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1.
Neurobiol Dis ; : 106513, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38663634

RESUMO

In animal models of LGI1-dependent autosomal dominant lateral temporal lobe epilepsy, Kv1 channels are downregulated, suggesting their crucial involvement in epileptogenesis. The molecular basis of Kv1 channel-downregulation in LGI1 knock-out mice has not been elucidated and how the absence of this extracellular protein induces an important modification in the expression of Kv1 remains unknown. In this study we analyse by immunofluorescence the modifications in neuronal Kv1.1 and Kv1.2 distribution throughout the hippocampal formation of LGI1 knock-out mice. We show that Kv1 downregulation is not restricted to the axonal compartment, but also takes place in the somatodendritic region and is accompanied by a drastic decrease in Kv2 expression levels. Moreover, we find that the downregulation of these Kv channels is associated with a marked increase in bursting patterns. Finally, mass spectrometry uncovered key modifications in the Kv1 interactome that highlight the epileptogenic implication of Kv1 downregulation in LGI1 knock-out animals.

2.
J Cosmet Dermatol ; 23(5): 1884-1890, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38444348

RESUMO

BACKGROUND: There is a growing trend of individuals wearing cosmetics while participating in physical activities. Nonetheless, there remains a need for further understanding regarding the effects of makeup on the facial epidermis during exercise, given the existing knowledge gaps. PURPOSE: This study aimed to evaluate the effects of a cosmetic foundation cream on skin conditions during physical activity. METHODS: Forty-three healthy college students, 20 males (26.3 ± 1.5 years) and 23 females (23.1 ± 1.0 years), were enrolled in this study. Foundation cream was applied to participants on half of the face in two different areas (MT: makeup T zone and MU: makeup U zone). The other half of the face served as internal control (T: non-makeup T zone and U: non-makeup U zones). Skin levels of moisture, elasticity, pore, sebum, and oil were measured using a skin analysis device (Aramhuvis, Gyeonggi, Republic of Korea) before and after a 20-min treadmill exercise. Paired t-test and independent t-test were performed for skin condition measurements at pre- and postexercise. RESULTS: The skin moisture levels in both the T and MT significantly increased after exercise (p < 0.05) (pre-T: 24.5 ± 1.3, post-T: 38.5 ± 3.5 and pre-MT: 18.7 ± 0.7, post-MT: 40.4 ± 4.8). Elasticity also significantly improved in both the T and MT (p < 0.05) (pre-T: 25.6 ± 1.3, post-T: 41.5 ± 3.5 and pre-MT: 20.0 ± 0.9, post-MT: 41.7 ± 3.7). The size of the pores in the T zone observed a significant increase after exercise (p < 0.05) (pre-T: 41.7 ± 2.1, post-T: 47.8 ± 2.4). The sebum levels in the T zone exhibited a reduction following physical activity, whereas there was a notable increase in sebum levels in the makeup zones (p < 0.05) (pre-MT: 2.4 ± 0.7, post-MT:4.2 ± 0.8 and pre MU 1.8 ± 0.34, post MU 4.9 ± 0.9). The oil level was increased in the non-makeup zones (pre-T: 6.1 ± 1.4, post-T: 11.8 ± 2.0 and pre-U: 7.3 ± 1.5, post-U: 11.9 ± 1.9; p < 0.05) and decreased in the makeup zones (pre-MT: 13.3 ± 1.9, post-MT: 7.4 ± 2.3 and pre-MU: 22.1 ± 2.4, post-MU: 3.2 ± 1.0; p < 0.05). CONCLUSIONS: The findings suggest that using foundation cream during aerobic exercise can reduce skin oil, causing dryness. Additionally, makeup can clog pores and increase sebum production. Therefore, wearing makeup may not be recommended for people with dry skin conditions based on the results of the current study. This research offers important insights to the public, encouraging them to consider the possible consequences of using makeup while exercising.


Assuntos
Exercício Físico , Creme para a Pele , Humanos , Feminino , Masculino , Adulto Jovem , Adulto , Exercício Físico/fisiologia , Creme para a Pele/administração & dosagem , Creme para a Pele/química , Sebo/metabolismo , Elasticidade/efeitos dos fármacos , Face , Cosméticos/administração & dosagem , Cosméticos/química , Teste de Esforço , Voluntários Saudáveis , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/química , Epiderme/química , Epiderme/efeitos dos fármacos , Epiderme/fisiologia , Epiderme/metabolismo
3.
Eur J Appl Physiol ; 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38244043

RESUMO

PURPOSE: This study aimed to examine the impact of supra-maximal interval training (SMIT) and high-intensity interval training (HIIT) on cardiac auto-regulation response. METHODS: Physically active young adults volunteered to participate in the study with a randomized cross-over counterbalanced design (N = 12). HIIT sessions consisted of 20 bouts of 10 s of exercise followed by 50 s of recovery, totaling 20 min at two different intensities; "all-out (SMIT)" vs. "115-130% Wmax (HIIT)". The cardiac auto-regulation included heart rate variability (HRV) and vascular function. HRV and vascular function were measured at baseline and five different time points after acute exercise. RESULTS: The SMIT was higher in workload (31%), peak heart rate (28%), and rate of perceived exertion (40%) compared with HIIT (all p < 0.001). The R-R interval, NN50, and pNN50 measured until 60 min after acute exercise was higher in the HIIT compared with SMIT (all p < 0.05). The SMIT elicited a greater shift in ln LF/HF ratio immediately after acute exercise (3802%, p < 0.01) and induced a decrease in bilateral ba-PWV at the time point 5 min after acute exercise, persisting until 65 min after (p < 0.05). Yet, HIIT showed no change over time in the frequency domain of HRV and blood vascular tone after cessation of acute exercise. CONCLUSION: Our findings confirmed that SMIT is a more potent modulator of the autonomic nervous system compared with HIIT. Further study is needed to monitor through complete recovery to baseline, to understand acute cardiac auto-regulation response after cessation of various exercise intensities identical interval training protocol.

4.
Cereb Cortex ; 34(1)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38061690

RESUMO

Post-tetanic Ca2+ release from mitochondria produces presynaptic residual calcium, which contributes to post-tetanic potentiation. The loss of mitochondria-dependent post-tetanic potentiation is one of the earliest signs of Alzheimer's model mice. Post-tetanic potentiation at intracortical synapses of medial prefrontal cortex has been implicated in working memory. Although mitochondrial contribution to post-tetanic potentiation differs depending on synapse types, it is unknown which synapse types express mitochondria-dependent post-tetanic potentiation in the medial prefrontal cortex. We studied expression of mitochondria-dependent post-tetanic potentiation at different intracortical synapses of the rat medial prefrontal cortex. Post-tetanic potentiation occurred only at intracortical synapses onto layer 5 corticopontine cells from commissural cells and L2/3 pyramidal neurons. Among post-tetanic potentiation-expressing synapses, L2/3-corticopontine synapses in the prelimbic cortex were unique in that post-tetanic potentiation depends on mitochondria because post-tetanic potentiation at corresponding synapse types in other cortical areas was independent of mitochondria. Supporting mitochondria-dependent post-tetanic potentiation at L2/3-to-corticopontine synapses, mitochondria-dependent residual calcium at the axon terminals of L2/3 pyramidal neurons was significantly larger than that at commissural and corticopontine cells. Moreover, post-tetanic potentiation at L2/3-corticopontine synapses, but not at commissural-corticopontine synapses, was impaired in the young adult Alzheimer's model mice. These results would provide a knowledge base for comprehending synaptic mechanisms that underlies the initial clinical signs of neurodegenerative disorders.


Assuntos
Doença de Alzheimer , Ratos , Camundongos , Animais , Doença de Alzheimer/metabolismo , Cálcio/metabolismo , Sinapses/fisiologia , Mitocôndrias/metabolismo , Córtex Pré-Frontal/metabolismo , Potenciação de Longa Duração/fisiologia , Plasticidade Neuronal/fisiologia
5.
Front Mol Neurosci ; 16: 1175522, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37664244

RESUMO

Huntington's disease (HD) is a progressive dominantly inherited neurodegenerative disease caused by the expansion of a cytosine-adenine-guanine (CAG) trinucleotide repeat in the huntingtin gene, which encodes the mutant huntingtin protein containing an expanded polyglutamine tract. One of neuropathologic hallmarks of HD is selective degeneration in the striatum. Mechanisms underlying selective neurodegeneration in the striatum of HD remain elusive. Neurodegeneration is suggested to be preceded by abnormal synaptic transmission at the early stage of HD. However, how mutant huntingtin protein affects synaptic vesicle exocytosis at single presynaptic terminals of HD striatal neurons is poorly understood. Here, we measured synaptic vesicle exocytosis at single presynaptic terminals of cultured striatal neurons (mainly inhibitory neurons) in a knock-in mouse model of HD (zQ175) during electrical field stimulation using real-time imaging of FM 1-43 (a lipophilic dye). We found a significant decrease in bouton density and exocytosis of synaptic vesicles at single presynaptic terminals in cultured striatal neurons. Real-time imaging of VGAT-CypHer5E (a pH sensitive dye conjugated to an antibody against vesicular GABA transporter (VGAT)) for inhibitory synaptic vesicles revealed a reduction in bouton density and exocytosis of inhibitory synaptic vesicles at single presynaptic terminals of HD striatal neurons. Thus, our results suggest that the mutant huntingtin protein decreases bouton density and exocytosis of inhibitory synaptic vesicles at single presynaptic terminals of striatal neurons, causing impaired inhibitory synaptic transmission, eventually leading to the neurodegeneration in the striatum of HD.

6.
Integr Med Res ; 12(2): 100949, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37214317

RESUMO

Background: Accelerated skeletal muscle wasting is a shared trait among many pathologies and aging. Acupuncture has been used as a therapeutic intervention to control pain; however, little is known about its effects on skeletal muscle atrophy and function. The study's purpose was to compare the effects of acupuncture, electro-acupuncture, and electrical stimulation on cast-induced skeletal muscle atrophy. Methods: Forty female Sprague Dawley rats were randomly divided into groups: Control, casted (CAST), CAST+Acupuncture (CAST-A), 4) CAST+Electro-acupuncture (CAST-EA), and CAST+Electrical stimulation (CAST-ES) (n = 8). Plaster casting material was wrapped around the left hind limb. Acupuncture and electro-acupuncture (10 Hz, 6.4 mA) treatments were applied by needling acupoints (stomach-36 and gallbladder-34). Electrical stimulation (10 Hz, 6.4 mA) was conducted by needling the lateral and medial gastrocnemius muscles. Treatments were conducted for 15 min, three times/week for 14 days. Muscle atrophy F-box (MAFbx), muscle RING finger 1 (MuRF1), and contractile properties were assessed. Results: Fourteen days of cast-immobilization decreased muscle fiber CSA by 56% in the CAST group (p = 0.00); whereas, all treatment groups demonstrated greater muscle fiber CSA than the CAST group (p = 0.00). Cast-immobilization increased MAFbx and MuRF1 protein expression in the CAST group (p<0.01) while the CAST-A, CAST-EA, and CAST-ES groups demonstrated lower levels of MAFbx and MuRF1 protein expression (p<0.02) compared to the CAST group. Following fourteen days of cast-immobilization, peak twitch tension did not differ between the CAST-A and CON groups (p = 0.12). Conclusion: Skeletal muscle atrophy, induced by 14 days of cast-immobilization, was significantly attenuated by acupuncture, electro-acupuncture, or electrical stimulation.

7.
Mol Brain ; 16(1): 45, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-37217996

RESUMO

High frequency burst firing is critical in summation of back-propagating action potentials (APs) in dendrites, which may greatly depolarize dendritic membrane potential. The physiological significance of burst firings of hippocampal dentate GCs in synaptic plasticity remains unknown. We found that GCs with low input resistance could be categorized into regular-spiking (RS) and burst-spiking (BS) cells based on their initial firing frequency (Finit) upon somatic rheobase current injection, and investigated how two types of GCs differ in long-term potentiation (LTP) induced by high-frequency lateral perforant pathway (LPP) inputs. Induction of Hebbian LTP at LPP synapses required at least three postsynaptic APs at Finit higher than 100 Hz, which was met in BS but not in RS cells. The synaptically evoked burst firing was critically dependent on persistent Na+ current, which was larger in BS than RS cells. The Ca2+ source for Hebbian LTP at LPP synapses was primarily provided by L-type calcium channels. In contrast, Hebbian LTP at medial PP synapses was mediated by T-type calcium channels, and could be induced regardless of cell types or Finit of postsynaptic APs. These results suggest that intrinsic firing properties affect synaptically driven firing patterns, and that bursting behavior differentially affects Hebbian LTP mechanisms depending on the synaptic input pathway.


Assuntos
Potenciação de Longa Duração , Via Perfurante , Potenciação de Longa Duração/fisiologia , Via Perfurante/fisiologia , Hipocampo/fisiologia , Neurônios/fisiologia , Sinapses/fisiologia , Giro Denteado/fisiologia
8.
Proc Natl Acad Sci U S A ; 120(12): e2220649120, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36920925

RESUMO

Subthreshold depolarization enhances neurotransmitter release evoked by action potentials and plays a key role in modulating synaptic transmission by combining analog and digital signals. This process is known to be Ca2+ dependent. However, the underlying mechanism of how small changes in basal Ca2+ caused by subthreshold depolarization can regulate transmitter release triggered by a large increase in local Ca2+ is not well understood. This study aimed to investigate the source and signaling mechanisms of Ca2+ that couple subthreshold depolarization with the enhancement of glutamate release in hippocampal cultures and CA3 pyramidal neurons. Subthreshold depolarization increased presynaptic Ca2+ levels, the frequency of spontaneous release, and the amplitude of evoked release, all of which were abolished by blocking L-type Ca2+ channels. A high concentration of intracellular Ca2+ buffer or blockade of calmodulin abolished depolarization-induced increases in transmitter release. Estimation of the readily releasable pool size using hypertonic sucrose showed depolarization-induced increases in readily releasable pool size, and this increase was abolished by the blockade of calmodulin. Our results provide mechanistic insights into the modulation of transmitter release by subthreshold potential change and highlight the role of L-type Ca2+ channels in coupling subthreshold depolarization to the activation of Ca2+-dependent signaling molecules that regulate transmitter release.


Assuntos
Canais de Cálcio Tipo L , Cálcio , Potenciais Evocados , Ácido Glutâmico , Potenciais da Membrana , Canais de Cálcio Tipo L/metabolismo , Ácido Glutâmico/metabolismo , Calmodulina/metabolismo , Cálcio/metabolismo , Terminações Pré-Sinápticas/metabolismo , Neurotransmissores/metabolismo , Animais , Ratos , Células Cultivadas , Hipocampo/citologia , Neurônios/metabolismo , Ratos Sprague-Dawley , Transmissão Sináptica
9.
Biol Psychiatry ; 94(5): 378-392, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36906501

RESUMO

BACKGROUND: Unbalanced activity of medium spiny neurons (MSNs) of the direct and indirect pathways mediates reward-related behaviors induced by addictive drugs. Prelimbic (PL) input to MSNs in the nucleus accumbens core (NAcC) plays a key role in cocaine-induced early locomotor sensitization (LS). However, the adaptive plastic changes at PL-to-NAcC synapses underlying early LS remain unclear. METHODS: Using transgenic mice and retrograde tracing, we identified NAcC-projecting pyramidal neurons (PNs) in the PL cortex based on the expression of dopamine receptor types (D1R or D2R). To examine cocaine-induced alterations in PL-to-NAcC synapses, we measured excitatory postsynaptic current amplitudes evoked by optostimulation of PL afferents to MSNs. Riluzole was chosen to test the effects of PL excitability on cocaine-induced changes of PL-to-NAcC synapses. RESULTS: NAcC-projecting PNs were segregated into D1R- and D2R-expressing PNs (D1- and D2-PNs, respectively), and their excitability was opposingly regulated by respective dopamine agonists. Both D1- and D2-PNs exhibited balanced innervation of direct MSNs and indirect MSNs in naïve animals. Repeated cocaine injections resulted in biased synaptic strength toward direct MSNs through presynaptic mechanisms in both D1- and D2-PNs, although D2R activation reduced the D2-PN excitability. Under group 1 metabotropic glutamate receptors coactivation, however, D2R activation enhanced the D2-PN excitability. The cocaine-induced rewiring accompanied LS, and both rewiring and LS were precluded by PL infusion of riluzole, which reduced the intrinsic excitability of PL neurons. CONCLUSIONS: These findings indicate that cocaine-induced rewiring of PL-to-NAcC synapses correlates well with early behavioral sensitization and that rewiring and LS can be prevented by riluzole-induced reduction of excitability of PL neurons.


Assuntos
Cocaína , Camundongos , Animais , Cocaína/farmacologia , Cocaína/metabolismo , Núcleo Accumbens , Riluzol/metabolismo , Riluzol/farmacologia , Receptores de Dopamina D2/metabolismo , Camundongos Transgênicos , Receptores de Dopamina D1/metabolismo
10.
Adv Mater ; 35(4): e2203481, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35953281

RESUMO

A new type of atomically thin synaptic network on van der Waals (vdW) heterostructures is reported, where each ultrasmall cell (≈2 nm thick) built with trilayer WS2 semiconductor acts as a gate-tunable photoactive synapse, i.e., a photo-memtransistor. A train of UV pulses onto the WS2 memristor generates dopants in atomic-level precision by direct light-lattice interactions, which, along with the gate tunability, leads to the accurate modulation of the channel conductance for potentiation and depression of the synaptic cells. Such synaptic dynamics can be explained by a parallel atomistic resistor network model. In addition, it is shown that such a device scheme can generally be realized in other 2D vdW semiconductors, such as MoS2 , MoSe2 , MoTe2 , and WSe2 . Demonstration of these atomically thin photo-memtransistor arrays, where the synaptic weights can be tuned for the atomistic defect density, provides implications for a new type of artificial neural networks for parallel matrix computations with an ultrahigh integration density.

11.
Int J Exerc Sci ; 15(3): 1563-1577, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36583141

RESUMO

The purpose of this study was to analyze how blood flow restriction (BFR) training influences muscular strength through a systematic review and meta-analysis. The review was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. The following databases were used to conduct the research: Academic Search Complete, Medline, Web of Science, SPORT-Discus, HealthSource: Consumer, and HealthSource: Nursing. The following search limitations were included in this study: full-text articles investigating the effects of BFR training on muscular strength, published in a peer-reviewed academic journal, and published in the English language. Out of 327 articles, 25 were eligible to be included in this study. Comprehensive meta-analysis v.3 software was used to run statistics of the collected data from each study. The results showed that BFR training positively affects muscular strength. However, no group difference was found by gender, duration, workload, and cuff type/pressure in current data. This study provides additional information that can be used in future studies to obtain optimum strength results during BFR training.

12.
Small ; 18(34): e2106629, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35905492

RESUMO

Nanostructured copper selenide (Cu2 Se) attracts much interest as it shows outstanding performance as thermoelectric, photo-thermal, and optical material. The mesoporous structure is also a promising morphology to obtain better performance for electrochemical and catalytic applications, thanks to its high surface area. A simple one-step electrochemical method is proposed for mesoporous chalcogenides synthesis. The synthesized Cu2 Se material has two types of mesopores (9 and 18 nm in diameter), which are uniformly distributed inside the flakes. These materials are also implemented for sodium (Na) ion battery (NIB) anode as a proof of concept. The electrode employing the mesoporous Cu2 Se exhibits superior and more stable specific capacity as a NIB anode compared to the non-porous samples. The electrode also exhibits excellent rate tolerance at each current density, from 100 to 1000 mA g-1 . It is suggested that the mesoporous structure is advantageous for the insertion of Na ions inside the flakes. Electrochemical analysis indicates that the mesoporous electrode possesses more prominent diffusion-controlled kinetics during the sodiation-desodiation process, which contributes to the improvement of Na-ion storage performance.

13.
Rheumatol Ther ; 9(4): 1157-1169, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35776269

RESUMO

INTRODUCTION: SB5 is an approved biosimilar of adalimumab, a monoclonal anti-tumor necrosis factor (anti-TNF) antibody. This study compared pharmacokinetics (PK), safety, tolerability, and immunogenicity between a new high-concentration, low-volume, and citrate-free formulation (40 mg/0.4 ml, SB5-HC) and the current low-concentration formulation with higher volume (40 mg/0.8 ml, SB5-LC) to evaluate the bioequivalence of the two formulations. METHODS: This study was a randomized, single-blind, two-arm, parallel-group, single-dose study in healthy male subjects. Subjects were randomized to receive either SB5-HC or SB5-LC via subcutaneous injection using a pre-filled syringe. Primary endpoints were the area under the curve of the concentration-time curve from zero to infinity (AUCinf) and maximum serum concentration (Cmax). Bioequivalence was achieved if the 90% confidence intervals (CIs) for the ratios of the geometric least squares mean (LSMean) of primary endpoints were within the pre-defined bioequivalence margins of 0.80-1.25. Secondary endpoints included safety, tolerability, and immunogenicity. RESULTS: Subjects (n = 188) were randomized to SB5-HC (n = 94) or SB5-LC (n = 94). Baseline characteristics were comparable between the two treatment groups. The mean values for AUCinf and Cmax were similar between the SB5-HC and SB5-LC groups. For the primary endpoints, the geometric LSMean ratios (90% CI) for AUCinf and Cmax were 0.920 (0.8262-1.0239) and 0.984 (0.9126-1.0604), respectively, placing the corresponding 90% CIs well within the pre-defined bioequivalence margin of 0.80-1.25. All treatment-emergent adverse events (TEAEs) were considered mild to moderate and were reported for 44.7% and 51.1% of subjects in the SB5-HC and SB5-LC groups, respectively. Immunogenicity assessed by frequency of occurrence of anti-drug antibodies (ADAs) and neutralizing antibodies (NAbs) was comparable between groups. CONCLUSIONS: This bridging study demonstrated PK equivalence and comparable safety and tolerability of subcutaneous injection of SB5 via SB5-HC or SB5-LC. CLINICALTRIALS: GOV IDENTIFIER: https://clinicaltrials.gov/ct2/show/NCT04514796 .

14.
Sensors (Basel) ; 22(5)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35270912

RESUMO

In this paper, we propose a deep-image-prior-based demosaicing method for a random RGBW color filter array (CFA). The color reconstruction from the random RGBW CFA is performed by the deep image prior network, which uses only the RGBW CFA image as the training data. To our knowledge, this work is a first attempt to reconstruct the color image with a neural network using only a single RGBW CFA in the training. Due to the White pixels in the RGBW CFA, more light is transmitted through the CFA than in the case with the conventional RGB CFA. As the image sensor can detect more light, the signal-to-noise-ratio (SNR) increases and the proposed demosaicing method can reconstruct the color image with a higher visual quality than other existing demosaicking methods, especially in the presence of noise. We propose a loss function that can train the deep image prior (DIP) network to reconstruct the colors from the White pixels as well as from the red, green, and blue pixels in the RGBW CFA. Apart from using the DIP network, no additional complex reconstruction algorithms are required for the demosaicing. The proposed demosaicing method becomes useful in situations when the noise becomes a major problem, for example, in low light conditions. Experimental results show the validity of the proposed method for joint demosaicing and denoising.

15.
Exp Neurobiol ; 31(6): 361-375, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36631845

RESUMO

Dopaminergic projection to the hippocampus from the ventral tegmental area or locus ceruleus has been considered to play an essential role in the acquisition of novel information. Hence, the dopaminergic modulation of synaptic plasticity in the hippocampus has been widely studied. We examined how the D1 and D2 receptors influenced the mGluR5-mediated synaptic plasticity of the temporoammonic-CA1 synapses and showed that the dopaminergic modulation of the temporoammonic-CA1 synapses was expressed in various ways. Our findings suggest that the dopaminergic system in the hippocampal CA1 region regulates the long-term synaptic plasticity and processing of the novel information.

16.
Hippocampus ; 32(3): 193-216, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34964210

RESUMO

The associative network of hippocampal CA3 is thought to contribute to rapid formation of contextual memory from one-trial learning, but the network mechanisms underlying decorrelation of neuronal ensembles in CA3 is largely unknown. Kv1.2 expressions in rodent CA3 pyramidal cells (CA3-PCs) are polarized to distal apical dendrites, and its downregulation specifically enhances dendritic responses to perforant pathway (PP) synaptic inputs. We found that haploinsufficiency of Kv1.2 (Kcna2+/-) in CA3-PCs, but not Kv1.1 (Kcna1+/-), lowers the threshold for long-term potentiation (LTP) at PP-CA3 synapses, and that the Kcna2+/- mice are normal in discrimination of distinct contexts but impaired in discrimination of similar but slightly distinct contexts. We further examined the neuronal ensembles in CA3 and dentate gyrus (DG), which represent the two similar contexts using in situ hybridization of immediate early genes, Homer1a and Arc. The size and overlap of CA3 ensembles activated by the first visit to the similar contexts were not different between wild type and Kcna2+/- mice, but these ensemble parameters diverged over training days between genotypes, suggesting that abnormal plastic changes at PP-CA3 synapses of Kcna2+/- mice is responsible for the impaired pattern separation. Unlike CA3, DG ensembles were not different between two genotype mice. The DG ensembles were already separated on the first day, and their overlap did not further evolve. Eventually, the Kcna2+/- mice exhibited larger CA3 ensemble size and overlap upon retrieval of two contexts, compared to wild type or Kcna1+/- mice. These results suggest that sparse LTP at PP-CA3 synapse probably supervised by mossy fiber inputs is essential for gradual decorrelation of CA3 ensembles.


Assuntos
Aprendizagem por Discriminação , Fibras Musgosas Hipocampais , Animais , Potenciação de Longa Duração/fisiologia , Camundongos , Fibras Musgosas Hipocampais/fisiologia , Via Perfurante , Células Piramidais/fisiologia , Sinapses/fisiologia
17.
Prog Neurobiol ; 208: 102182, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34695543

RESUMO

Neurotransmitter release occurs either synchronously with action potentials (evoked release) or spontaneously (spontaneous release). Whether the molecular mechanisms underlying evoked and spontaneous release are identical, especially whether voltage-gated calcium channels (VGCCs) can trigger spontaneous events, is still a matter of debate in glutamatergic synapses. To elucidate this issue, we characterized the VGCC dependence of miniature excitatory postsynaptic currents (mEPSCs) in various synapses with different coupling distances between VGCCs and synaptic vesicles, known as a critical factor in evoked release. We found that most of the extracellular calcium-dependent mEPSCs were attributable to VGCCs in cultured autaptic hippocampal neurons and the mature calyx of Held where VGCCs and vesicles were tightly coupled. Among loosely coupled synapses, mEPSCs were not VGCC-dependent at immature calyx of Held and CA1 pyramidal neuron synapses, whereas VGCCs contribution was significant at CA3 pyramidal neuron synapses. Interestingly, the contribution of VGCCs to spontaneous glutamate release in CA3 pyramidal neurons was abolished by a calmodulin antagonist, calmidazolium. These data suggest that coupling distance between VGCCs and vesicles determines VGCC dependence of spontaneous release at tightly coupled synapses, yet VGCC contribution can be achieved indirectly at loosely coupled synapses.


Assuntos
Calmodulina , Ácido Glutâmico , Cálcio/metabolismo , Canais de Cálcio , Potenciais Pós-Sinápticos Excitadores/fisiologia , Humanos , Sinapses/metabolismo
18.
Sensors (Basel) ; 21(21)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34770365

RESUMO

Wearable technologies are known to improve our quality of life. Among the various wearable devices, shoes are non-intrusive, lightweight, and can be used for outdoor activities. In this study, we estimated the energy consumption and heart rate in an environment (i.e., running on a treadmill) using smart shoes equipped with triaxial acceleration, triaxial gyroscope, and four-point pressure sensors. The proposed model uses the latest deep learning architecture which does not require any separate preprocessing. Moreover, it is possible to select the optimal sensor using a channel-wise attention mechanism to weigh the sensors depending on their contributions to the estimation of energy expenditure (EE) and heart rate (HR). The performance of the proposed model was evaluated using the root mean squared error (RMSE), mean absolute error (MAE), and coefficient of determination (R2). Moreover, the RMSE was 1.05 ± 0.15, MAE 0.83 ± 0.12 and R2 0.922 ± 0.005 in EE estimation. On the other hand, and RMSE was 7.87 ± 1.12, MAE 6.21 ± 0.86, and R2 0.897 ± 0.017 in HR estimation. In both estimations, the most effective sensor was the z axis of the accelerometer and gyroscope sensors. Through these results, it is demonstrated that the proposed model could contribute to the improvement of the performance of both EE and HR estimations by effectively selecting the optimal sensors during the active movements of participants.


Assuntos
Aprendizado Profundo , Sapatos , Metabolismo Energético , Frequência Cardíaca , Humanos , Qualidade de Vida
19.
Int Neurourol J ; 25(Suppl 2): S47-54, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34844386

RESUMO

PURPOSE: The effects of aerobic exercise training on soleus muscle morphology, mitochondria-mediated apoptotic signaling, and atrophy/hypertrophy signaling in ovariectomized rat skeletal muscle were investigated. METHODS: Female Sprague-Dawley rats were divided into control (CON), ovariectomy (OVX), and ovariectomy plus exercise (OVX+EX) groups. After ovarian excision, exercise training was performed using a rat treadmill at 20 m/min, 50 min/day, 5 days/week for 12 weeks. Protein levels of mitochondria-mediated apoptotic signaling and atrophy/hypertrophy signaling in the skeletal muscle (soleus) were examined through western immunoblot analysis. RESULTS: The number of myocytes and myocyte cross-sectional area (CSA) were increased and the extramyocyte space was decreased in the OVX group compared to those in the CON group. However, aerobic exercise training significantly increased myocyte CSA and decreased extramyocyte space in the OVX+EX group compared to those in the OVX group. The protein levels of proapoptotic signaling and muscle atrophy signaling were significantly increased, whereas the protein levels of muscle hypertrophy signaling were significantly decreased in the OVX group compared to that in the CON group. Aerobic exercise training significantly decreased the protein levels of proapoptotic signaling and increased the protein level of antiapoptotic protein in the OVX+EX group compared to that in the OVX group. Aerobic exercise training significantly increased the protein levels of hypertrophy signaling and decreased protein levels of atrophy signaling in the OVX+EX group compared to those in the OVX group. CONCLUSION: Treadmill exercise improved estrogen deficiency-induced impairment in skeletal muscle remodeling, mitochondria-mediated apoptotic signaling, and atrophy/hypertrophy signaling in skeletal muscle.

20.
Nat Nanotechnol ; 16(10): 1092-1098, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34267369

RESUMO

A broad range of transition metal dichalcogenide (TMDC) semiconductors are available as monolayer (ML) crystals, so the precise integration of each kind into van der Waals (vdW) superlattices (SLs) could enable the realization of novel structures with previously unexplored functionalities. Here we report the atomic layer-by-layer epitaxial growth of vdW SLs with programmable stacking periodicities, composed of more than two kinds of dissimilar TMDC MLs, such as MoS2, WS2 and WSe2. Using kinetics-controlled vdW epitaxy in the near-equilibrium limit by metal-organic chemical vapour depositions, we achieved precise ML-by-ML stacking, free of interlayer atomic mixing, which resulted in tunable two-dimensional vdW electronic systems. As an example, by exploiting the series of type II band alignments at coherent two-dimensional vdW heterointerfaces, we demonstrated valley-polarized carrier excitations-one of the most distinctive electronic features in vdW ML semiconductors-which scale with the stack numbers n in our (MoS2/WS2)n SLs on optical excitations.

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