estudos Transversais , Prevalência , Hospitalização , Unidades de Terapia Intensiva , Sono , Transtornos do Sono-Vigília/epidemiologia
13.
Eur J Med Chem ; 224: 113673, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34303872

RESUMO

Rare oncogenic NTRK gene fusions result in uncontrolled TRK signaling leading to various adult and pediatric solid tumors. Based on the architecture of our multi-targeted clinical candidate BPR1K871 (10), we designed and synthesized a series of quinazoline compounds as selective and orally bioavailable type II TRK inhibitors. Property-driven and lead optimization strategies informed by structure-activity relationship studies led to the identification of 39, which showed higher (about 15-fold) selectivity for TRKA over AURA and AURB, as well as potent cellular activity (IC50 = 56.4 nM) against the KM12 human colorectal cancer cell line. 39 also displayed good AUC and oral bioavailability (F = 27%), excellent in vivo efficacy (TGI = 64%) in a KM12 xenograft model, and broad-spectrum anti-TRK mutant potency (IC50 = 3.74-151.4 nM), especially in the double-mutant TRKA enzymatic assays. 39 is therefore proposed for further development as a next-generation, selective, and orally-administered type II TRK inhibitor.


Assuntos
Desenho de Fármacos , Inibidores de Proteínas Quinases/química , Receptor trkA/antagonistas & inibidores , Administração Oral , Animais , Aurora Quinase A/antagonistas & inibidores , Aurora Quinase A/metabolismo , Aurora Quinase B/antagonistas & inibidores , Aurora Quinase B/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Meia-Vida , Humanos , Camundongos , Camundongos Nus , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Ratos , Receptor trkA/metabolismo , Relação Estrutura-Atividade , Transplante Heterólogo
14.
Front Psychol ; 11: 581908, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329237

RESUMO

The topics of serious leisure and subjective well-being have been discussed extensively in previous research. It is generally acknowledged that people prefer to experience deeper satisfaction and happiness through serious participation in leisure-time physical activities. However, it is essential to examine the relationship between serious leisure and subjective well-being in an urban setting as well as the mediating effect of leisure satisfaction. Data were collected from 447 recreational runners at the 2018 Wuxi International Marathon event in China. The study results showed that serious leisure was positively associated with leisure satisfaction and subjective well-being, that leisure satisfaction was positively associated with subjective well-being, and that leisure satisfaction completely mediated the relationship between serious leisure and subjective well-being. Running group membership significantly affected the path from serious leisure to leisure satisfaction, while other demographic variables (e.g., gender and education) did not moderate any paths. These results help explain the intricate relationship between serious leisure and subjective well-being and offer theoretical and managerial implications for serious leisure.

15.
Environ Technol ; 40(2): 210-218, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28942703

RESUMO

The objective of this study was to evaluate the anaerobic degradation of sulfamethoxazole (SMX) and the associated bacterial community changes in swine and sewage sludges. The degradation rate of SMX was higher in swine sludge than in sewage sludge. The addition of lactate, citrate, and sucrose had significant effects on SMX degradation, and sucrose addition yielded a higher SMX degradation rate than the other additives. At concentrations of 0.1-10 g/l sucrose, the SMX degradation rates increased in the sludge. The bacterial genera from swine sludge with sucrose exhibited the highest SMX degrading efficiency. Seventeen bacterial genera were found to be the major bacterial community members involved in SMX degradation in the sludge.


Assuntos
Esgotos , Sulfametoxazol , Anaerobiose , Animais , Bactérias , Suínos
16.
Sci Rep ; 9(1): 1722, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30742060

RESUMO

Accurate evaluation of individual risk of intravenous immunoglobin (IVIG)-resistance is critical for adopting regimens for the first treatment and prevention of coronary artery lesions (CALs) in patients with Kawasaki disease (KD). METHODS: The KD patients hospitalized in Chongqing Children's Hospital, in west China, from October 2007 to December 2017 were retrospectively reviewed. Data were collected and compared between IVIG-resistant group and IVIG-responsive group. The independent risk factors were determined using multivariate regression analysis. A new prediction model was built and compared with the previous models. RESULTS: A total of 5277 subjects were studied and eight independent risk factors were identified including higher red blood cell distribution width (RDW), lower platelet count (PLT), lower percentage of lymphocyte (P-LYM), higher total bile acid (TBA), lower albumin, lower serum sodium level, higher degree of CALs (D-CALs) and younger age. The new predictive model showed an AUC of 0.74, sensitivity of 76% and specificity of 59%. For individual's risk probability of IVIG-resistance, an equation was given. CONCLUSIONS: IVIG-resistance could be predicted by RDW, PLT, P-LYM, TBA, albumin, serum sodium level, D-CALs and age. The new model appeared to be superior to those previous models for KD population in Chongqing city.


Assuntos
Resistência a Medicamentos , Imunoglobulinas Intravenosas/uso terapêutico , Modelos Teóricos , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Biomarcadores , China/epidemiologia , Humanos , Imunoglobulinas Intravenosas/administração & dosagem , Imunoglobulinas Intravenosas/efeitos adversos , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Razão de Chances , Prognóstico , Curva ROC , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
17.
Sci Rep ; 8(1): 2933, 2018 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-29440729

RESUMO

We study the parity-time (PT) symmetry characteristics and the applications to nonlinear optics in an optical trimer system consisting of two indirectly coupled standing-mode micro-cavities and a two-level quantum emitter (QE) placed at the intersection of two cavities. We find this trimer system can exhibit analogical phenomena as those in typical [Formula: see text]-symmetric dimer systems composed of a passive cavity directly coupled to an active cavity. This system, whose [Formula: see text] symmetry is demonstrated by our analytic results, can be transformed between the [Formula: see text]-symmetric phase and the [Formula: see text]-broken phase by adjusting relevant system parameters. Then, with this system, we observe both the linear and nonlinear parts of the transmission field become remarkably enhanced and can further reach peak values around the [Formula: see text] breaking point. In addition, we show the negative correlation between the gain degree of the linear (nonlinear) transmission part and decay rate of the QE. This trimer proposal is feasible for experiments and may provide a promising platform for [Formula: see text]-symmetric optics of low-light levels. Moreover, novel phenomena arising from the QE-cavity-coupling induced nonlinearity gain could be explored to fabricate photonic devices and controllable nonlinear optical media for quantum information process and communication of photons.

18.
Semin Thorac Cardiovasc Surg ; 30(3): 327-335, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29551744

RESUMO

The primary objectives of this study were to describe the characteristics and survival outcomes for children supported with the HeartWare HVAD® system from the global community. This was a retrospective survey of patients <18 years of age with an HVAD® system. Questionnaires were sent to sites worldwide in April 2015 and collected between May 2015 and 2016. Information on 205 patients was collected. The median age at implantation was 13.1 years (interquartile range [IQR] 9.8-15.8 years) and the weight was 42 kg (IQR 28-60 kg). Over half of the implants occurred in males (61%), with the most common diagnosis being cardiomyopathy (n = 168, 82%). The majority of HVAD® systems implanted were left ventricular assist device (n = 189, 92.2%). Temporary right ventricular support was utilized in 24 patients (12%) with a median duration of 12 days (6-32 days). Fifty-five percent (n = 111) of the patients were discharged home after implantation after a median (IQR) duration of hospital stay of 40 days (28-71 days). By 12 months, the proportion of patients who underwent heart transplant was 65.4%, 10.7% had died, 3.2% were explanted for recovery, and 20.8% remained on the device. Death on the device on multivariable analysis was associated with the need for temporary RV support (hazard ratio [HR] 10.65 (95% CI 12.53-44.81), P = 0.001) and pump exchange (HR 7.9 (95% CI 1.8-34.2], P = 0.006). The use of the HeartWare HVAD system in the pediatric population is associated with mortality with the majority of patients supported to heart transplant by 1 year post implant. These positive results are independent of geographic location. The need for a temporary right heart support and pump exchange is associated with a higher risk of poor outcomes, and further work is required to predict these patients to allow for optimization. Although survival results are promising, further studies are needed to delineate the associated morbidities with this technology in the pediatric population.


Assuntos
Insuficiência Cardíaca/terapia , Coração Auxiliar , Adolescente , Fatores Etários , Criança , Remoção de Dispositivo , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Transplante de Coração , Humanos , Masculino , Desenho de Prótese , Falha de Prótese , Recuperação de Função Fisiológica , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Função Ventricular Esquerda , Função Ventricular Direita
19.
Sci Rep ; 7(1): 15834, 2017 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-29158548

RESUMO

We study the synchronization behaviors of two indirectly coupled mechanical oscillators of different frequencies in a doublecavity optomechanical system. It is found that quantum synchronization is roughly vanishing though classical synchronization seems rather good when each cavity mode is driven by an external field in the absence of temporal modulations. By periodically modulating cavity detunings or driving amplitudes, however, it is possible to observe greatly enhanced quantum synchronization accompanied with nearly perfect classical synchronization. The level of quantum synchronization observed here is, in particular, much higher than that for two directly coupled mechanical oscillators. Note also that the modulation on cavity detunings is more appealing than that on driving amplitudes when the robustness of quantum synchronization is examined against the bath's mean temperature or the oscillators' frequency difference.

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