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1.
Chemistry ; 30(13): e202303917, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38093171

RESUMO

Aqueous zinc-ion batteries (ZIBs) have emerged as the most promising candidate for large-scale energy storage due to their inherent safety, environmental friendliness, and cost-effectiveness. Simultaneously, the utilization of organic electrode materials with renewable resources, environmental compatibility, and diverse structures has sparked a surge in research and development of aqueous Zn-organic batteries (ZOBs). A comprehensive review is warranted to systematically present recent advancements in design principles, synthesis techniques, energy storage mechanisms, and zinc-ion storage performance of organic cathodes. In this review article, we comprehensively summarize the energy storage mechanisms employed by aqueous ZOBs. Subsequently, we categorize organic cathode materials into small-molecule compounds and high-molecular polymers respectively. Novel polymer materials such as conjugated polymers (CPs), conjugated microporous polymers (CMPs), and covalent organic frameworks (COFs) are highlighted with an overview of molecular design strategies and structural optimization based on organic cathode materials aimed at enhancing the performance of aqueous ZOBs. Finally, we discuss the challenges faced by aqueous ZOBs along with future prospects to offer insights into their practical applications.

2.
Opt Express ; 31(15): 24492-24504, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37475275

RESUMO

Previous studies have shown that split-ring resonators (SRRs) can be utilized to achieve finely tuned nearest-neighbor coupling strengths in various one-dimensional hopping models. In our study, we present a systematic investigation of resonator coupling, providing a comprehensive quantitative description of the interaction between SRRs and complementary split-ring resonators (CSRRs) for any orientation combination. Our method includes an estimation of the coupling strength through a linear combination of periodic functions based on two orientation angles, with a sinusoidal expansion of up to the 3rd order, allowing for efficient and streamlined microwave structure design. Through our approach, we offer a satisfactory explanation of the band structure of SRR chains using a microwave-hopping model, which facilitates the exploration of exotic photonic band structures based on tight-binding theory.

3.
BMC Infect Dis ; 23(1): 483, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37468843

RESUMO

BACKGROUND: Bacterial vaginosis (BV) is one of the most common infections among women of reproductive age and accounts for 15-50% of infections globally. The role played by folate in the pathogenesis and progression of BV is poorly understood. The aim of this study was to investigate the association between serum folate, red blood cell (RBC) folate, and BV in American women. METHODS: 1,954 participants from the 2001-2004 National Health and Nutrition Examination Survey (NHANES) program were included in this study. Multiple logistic regression was used to analyze the association between serum folate, RBC folate, and BV, and covariates including race, age, education level, and body mass index were used to construct adjusted models. Stratified analysis was used to explore the stability of the above associations in different populations. RESULTS: In the present cross-sectional study, we found that serum folate and RBC folate were inversely associated with the risk of BV. In the fully adjusted model, the risk of BV was reduced by 35% (OR=0.65, 95% CI: 0.51~0.83, p=0.0007) in the highest serum folate group and 32% (OR=0.68, 95% CI: 0.53~0.87, p=0.0023) in the highest RBC folate group compared to the lowest group. CONCLUSIONS: The results of this study indicated that serum folate and RBC folate were inversely associated with the risk of BV folate supplementation may play an important role in the prevention and management of BV.


Assuntos
Ácido Fólico , Vaginose Bacteriana , Humanos , Feminino , Estados Unidos/epidemiologia , Vaginose Bacteriana/epidemiologia , Inquéritos Nutricionais , Estudos Transversais , Modelos Logísticos
4.
Sensors (Basel) ; 23(3)2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36772455

RESUMO

A multi-gas sensing system was developed based on the detection principle of the non-dispersive infrared (NDIR) method, which used a broad-spectra light source, a tunable Fabry-Pérot (FP) filter detector, and a flexible low-loss infrared waveguide as an absorption cell. CH4, C2H6, and CO2 gases were detected by the system. The concentration of CO2 could be detected directly, and the concentrations of CH4 and C2H6 were detected using a PCA-BP neural network algorithm because of the interference of CH4 and C2H6. The detection limits were achieved to be 2.59 ppm, 926 ppb, and 114 ppb for CH4, C2H6, and CO2 with an averaging time of 429 s, 462 s, and 297 s, respectively. The root mean square error of prediction (RMSEP) of CH4 and C2H6 were 10.97 ppm and 2.00 ppm, respectively. The proposed system and method take full advantage of the multi-component gas measurement capability of the mid-infrared broadband source and achieve a compromise between performance and system cost.

5.
Molecules ; 28(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37570702

RESUMO

The aim of this study was to microencapsulate probiotic bacteria (Lactobacillus acidophilus 11073) using whey-protein-isolate (WPI)-octenyl-succinic-anhydride-starch (OSA-starch)-complex coacervates and to investigate the effects on probiotic bacterial viability during spray drying, simulated gastrointestinal digestion, thermal treatment and long-term storage. The optimum mixing ratio and pH for the preparation of WPI-OSA-starch-complex coacervates were determined to be 2:1 and 4.0, respectively. The combination of WPI and OSA starch under these conditions produced microcapsules with smoother surfaces and more compact structures than WPI-OSA starch alone, due to the electrostatic attraction between WPI and OSA starch. As a result, WPI-OSA-starch microcapsules showed significantly (p < 0.05) higher viability (95.94 ± 1.64%) after spray drying and significantly (p < 0.05) better protection during simulated gastrointestinal digestion, heating (65 °C/30 min and 75 °C/10 min) and storage (4/25 °C for 12 weeks) than WPI-OSA-starch microcapsules. These results demonstrated that WPI-OSA-starch-complex coacervates have excellent potential as a novel wall material for probiotic microencapsulation.


Assuntos
Probióticos , Soro do Leite , Cápsulas/química , Amido/química , Anidridos , Viabilidade Microbiana
6.
Mol Psychiatry ; 26(12): 7425-7435, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34376822

RESUMO

Ketamine produces a rapid antidepressant response in patients with major depressive disorder (MDD), but the underlying mechanisms appear multifaceted. One hypothesis, proposes that by antagonizing NMDA receptors on GABAergic interneurons, ketamine disinhibits afferens to glutamatergic principal neurons and increases extracellular glutamate levels. However, ketamine seems also to reduce rapid glutamate release at some synapses. Therefore, clinical studies in MDD patients have stressed the need to identify mechanisms whereby ketamine decreases presynaptic activity and glutamate release. In the present study, the effect of ketamine and its antidepressant metabolite, (2R,6R)-HNK, on neuronally derived glutamate release was examined in rodents. We used FAST methodology to measure depolarization-evoked extracellular glutamate levels in vivo in freely moving or anesthetized animals, synaptosomes to detect synaptic recycling ex vivo and primary cortical neurons to perform functional imaging and to examine intracellular signaling in vitro. In all these versatile approaches, ketamine and (2R,6R)-HNK reduced glutamate release in a manner which could be blocked by AMPA receptor antagonism. Antagonism of adenosine A1 receptors, which are almost exclusively expressed at nerve terminals, also counteracted ketamine's effect on glutamate release and presynaptic activity. Signal transduction studies in primary neuronal cultures demonstrated that ketamine reduced P-T286-CamKII and P-S9-Synapsin, which correlated with decreased synaptic vesicle recycling. Moreover, systemic administration of A1R antagonist counteracted the antidepressant-like actions of ketamine and (2R,6R)-HNK in the forced swim test. To conclude, by studying neuronally released glutamate, we identified a novel retrograde adenosinergic feedback mechanism that mediate inhibitory actions of ketamine on glutamate release that may contribute to its rapid antidepressant action.


Assuntos
Transtorno Depressivo Maior , Ketamina , Animais , Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Ácido Glutâmico/metabolismo , Humanos , Ketamina/metabolismo , Ketamina/farmacologia , Receptor A1 de Adenosina/metabolismo , Receptor A1 de Adenosina/uso terapêutico , Receptores de N-Metil-D-Aspartato/metabolismo
7.
Angew Chem Int Ed Engl ; 60(33): 18022-18030, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-33904641

RESUMO

Many diseases are polygenic and can only be treated efficiently with drugs that modulate multiple targets. However, rational design of compounds with multi-target profiles is rarely pursued because it is considered too difficult, in particular if the drug must enter the central nervous system. Here, a structure-based strategy to identify dual-target ligands of G-protein-coupled receptors is presented. We use this approach to design compounds that both antagonize the A2A adenosine receptor and activate the D2 dopamine receptor, which have excellent potential as antiparkinson drugs. Atomic resolution models of the receptors guided generation of a chemical library with compounds designed to occupy orthosteric and secondary binding pockets in both targets. Structure-based virtual screens identified ten compounds, of which three had affinity for both targets. One of these scaffolds was optimized to nanomolar dual-target activity and showed the predicted pharmacodynamic effect in a rat model of Parkinsonism.


Assuntos
Antiparkinsonianos/farmacologia , Desenho de Fármacos , Receptor A2A de Adenosina/metabolismo , Receptores de Dopamina D2/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Antiparkinsonianos/síntese química , Antiparkinsonianos/química , Avaliação Pré-Clínica de Medicamentos , Humanos , Ligantes , Estrutura Molecular , Ratos , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química
8.
Science ; 385(6712): eado6593, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39208104

RESUMO

Opioids are widely used, effective analgesics to manage severe acute and chronic pain, although they have recently come under scrutiny because of epidemic levels of abuse. While these compounds act on numerous central and peripheral pain pathways, the neuroanatomical substrate for opioid analgesia is not fully understood. By means of single-cell transcriptomics and manipulation of morphine-responsive neurons, we have identified an ensemble of neurons in the rostral ventromedial medulla (RVM) that regulates mechanical nociception in mice. Among these, forced activation or silencing of excitatory RVMBDNF projection neurons mimicked or completely reversed morphine-induced mechanical antinociception, respectively, via a brain-derived neurotrophic factor (BDNF)/tropomyosin receptor kinase B (TrkB)-dependent mechanism and activation of inhibitory spinal galanin-positive neurons. Our results reveal a specific RVM-spinal circuit that scales mechanical nociception whose function confers the antinociceptive properties of morphine.


Assuntos
Analgésicos Opioides , Fator Neurotrófico Derivado do Encéfalo , Bulbo , Morfina , Neurônios , Nociceptividade , Animais , Masculino , Camundongos , Analgésicos Opioides/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Bulbo/efeitos dos fármacos , Bulbo/metabolismo , Camundongos Endogâmicos C57BL , Morfina/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/fisiologia , Nociceptividade/efeitos dos fármacos , Receptor trkB/metabolismo , Análise de Célula Única , Medula Espinal/efeitos dos fármacos , Transcriptoma , Feminino
9.
Adv Mater ; 36(38): e2405889, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39054923

RESUMO

Rechargeable aqueous zinc batteries are promising in next-generation sustainable energy storage. However, the low zinc (Zn) metal anode reversibility and utilization in aqueous electrolytes due to Zn corrosion and poor Zn2+ deposition kinetics significantly hinder the development of Zn-ion batteries. Here, a dual salt/dual solvent electrolyte composed of Zn(BF4)2/Zn(Ac)2 in water/TEGDME (tetraethylene glycol dimethyl ether) solvents to achieve reversible Zn anode at an ultrahigh depth of discharge (DOD) is developed. An "inner co-salt and outer co-solvent" synergistic effect in this unique dual salt/dual solvent system is revealed. Experimental results and theoretical calculations provide evidence that the ether co-solvent inhibits water activity by forming hydrogen bonding with the water and coordination effects with the proton in the outer Zn2+ solvation structure. Meanwhile, the anion of zinc acetate co-salt enters the inner Zn2+ solvation structure, thereby accelerating the desolvation kinetics. Strikingly, based on the electrolyte design, the zinc anode shows high reversibility at an ultrahigh utilization of 60% DOD with 99.80% Coulombic efficiency and 9.39 mAh cm-2 high capacity. The results far exceed the performance reported in electrolyte design work recently. The work provides fundamental insights into inner co-salt and outer co-solvent synergistic regulation in multifunctional electrolytes for reversible aqueous metal-ion batteries.

10.
Adv Mater ; 36(18): e2312982, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38287732

RESUMO

Nanoconfinement of cations in layered oxide cathode is an important approach to realize advanced zinc ion storage performance. However, thus far, the conventional hydrothermal/solvothermal route for this nanoconfinement has been restricted to its uncontrollable phase structure and the difficulty on the multiple cation co-confinement simultaneously. Herein, this work reports a general, supramolecular self-assembly of ultrathin V2O5 nanosheets using various unitary cations including Na+, K+, Mg2+, Ca2+, Zn2+, Al3+, NH4 +, and multiple cations (NH4 + + Na+, NH4 + + Na+ + Ca2+, NH4 + + Na+ + Ca2+ +Mg2+). The unitary cation confinement results in a remarkable increase in the specific capacity and Zn-ion diffusion kinetics, and the multiple cation confinement gives rise to superior structural and cycling stability by multiple cation synergetic pillaring effect. The optimized diffusion coefficient of Zn-ion (7.5 × 10-8 cm2 s-1) in this assembly series surpasses most of the V-based cathodes reported up to date. The work develops a novel multiple-cations nanoconfinement strategy toward high-performance cathode for aqueous battery. It also provides new insights into the guest cation regulation of zinc-ion diffusion kinetics through a general, supramolecular assembly pathway.

11.
Sci Adv ; 10(32): eadn1524, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39110804

RESUMO

Artificial intelligence is revolutionizing protein structure prediction, providing unprecedented opportunities for drug design. To assess the potential impact on ligand discovery, we compared virtual screens using protein structures generated by the AlphaFold machine learning method and traditional homology modeling. More than 16 million compounds were docked to models of the trace amine-associated receptor 1 (TAAR1), a G protein-coupled receptor of unknown structure and target for treating neuropsychiatric disorders. Sets of 30 and 32 highly ranked compounds from the AlphaFold and homology model screens, respectively, were experimentally evaluated. Of these, 25 were TAAR1 agonists with potencies ranging from 12 to 0.03 µM. The AlphaFold screen yielded a more than twofold higher hit rate (60%) than the homology model and discovered the most potent agonists. A TAAR1 agonist with a promising selectivity profile and drug-like properties showed physiological and antipsychotic-like effects in wild-type but not in TAAR1 knockout mice. These results demonstrate that AlphaFold structures can accelerate drug discovery.


Assuntos
Descoberta de Drogas , Receptores Acoplados a Proteínas G , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Animais , Camundongos , Humanos , Camundongos Knockout , Psicotrópicos/farmacologia , Psicotrópicos/química , Simulação de Acoplamento Molecular , Ligantes
12.
Ultrason Sonochem ; 100: 106638, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37826892

RESUMO

The influence of ultrasonic treatment (100-500 W, 30 min) on the molecular structures and emulsifying properties of Zanthoxylum seed protein (ZSP) was explored for the first time in this work. Research results indicated that the all ultrasonic treatments at different power levels decreased the particle size but increased the surface charge of ZSP. In addition, the ultrasonic treatments induced the structural unfolding of the ZAP, as indicated by the increase in α-helix, ultraviolet-visible absorbance, surface hydrophobicity and the amount of surface free sulfhydryl groups, as well as the decrease in ß-sheet and intrinsic fluorescence intensity. As a result, the significantly (p < 0.05) increased emulsifying activity index (EAI) and emulsion stability index (ESI) of ZSP were observed after ultrasonic treatment. In addition, the emulsion prepared by ultrasonically treated ZSP exhibited the smaller and more uniform droplets with significantly improved stability against environmental stress (temperature, salt concentration, pH), creaming and oxidation due to the increased ratio of interfacially adsorbed ZSP. Furthermore, ultrasonic treatment at 400 W was found to be the optimum condition for modification. These findings will provide a theoretical foundation for the utilization of ultrasound in enhancing the emulsifying properties of ZSP and promoting its application in the field of food processing.


Assuntos
Zanthoxylum , Emulsões/química , Ultrassom , Fenômenos Químicos , Interações Hidrofóbicas e Hidrofílicas , Emulsificantes/química
13.
NPJ Parkinsons Dis ; 8(1): 71, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672421

RESUMO

α-Synuclein (α-syn) is a key molecule linked to Parkinson's disease pathology. Physiologically, the monomeric α-syn in the presynaptic termini is involved in regulation of neurotransmission, but the pathophysiology of extracellular monomeric α-syn is still unknown. Utilizing both in vivo and in vitro approaches, we investigated how extracellular α-syn impact presynaptic structure and function. Our data revealed that treatment with exogenous α-syn leads to increased tonic and decreased depolarization-evoked synaptic vesicle (SV) recycling and glutamate release. This was associated with mobilization of molecularly distinct SV pools and reorganization of active zone components. Our study also showed that exogenous α-syn impaired neuronal cholesterol level and that the cholesterol binding domain of α-syn was sufficient to exert the same presynaptic phenotype as the full-length protein. The present study sheds new light on physiological functions of extracellular α-syn in overall maintenance of presynaptic activity that involves the reorganization of both presynaptic compartment and cholesterol-rich plasma membrane domains.

14.
Anal Sci ; 38(6): 889-897, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35403957

RESUMO

To measure two tumor biomarkers, alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA), a dual-carrier CL sensor with restriction enzyme digestion (Exo I) and aptamer technology utilizing gold nanoparticles (hydroxylamine amplification) and horseradish peroxidase (HRP) as the CL signal enhancement in the sensing strategy was formed. These nanoparticles and nano-enzyme were precisely detected and tagged to the appropriate position attributable to the particular recognition of biotin and streptavidin. In this sensing strategy, target markers were further enriched and recognized sensitively by CL following enrichment, and matching strong chemical signals were collected under luminol catalysis, allowing for marker identification. For CEA (0.1-80 ng/mL) and AFP (2-500 ng/mL), the proposed method has a large linear range, with detection limits of 36.6 pg/mL and 0.94 ng/mL, respectively.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Biomarcadores Tumorais , Técnicas Biossensoriais/métodos , Antígeno Carcinoembrionário , Digestão , Ouro , Peroxidase do Rábano Silvestre , Imunoensaio/métodos , Limite de Detecção , Luminescência , alfa-Fetoproteínas
15.
Biol Psychiatry ; 90(1): 16-27, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33579534

RESUMO

BACKGROUND: Monoamine oxidase inhibitors (MAOIs) exert therapeutic actions by elevating extracellular levels of monoamines in the brain. Irreversible MAOIs cause serious hypertensive crises owing to peripheral accumulation of tyramine, but the role of tyramine in the central effects of MAOIs remains elusive, an issue addressed herein. To achieve robust inhibition of MAOA/B, the clinically used antidepressant tranylcypromine (TCP) was employed. METHODS: Behavioral, histological, mass spectrometry imaging, and biosensor-mediated measures of glutamate were conducted with MAOIs in wild-type and TAAR1-knockout (KO) mice. RESULTS: Both antidepressant and locomotion responses to TCP were enhanced in TAAR1-KO mice. A recently developed fluoromethylpyridinium-based mass spectrometry imaging method revealed robust accumulation of striatal tyramine on TCP administration. Furthermore, tyramine accumulation was higher in TAAR1-KO versus wild-type mice, suggesting a negative feedback mechanism for TAAR1 in sensing tyramine levels. Combined histoenzymological and immunohistological studies revealed hitherto unknown TAAR1 localization in brain areas projecting to the substantia nigra/ventral tegmental area. Using an enzyme-based biosensor technology, we found that both TCP and tyramine reduced glutamate release in the substantia nigra in wild-type but not in TAAR1-KO mice. Moreover, glutamate measures in freely moving animals treated with TCP demonstrated that TAAR1 prevents glutamate accumulation in the substantia nigra during hyperlocomotive states. CONCLUSIONS: These observations suggest that tyramine, in interaction with glutamate, is involved in centrally mediated behavioral, transcriptional, and neurochemical effects of MAOIs.


Assuntos
Ácido Glutâmico , Inibidores da Monoaminoxidase , Receptores Acoplados a Proteínas G/fisiologia , Tiramina , Animais , Camundongos , Camundongos Knockout , Monoaminoxidase , Inibidores da Monoaminoxidase/farmacologia
16.
Neuropharmacology ; 162: 107829, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31666199

RESUMO

Parkinson's disease (PD) is characterized by progressive loss of midbrain dopaminergic neurons and treated with the dopamine precursor, 3,4-dihydroxy-l-phenylalanine (L-DOPA). Prolonged L-DOPA treatment is however associated with waning efficacy and the induction of L-DOPA induced dyskinesia (LID). GPR88 is an orphan G-protein Coupled Receptor (GPCR) expressed in dopaminoceptive striatal medium spiny neurons (MSNs) and their afferent corticostriatal glutamatergic neurons. Here, we studied the role of GPR88 in experimental parkinsonism and LID. Chronic L-DOPA administration to male GPR88 KO mice, subjected to unilateral 6-hydroxydopamine (6-OHDA) lesions of the medial forebrain bundle, resulted in more rotations than in their WT counterparts. Conversely, GPR88 KO mice had a lower abnormal involuntary movements (AIMs) score. These behavioral responses were accompanied by altered transcription of L-DOPA upregulated genes in lesioned GPR88 KO compared to WT striata. In accordance with a role for serotonin neurons in LID development, WT but not GPR88 KO striata exhibited 5-hydroxytryptamine displacement upon repeated L-DOPA treatment. Intact male GPR88 KO mice showed diminished tacrine-induced PD-like tremor and spontaneous hyperlocomotion. Dopamine and its metabolites were not increased in male GPR88 KO mice, but biosensor recordings revealed increased spontaneous/basal and evoked glutamate release in striata of male GPR88 KO mice. In conclusion, genetic deletion of GPR88 promotes l-DOPA-induced rotation and spontaneous locomotion yet suppresses the induction of LIDs and also reduces tremor. These data provide behavioral, neurochemical and molecular support that GPR88 antagonism may favour motor relief in PD patients without aggravating the induction of motor side effects.


Assuntos
Antiparkinsonianos/farmacologia , Corpo Estriado/metabolismo , Discinesia Induzida por Medicamentos/genética , Levodopa/farmacologia , Locomoção/efeitos dos fármacos , Movimento/efeitos dos fármacos , Transtornos Parkinsonianos/genética , Receptores Acoplados a Proteínas G/genética , Adrenérgicos/toxicidade , Animais , Inibidores da Colinesterase/toxicidade , Corpo Estriado/efeitos dos fármacos , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Discinesia Induzida por Medicamentos/etiologia , Discinesia Induzida por Medicamentos/metabolismo , Discinesia Induzida por Medicamentos/fisiopatologia , Neurônios GABAérgicos , Ácido Glutâmico/metabolismo , Locomoção/genética , Masculino , Feixe Prosencefálico Mediano , Camundongos , Camundongos Knockout , Plasticidade Neuronal/genética , Oxidopamina/toxicidade , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/fisiopatologia , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Acoplados a Proteínas G/fisiologia , Serotonina/metabolismo , Tacrina/toxicidade , Tremor
17.
Neuron ; 102(1): 173-183.e4, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30773347

RESUMO

Co-release of multiple neurotransmitters from secretory vesicles is common in neurons and neuroendocrine cells. However, whether and how the transmitters co-released from a single vesicle are differentially regulated remains unknown. In matrix-containing dense-core vesicles (DCVs) in chromaffin cells, there are two modes of catecholamine (CA) release from a single DCV: quantal and sub-quantal. By combining two microelectrodes to simultaneously record co-release of the native CA and ATP from a DCV, we report that (1) CA and ATP were co-released during a DCV fusion; (2) during kiss-and-run (KAR) fusion, the co-released CA was sub-quantal, whereas the co-released ATP was quantal; and (3) knockdown and knockout of the DCV matrix led to quantal co-release of both CA and ATP even in KAR mode. These findings strongly imply that, in contrast to sub-quantal CA release in chromaffin cells, fast synaptic transmission without transmitter-matrix binding is mediated exclusively via quantal release in neurons.


Assuntos
Trifosfato de Adenosina/metabolismo , Catecolaminas/metabolismo , Células Cromafins/metabolismo , Exocitose/fisiologia , Vesículas Secretórias/metabolismo , Transmissão Sináptica/fisiologia , Medula Suprarrenal/citologia , Animais , Cálcio/metabolismo , Sinalização do Cálcio , Células HEK293 , Humanos , Fusão de Membrana , Camundongos , Camundongos Knockout , Neurotransmissores/metabolismo , Técnicas de Patch-Clamp , Sinaptotagminas/genética
18.
Neuropharmacology ; 143: 38-48, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30222983

RESUMO

Riluzole is a potent neuroprotective agent which primarily inhibits excitatory neurotransmission interfering with presynaptic release, uptake and postsynaptic actions of glutamate by mechanisms that are not well understood. Riluzole and related prodrugs with improved blood brain barrier penetrance, are shown to be effective for the treatment of amyotrophic lateral sclerosis, ataxias, epilepsy and mood disorders. Our study was undertaken to decipher molecular and subcellular mechanisms of riluzole's antiglutamatergic effect, particularly focusing on presynaptic active zone structure and function. Applying multifarious live cell imaging techniques and amperometric glutamate recordings, we measured the impact of riluzole on presynaptic activity, synaptic vesicle recycling and glutamate release. Our in vitro and in vivo data revealed a unique mechanism whereby riluzole reduces the efficacy of glutamatergic transmission by selectively lowering the size of the readily releasable pool. This effect was correlated with the inhibition of protein kinase C-dependent Munc18-1 phosphorylation which is known to interfere with neurotransmitter release.


Assuntos
Antagonistas de Aminoácidos Excitatórios/farmacologia , Ácido Glutâmico/metabolismo , Fármacos Neuroprotetores/farmacologia , Riluzol/farmacologia , Transmissão Sináptica/efeitos dos fármacos , Vesículas Sinápticas/efeitos dos fármacos , Animais , Antígeno CD146/metabolismo , Células Cultivadas , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Terminações Pré-Sinápticas/efeitos dos fármacos , Terminações Pré-Sinápticas/metabolismo , Proteína Quinase C/metabolismo , Ratos Wistar , Transmissão Sináptica/fisiologia , Vesículas Sinápticas/metabolismo
19.
Transfusion ; 46(11): 1870-8, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17076840

RESUMO

BACKGROUND: The characterization of microchimerism (MC) by gene amplification has been limited by few allogeneic markers, ascertainment bias, and assay analytic performance. To address this, a panel of 12 MC assays based on insertion-deletion (InDel) polymorphisms had been optimized. STUDY DESIGN AND METHODS: The InDel assays were validated with comprehensive in vitro spiking studies at the stochastic limit of detection. Their ability was also determined to ascertain MC of unknown source genotype with both theoretical and actual donor-recipient pairs, and the assays were applied to a clinical population of 73 trauma patients who received transfusions where MC was previously characterized by HLA-based assays alone. RESULTS: In the stochastic spiking experiments, all assays were sensitive to a single copy of target DNA, and no false-positive amplification occurred among 1128 samples studied. Among 219 theoretical donor-recipient pairs, informative alleles existed for 99.5 percent with both InDel and HLA compared to 91.3 percent with HLA alone. In the clinical population, 33 cases of MC were detected (9 more cases than by HLA-DR alone) in the nonleukoreduced (non-LR) group and 8 cases (1 more case than by HLA-DR) in the LR group for the short-term follow-up. Among 27 long-term follow-up samples, 8 cases were detected overall (3 more cases than by HLA-DR alone). CONCLUSION: It is concluded that an InDel-based assay panel has excellent technical performance characteristics while also allowing for ascertainment of some MC cases not detectable with HLA alone. The tandem use of both the InDel and the HLA provides a powerful tool for the enhanced ascertainment of MC.


Assuntos
Quimerismo , Antígenos HLA-DR/genética , Mutagênese Insercional , Reação em Cadeia da Polimerase , Polimorfismo Genético , Deleção de Sequência , Adulto , Doadores de Sangue , Reações Falso-Positivas , Feminino , Seguimentos , Humanos , Procedimentos de Redução de Leucócitos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Reprodutibilidade dos Testes , Ferimentos e Lesões/complicações , Ferimentos e Lesões/genética , Ferimentos e Lesões/terapia
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