Nonreciprocal magnon blockade via the Barnett effect.

We propose a scheme to achieve nonreciprocal magnon blockade via the Barnett effect in a magnon-based hybrid system. Due to the rotating yttrium iron garnet (YIG) sphere, the Barnett shift induced by the Barnett effect can be tuned from positive to negative via controlling magnetic field direction, leading to nonreciprocity. We show that a nonreciprocal unconventional magnon blockade (UMB) can emerge only from one magnetic field direction but not from the other side. Particularly, by further tuning system parameters, we simultaneously observe a nonreciprocal conventional magnon blockade (CMB) and a nonreciprocal UMB. This result achieves a switch between efficiency (UMB) and purity (CMB) of a single-magnon blockade. Interestingly, stronger UMB can be reached under stronger qubit-magnon coupling, even the strong coupling regime. Moreover, the nonreciprocity of the magnon blockade is sensitive to temperature. This work opens up a way for achieving quantum nonreciprocal magnetic devices and chiral magnon communications.

Nonreciprocal sideband responses in a spinning microwave magnomechanical system.

Nonreciprocal sideband responses in a spinning microwave magnomechanical system consists of a spinning resonator coupled with a yttrium iron garnet sphere are proposed. We show that the efficiency of sideband generation can be enhanced in one driving direction but restrained in the opposite. This nonreciprocity results from Sagnac effect induced by the spinning resonator, leading to asymmetric magnonic responses in two different driving directions. Beyond the conventional linearized description, the properties of nonreciprocal two-color second-order sideband are demonstrated. By adjusting Sagnac-Fizeau shift and the power of control field, the degree of asymmetric magnonic responses can be strengthened, therefore causing stronger nonreciprocity of sideband. Especially, for the case of strong Sagnac-Fizeau shift and the control field, high level of efficiency and isolation ratio of sideband are achieved simultaneously and the operational bandwidth of strong nonreciprocity can be expanded. Our proposal provides an effective avenue for the manipulation of the nonreciprocity of sideband and has potentially practical applications in on-chip microwave isolation devices and magnon-based precision measurement.

Parametric-amplification-induced nonreciprocal magnon laser.

We theoretically propose a scheme to achieve all-optical nonreciprocal magnon lasing action in a composite cavity optomagnonical system considering of a yttrium iron garnet sphere coupled to a parametric resonator. The magnon lasing behavior can be engendered via the magnon-induced Brillouin scattering process in the cavity optomagnonical system. By unidirectionally driving the χ(2)-nonlinear resonator with a classical coherent field, the squeezed effect occurs only in the selected direction due to the phase-matching condition, resulting in asymmetric detuning between the two resonators, which is the physical mechanism to generate a nonreciprocal magnon laser. We further examine the gain factor and power threshold of the magnon laser. Moreover, the isolation rate can reach 21 dB by adjusting the amplitude of the parametric amplification. Our work shows a path to obtain an all-optical nonreciprocal magnon laser, which provides a means for the preparation of a coherent magnon laser and laser protection.

Elevated TNIP3 mRNA Expression in TNF-α-Secreting Cells from Patients with Major Depressive Disorder.

OBJECTIVE: Elevated levels of pro-inflammatory cytokines, in particular tumor necrotic factor alpha (TNF-α), and abnormalities in negative regulation in Toll-like receptor (TLR) signaling pathways are associated with major depressive disorder (MDD). Previous research by our group disclosed lower expression of TNF-α-induced protein 3 (TNFAIP3), one of the negative regulators of the TLR4 signaling pathway, in depressive patients than in healthy controls. METHODS: In this study, we assessed the mRNA levels of TNFAIP3, TNFAIP3-interacting proteins (TNIP), including TNIP1, TNIP2, and TNIP3, and TNFAIP3-like proteins, such as cezanne1, cezanne2, trabid, and VCIP135, in TNF-α-secreting cells and examined their association with severity of depression using the 17-item Hamilton Depression Rating Scale (HAMD-17) scores from 30 MDD patients and 30 healthy controls. Twenty-six patients received a second assessment after treatment with antidepressants for 4 weeks. RESULTS: TNF-α-secreting cells displayed higher TNIP3 mRNA expression in MDD patients than in healthy controls before treatment, which was marginally decreased after antidepressant treatment. In addition, the TNIP2 level could be effectively applied to predict changes in HAMD scores after linear regression analysis. CONCLUSION: Our collective findings suggest that molecules associated with negative regulation of innate immunity are aberrantly expressed in patients with MDD and present potential therapeutic targets.

TNFAIP3 mRNA Level Is Associated with Psychological Anxiety in Major Depressive Disorder.

BACKGROUND: Major depressive disorder has been shown to be associated with inflammation and the dysregulation of innate immune responses. Previously, we showed an inverse correlation between the severity of depression and level of TNFAIP3 mRNA expression. The present study further evaluated the association between TNFAIP3 mRNA expression level and symptoms of major depressive disorder (MDD) in 91 patients (20 men and 71 women). METHODS: The relationships between subscores on the 17-item Hamilton Depression Rating Scale (HAMD-17) and TNFAIP3 mRNA levels were assessed by multiple linear regression. RESULTS: Only psychological anxiety on the HAMD-17 correlated significantly with TNFAIP3 mRNA expression. Other symptoms, such as depressed mood, insomnia, work and activities, and suicide, were not associated with TNFAIP3 mRNA expression. CONCLUSION: These findings suggest a significant association between anxiety and TNFAIP3 mRNA levels in patients with MDD.

Antidepressants normalize elevated Toll-like receptor profile in major depressive disorder.

RATIONALE: Abnormalities in Toll-like receptor (TLR) expression in depression have been inferred in part from observed increases in TLR4 levels in peripheral blood mononuclear cells (PBMCs) and postmortem brains of depressed and suicidal patients. Our previous study found differences in the TLR expression in PBMCs between healthy controls and patients with major depressive disorder. Normalization of increased TLR4 in PBMCs by cognitive behavior psychotherapy has been reported. However, the effects of antidepressants remain unknown. OBJECTIVES: Changes in TLR1-9 expression levels of PBMCs were examined in 56 patients with MDD. The 17-item Hamilton Depression Rating Scale (HAMD-17) and mRNA expression levels of TLRs were assessed in parallel with a housekeeping gene using qRT-PCR before and after treatment with antidepressants. RESULTS: TLR3, TLR4, TLR5, TLR7, TLR8, and TLR9 were expressed at elevated levels in patients with MDD and were significantly decreased by treatment with antidepressants for 4 weeks. Antidepressant treatment completely normalized TLR3, TLR5, TLR7, TLR8, and TLR9 levels, whereas TLR1, TLR2, TLR4, and TLR6 were decreased to below normal levels. A subgroup analysis found that only TLR3 was significantly higher at baseline in the nonremission group. In addition, a multiple linear regression analysis revealed that only low TLR3 before treatment predicted improvement in HAMD-17 scores. CONCLUSIONS: These findings suggest that antidepressant treatment exerts anti-inflammatory effects in patients with MDD and identify TLR profiles as a predictor of response to antidepressant therapy. Further studies investigating the effects of manipulating individual TLRs on depression are needed to fully elucidate the underlying mechanism.

Association between toll-like receptor 4 expression and symptoms of major depressive disorder.

BACKGROUND: In our previous study, toll-like receptor 4 (TLR4) mRNA expression level was associated with severity of major depressive disorder (MDD) evaluated with the 17-item Hamilton Depression Rating Scale (HAMD-17). However, there are few studies that have investigated the relationship between symptoms of MDD and changes in TLR4 expression. Therefore, the aim of the present study was to further analyze the association between subscales of HAMD-17 and TLR4. METHODS: Fifty-one patients with MDD (15 male and 36 female) participated in this study. HAMD-17 was used to assess the symptoms of major depression. The mRNA expression levels of TLR4 were examined in parallel with a housekeeping gene, using real-time polymerase chain reaction. A stepwise linear regression forward model was used to evaluate the relationships between items of HAMD-17 and TLR4 expression. RESULTS: Some sickness behavior-associated symptoms, including suicide, somatic symptoms of anxiety, or performance of work and activities, were not associated with TLR4 expression. However, psychological signs of anxiety and loss of weight in HAMD-17 can predict the expression level of TLR4. CONCLUSION: Our results suggest a significant association between anxiety, body weight loss, and TLR4 mRNA levels in patients with MDD. Larger longitudinal studies combining both subjective and objective measures of depression are needed to clarify the link between TLR4 and symptoms of depression.

Association between toll-like receptors expression and major depressive disorder.

Accumulating evidences suggest that Toll-like receptors (TLRs) were involved in the pathophysiology of major depressive disorder. TLR4 was thought to be associated with major depressive disorder in animal model, but the others were still unknown. In order to examine TLR1-9 mRNA expression levels in peripheral blood and their relationships with the psychopathology of major depressive disorder, 30 patients with major depressive disorder were compared with 29 healthy controls. The 17-item Hamilton Depression Rating Scale (HAMD-17) was used to assess the severity of major depression. The mRNA expression levels of TLRs were examined in parallel with a housekeeping gene using real-time polymerase chain reaction (RT-PCR). Analysis of covariance with age and body mass index adjustment revealed a significantly higher expression of TLR3, 4, 5 and 7 mRNA but lower expression of TLR1 and 6 in patients with major depressive disorder as compared with healthy controls. Multiple linear regression analysis revealed that TLR4 was an independent risk factor relating to severity of major depression. These findings suggest that TLRs, especially TLR4, may be involved in the psychopathology of major depression.

From random coil polymers to helical structures induced by carbon nanotubes and supramolecular interactions.

A simple method is reported for the preparation of double-helical structures through a series of achiral random and block copolymers poly(styrene-co-4-vinylbenzyl triazolylmethyl methylthymine) (PS-co-PVBT) with various T units on the side chains through click reactions of poly(styrene-co-4-vinylbenzyl azide) (PS-co-PVBN(3)) with propargyl thymine (PT) and also the synthesis of the A-appended pyrene derivative (A-Py) through click chemistry. This double-helical structure is observed from achiral random-coil polystyrene (PS) main chains, stabilized through the combination of multiple A-T hydrogen bonds, and π-π stacking between pyrene units and single-walled carbon nanotubes (SWCNTs).