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1.
Plant Dis ; 105(9): 2290-2294, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33591832

RESUMO

Mungbean (Vigna radiata (L.) R. Wilczek), an important legume crop in Asia, is primarily cultivated in the central-southern region of western Taiwan. In 2020, mungbean exhibiting typical phytoplasma-induced disease symptoms such as witches' broom, phyllody, virescence, and proliferation was observed in Yunlin County, Taiwan. Moreover, the seed harvested from diseased plants displayed premature germination. Transmission electron microscopy examination of leaf veins prepared from symptomatic mungbean demonstrated that the occlusion of sieve tubes resulted from the accumulation of phytoplasma-like bodies in sieve elements along with filament-like structures in sieve pores. The association of phytoplasma in symptomatic mungbean was confirmed by PCR analyses of the 16S ribosomal RNA (rRNA) and immunodominant membrane protein genes. Further analyses of the 16S rRNA-based phylogenetic tree and the iPhyClassifier-based virtual restriction fragment length polymorphism study demonstrated that the phytoplasma-associated mungbean phyllody disease identified in this study belongs to the 16SrII-V subgroup. BLAST analysis and the phylogenetic analysis indicated that the SAP11-like protein identified in mungbean phyllody disease is identical to peanut witches' broom phytoplasma SAP11, which explains the witches' broom phenotype observed in symptomatic mungbean. The results described in this report confirm that the 16SrII-V phytoplasma, a widely distributed phytoplasma associated with peanut witches' broom disease in Taiwan, has also infected mungbean. This is not only the first instance of mungbean phyllody disease found in Taiwan but also the first instance of mungbean phyllody disease caused by 16SrII-V subgroup phytoplasma.


Assuntos
Fabaceae , Phytoplasma , Vigna , DNA Bacteriano , Filogenia , Phytoplasma/genética , Doenças das Plantas , RNA Ribossômico 16S/genética , Taiwan
2.
Opt Express ; 27(8): 11709-11720, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31053013

RESUMO

We develop a front-to-end solution where the shift of chromaticity from scattering of plasmonic nanoparticles is used as the reporter for nano-environmental refractive index variation. By co-projecting possible power combinations of RGB LEDs and digitized color grid density of CCD with various luminance onto the CIE 1931 chromaticity diagram, optimum condition for nanoenvironment sensing can be achieved. The highest resolution for local refractive index change is 0.0021 per distinguishable color, which is higher than that of a typical handheld spectrometer by 4.8 times. This result shows great potential in simplifying nano-environment sensing instruments and is particularly useful for multi-point dynamical process.

3.
Neurobiol Dis ; 117: 181-188, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29859869

RESUMO

Neural network dysfunction may contribute to functional decline and disease progression in neurodegenerative disorders. Diverse lines of evidence suggest that neuronal accumulation of tau promotes network dysfunction and cognitive decline. The A152T-variant of human tau (hTau-A152T) increases the risk of Alzheimer's disease (AD) and several other tauopathies. When overexpressed in neurons of transgenic mice, it causes age-dependent neuronal loss and cognitive decline, as well as non-convulsive epileptic activity, which is also seen in patients with AD. Using intracranial EEG recordings with electrodes implanted over the parietal cortex, we demonstrate that hTau-A152T increases the power of brain oscillations in the 0.5-6 Hz range more than wildtype human tau in transgenic lines with comparable levels of human tau protein in brain, and that genetic ablation of endogenous tau in Mapt-/- mice decreases the power of these oscillations as compared to wildtype controls. Suppression of hTau-A152T production in doxycycline-regulatable transgenic mice reversed their abnormal network activity. Treatment of hTau-A152T mice with the antiepileptic drug levetiracetam also rapidly and persistently reversed their brain dysrhythmia and network hypersynchrony. These findings suggest that both the level and the sequence of tau modulate the power of specific brain oscillations. The potential of EEG spectral changes as a biomarker deserves to be explored in clinical trials of tau-lowering therapeutics. Our results also suggest that levetiracetam treatment is able to counteract tau-dependent neural network dysfunction. Tau reduction and levetiracetam treatment may be of benefit in AD and other conditions associated with brain dysrhythmias and network hypersynchrony.


Assuntos
Encéfalo/metabolismo , Ritmo Delta/fisiologia , Neurônios/metabolismo , Ritmo Teta/fisiologia , Proteínas tau/metabolismo , Animais , Encéfalo/patologia , Ondas Encefálicas/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/patologia
4.
Nature ; 489(7416): 385-90, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-22914087

RESUMO

Haploinsufficiency of the SCN1A gene encoding voltage-gated sodium channel Na(V)1.1 causes Dravet's syndrome, a childhood neuropsychiatric disorder including recurrent intractable seizures, cognitive deficit and autism-spectrum behaviours. The neural mechanisms responsible for cognitive deficit and autism-spectrum behaviours in Dravet's syndrome are poorly understood. Here we report that mice with Scn1a haploinsufficiency exhibit hyperactivity, stereotyped behaviours, social interaction deficits and impaired context-dependent spatial memory. Olfactory sensitivity is retained, but novel food odours and social odours are aversive to Scn1a(+/-) mice. GABAergic neurotransmission is specifically impaired by this mutation, and selective deletion of Na(V)1.1 channels in forebrain interneurons is sufficient to cause these behavioural and cognitive impairments. Remarkably, treatment with low-dose clonazepam, a positive allosteric modulator of GABA(A) receptors, completely rescued the abnormal social behaviours and deficits in fear memory in the mouse model of Dravet's syndrome, demonstrating that they are caused by impaired GABAergic neurotransmission and not by neuronal damage from recurrent seizures. These results demonstrate a critical role for Na(V)1.1 channels in neuropsychiatric functions and provide a potential therapeutic strategy for cognitive deficit and autism-spectrum behaviours in Dravet's syndrome.


Assuntos
Transtorno Autístico/tratamento farmacológico , Transtorno Autístico/fisiopatologia , Moduladores GABAérgicos/uso terapêutico , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Canais de Sódio/genética , Canais de Sódio/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Ácido gama-Aminobutírico/metabolismo , Animais , Ansiedade/fisiopatologia , Transtorno Autístico/complicações , Transtorno Autístico/genética , Clonazepam/farmacologia , Clonazepam/uso terapêutico , Epilepsias Mioclônicas/complicações , Epilepsias Mioclônicas/genética , Epilepsias Mioclônicas/fisiopatologia , Moduladores GABAérgicos/farmacologia , Neurônios GABAérgicos/metabolismo , Haploinsuficiência/genética , Heterozigoto , Hipocampo/citologia , Proteínas de Homeodomínio/genética , Hipercinese/fisiopatologia , Interneurônios/metabolismo , Masculino , Memória , Camundongos , Canal de Sódio Disparado por Voltagem NAV1.1 , Comportamento Social , Percepção Espacial , Transtorno de Movimento Estereotipado/fisiopatologia , Síndrome , Fatores de Transcrição/genética
5.
Proc Natl Acad Sci U S A ; 111(30): E3139-48, 2014 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-25024183

RESUMO

Haploinsufficiency of the voltage-gated sodium channel NaV1.1 causes Dravet syndrome, an intractable developmental epilepsy syndrome with seizure onset in the first year of life. Specific heterozygous deletion of NaV1.1 in forebrain GABAergic-inhibitory neurons is sufficient to cause all the manifestations of Dravet syndrome in mice, but the physiological roles of specific subtypes of GABAergic interneurons in the cerebral cortex in this disease are unknown. Voltage-clamp studies of dissociated interneurons from cerebral cortex did not detect a significant effect of the Dravet syndrome mutation on sodium currents in cell bodies. However, current-clamp recordings of intact interneurons in layer V of neocortical slices from mice with haploinsufficiency in the gene encoding the NaV1.1 sodium channel, Scn1a, revealed substantial reduction of excitability in fast-spiking, parvalbumin-expressing interneurons and somatostatin-expressing interneurons. The threshold and rheobase for action potential generation were increased, the frequency of action potentials within trains was decreased, and action-potential firing within trains failed more frequently. Furthermore, the deficit in excitability of somatostatin-expressing interneurons caused significant reduction in frequency-dependent disynaptic inhibition between neighboring layer V pyramidal neurons mediated by somatostatin-expressing Martinotti cells, which would lead to substantial disinhibition of the output of cortical circuits. In contrast to these deficits in interneurons, pyramidal cells showed no differences in excitability. These results reveal that the two major subtypes of interneurons in layer V of the neocortex, parvalbumin-expressing and somatostatin-expressing, both have impaired excitability, resulting in disinhibition of the cortical network. These major functional deficits are likely to contribute synergistically to the pathophysiology of Dravet syndrome.


Assuntos
Potenciais de Ação , Epilepsias Mioclônicas/metabolismo , Neurônios GABAérgicos/metabolismo , Neocórtex/metabolismo , Parvalbuminas/biossíntese , Células Piramidais/metabolismo , Somatostatina/biossíntese , Animais , Modelos Animais de Doenças , Epilepsias Mioclônicas/genética , Epilepsias Mioclônicas/patologia , Neurônios GABAérgicos/patologia , Regulação da Expressão Gênica , Camundongos , Camundongos Mutantes , Canal de Sódio Disparado por Voltagem NAV1.1/biossíntese , Canal de Sódio Disparado por Voltagem NAV1.1/genética , Neocórtex/patologia , Parvalbuminas/genética , Células Piramidais/patologia , Somatostatina/genética
6.
Brain ; 138(Pt 8): 2219-33, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26017580

RESUMO

Neurological and psychiatric syndromes often have multiple disease traits, yet it is unknown how such multi-faceted deficits arise from single mutations. Haploinsufficiency of the voltage-gated sodium channel Nav1.1 causes Dravet syndrome, an intractable childhood-onset epilepsy with hyperactivity, cognitive deficit, autistic-like behaviours, and premature death. Deletion of Nav1.1 channels selectively impairs excitability of GABAergic interneurons. We studied mice having selective deletion of Nav1.1 in parvalbumin- or somatostatin-expressing interneurons. In brain slices, these deletions cause increased threshold for action potential generation, impaired action potential firing in trains, and reduced amplification of postsynaptic potentials in those interneurons. Selective deletion of Nav1.1 in parvalbumin- or somatostatin-expressing interneurons increases susceptibility to thermally-induced seizures, which are strikingly prolonged when Nav1.1 is deleted in both interneuron types. Mice with global haploinsufficiency of Nav1.1 display autistic-like behaviours, hyperactivity and cognitive impairment. Haploinsufficiency of Nav1.1 in parvalbumin-expressing interneurons causes autistic-like behaviours, but not hyperactivity, whereas haploinsufficiency in somatostatin-expressing interneurons causes hyperactivity without autistic-like behaviours. Heterozygous deletion in both interneuron types is required to impair long-term spatial memory in context-dependent fear conditioning, without affecting short-term spatial learning or memory. Thus, the multi-faceted phenotypes of Dravet syndrome can be genetically dissected, revealing synergy in causing epilepsy, premature death and deficits in long-term spatial memory, but interneuron-specific effects on hyperactivity and autistic-like behaviours. These results show that multiple disease traits can arise from similar functional deficits in specific interneuron types.


Assuntos
Epilepsias Mioclônicas/genética , Deleção de Genes , Mutação/genética , Canal de Sódio Disparado por Voltagem NAV1.1/genética , Potenciais de Ação/fisiologia , Animais , Epilepsias Mioclônicas/diagnóstico , Epilepsia/genética , Feminino , Neurônios GABAérgicos/metabolismo , Heterozigoto , Hipocampo/fisiopatologia , Masculino , Camundongos , Fenótipo
7.
Bioprocess Biosyst Eng ; 39(6): 937-44, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26915095

RESUMO

A fuzzy logic feedback control system was developed for process monitoring and feeding control in fed-batch enzymatic hydrolysis of a lignocellulosic biomass, dilute acid-pretreated corn stover. Digested glucose from hydrolysis reaction was assigned as input while doser feeding time and speed of pretreated biomass were responses from fuzzy logic control system. Membership functions for these three variables and rule-base were created based on batch hydrolysis data. The system response was first tested in LabVIEW environment then the performance was evaluated through real-time hydrolysis reaction. The feeding operations were determined timely by fuzzy logic control system and efficient responses were shown to plateau phases during hydrolysis. Feeding of proper amount of cellulose and maintaining solids content was well balanced. Fuzzy logic proved to be a robust and effective online feeding control tool for fed-batch enzymatic hydrolysis.


Assuntos
Celulase/metabolismo , Lógica Fuzzy , Lignina/metabolismo , Biomassa , Hidrólise
8.
Opt Express ; 23(25): 32113-29, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26699002

RESUMO

We demonstrate an as yet unused method to sieve, localize, and steer plasmonic hot spot within metallic nano-interstices close to percolation threshold. Multicolor superlocalization of plasmon mode within 60 nm was constantly achieved by chirp-manipulated superresolved four wave mixing (FWM) images. Since the percolated film is strongly plasmonic active and structurally multiscale invariant, the present method provides orders of magnitude enhanced light localization within single metallic nano-interstice, and can be universally applied to any region of the random film. The result, verified by the maximum likelihood estimation (MLE) and deconvolution stochastic optical reconstruction microscopy (deconSTORM) algorithm, may contribute to label-free multiplex superlocalized spectroscopy of single molecule and sub-cellular activity monitoring combining hot spot steering capability.

9.
Biotechnol Bioeng ; 112(7): 1376-82, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25656971

RESUMO

A mathematical optimal control strategy for feeding operation was developed for fed-batch enzymatic hydrolysis of dilute acid pretreated lignocellulosic biomass based on a modified epidemic model. Cellulose conversion was maximized and glucose concentration achieved highest possible value over a fixed hydrolysis time. Boundaries of feeding rate and lignin content were set for feasible controls. Using the optimal control feeding strategy, glucose concentration and accumulated cellulose conversion reached up to 77.31 g/L and 72.08% in 100 h, which are 108.76% and 37.50% higher than in batch hydrolysis with same amount of enzyme consumption. Solids content in feeding source has a significant interference on system mass transfer. Optimal control is a useful tool for guiding operations in fed-batch and continuous processes as it enables process optimization through clear objective functions and feasible controls.


Assuntos
Biomassa , Glucose/análise , Lignina/metabolismo , Biotransformação , Hidrólise , Modelos Teóricos
10.
Environ Sci Technol ; 48(13): 7333-40, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24901379

RESUMO

Photodegradation is the major pathway of methylmercury (MeHg) degradation in many surface waters. However, the mechanism of MeHg photodegradation is still not completely understood. Dissolved organic matter (DOM) is expected to play a critical role in MeHg photodegradation. By using several techniques, including N2/O2 purging and the addition of stable isotope (Me(201)Hg), scavengers, competing ligands, and a singlet oxygen ((1)O2) generator, the role played by MeHg-DOM complexation in MeHg photodegradation of Everglades surface water was investigated. DOM appeared to be involved in MeHg photodegradation via the formation MeHg-DOM complexes based on three findings: (1) MeHg was quickly photodegraded in solutions containing DOM extracts; (2) degradation of MeHg did not occur in deionized water; and (3) addition of competing complexation reagents (dithiothreitol-DTT) dramatically prohibited the photodegradation of MeHg in Everglades water. Further experiments indicated that free radicals/reactive oxygen species, including hydroxyl radical (·OH), (1)O2, triplet excited state of DOM ((3)DOM*), and hydrated electron (e(-)aq), played a minor role in MeHg photodegradation in Everglades water, based on the results of scavenger addition, (1)O2 generator addition and N2/O2 purging. A pathway, involving direct photodegradation of MeHg-DOM complexes via intramolecular electron transfer, is proposed as the dominant mechanism for MeHg photodegradation in Everglades water.


Assuntos
Ecossistema , Compostos de Metilmercúrio/química , Fotólise , Poluentes Químicos da Água/química , Água/química , Florida , Radical Hidroxila/química , Cinética , Nitrogênio/química , Oxigênio/química , Soluções , Superóxidos/química
11.
Microbiol Resour Announc ; 13(2): e0099323, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38206024

RESUMO

The complete genome sequence of Candidatus Phytoplasma australasiaticum strain WF_GM2021, which consists of one 633,005-bp circular chromosome, is presented in this work. This uncultivated plant-pathogenic bacterium is associated with soybean (Glycine max) witches' broom disease in Wufeng District, Taichung City, Taiwan.

12.
Res Sq ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38765977

RESUMO

PINK1 loss-of-function mutations and exposure to mitochondrial toxins are causative for Parkinson's disease (PD) and Parkinsonism, respectively. We demonstrate that pathological α-synuclein deposition, the hallmark pathology of idiopathic PD, induces mitochondrial dysfunction, and impairs mitophagy as evidenced by the accumulation of the PINK1 substrate pS65-Ubiquitin (pUb). We discovered MTK458, a brain penetrant small molecule that binds to PINK1 and stabilizes its active complex, resulting in increased rates of mitophagy. Treatment with MTK458 mediates clearance of accumulated pUb and α-synuclein pathology in α-synuclein pathology models in vitro and in vivo. Our findings from preclinical PD models suggest that pharmacological activation of PINK1 warrants further clinical evaluation as a therapeutic strategy for disease modification in PD.

13.
Opt Express ; 21(21): 25026-34, 2013 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-24150345

RESUMO

we develop a precise modelling where nonlocal electro-opto-thermal interactions are comprehensively included for the analysis of nonlinear Raman enhancement and plasmonic heating. An interaction enhancement factor G(IEF) is introduced to quantify the coupling between the electromagnetic field and the temperature field which is rarely considered in the estimation of Raman enhancement. For the case of isolated single nanosphere, G(IEF) can be up to ten, indicating a thermal origin which well explains the observed temperature rise, shortened blinking period, and the nonlinearly enhanced Raman cross-section. For the case of nanodimer, the suppression of plasmon heating was analyzed, demonstrating the great capability to mitigate biomolecular degradation and blinking.


Assuntos
Algoritmos , Biopolímeros/análise , Biopolímeros/química , Calefação/métodos , Sistemas Microeletromecânicos/métodos , Imagem Molecular/métodos , Análise Espectral Raman/métodos
14.
Opt Lett ; 38(24): 5342-5, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24322253

RESUMO

Broadband exciton dynamics in P3HT:PCBM blended film was observed by the femtosecond time-resolved photoluminescence sum-frequency technique. Onsager-Braun theory is applied to analyze the distribution of charge transfer radius at different energy levels. In our evaluation, the optimal diameter of P3HT fiber is about 14.3 nm for achieving the best exciton dissociation in P3HT:PCBM blended films. This technique can be readily used in the optimization of high-efficiency organic photovoltaics.

15.
bioRxiv ; 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36824886

RESUMO

PINK1 loss-of-function mutations and exposure to mitochondrial toxins are causative for Parkinson's disease (PD) and Parkinsonism, respectively. We demonstrate that pathological α-synuclein deposition, the hallmark pathology of idiopathic PD, induces mitochondrial dysfunction and impairs mitophagy, driving accumulation of the PINK1 substrate pS65-Ubiquitin (pUb) in primary neurons and in vivo. We synthesized MTK458, a brain penetrant small molecule that binds to PINK1 and stabilizes an active heterocomplex, thereby increasing mitophagy. MTK458 mediates clearance of α-synuclein pathology in PFF seeding models in vitro and in vivo and reduces pUb. We developed an ultrasensitive assay to quantify pUb levels in plasma and observed an increase in pUb in PD subjects that correlates with disease progression, paralleling our observations in PD models. Our combined findings from preclinical PD models and patient biofluids suggest that pharmacological activation of PINK1 is worthy of further study as a therapeutic strategy for disease modification in PD. Highlights: Discovery of a plasma Parkinson's Disease biomarker candidate, pS65-Ubiquitin (pUb)Plasma pUb levels correlate with disease status and progression in PD patients.Identification of a potent, brain penetrant PINK1 activator, MTK458MTK458 selectively activates PINK1 by stimulating dimerization and stabilization of the PINK1/TOM complexMTK458 drives clearance of α-synuclein pathology and normalizes pUb in in vivo Parkinson's models.

16.
Opt Express ; 20(20): 22172-80, 2012 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-23037365

RESUMO

we report on significant mode splitting in plasmonic resonators induced by intracavity resonance. In contrast to traditional dielectric resonators where only picometer range of splitting was achieved, splitting over several hundred nanometers can be obtained without using ultrahigh quality resonators. We show that by appropriately choosing the coupling length, minute reflection is sufficient to establish intracavity resonance, which effectively lifts the degeneracy of the counterpropagating modes in the resonator. The mode splitting provides two self-referenced channels enabling simultaneous monitoring of the position and the polarizability of nano-scatterers in the resonator.


Assuntos
Modelos Teóricos , Ressonância de Plasmônio de Superfície/instrumentação , Ressonância de Plasmônio de Superfície/métodos , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
17.
J Org Chem ; 77(2): 1136-42, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22168403

RESUMO

The Cu/N-ligand/TEMPO catalytic system was first applied to the aerobic oxidative synthesis of heterocycles. As demonstrated, 2-substituted quinazolines and 4H-3,1-benzoxazines were synthesized efficiently from the one-pot reaction of aldehydes with 2-aminobenzylamines and 2-aminobenzyl alcohols, respectively, by employing CuCl/DABCO/4-HO-TEMPO as the catalysts and oxygen as the terminal oxidant.


Assuntos
Benzoxazinas/síntese química , Técnicas de Química Sintética , Quinazolinas/síntese química , Aldeídos/química , Benzoxazinas/química , Catálise , Cobre/química , Estrutura Molecular , Oxidantes/química , Oxirredução , Oxigênio , Piperazinas/química , Quinazolinas/química
18.
Sci Rep ; 12(1): 20029, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36414763

RESUMO

One-step direct patterning of high definition conductive tracks in textiles is realized through laser direct writing in combination with a silver organometallic ink developed in-house. Photoreduction, nano-crystallization, and sintering are accomplished in one pass under the irradiation of a CW green laser light (λ = 532 nm) at moderate intensities (I ≥ 95 mW/mm2). By tailoring the surface tension and viscosity of the ink, high-definition conductive tracks are formed in weft-knitted polyester-Spandex composite fabrics, well-following the laser's profile with negligible coffee stain effect. Length resistance as low as 4 Ω/cm is measured and anisotropy of the gauge factor as high as 25 is achieved. The metallized fabric exhibits reversible and hysteresis-free electromechanical responses subject to high strains. Durability assessment qualifies that the as-metallized strain sensors are able to sustain their performance for over 5000 stretch/release cycles, demonstrating its potential applications in biaxial strain sensing and interactive smart textiles.


Assuntos
Têxteis , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Poliuretanos/química , Poliésteres/química
19.
Hippocampus ; 21(9): 958-67, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20865744

RESUMO

In cultured hippocampal neurons, transient receptor potential 5 (TRPC5) channels are translocated and inserted into plasma membranes of hippocampal neurons to generate nonselective cation (NSC) currents. We investigated whether TRPC5 channel translocation also contributes to the generation of NSC currents underlying the afterdepolarizations and plateau potentials (PPs) in hippocampal pyramidal cells that are induced by muscarinic receptor activation. Using a biotinylation assay to quantify the change in surface membrane proteins in acute hippocampal slices, we found that muscarinic stimulation significantly enhanced the levels of TRPC5 protein on the membrane surface but not those of TRPC1 or TRPC4 channels. We then investigated the pharmacological sensitivity of the cation current observed during muscarinic stimulation to determine if a component could be due to TRPC5 channels. The TRPC channel antagonists 2-APB and SKF96365 strongly depressed the generation of PPs, the underlying tail currents (I(tail)) and the associated dendritic Ca(2+) influx induced by muscarinic receptor activation in pyramidal neurons. High intracellular concentrations of ATP, which specifically inhibit TRPC5 channels, depressed I(tail). In addition, pretreatment with the calmodulin (CaM) inhibitor W-7, which depresses recombinant TRPC5 currents, inhibited both the cation current (I(tail)) and the surface insertion of TRPC5 channels. Finally, the phosphatidylinositide 3-kinase (PI(3)K) inhibitor wortmannin, which blocks translocation of TRPC5 channels in cell culture, also inhibited both the I(tail) and the surface insertion of TRPC5 channels. Therefore, we conclude that insertion of TRPC5 channels contributes to the generation of the prolonged afterdepolarizations following muscarinic stimulation. This altered plasma membrane expression of TRPC5 channels in pyramidal neurons may play an important role in the generation of prolonged neuronal depolarization and bursting during the epileptiform seizure discharges of epilepsy.


Assuntos
Região CA1 Hipocampal/metabolismo , Membrana Celular/metabolismo , Potenciais da Membrana/fisiologia , Células Piramidais/metabolismo , Receptores Muscarínicos/metabolismo , Canais de Cátion TRPC/metabolismo , Androstadienos/farmacologia , Animais , Compostos de Boro/farmacologia , Sinalização do Cálcio , Calmodulina/antagonistas & inibidores , Dendritos/metabolismo , Epilepsia/fisiopatologia , Epilepsia/terapia , Humanos , Potenciais da Membrana/efeitos dos fármacos , Microscopia de Fluorescência , Técnicas de Patch-Clamp , Inibidores de Fosfoinositídeo-3 Quinase , Fótons , Ratos , Ratos Sprague-Dawley , Sulfonamidas/farmacologia , Canais de Cátion TRPC/antagonistas & inibidores , Wortmanina
20.
J Subst Abuse Treat ; 130: 108426, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34118707

RESUMO

Taiwan has deemed driving under the influence of alcohol (DUI) to be criminal, and offenders are subjected to fines and jail penalties without being offered alcohol-related treatment, although alcohol use problems are prevalent in this population. We followed the recidivism records of DUI repeat offenders for one year after they had received a newly established legal-medical joint intervention program for alcohol treatment and examined factors related to postintervention recidivism. In this study, 231 DUI repeat offenders with alcohol use problems screened out by the Alcohol Use Disorder Identification Test were referred from the prosecutors' office to one psychiatric hospital for SBIRT-based alcohol treatment. We divided the participants into two groups based on the official recidivism records within the year following the end of treatment. The study used a Cox proportional hazards model to examine the hazard ratio of the baseline clinical characteristics and intervention duration for post-treatment recidivism. The study used generalized estimation equation models to examine changes in psychological symptoms and drinking behaviors over time. We found that participants who recidivated in the next year after intervention did not differ from those without recidivism records in all measurements except for the length of duration they stayed in treatment. Survival analysis determined that participants who had received the intervention for >4 months showed significantly lower rates of one-year postintervention recidivism rates The study participants showed improved psychological symptoms and drinking behaviors during the follow-up period. In conclusion, adequate duration of alcohol treatment is a significant factor associated with a lower risk of postintervention recidivism. The results provide some insight into the design of a collaborative program between legal and medical systems to reduce DUI recidivism and improve mental health of DUI repeat offenders.


Assuntos
Condução de Veículo , Criminosos , Reincidência , Consumo de Bebidas Alcoólicas , Seguimentos , Humanos , Reincidência/prevenção & controle
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