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1.
Sheng Li Xue Bao ; 75(4): 487-496, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37583035

RESUMO

It is well established that increased excitability of the presympathetic neurons in the hypothalamic paraventricular nucleus (PVN) during hypertension leads to heightened sympathetic outflow and hypertension. However, the mechanism underlying the overactivation of PVN presympathetic neurons remains unclear. This study aimed to investigate the role of endogenous corticotropin-releasing factor (CRF) on the excitability of presympathetic neurons in PVN using Western blot, arterial blood pressure (ABP) and renal sympathetic nerve activity (RSNA) recording, CRISPR/Cas9 technique and patch-clamp technique. The results showed that CRF protein expression in PVN was significantly upregulated in spontaneously hypertensive rats (SHRs) compared with normotensive Wistar-Kyoto (WKY) rats. Besides, PVN administration of exogenous CRF significantly increased RSNA, heart rate and ABP in WKY rats. In contrast, knockdown of upregulated CRF in PVN of SHRs inhibited CRF expression, led to membrane potential hyperpolarization, and decreased the frequency of current-evoked firings of PVN presympathetic neurons, which were reversed by incubation of exogenous CRF. Perfusion of rat brain slices with artificial cerebrospinal fluid containing CRF receptor 1 (CRFR1) blocker, NBI-35965, or CRF receptor 2 (CRFR2) blocker, Antisauvagine-30, showed that blocking CRFR1, but not CRFR2, hyperpolarized the membrane potential and inhibited the current-evoked firing of PVN presympathetic neurons in SHRs. However, blocking CRFR1 or CRFR2 did not affect the membrane potential and current-evoked firing of presympathetic neurons in WKY rats. Overall, these findings indicate that increased endogenous CRF release from PVN CRF neurons enhances the excitability of presympathetic neurons via activation of CRFR1 in SHRs.


Assuntos
Hipertensão , Núcleo Hipotalâmico Paraventricular , Ratos , Animais , Ratos Endogâmicos SHR , Núcleo Hipotalâmico Paraventricular/fisiologia , Receptores de Hormônio Liberador da Corticotropina/genética , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Ratos Endogâmicos WKY , Hormônio Liberador da Corticotropina/farmacologia , Hormônio Liberador da Corticotropina/metabolismo , Neurônios/fisiologia , Sistema Nervoso Simpático
2.
J Phys Chem Lett ; 13(29): 6831-6838, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35857895

RESUMO

We study the influence of a linear energy bias on a nonequilibrium excitation on a chain of molecules coupled to local vibrations (a tilted Holstein model) using both a random-walk rate kernel theory and a nonperturbative, massively parallelized adaptive-basis algorithm. We uncover structured and discrete vibronic resonance behavior fundamentally different from both linear response theory and homogeneous polaron dynamics. Remarkably, resonance between the phonon energy ℏω and the bias δϵ occurs not only at integer but also fractional ratios δϵ/(ℏω) = m/n, which effect long-range n-bond m-phonon tunneling. These observations are reproduced in a model calculation of a recently demonstrated Cy3 system, and the effect of dipole-dipole-type non-nearest-neighbor coupling and vibrationally relaxed initial states is also considered. Potential applications range from molecular electronics to optical lattices and artificial light harvesting via vibronic engineering of coherent quantum transport.

3.
J Phys Chem Lett ; 12(39): 9531-9538, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34569800

RESUMO

The electromagnetic field in an optical cavity can dramatically modify and even control chemical reactivity via vibrational strong coupling (VSC). Since the typical vibration and cavity frequencies are considerably larger than thermal energy, it is essential to adopt a quantum description of cavity-catalyzed adiabatic chemical reactions. Using quantum transition state theory (TST), we examine the coherent nature of adiabatic reactions in cavities and derive the cavity-induced changes in eigenfrequencies, zero-point energy, and quantum tunneling. The resulting quantum TST calculation allows us to explain and predict the resonance effect (i.e., maximal kinetic modification via tuning the cavity frequency), collective effect (i.e., linear scaling with the molecular density), and selectivity (i.e., cavity-induced control of the branching ratio). The TST calculation is further supported by perturbative analysis of polariton normal modes, which not only provides physical insights to cavity-catalyzed chemical reactions but also presents a general approach to treat other VSC phenomena.

4.
J Phys Chem Lett ; 11(17): 7204-7211, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32787319

RESUMO

The question of how quantum coherence facilitates energy transfer has been intensively debated in the scientific community. Since natural and artificial light-harvesting units operate under the stationary condition, we address this question via a nonequilibrium steady-state analysis of a molecular dimer irradiated by incoherent sunlight and then generalize the key predictions to arbitrarily complex exciton networks. The central result of the steady-state analysis is the coherence-flux-efficiency relation: η = c∑i≠jFijκj = 2c∑i≠jJijIm[ρij]κj, where c is the normalization constant. In this relation, the first equality indicates that the energy transfer efficiency, η, is uniquely determined by the trapping flux, which is the product of the flux, F, and branching ratio, κ, for trapping at the reaction centers, and the second equality indicates that the energy transfer flux, F, is equivalent to the quantum coherence measured by the imaginary part of the off-diagonal density matrix, that is, Fij = 2JijIm[ρij]. Consequently, maximal steady-state coherence gives rise to optimal efficiency. The coherence-flux-efficiency relation holds rigorously and generally for any exciton network of arbitrary connectivity under the stationary condition and is not limited to incoherent radiation or incoherent pumping. For light-harvesting systems under incoherent light, the nonequilibrium energy transfer flux (i.e., steady-state coherence) is driven by the breakdown of detailed balance and by the quantum interference of light excitations and leads to the optimization of energy transfer efficiency. It should be noted that the steady-state coherence or, equivalently, efficiency is the combined result of light-induced transient coherence, inhomogeneous depletion, and the system-bath correlation and is thus not necessarily correlated with quantum beatings. These findings are generally applicable to quantum networks and have implications for quantum optics and devices.

5.
J Nurs Res ; 26(2): 104-111, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29023255

RESUMO

BACKGROUND: Type 1 diabetes (T1D) is more prevalent in adolescents than in adults, and the self-management of insulin-dependent diabetes is complex. T1D requires injections of insulin, self-management of blood testing, regular physical activity, and diet monitoring, which are challenging for growing and developing adolescents. Adolescents are often more concerned with how they are perceived by their peers than how they perceive themselves. Positive peer responses influence the self-care management of adolescents with T1D in school settings. By contrast, negative peer responses and avoidance behaviors threaten to negatively affect the health outcomes of adolescents with T1D. Evidence indicates that peer influence is crucial to the successful self-management of diabetes in adolescents. However, very few studies have investigated the effect of peer influence on adolescents with T1D. PURPOSE: This article describes how adolescents with T1D perceive the responses of their peers to their diabetes self-management in school settings. METHODS: Ten 12- to 17-year-old adolescents with diabetes were recruited from a pediatric endocrinology clinic at a university hospital in Taiwan. Audio-recorded interview data were transcribed verbatim and reviewed for accuracy. A thematic analysis approach was used to analyze the narrative content of semistructured interviews with participants. The rigor of the data collection and analysis was emphasized. RESULTS: Analysis of peer responses to the diabetes care practices of the participants revealed six themes: knowledge seeking, curiosity, enthusiasm, empathy, fearfulness, and isolation and bullying. Subthemes were categorized to illustrate how adolescents with T1D balance the challenge of diabetes self-care regimens and normal peer interactions. They were coping with the requirements of their T1D regimen and hoping to determine the perceptions of their peers toward this regimen and themselves. CONCLUSIONS/IMPLICATIONS FOR PRACTICE: Understanding the perception of peer identity for adolescents with T1D provides information for diabetes education and assists school nurses to facilitate successful T1D management in adolescents.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Grupo Associado , Autogestão/psicologia , Percepção Social , Adolescente , Criança , Feminino , Humanos , Masculino , Pesquisa Qualitativa , Taiwan
6.
Sci Rep ; 6: 34804, 2016 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-27713556

RESUMO

We investigate the decoherence dynamics of continuous variable entanglement as the system-environment coupling strength varies from the weak-coupling to the strong-coupling regimes. Due to the existence of localized modes in the strong-coupling regime, the system cannot approach equilibrium with its environment, which induces a nonequilibrium quantum phase transition. We analytically solve the entanglement decoherence dynamics for an arbitrary spectral density. The nonequilibrium quantum phase transition is demonstrated as the system-environment coupling strength varies for all the Ohmic-type spectral densities. The 3-D entanglement quantum phase diagram is obtained.

7.
PLoS One ; 10(2): e0117067, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25647296

RESUMO

XopDXcc8004, a type III effector of Xanthomonas campestris pv. campestris (Xcc) 8004, is considered a shorter version of the XopD, which lacks the N-terminal domain. To understand the functions of XopDXcc8004, in planta, a transgenic approach combined with inducible promoter to analyze the effects of XopDXcc8004 in Arabidopsis was done. Here, the expression of XopDXcc8004, in Arabidopsis elicited the accumulation of host defense-response genes. These molecular changes were dependent on salicylic acid and correlated with lesion-mimic phenotypes observed in XVE::XopDXcc8004 transgenic plants. Moreover, XopDXcc8004 was able to desumoylate HFR1, a basic helix-loop-helix transcription factor involved in photomorphogenesis, through SUMO protease activity. Interestingly, the hfr1-201 mutant increased the expression of host defense-response genes and displayed a resistance phenotype to Xcc8004. These data suggest that HFR1 is involved in plant innate immunity and is potentially regulated by XopDXcc8004.


Assuntos
Proteínas de Arabidopsis/imunologia , Arabidopsis/genética , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/imunologia , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Patógeno , Proteínas Nucleares/imunologia , Doenças das Plantas/genética , Xanthomonas campestris/fisiologia , Arabidopsis/imunologia , Arabidopsis/microbiologia , Proteínas de Arabidopsis/genética , Proteínas de Bactérias/imunologia , Proteínas de Ligação a DNA/genética , Mutação , Proteínas Nucleares/genética , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/imunologia , Ácido Salicílico/imunologia , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/imunologia
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