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1.
Nature ; 572(7769): 363-367, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31341282

RESUMO

Quantum computers can efficiently solve classically intractable problems, such as the factorization of a large number1 and the simulation of quantum many-body systems2,3. Universal quantum computation can be simplified by decomposing circuits into single- and two-qubit entangling gates4, but such decomposition is not necessarily efficient. It has been suggested that polynomial or exponential speedups can be obtained with global N-qubit (N greater than two) entangling gates5-9. Such global gates involve all-to-all connectivity, which emerges among trapped-ion qubits when using laser-driven collective motional modes10-14, and have been implemented for a single motional mode15,16. However, the single-mode approach is difficult to scale up because isolating single modes becomes challenging as the number of ions increases in a single crystal, and multi-mode schemes are scalable17,18 but limited to pairwise gates19-23. Here we propose and implement a scalable scheme for realizing global entangling gates on multiple 171Yb+ ion qubits by coupling to multiple motional modes through modulated laser fields. Because such global gates require decoupling multiple modes and balancing all pairwise coupling strengths during the gate, we develop a system with fully independent control capability on each ion14. To demonstrate the usefulness and flexibility of these global gates, we generate a Greenberger-Horne-Zeilinger state with up to four qubits using a single global operation. Our approach realizes global entangling gates as scalable building blocks for universal quantum computation, motivating future research in scalable global methods for quantum information processing.

2.
J Physiol ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953534

RESUMO

The central histaminergic system has a pivotal role in emotional regulation and psychiatric disorders, including anxiety, depression and schizophrenia. However, the effect of histamine on neuronal activity of the centrolateral amygdala (CeL), an essential node for fear and anxiety processing, remains unknown. Here, using immunostaining and whole-cell patch clamp recording combined with optogenetic manipulation of histaminergic terminals in CeL slices prepared from histidine decarboxylase (HDC)-Cre rats, we show that histamine selectively suppresses excitatory synaptic transmissions, including glutamatergic transmission from the basolateral amygdala, on both PKC-δ- and SOM-positive CeL neurons. The histamine-induced effect is mediated by H3 receptors expressed on VGLUT1-/VGLUT2-positive presynaptic terminals in CeL. Furthermore, optoactivation of histaminergic afferent terminals from the hypothalamic tuberomammillary nucleus (TMN) also significantly suppresses glutamatergic transmissions in CeL via H3 receptors. Histamine neither modulates inhibitory synaptic transmission by presynaptic H3 receptors nor directly excites CeL neurons by postsynaptic H1, H2 or H4 receptors. These results suggest that histaminergic afferent inputs and presynaptic H3 heteroreceptors may hold a critical position in balancing excitatory and inhibitory synaptic transmissions in CeL by selective modulation of glutamatergic drive, which may not only account for the pathophysiology of psychiatric disorders but also provide potential psychotherapeutic targets. KEY POINTS: Histamine selectively suppresses the excitatory, rather than inhibitory, synaptic transmissions on both PKC-δ- and SOM-positive neurons in the centrolateral amygdala (CeL). H3 receptors expressed on VGLUT1- or VGLUT2-positive afferent terminals mediate the suppression of histamine on glutamatergic synaptic transmission in CeL. Optogenetic activation of hypothalamic tuberomammillary nucleus (TMN)-CeL histaminergic projections inhibits glutamatergic transmission in CeL via H3 receptors.

3.
Int J Mol Sci ; 25(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38397008

RESUMO

Although more than 30 different types of neuropeptides have been identified in various cell types and circuits of the cerebellum, their unique functions in the cerebellum remain poorly understood. Given the nature of their diffuse distribution, peptidergic systems are generally assumed to exert a modulatory effect on the cerebellum via adaptively tuning neuronal excitability, synaptic transmission, and synaptic plasticity within cerebellar circuits. Moreover, cerebellar neuropeptides have also been revealed to be involved in the neurogenetic and developmental regulation of the developing cerebellum, including survival, migration, differentiation, and maturation of the Purkinje cells and granule cells in the cerebellar cortex. On the other hand, cerebellar neuropeptides hold a critical position in the pathophysiology and pathogenesis of many cerebellar-related motor and psychiatric disorders, such as cerebellar ataxias and autism. Over the past two decades, a growing body of evidence has indicated neuropeptides as potential therapeutic targets to ameliorate these diseases effectively. Therefore, this review focuses on eight cerebellar neuropeptides that have attracted more attention in recent years and have significant potential for clinical application associated with neurodegenerative and/or neuropsychiatric disorders, including brain-derived neurotrophic factor, corticotropin-releasing factor, angiotensin II, neuropeptide Y, orexin, thyrotropin-releasing hormone, oxytocin, and secretin, which may provide novel insights and a framework for our understanding of cerebellar-related disorders and have implications for novel treatments targeting neuropeptide systems.


Assuntos
Doenças Cerebelares , Neuropeptídeos , Humanos , Cerebelo/metabolismo , Células de Purkinje/metabolismo , Neurônios/metabolismo , Córtex Cerebelar/metabolismo , Neuropeptídeos/metabolismo , Doenças Cerebelares/patologia
4.
Chembiochem ; 24(22): e202300391, 2023 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-37718314

RESUMO

We report a fluorescent dye TM by incorporating the tetraphenylethylene (TPE) and cholesterol components into perylene bisimides (PBI) derivative. Fluorescence emission spectrum shows that the dye has stable red emission and aggregation-induced emission (AIE) characteristics. The incorporation of cholesterol components triggers TM to show induced chirality through supramolecular self-assembly. The cRGD-functionalized nanoparticles were prepared by encapsulating fluorescent dyes with amphiphilic polymer matrix. The functionalized fluorescent organic nanoparticles exhibit excellent biocompatibility, large Stokes' shift and good photostability, which make them effective fluorescent probes for targeting cancer cells with high fluorescence contrast.


Assuntos
Nanopartículas , Neoplasias , Corantes Fluorescentes/farmacologia , Polímeros , Diagnóstico por Imagem , Colesterol , Neoplasias/diagnóstico por imagem
5.
Cerebellum ; 22(5): 888-904, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36040660

RESUMO

The classical motor center cerebellum is one of the most consistent structures of abnormality in autism spectrum disorders (ASD), and neuropeptide oxytocin is increasingly explored as a potential pharmacotherapy for ASD. However, whether oxytocin targets the cerebellum for therapeutic effects remains unclear. Here, we report a localization of oxytocin receptor (OXTR) in Purkinje cells (PCs) of cerebellar lobule Crus I, which is functionally connected with ASD-implicated circuits. OXTR activation neither affects firing activities, intrinsic excitability, and synaptic transmission of normal PCs nor improves abnormal intrinsic excitability and synaptic transmission of PCs in maternal immune activation (MIA) mouse model of autism. Furthermore, blockage of OXTR in Crus I in wild-type mice does not induce autistic-like social, stereotypic, cognitive, and anxiety-like behaviors. These results suggest that oxytocin signaling in Crus I PCs seems to be uninvolved in ASD pathophysiology, and contribute to understanding of targets and mechanisms of oxytocin in ASD treatment.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Camundongos , Animais , Receptores de Ocitocina , Ocitocina , Células de Purkinje
6.
Pharmacol Res ; 191: 106773, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37068531

RESUMO

Specific medications to combat cerebellar ataxias, a group of debilitating movement disorders characterized by difficulty with walking, balance and coordination, are still lacking. Notably, cerebellar microglial activation appears to be a common feature in different types of ataxic patients and rodent models. However, direct evidence that cerebellar microglial activation in vivo is sufficient to induce ataxia is still lacking. Here, by employing chemogenetic approaches to manipulate cerebellar microglia selectively and directly, we found that specific chemogenetic activation of microglia in the cerebellar vermis directly leads to ataxia symptoms in wild-type mice and aggravated ataxic motor deficits in 3-acetylpyridine (3-AP) mice, a classic mouse model of cerebellar ataxia. Mechanistically, cerebellar microglial proinflammatory activation induced by either chemogenetic M3D(Gq) stimulation or 3-AP modeling hyperexcites Purkinje cells (PCs), which consequently triggers ataxia. Blockade of microglia-derived TNF-α, one of the most important proinflammatory cytokines, attenuates the hyperactivity of PCs driven by microglia. Moreover, chemogenetic inhibition of cerebellar microglial activation or suppression of cerebellar microglial activation by PLX3397 and minocycline reduces the production of proinflammatory cytokines, including TNF-α, to effectively restore the overactivation of PCs and alleviate motor deficits in 3-AP mice. These results suggest that cerebellar microglial activation may aggravate the neuroinflammatory response and subsequently induce dysfunction of PCs, which in turn triggers ataxic motor deficits. Our findings thus reveal a causal relationship between proinflammatory activation of cerebellar microglia and ataxic motor symptoms, which may offer novel evidence for therapeutic intervention for cerebellar ataxias by targeting microglia and microglia-derived inflammatory mediators.


Assuntos
Ataxia Cerebelar , Camundongos , Animais , Ataxia Cerebelar/induzido quimicamente , Células de Purkinje/fisiologia , Microglia , Fator de Necrose Tumoral alfa/farmacologia , Cerebelo , Citocinas
7.
Proc Natl Acad Sci U S A ; 117(50): 32155-32164, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33257584

RESUMO

Anxiety commonly co-occurs with obsessive-compulsive disorder (OCD). Both of them are closely related to stress. However, the shared neurobiological substrates and therapeutic targets remain unclear. Here we report an amelioration of both anxiety and OCD via the histamine presynaptic H3 heteroreceptor on glutamatergic afferent terminals from the prelimbic prefrontal cortex (PrL) to the nucleus accumbens (NAc) core, a vital node in the limbic loop. The NAc core receives direct hypothalamic histaminergic projections, and optogenetic activation of hypothalamic NAc core histaminergic afferents selectively suppresses glutamatergic rather than GABAergic synaptic transmission in the NAc core via the H3 receptor and thus produces an anxiolytic effect and improves anxiety- and obsessive-compulsive-like behaviors induced by restraint stress. Although the H3 receptor is expressed in glutamatergic afferent terminals from the PrL, basolateral amygdala (BLA), and ventral hippocampus (vHipp), rather than the thalamus, only the PrL- and not BLA- and vHipp-NAc core glutamatergic pathways among the glutamatergic afferent inputs to the NAc core is responsible for co-occurrence of anxiety- and obsessive-compulsive-like behaviors. Furthermore, activation of the H3 receptor ameliorates anxiety and obsessive-compulsive-like behaviors induced by optogenetic excitation of the PrL-NAc glutamatergic afferents. These results demonstrate a common mechanism regulating anxiety- and obsessive-compulsive-like behaviors and provide insight into the clinical treatment strategy for OCD with comorbid anxiety by targeting the histamine H3 receptor in the NAc core.


Assuntos
Transtornos de Ansiedade/tratamento farmacológico , Agonistas dos Receptores Histamínicos/administração & dosagem , Núcleo Accumbens/fisiopatologia , Transtorno Obsessivo-Compulsivo/tratamento farmacológico , Receptores Histamínicos H3/metabolismo , Vias Aferentes/efeitos dos fármacos , Vias Aferentes/fisiopatologia , Animais , Transtornos de Ansiedade/etiologia , Transtornos de Ansiedade/fisiopatologia , Transtornos de Ansiedade/psicologia , Modelos Animais de Doenças , Glutamatos/metabolismo , Histamina/metabolismo , Antagonistas dos Receptores Histamínicos H3/administração & dosagem , Humanos , Região Hipotalâmica Lateral/efeitos dos fármacos , Região Hipotalâmica Lateral/fisiopatologia , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Núcleo Accumbens/citologia , Núcleo Accumbens/efeitos dos fármacos , Transtorno Obsessivo-Compulsivo/etiologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Transtorno Obsessivo-Compulsivo/psicologia , Optogenética , Técnicas de Patch-Clamp , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiopatologia , Terminações Pré-Sinápticas/efeitos dos fármacos , Terminações Pré-Sinápticas/metabolismo , Ratos , Ratos Transgênicos , Técnicas Estereotáxicas , Estresse Psicológico/complicações , Estresse Psicológico/psicologia , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
8.
J Radiol Prot ; 43(1)2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36649650

RESUMO

The neutron dose resulting from external irradiation can be evaluated by measuring the counts of characteristicγrays produced by24Na in the human body. The detection geometry with the highest detection efficiency for measuring the whole-body24Na activity has not been studied. In this work, the MCNP code is used to calculate the spatial distribution of24Na in the human body irradiated by neutrons with different energies in different irradiation geometries. The fluence distribution of24Na characteristicγrays on the body surface is calculated. The counts of24Na characteristicγrays induced by monochromatic neutron irradiation are simulated to fit the scenarios of neutron irradiation by a continuous energy spectrum neutron. When the spontaneous neutrons from252Cf with 1Gy dose irradiate the human body, (3.63-4.35) × 1010 24Na atoms are produced. The lower detection limit for the neutron absorption dose is reduced from ∼100 to less than 1 mGy when the radiation detector is placed over the back of the human body close to the liver. The relative error between the measured counts of24Na characteristic γ rays caused by252Cf neutron irradiation and the counts fitted by monochromatic neutron irradiation data is less than 5.7%. The neutron dose received from a continuous energy spectrum neutron can be acquired quickly and accurately by weighted summing of the data for monochromatic neutron irradiations calculated in this paper, which is more convenient and practical than the previous method.


Assuntos
Corpo Humano , Nêutrons , Humanos , Doses de Radiação
9.
Zhongguo Zhong Yao Za Zhi ; 48(9): 2368-2378, 2023 May.
Artigo em Chinês | MEDLINE | ID: mdl-37282866

RESUMO

This study aims to investigate the expression, prognosis, and clinical significance of C5orf46 in gastric cancer and to study the interaction between the active components of C5orf46 and tarditional Chinese medicine. The ggplot2 package was utilized for differential expression analysis of C5orf46 in gastric cancer tissues and normal tissues. The survival package was used for survival analysis, univariate regression analysis, and multivariate regression analysis. Nomogram analysis was used to assess the connection between C5orf46 expression in gastric cancer and overall survival. The abundance of tumor-infiltrating lymphocytes was calculated by GSVA package. Coremine database, Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP) database, and PubChem database were used to search the potential components corresponding to C5orf46 gene and tarditional Chinese medicine. Molecular docking was performed to explore the binding affinity of potential components to C5orf46. Cell experiments were performed to explore the expression of C5orf46 gene in cells of the blank group, model group, and drug administration groups. As compared with normal tissues, C5orf46 expression was higher in gastric cancer tissues, which had more significant predictive effects in the early stages(T2, N0, and M0). The more advanced the tumor node metastasis(TNM) stage, the higher the C5orf46 expression and the lower the probability of survival of patients with gastric cancer. The expression of C5orf46 positively correlated with the helper T cells1 in gastric cancer and the macrophage infiltration level in gastric cancer, and negatively correlated with B cells, central memory T cells, helper T cells 17, and follicular helper T cells. Seven potential components of C5orf46 were obtained, and three active components were obtained after the screening, which matched five tarditional Chinese medicines, namely, Sojae Semen Nigrum, Jujubae Fructus, Trichosanthis Fructus, Silybi Fructus, and Bambusae Concretio Silicea. Molecular docking revealed that sialic acid and adeno-sine monophosphate(AMP) had a good binding ability to C5orf46. The results of real-time quantitative polymerase chain reaction(RT-qPCR) and Western blot showed that, as compared with the model group, the mRNA and protein expression levels of C5orf46 were significantly lower in the drug administration groups. The lowest expression level was found at the concentration of 40 µmol·L~(-1). The results of this study provide ideas for the clinical development of traditional Chinese medicine compounds for the treatment of gastric cancer as well as other cancers.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Medicina Tradicional Chinesa , Simulação de Acoplamento Molecular , Prognóstico , Biologia Computacional
10.
Zhongguo Zhong Yao Za Zhi ; 48(6): 1535-1545, 2023 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-37005841

RESUMO

To compare the pancreatic proteomics and autophagy between Rehmanniae Radix-and Rehmanniae Radix Praeparata-treated mice with type 2 diabetes mellitus(T2DM). The T2DM mouse model was established by high-fat diet coupled with streptozotocin(STZ, intraperitoneal injection, 100 mg·kg~(-1), once a day for three consecutive days). The mice were then randomly assigned into a control group, low-(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix groups, low-(150 mg·kg~(-1)) and high-dose(300 mg·kg~(-1)) catalpol groups, low-(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix Praeparata groups, low-(150 mg·kg~(-1)) and high-dose(300 mg·kg~(-1)) 5-hydroxymethyl furfuraldehyde(5-HMF) groups, and a metformin(250 mg·kg~(-1)) group. In addition, a normal group was also set and each group included 8 mice. The pancreas was collected after four weeks of administration and proteomics tools were employed to study the effects of Rehmanniae Radix and Rehmanniae Radix Praeparata on protein expression in the pancreas of T2DM mice. The expression levels of proteins involved in autophagy, inflammation, and oxidative stress response in the pancreatic tissues of T2DM mice were determined by western blotting, immunohistochemical assay, and transmission electron microscopy. The results showed that the differential proteins between the model group and Rehmanniae Radix/Rehmanniae Radix Prae-parata group were enriched in 7 KEGG pathways, such as autophagy-animal, which indicated that the 7 pathways may be associated with T2DM. Compared with the control group, drug administration significantly up-regulated the expression levels of beclin1 and phosphorylated mammalian target of rapamycin(p-mTOR)/mTOR and down-regulated those of the inflammation indicators, Toll-like receptor-4(TLR4) and Nod-like receptor protein 3(NLRP3), in the pancreas of T2DM mice, and Rehmanniae Radix showed better performance. In addition, the expression levels of inducible nitric oxide synthase(iNOS), nuclear factor erythroid 2-related factor 2(Nrf2), and heine oxygenase-1(HO-1) in the pancreas of T2DM mice were down-regulated after drug administration, and Rehmanniae Radix Praeparata demonstrated better performance. The results indicate that both Rehmanniae Radix and Rehmanniae Radix Praeparata can alleviate the inflammatory symptoms, reduce oxidative stress response, and increase the autophagy level in the pancreas of T2DM mice, while they exert the effect on different autophagy pathways.


Assuntos
Diabetes Mellitus Tipo 2 , Camundongos , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Estreptozocina/farmacologia , Dieta Hiperlipídica/efeitos adversos , Proteômica , Inflamação , Serina-Treonina Quinases TOR , Autofagia , Mamíferos
11.
Lab Invest ; 102(3): 245-252, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34819630

RESUMO

Breast fibroepithelial lesions (FEL) are biphasic tumors which consist of benign fibroadenomas (FAs) and the rarer phyllodes tumors (PTs). FAs and PTs have overlapping features, but have different clinical management, which makes correct core biopsy diagnosis important. This study used whole-slide images (WSIs) of 187 FA and 100 PT core biopsies, to investigate the potential role of artificial intelligence (AI) in FEL diagnosis. A total of 9228 FA patches and 6443 PT patches was generated from WSIs of the training subset, with each patch being 224 × 224 pixel in size. Our model employed a two-stage architecture comprising a convolutional neural network (CNN) component for feature extraction from the patches, and a recurrent neural network (RNN) component for whole-slide classification using activation values from the global average pooling layer in the CNN model. It achieved an overall slide-level accuracy of 87.5%, with accuracies of 80% and 95% for FA and PT slides respectively. This affirms the potential role of AI in diagnostic discrimination between FA and PT on core biopsies which may be further refined for use in routine practice.


Assuntos
Inteligência Artificial , Biópsia com Agulha de Grande Calibre/métodos , Neoplasias da Mama/patologia , Mama/patologia , Fibroadenoma/patologia , Tumor Filoide/patologia , Diagnóstico Diferencial , Feminino , Fibroadenoma/diagnóstico , Humanos , Redes Neurais de Computação , Tumor Filoide/diagnóstico , Curva ROC
12.
Sheng Li Xue Bao ; 74(2): 135-144, 2022 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-35503061

RESUMO

Vestibular compensation is an important model for developing the prevention and intervention strategies of vestibular disorders, and investigating the plasticity of the adult central nervous system induced by peripheral injury. Medial vestibular nucleus (MVN) in brainstem is critical center for vestibular compensation. Its neuronal excitability and sensitivity have been implicated in normal function of vestibular system. Previous studies mainly focused on the changes in neuronal excitability of the MVN in lesional side of the rat model of vestibular compensation following the unilateral labyrinthectomy (UL). However, the plasticity of sensitivity of bilateral MVN neurons dynamically responding to input stimuli is still largely unknown. In the present study, by using qPCR, whole-cell patch clamp recording in acute brain slices and behavioral techniques, we observed that 6 h after UL, rats showed a significant deficit in spontaneous locomotion, and a decrease in excitability of type B neurons in the ipsilesional rather than contralesional MVN. By contrast, type B neurons in the contralesional rather than ipsilesional MVN exhibited an increase in response sensitivity to the ramp and step input current stimuli. One week after UL, both the neuronal excitability of the ipsilesional MVN and the neuronal sensitivity of the contralesional MVN recovered to the baseline, accompanied by a compensation of spontaneous locomotion. In addition, the data showed that the small conductance Ca2+-activated K+ (SK) channel involved in the regulation of type B MVN neuronal sensitivity, showed a selective decrease in expression in the contralesional MVN 6 h after UL, and returned to normal level 1 week later. Pharmacological blockage of SK channel in contralateral MVN to inhibit the UL-induced functional plasticity of SK channel significantly delayed the compensation of vestibular motor dysfunction. These results suggest that the changes in plasticity of the ipsilesional MVN neuronal excitability, together with changes in the contralesional MVN neuronal sensitivity, may both contribute to the development of vestibular symptoms as well as vestibular compensation, and SK channel may be an essential ionic mechanism responsible for the dynamic changes of MVN neuronal sensitivity during vestibular compensation.


Assuntos
Núcleos Vestibulares , Vestíbulo do Labirinto , Animais , Locomoção , Neurônios/fisiologia , Técnicas de Patch-Clamp , Ratos , Núcleos Vestibulares/metabolismo
13.
J Neurosci ; 40(29): 5531-5548, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32487697

RESUMO

3-Phosphoinositide-dependent protein kinase-1 (PDK1) plays a critical role in the development of mammalian brain. Here, we investigated the role of PDK1 in Purkinje cells (PCs) by generating the PDK1-conditional knock-out mice (cKO) through crossing PV-cre or Pcp2-cre mice with Pdk1fl/fl mice. The male mice were used in the behavioral testing, and the other experiments were performed on mice of both sexes. These PDK1-cKO mice displayed decreased cerebellar size and impaired motor balance and coordination. By the electrophysiological recording, we observed the reduced spontaneous firing of PCs from the cerebellar slices of the PDK1-cKO mice. Moreover, the cell body size of PCs in the PDK1-cKO mice was time dependently reduced compared with that in the control mice. And the morphologic complexity of PCs was also decreased after PDK1 deletion. These effects may have contributed to the reduction of the rpS6 (reduced ribosomal protein S6) phosphorylation and the PKCγ expression in PDK1-cKO mice since the upregulation of pS6 by treatment of 3-benzyl-5-((2-nitrophenoxy) methyl)-dihydrofuran-2(3H)-1, the agonist of mTOR1, partly rescued the reduction in the cell body size of the PCs, and the delivery of recombinant adeno-associated virus-PKCγ through cerebellar injection rescued the reduced complexity of the dendritic arbor in PDK1-cKO mice. Together, our data suggest that PDK1, by regulating rpS6 phosphorylation and PKCγ expression, controls the cell body maintenance and the dendritic development in PCs and is critical for cerebellar motor coordination.SIGNIFICANCE STATEMENT Here, we show the role of 3-phosphoinositide-dependent protein kinase-1 (PDK1) in Purkinje cells (PCs). The ablation of PDK1 in PCs resulted in a reduction of cell body size, and dendritic complexity and abnormal spontaneous firing, which attributes to the motor defects in PDK1-conditional knock-out (cKO) mice. Moreover, the ribosomal protein S6 (rpS6) phosphorylation and the expression of PKCγ are downregulated after the ablation of PDK1. Additionally, upregulation of rpS6 phosphorylation by3-benzyl-5-((2-nitrophenoxy) methyl)-dihydrofuran-2(3H)-1 partly rescued the reduction in cell body size of PCs, and the overexpression of PKCγ in PDK1-KO PCs rescued the reduction in the dendritic complexity. These findings indicate that PDK1 contributes to the maintenance of the cell body and the dendritic development of PCs by regulating rpS6 phosphorylation and PKCγ expression.


Assuntos
Corpo Celular/fisiologia , Cerebelo/fisiologia , Dendritos/fisiologia , Células de Purkinje/fisiologia , Piruvato Desidrogenase Quinase de Transferência de Acetil/fisiologia , Transdução de Sinais , Potenciais de Ação , Animais , Comportamento Animal , Cerebelo/citologia , Cerebelo/crescimento & desenvolvimento , Feminino , Masculino , Camundongos , Camundongos Knockout , Proteína Quinase C/metabolismo , Células de Purkinje/citologia , Piruvato Desidrogenase Quinase de Transferência de Acetil/genética , Proteína S6 Ribossômica/metabolismo , Serina-Treonina Quinases TOR/metabolismo
14.
Analyst ; 146(24): 7450-7463, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34788777

RESUMO

Fluorescent probes along with fluorescence microscopy are essential tools for biomedical research. Various cellular ubiquitous chemical factors such as pH, H2O2, and Ca2+ are labeled and traced using specific fluorescent probes, therefore helping us to explore their physiological function and pathological change. Among them, intracellular pH value is an important factor that governs biological processes, generally ∼7.2. Furthermore, specific organelles within cells possess unique acid-base homeostasis, involving the acidic lysosomes, alkalescent mitochondria, and neutral endoplasmic reticulum and Golgi apparatus, which undergo various physiological processes such as intracellular digestion, ATP production, and protein folding and processing. In this review, recently reported fluorescent probes targeted toward the lysosomes, mitochondria, endoplasmic reticulum, Golgi apparatus, and cytoplasm for sensing pH change are discussed, which involves molecular structures, fluorescence behavior, and biological applications.


Assuntos
Corantes Fluorescentes , Peróxido de Hidrogênio , Retículo Endoplasmático , Concentração de Íons de Hidrogênio , Lisossomos
15.
J Neurosci ; 39(3): 420-433, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30413645

RESUMO

Vestibular compensation is responsible for the spontaneous recovery of postural, locomotor, and oculomotor dysfunctions in patients with peripheral vestibular lesion or posterior circulation stroke. Mechanism investigation of vestibular compensation is of great importance in both facilitating recovery of vestibular function and understanding the postlesion functional plasticity in the adult CNS. Here, we report that postsynaptic histamine H1 receptor contributes greatly to facilitating vestibular compensation. The expression of H1 receptor is restrictedly increased in the ipsilesional rather than contralesional GABAergic projection neurons in the medial vestibular nucleus (MVN), one of the most important centers for vestibular compensation, in unilateral labyrinthectomized male rats. Furthermore, H1 receptor mediates an asymmetric excitation of the commissural GABAergic but not glutamatergic neurons in the ipsilesional MVN, which may help to rebalance bilateral vestibular systems and promote vestibular compensation. Selective blockage of H1 receptor in the MVN significantly retards the recovery of both static and dynamic vestibular symptoms following unilateral labyrinthectomy, and remarkably attenuates the facilitation of betahistine, whose effect has traditionally been attributed to its antagonistic action on the presynaptic H3 receptor, on vestibular compensation. These results reveal a previously unknown role for histamine H1 receptor in vestibular compensation and amelioration of vestibular motor deficits, as well as an involvement of H1 receptor in potential therapeutic effects of betahistine. The findings provide not only a new insight into the postlesion neuronal circuit plasticity and functional recovery in the CNS, but also a novel potential therapeutic target for vestibular disorders.SIGNIFICANCE STATEMENT Vestibular disorders manifest postural imbalance, nystagmus, and vertigo. Vestibular compensation is critical for facilitating recovery from vestibular disorders, and of great importance in understanding the postlesion functional plasticity in the adult CNS. Here, we show that postsynaptic H1 receptor in the medial vestibular nucleus (MVN) contributes greatly to the recovery of both static and dynamic symptoms following unilateral vestibular lesion. H1 receptor selectively mediates the asymmetric activation of commissural inhibitory system in the ipsilesional MVN and actively promotes vestibular compensation. The findings provide not only a new insight into the postlesion neuronal circuit plasticity and functional recovery of CNS, but also a novel potential therapeutic target for promoting vestibular compensation and ameliorating vestibular disorders.


Assuntos
Receptores Histamínicos H1/efeitos dos fármacos , Vestíbulo do Labirinto/fisiopatologia , Animais , beta-Histina/uso terapêutico , Orelha Interna , Lateralidade Funcional/efeitos dos fármacos , Antagonistas dos Receptores Histamínicos H1/farmacologia , Antagonistas dos Receptores Histamínicos H3/uso terapêutico , Locomoção/efeitos dos fármacos , Masculino , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/fisiopatologia , Neurônios/efeitos dos fármacos , Nistagmo Fisiológico/efeitos dos fármacos , Técnicas de Patch-Clamp , Equilíbrio Postural/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Doenças Vestibulares/tratamento farmacológico , Núcleos Vestibulares/citologia , Núcleos Vestibulares/efeitos dos fármacos , Núcleos Vestibulares/fisiopatologia , Ácido gama-Aminobutírico
17.
Brain Behav Immun ; 89: 400-413, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32717406

RESUMO

Ataxia, characterized by uncoordinated movement, is often found in patients with cerebellar hemorrhage (CH), leading to long-term disability without effective management. Microglia are among the first responders to CNS insult. Yet the role and mechanism of microglia in cerebellar injury and ataxia after CH are still unknown. Using Ki20227, an inhibitor for colony-stimulating factor 1 receptor which mediates the signaling responsible for the survival of microglia, we determined the impact of microglial depletion on cerebellar injury and ataxia in a murine model of CH. Microglial depletion reduced cerebellar lesion volume and alleviated gait abnormality, motor incoordination, and locomotor dysfunction after CH. Suppression of CH-initiated microglial activation with minocycline ameliorated cerebellum infiltration of monocytes/macrophages, as well as production of proinflammatory cytokines and chemokine C-C motif ligand-2 (CCL-2) that recruits monocytes/macrophages. Furthermore, both minocycline and bindarit, a CCL-2 inhibitor, prevented apoptosis and electrophysiological dysfunction of Purkinje cells, the principal neurons and sole outputs of the cerebellar cortex, and consequently improved ataxia-like motor abnormalities. Our findings suggest a detrimental role of microglia in neuroinflammation and ataxic motor symptoms after CH, and pave a new path to understand the neuroimmune mechanism underlying CH-induced cerebellar ataxia.


Assuntos
Lesões Encefálicas , Ataxia Cerebelar , Animais , Ataxia , Ataxia Cerebelar/tratamento farmacológico , Humanos , Camundongos , Microglia , Monócitos
18.
Mol Psychiatry ; 24(2): 282-293, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30087452

RESUMO

Hypothalamic neuropeptide orexin has been implicated in the pathophysiology of psychiatric disorders and accumulating clinical evidence indicates a potential link between orexin and depression. However, the exact role of orexin in depression, particularly the underlying neural substrates and mechanisms, remains unknown. In this study, we reveal a direct projection from the hypothalamic orexinergic neurons to the ventral pallidum (VP), a structure that receives an increasing attention for its critical position in rewarding processing, stress responses, and depression. We find that orexin directly excites GABAergic VP neurons and prevents depressive-like behaviors in rats. Two orexin receptors, OX1R and OX2R, and their downstream Na+-Ca2+ exchanger and L-type Ca2+ channel co-mediate the effect of orexin. Furthermore, pharmacological blockade or genetic knockdown of orexin receptors in VP increases depressive-like behaviors in forced swim test and sucrose preference test. Intriguingly, blockage of orexinergic inputs in VP has no impact on social proximity in social interaction test between novel partners, but remarkably strengthens social avoidance under an acute psychosocial stress triggered by social rank. Notably, a significantly increased orexin level in VP is accompanied by an increase in serum corticosterone in animals exposed to acute stresses, including forced swimming, food/water deprivation and social rank stress, rather than non-stress situations. These results suggest that endogenous orexinergic modulation on VP is especially critical for protecting against depressive reactions to stressful events. The findings define an indispensable role for the central orexinergic system in preventing depression by promoting stress resilience.


Assuntos
Depressão/tratamento farmacológico , Orexinas/metabolismo , Orexinas/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Depressão/fisiopatologia , Modelos Animais de Doenças , Neurônios GABAérgicos/metabolismo , Hipotálamo/metabolismo , Masculino , Neuropeptídeos/metabolismo , Receptores de Orexina/metabolismo , Receptores de Orexina/fisiologia , Ratos , Ratos Sprague-Dawley , Comportamento Social , Estresse Psicológico/metabolismo
19.
J Radiol Prot ; 40(1): 270-279, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31887728

RESUMO

When responding to nuclear and radiological emergencies, rapid and on-site detections of possible internal radioactive contaminants are required for early dose estimation and medical triage. Nasal swab analysis is an effective method to provide valuable information for early and fast estimates of alpha radionuclide inhalation intakes and resultant doses. In this study, to improve the quality of nasal swab measurements, a specialised double-detector alpha counter was designed. Various parameters including swab materials, sample pre-preparation, angle-dependence and vacuum dependence were investigated to optimise the reliability and convenience of the nasal swab method. An improved procedure of direct nasal swab measurement was eventually established, which could be used to obtain early data for initial dose assessment during the first response of nuclear and radiological emergencies.


Assuntos
Poluentes Radioativos do Ar/análise , Bioensaio/instrumentação , Exposição por Inalação/análise , Cavidade Nasal/química , Monitoramento de Radiação/instrumentação , Partículas alfa , Carga Corporal (Radioterapia) , Humanos , Liberação Nociva de Radioativos , Triagem
20.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(1): 80-85, 2020 Feb 28.
Artigo em Chinês | MEDLINE | ID: mdl-32131944

RESUMO

Objective To investigate the value of contrast-enhanced ultrasound(CEUS)quantitative parameters in the diagnosis of thyroid benign and malignant nodules. Methods The CEUS features of 85 histopathologically confirmed thyroid nodules were quantitatively analyzed using five parameters including rising time(RT),time to peak(TTP),area under the curve(AUC),maximum intensity(Imax),and mean transit time(mTT).The dynamic vascular pattern(DVP)curves were also drawn. Results The Imax(Z=-7.08,P=0.01)and AUC(Z=-2.03,P=0.04)of thyroid malignant nodules were significantly smaller than those of thyroid tissue,and the Imax(Z=-1.35,P=0.02)and AUC(Z=-0.21,P=0.02)of thyroid benign nodules were significantly larger than those of thyroid tissue.There were significant differences between thyroid benign and malignant nodules in Imax(Z=-4.16,P=0.00),AUC(Z=-3.01,P=0.01),and DVP curve types(P=0.00).RT(Z=-0.28,P=0.62),TTP(Z=-0.10,P=0.89),and mTT(Z=-0.79,P=0.05)were not significantly different between thyroid benign and malignant nodules. Conclusion The quantitative parameters of CEUS,especially Imax and AUC parameters,are valuable in the diagnosis of benign and malignant thyroid nodules.


Assuntos
Neoplasias da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/diagnóstico por imagem , Ultrassonografia , Meios de Contraste , Diagnóstico Diferencial , Humanos , Glândula Tireoide/diagnóstico por imagem
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