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1.
Cell ; 162(3): 593-606, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26213384

RESUMO

α- and ß-neurexins are presynaptic cell-adhesion molecules implicated in autism and schizophrenia. We find that, although ß-neurexins are expressed at much lower levels than α-neurexins, conditional knockout of ß-neurexins with continued expression of α-neurexins dramatically decreased neurotransmitter release at excitatory synapses in cultured cortical neurons. The ß-neurexin knockout phenotype was attenuated by CB1-receptor inhibition, which blocks presynaptic endocannabinoid signaling, or by 2-arachidonoylglycerol synthesis inhibition, which impairs postsynaptic endocannabinoid release. In synapses formed by CA1-region pyramidal neurons onto burst-firing subiculum neurons, presynaptic in vivo knockout of ß-neurexins aggravated endocannabinoid-mediated inhibition of synaptic transmission and blocked LTP; presynaptic CB1-receptor antagonists or postsynaptic 2-arachidonoylglycerol synthesis inhibition again reversed this block. Moreover, conditional knockout of ß-neurexins in CA1-region neurons impaired contextual fear memories. Thus, our data suggest that presynaptic ß-neurexins control synaptic strength in excitatory synapses by regulating postsynaptic 2-arachidonoylglycerol synthesis, revealing an unexpected role for ß-neurexins in the endocannabinoid-dependent regulation of neural circuits.


Assuntos
Endocanabinoides/metabolismo , Moléculas de Adesão de Célula Nervosa/metabolismo , Vias Neurais/metabolismo , Sinapses/metabolismo , Animais , Ácidos Araquidônicos/biossíntese , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio , Endocanabinoides/biossíntese , Glicerídeos/biossíntese , Hipocampo/citologia , Hipocampo/metabolismo , Camundongos , Camundongos Knockout , Moléculas de Adesão de Célula Nervosa/genética , Neurônios/metabolismo , Neurotransmissores/metabolismo , Transdução de Sinais
2.
Proc Natl Acad Sci U S A ; 120(13): e2300363120, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36961922

RESUMO

α- and ß-neurexins are extensively alternatively spliced, presynaptic cell-adhesion molecules that are thought to organize synapse assembly. However, recent data revealed that, in the hippocampus in vivo, the deletion of one neurexin isoform, Nrxn2, surprisingly increased excitatory synapse numbers and enhanced their presynaptic release probability, suggesting that Nrxn2 restricts, instead of enabling, synapse assembly. To delineate the synaptic function and mechanism of action of Nrxn2, we examined cultured hippocampal neurons as a reduced system. In heterologous synapse formation assays, different alternatively spliced Nrxn2ß isoforms robustly promoted synapse assembly similar to Nrxn1ß and Nrxn3ß, consistent with a general synaptogenic function of neurexins. Deletion of Nrxn2 from cultured hippocampal neurons, however, caused a significant increase in synapse density and release probability, replicating the in vivo data that suggested a synapse-restricting function. Rescue experiments revealed that two of the four Nrxn2ß splice variants (Nrxn2ß-SS4+/SS5- and Nrxn2ß-SS4+/SS5+) reversed the increase in synapse density in Nrxn2-deficient neurons, whereas only one of the four Nrxn2ß splice variants (Nrxn2ß-SS4+/SS5+) normalized the increase in release probability in Nrxn2-deficient neurons. Thus, a subset of Nrxn2 splice variants restricts synapse numbers and restrains their release probability in cultured neurons.


Assuntos
Processamento Alternativo , Sinapses , Sinapses/metabolismo , Hipocampo/metabolismo , Moléculas de Adesão Celular/metabolismo , Neurônios/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Moléculas de Adesão de Célula Nervosa/genética , Moléculas de Adesão de Célula Nervosa/metabolismo
3.
Cell ; 141(6): 1068-79, 2010 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-20537373

RESUMO

Elucidation of molecular mechanisms that regulate synapse formation is required for the understanding of neural wiring, higher brain functions, and mental disorders. Despite the wealth of in vitro information, fundamental questions about how glutamatergic synapses are formed in the mammalian brain remain unanswered. Glutamate receptor (GluR) delta2 is essential for cerebellar synapse formation in vivo. Here, we show that the N-terminal domain (NTD) of GluRdelta2 interacts with presynaptic neurexins (NRXNs) through cerebellin 1 precursor protein (Cbln1). The synaptogenic activity of GluRdelta2 is abolished in cerebellar primary cultures from Cbln1 knockout mice and is restored by recombinant Cbln1. Knockdown of NRXNs in cerebellar granule cells also hinders the synaptogenic activity of GluRdelta2. Both the NTD of GluRdelta2 and the extracellular domain of NRXN1beta suppressed the synaptogenic activity of Cbln1 in cerebellar primary cultures and in vivo. These results suggest that GluRdelta2 mediates cerebellar synapse formation by interacting with presynaptic NRXNs through Cbln1.


Assuntos
Cerebelo/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Moléculas de Adesão de Célula Nervosa/metabolismo , Precursores de Proteínas/metabolismo , Receptores de Glutamato/metabolismo , Sinapses , Animais , Proteínas de Ligação ao Cálcio , Linhagem Celular , Células Cultivadas , Humanos , Camundongos
4.
Proc Natl Acad Sci U S A ; 119(20): e2123421119, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35544694

RESUMO

Five decades ago, long-term potentiation (LTP) of synaptic transmission was discovered at entorhinal cortex→dentate gyrus (EC→DG) synapses, but the molecular determinants of EC→DG LTP remain largely unknown. Here, we show that the presynaptic neurexin­ligand cerebellin-4 (Cbln4) is highly expressed in the entorhinal cortex and essential for LTP at EC→DG synapses, but dispensable for basal synaptic transmission at these synapses. Cbln4, when bound to cell-surface neurexins, forms transcellular complexes by interacting with postsynaptic DCC (deleted in colorectal cancer) or neogenin-1. DCC and neogenin-1 act as netrin and repulsive guidance molecule-a (RGMa) receptors that mediate axon guidance in the developing brain, but their binding to Cbln4 raised the possibility that they might additionally function in the mature brain as postsynaptic receptors for presynaptic neurexin/Cbln4 complexes, and that as such receptors, DCC or neogenin-1 might mediate EC→DG LTP that depends on Cbln4. Indeed, we observed that neogenin-1, but not DCC, is abundantly expressed in dentate gyrus granule cells, and that postsynaptic neogenin-1 deletions in dentate granule cells blocked EC→DG LTP, but again did not affect basal synaptic transmission similar to the presynaptic Cbln4 deletions. Thus, binding of presynaptic Cbln4 to postsynaptic neogenin-1 renders EC→DG synapses competent for LTP, but is not required for establishing these synapses or for otherwise enabling their function.


Assuntos
Giro Denteado , Potenciação de Longa Duração , Proteínas de Membrana , Proteínas do Tecido Nervoso , Precursores de Proteínas , Sinapses , Transmissão Sináptica , Animais , Giro Denteado/metabolismo , Ligantes , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/metabolismo , Receptores de Netrina/metabolismo , Precursores de Proteínas/metabolismo , Sinapses/metabolismo
5.
Langmuir ; 39(19): 6740-6747, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37130261

RESUMO

Recently, miraculous therapy approaches involving adeno-associated virus (AAV) for incurable diseases such as spinal muscular atrophy and inherited retinal dysfunction have been introduced. Nonreplicative, nonpathogenic, low rates of chromosome insertional properties and the existence of neutralizing antibodies are main safety reasons why the FDA approved its use in gene delivery. To date, AAV production always results in a mixture of nontherapeutic (empty) and therapeutic (DNA-loaded) full capsids (10-98%). Such existence of empty viral particles inevitably increases viral doses to human. Thus, the rapid monitoring of empty capsids and reducing the empty-to-full ratio are critical in AAV science. However, transmission electron microscopy (TEM) is the primary tool for distinguishing between empty and full capsids, which creates a research bottleneck because of instrument accessibility and technical difficulty. Herein, we demonstrate that atomic force microscopy (AFM) can be an alternative tool to TEM. The simple, noncontact-mode imaging of AAV particles allows the distinct height difference between full capsids (∼22 nm) and empty capsids (∼16 nm). The sphere-to-ellipsoidal morphological distortion observed for empty AAV particles clearly distinguishes them from full AAV particles. Our study indicates that AFM imaging can be an extremely useful, quality-control tool in AAV particle monitoring, which is beneficial for the future development of AAV-based gene therapy.


Assuntos
Capsídeo , Dependovirus , Humanos , Dependovirus/genética , Microscopia de Força Atômica , Vetores Genéticos , DNA
6.
Medicina (Kaunas) ; 59(1)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36676801

RESUMO

Background and objectives: EG-Mirotin (active ingredient EGT022) targets nonproliferative diabetic retinopathy (NPDR), the early stage of retinopathy. EG-Mirotin reverses capillary damage before NPDR progresses to an irreversible stage. EG-Mirotin safety and efficacy were investigated in patients with type 1 or type 2 diabetes mellitus and moderate to severe NPDR. Methods: In this open-label, single-arm, single-center, exploratory phase II study, 10 patients (20 eyes) received EG-Mirotin once a day (3 mg/1.5 mL sterile saline) for 5 days and were evaluated for ischemic index changes and safety. End of study was approximately 8 ± 1 weeks (57 ± 7 days) after the first drug administration. Results: EG-Mirotin injections were well tolerated, with no dose-limiting adverse events, serious adverse events, or deaths. Four treatment-emergent adverse events (TEAEs) unrelated to the investigational drug were observed in 2 out of 10 participants (20%) who had received the investigational drug. The overall average percent change in ischemic index at each evaluation point compared with baseline was statistically significant (Greenhouse-Geisser F = 9.456, p = 0.004 for the main effect of time), and a larger change was observed when the baseline ischemic index value was high (Greenhouse-Geisser F = 10.946, p = 0.002 for time × group interaction). Conclusions: The EG-Mirotin regimen established in this study was shown to be feasible and safe and was associated with a trend toward potential improvement in diabetes-induced ischemia and retinal capillary leakage.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Preparações Farmacêuticas , Drogas em Investigação/uso terapêutico , Angiofluoresceinografia , Peptídeos/uso terapêutico
7.
Plant Dis ; 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35939751

RESUMO

Mume virus A (MuVA) of the genus Capillovirus in the family Betaflexiviridae was first isolated from a Japanese apricot tree (Prunus mume) exhibiting symptoms of diffuse chlorotic spots (Marais et al. 2018). MuVA infection has been reported in Japanese apricot trees in Japan as well as in peach (P. persica) and Japanese apricot trees in China (Marais et al. 2018; Zhang et al. 2021; Zheng et al. 2020). In the present study, the diversity of viruses and viroids infecting Chinese plum trees (P. salicina) was investigated using high-throughput sequencing (HTS). Ten flowers each from 50 trees without obvious symptoms related to virus and/or viroid infection were randomly collected from five orchards in Gimcheon, Korea, in April 2020. The samples from each Chinese plum tree were pooled, and the same amounts of 50 individual samples prepared in advance were pooled for the extraction of total RNA using the RNeasy Plant Mini Kit (QIAGEN, Hilden, Germany). Removal of ribosomal RNA and construction of cDNA library from the extracted total RNA were conducted using the TruSeq Stranded Total RNA with Ribo-Zero Plant kit (Illumina, San Diego, CA, USA). Paired-end RNA sequencing using Illumina NovaSeq 6000 System (paired-end reads of 101 bp and a total of 162,845,322 reads) and data analysis were performed at Macrogen (Daejeon, Korea). Adaptor and low-quality sequences of reads were removed using Trimmomatic program. Trimmed reads were assembled into contigs using Trinity program, and several databases including NCBI Nucleotide and Kyoto Encyclopedia of Genes and Genomes were used for functional annotation. HTS identified plum bark necrosis stem pitting-associated virus (PBNSPaV; four contigs ranging from 2081 to 3202 nucleotides) and hop stunt viroid (HSVd; one contig of 618 nucleotides). PBNSPaV and HSVd were also detected by RT-PCR (PBNSPaV det-F and PBNSPaV det-R for PBNSPaV [Al Rwahnih et al. 2007]; VP-19 and VP-20 for HSVd [Astruc et al. 1996]) and confirmed by Sanger sequencing of the amplified products. Interestingly, one contig derived from MuVA, which was not previously reported in Korea, was also detected. The contig was 7,618-nucleotide long (15,205 reads), and NCBI BLASTN search revealed 98.74% homology (100% query coverage) with the MuVA isolate pm14 (GenBank accession number MG783575). To design diagnostic primers for reverse transcription (RT)-polymerase chain reaction (PCR), the contig sequence and MuVA sequences available in NCBI GenBank (GenBank accession numbers MG783575 and MN412555) were aligned using CLC Main Workbench 6.9.1 (QIAGEN, Redwood, CA, USA). The following primer set (expected size of 1,143 bp) was prepared: MuVA-2F (5'-CAGCTTTGTGACTCYAACCC-3') and MuVA-2R (5'-AATGGCTTGAGGRCCTGCAG-3'). The primers target a partial region (nt position 1185 to 2327 on the basis of the reference genome sequence of MuVA, GenBank accession no. NC_040568) of the polyprotein gene (ORF1). Each of the 50 samples was tested for the presence of MuVA using the above-mentioned RT-PCR primers with SuPrimeScript RT-PCR Premix (GeNet Bio, Daejeon, Korea). MuVA was detected in three samples collected from the same orchard. The three amplicons were inserted into a T&A cloning vector (RBC Bioscience, Taipei, Taiwan) and sequenced at Macrogen. Three consensus sequences obtained by Sanger sequencing were registered in NCBI GenBank under accession numbers MW589492, MW589493, and MW589494. NCBI BLASTN search revealed that the Korean isolates of MuVA shared high homology with isolate pm14 [98.16%, 98.08%, and 98.16% (100% query coverage), respectively]. To confirm additional MuVA infections, leaf samples of Chinese plum trees were collected from orchards in Uiseong (70 trees) and Seongju (50 trees) as well as a Japanese apricot tree in Chuncheon, from April to July 2021. RT-PCR confirmed additional MuVA infections from Uiseong (one tree) and Seongju (one tree) as well as from the Japanese apricot tree in Chuncheon. NCBI BLASTN search of the three additional amplicons (GenBank accession numbers OM210030, OM210031, and OM210032) revealed high homology with isolate pm14 [98.25%, 98.08%, and 97.90% (100% query coverage)]. To the best of our knowledge, this is the first report of MuVA infecting P. mume in Korea and P. salicina worldwide. Further research is needed to investigate MuVA infections on various Prunus spp. including P. persica in Korea.

8.
Sensors (Basel) ; 21(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34770398

RESUMO

Multi-channel Impact-echo (IE) testing was used to evaluate debonding defects at the interface between track concrete layer, TCL, and hydraulically stabilized base course, HSB, in a real scale mockup model of concrete slab tracks for Korea high-speed railway (KHSR) system. The mockup model includes three debonding defects that were fabricated by inserting three 400 mm by 400 mm (length and width) thin plastic foam boards with three different thicknesses of 5 mm, 10 mm, and 15 mm, before casting concrete in TCL. Multi-channel IE signals obtained over solid concrete and debonding defects were reduced to three critical IE testing parameters (the velocity of concrete, peak frequency, and Q factor). Bilinear classification models were used to evaluate the individual and a combination of the characteristic parameters. It was demonstrated that the best evaluation performance was obtained by using average peak frequency or the combination of average peak frequency and average Q factor, obtained by eight accelerometers in the multi-channel IE device. The results and discussion in this study would improve the understanding of characteristics of multiple IE testing parameters in concrete slab tracks and provide a fundamental basis to develop an effective prediction model of non-destructive evaluation for debonding defects at the interface between TCL and HSB in concrete slab tracks.

9.
Sensors (Basel) ; 21(20)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34696088

RESUMO

The condition of the ballast is a critical factor affecting the riding quality and the performance of a track. Fouled ballast can accelerate track irregularities, which results in frequent ballast maintenance requirements. Severe fouling of the ballast can lead to track instability, an uncomfortable ride and, in the worst case, a derailment. In this regard, maintenance engineers perform routine track inspections to assess current and future ballast conditions. GPR has been used to assess the thickness and fouling levels of ballast. However, there are no potent procedures or specifications with which to determine the level of fouling. This research aims to develop a GPR analysis method capable of evaluating ballast fouling levels. Four ballast boxes were constructed with various levels of fouling. GPR testing was conducted using a GSSI (Geophysical Survey Systems, Inc.) device (400, 900, 1600 MHz), and a KRRI (Korea Railroad Research Institute) GPR device (500 MHz), which was developed for ballast tracks. The dielectric permittivity, scattering of the depth (thickness) values, signal strength at the ballast boundary, and area of the frequency spectrum were compared against the fouling level. The results show that as the fouling level increases, the former two variables increase while the latter two decrease. On the basis of these observations, a new integrated parameter, called a ballast condition scoring index (BCSI), is suggested. The BCSI was verified using field data. The results show that the BCSI has a strong correlation with the fouling level of the ballast and can be used as a fouling-level-indicating parameter.


Assuntos
Radar , República da Coreia
10.
J Loss Prev Process Ind ; 69: 104336, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33173256

RESUMO

The versatile and computationally attractive FATE™ facility software package for analyzing the transient behavior of facilities during normal and off-normal conditions is applied to the problem of SARS-CoV-2 virus transmission in single-and multi-room facilities. Subject to the justifiable assumptions of non-interacting virus droplets, room-wide spatially homogeneous virus droplet aerosols and droplet sedimentation in accordance with Stokes law; the FATE code tracks the virus aerosol from a human source through a facility with a practical ventilation system which reconditions, filters, and recycles the air. The results show that infection risk can be reduced by 50 percent for increased facility airflow, 70 percent for increased airflow and the inclusion of a HEPA filter on recirculated ventilation air, and nearly 90 percent for increased airflow, inclusion of a HEPA filter, and wearing a mask. These results clearly indicate that there are operational changes and engineering measures which can reduce the potential infection risk in multi-room facilities.

11.
Proc Natl Acad Sci U S A ; 114(7): E1253-E1262, 2017 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-28154140

RESUMO

Establishment, specification, and validation of synaptic connections are thought to be mediated by interactions between pre- and postsynaptic cell-adhesion molecules. Arguably, the best-characterized transsynaptic interactions are formed by presynaptic neurexins, which bind to diverse postsynaptic ligands. In a proteomic screen of neurexin-1 (Nrxn1) complexes immunoisolated from mouse brain, we identified carbonic anhydrase-related proteins CA10 and CA11, two homologous, secreted glycoproteins of unknown function that are predominantly expressed in brain. We found that CA10 directly binds in a cis configuration to a conserved membrane-proximal, extracellular sequence of α- and ß-neurexins. The CA10-neurexin complex is stable and stoichiometric, and results in formation of intermolecular disulfide bonds between conserved cysteine residues in neurexins and CA10. CA10 promotes surface expression of α- and ß-neurexins, suggesting that CA10 may form a complex with neurexins in the secretory pathway that facilitates surface transport of neurexins. Moreover, we observed that the Nrxn1 gene expresses from an internal 3' promoter a third isoform, Nrxn1γ, that lacks all Nrxn1 extracellular domains except for the membrane-proximal sequences and that also tightly binds to CA10. Our data expand the understanding of neurexin-based transsynaptic interaction networks by providing further insight into the interactions nucleated by neurexins at the synapse.


Assuntos
Encéfalo/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Moléculas de Adesão de Célula Nervosa/metabolismo , Neurônios/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Ligação ao Cálcio , Sequência Conservada , Células HEK293 , Humanos , Ligantes , Camundongos
12.
Asian-Australas J Anim Sci ; 33(2): 349-359, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31010974

RESUMO

Orchastric changes in the mammary glands are vital, especially during the lactaction. The secretary epithelial cells together with the supporting myoepithelial and stromal cells function cordially to secrete milk.Increase in the number of luminal epithelial cells and a decrease in adipocytes are visible during lactation, whereas the reverse happens in the involution. However, an early involution occurs if the epithelial transdifferente towards adipocytes in lactation period. We aimed to inhibit the adipocyte transdifferentiation of luminal cells by restraining the PPARγ pathway. Linolenic acid (LA) and thiazolidinediones (TZDs) induced adipogenesis in mammary epithelial cells were conducted in monolayer, mixed culture as well as in transwell plate co-culture with mammary myoepithelial cells.Co-culture with myoepithelial cells showed higher adipogenic gene expression in epithelial cells under LA+TZDs treatment. Increase in the expressions of PPARγ, C/EBPα and vimentin in both mRNA as well as protein levels were observed.Whereas,BADGE treatment blocked LA+TZDs induced adipogenesis, as it could not show a significant rise in adipose related markers. Although comparative results were found in both mixed culture and monolayer conditions, co-culture technic found to work better than the others. In summary, antagonizing PPARγ pathway in the presence of myoepithelial cells can significantly reduce the adipogenisis in epithelial cells, suggestingtherapeutic inhibition of PPARγ can be considered to counter early involution or excessive adipogenesis in mammary epithelium in animals.

13.
Nanotechnology ; 31(8): 085604, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31689698

RESUMO

Deoxyribonucleic acid (DNA) is effective for molecular computation because of its high energy efficiency, high information density, and parallel-computing capability. Although logic implementation using DNA molecules is well established in binary systems (base value of 2) via decoration of hairpin structures on DNA duplexes, systems with base values of >2 (e.g. 3, corresponding to a ternary system) are rarely discussed owing to the complexity of the design and the experimental difficulties with DNA. In this study, DNA rule tiles that participate to form algorithmic DNA crystals exhibiting the ternary representation of an N (N = 1 or 2)-input and 1-output algorithmic assembly are conceived. The number of possible algorithmic patterns is [Formula: see text] in the ternary N-input and 1-output logic gate. Thus, the number of possible rules is 27 (=33) for a 1-input and 1-output algorithmic logic gate and 19 638 (=39) for a 2-input and 1-output algorithmic logic gate. Ternary bit information (i.e. 0-, 1-, and 2-bit) is encoded on rule tiles without hairpins and with short and long hairpins. We construct converged, line-like, alternating, and commutative patterns by implementing specific rules (TR00, TR05, TR07, and TR15, respectively) for the 1-input and 1-output gate and an ascending line-like pattern (with the rule of TR3785) for the 2-input and 1-output gate. Specific patterns generated on ternary-representing rule-embedded algorithmic DNA crystals are visualized via atomic force microscopy, and the errors during the growth of the crystals are analyzed (average error rates obtained for all experimental data are <4%). Our method can easily be extended to a system having base values of >3.

14.
J Neurosci ; 37(5): 1062-1080, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27986928

RESUMO

Three neuronal pentraxins are expressed in brain, the membrane-bound "neuronal pentraxin receptor" (NPR) and the secreted proteins NP1 and NARP (i.e., NP2). Neuronal pentraxins bind to AMPARs at excitatory synapses and play important, well-documented roles in the activity-dependent regulation of neural circuits via this binding activity. However, it is unknown whether neuronal pentraxins perform roles in synapses beyond modulating postsynaptic AMPAR-dependent plasticity, and whether they may even act in inhibitory synapses. Here, we show that NPR expressed in non-neuronal cells potently induces formation of both excitatory and inhibitory postsynaptic specializations in cocultured hippocampal neurons. Knockdown of NPR in hippocampal neurons, conversely, dramatically decreased assembly and function of both excitatory and inhibitory postsynaptic specializations. Overexpression of NPR rescued the NPR knockdown phenotype but did not in itself change synapse numbers or properties. However, the NPR knockdown decreased the levels of NARP, whereas NPR overexpression produced a dramatic increase in the levels of NP1 and NARP, suggesting that NPR recruits and stabilizes NP1 and NARP on the presynaptic plasma membrane. Mechanistically, NPR acted in excitatory synapse assembly by binding to the N-terminal domain of AMPARs; antagonists of AMPA and GABA receptors selectively inhibited NPR-induced heterologous excitatory and inhibitory synapse assembly, respectively, but did not affect neurexin-1ß-induced synapse assembly as a control. Our data suggest that neuronal pentraxins act as signaling complexes that function as general trans-synaptic organizers of both excitatory and inhibitory synapses by a mechanism that depends, at least in part, on the activity of the neurotransmitter receptors at these synapses. SIGNIFICANCE STATEMENT: Neuronal pentraxins comprise three neuronal proteins, neuronal pentraxin receptor (NPR) which is a type-II transmembrane protein on the neuronal surface, and secreted neuronal pentraxin-1 and NARP. The general functions of neuronal pentraxins at synapses have not been explored, except for their basic AMPAR binding properties. Here, we examined the functional role of NPR at synapses because it is the only neuronal pentraxin that is anchored to the neuronal cell-surface membrane. We find that NPR is a potent inducer of both excitatory and inhibitory heterologous synapses, and that knockdown of NPR in cultured neurons decreases the density of both excitatory and inhibitory synapses. Our data suggest that NPR performs a general, previously unrecognized function as a universal organizer of synapses.


Assuntos
Proteína C-Reativa/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Sinapses/fisiologia , Animais , Proteína C-Reativa/antagonistas & inibidores , Proteína C-Reativa/genética , Proteína C-Reativa/metabolismo , Técnicas de Cocultura , Antagonistas de Aminoácidos Excitatórios/farmacologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Antagonistas GABAérgicos/farmacologia , Técnicas de Silenciamento de Genes , Células HEK293 , Hipocampo/fisiologia , Humanos , Camundongos , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios , Técnicas de Patch-Clamp , RNA Interferente Pequeno/genética , Receptores de AMPA/metabolismo , Receptores de Superfície Celular/metabolismo
15.
J Nanosci Nanotechnol ; 18(3): 2181-2184, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448741

RESUMO

Zinc oxide/activated carbon nanocomposites were synthesized by impregnating zinc oxide nanoparticles onto activated carbon powder using liquid phase plasma (LPP) method. Zinc oxide nanoparticles on the surface of activated carbon were fabricated rapidly by the LPP method due to reducing the zinc ion in aqueous solution. The obtained zinc oxide/activated carbon nanocomposites were characterized by XPS, HRTEM, and EDS. The amount of zinc oxide nanoparticles impregnated increased with increasing initial precursor concentration. Approximately 150~300 nm sized spherical shaped nanoparticles were uniformly dispersed on the surface of activated carbon powder.

16.
Retina ; 38(1): 137-147, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28099315

RESUMO

PURPOSE: To evaluate preoperative factors influencing the visual outcome and postoperative factors associated with the changes in visual acuity, after reattachment surgery to treat macula-off rhegmatogenous retinal detachment. METHODS: A total of 180 eyes of 180 patients who underwent reattachment surgery to treat macula-off rhegmatogenous retinal detachment, and who were followed up for more than 12 months, were reviewed retrospectively. Preoperative and postoperative characteristics, including optical coherence tomography findings, were comprehensively analyzed using univariate and multivariate models to evaluate preoperative factors influencing best-corrected visual acuity 12 months after macula-off rhegmatogenous retinal detachment surgery and postoperative factors associated with changes in best-corrected visual acuity after surgery. RESULTS: Preoperatively, the extent of detachment (P = 0.037), macula-off duration (P < 0.001), and integrity of the external limiting membrane (ß = 0.163; P = 0.002) were significantly associated with postoperative visual prognosis. Six factors were associated with changes in visual acuity after surgery: disruption of ellipsoid zone integrity (ß = 0.167; P < 0.001), the Henle's fiber layer and the outer nuclear layer (HFL + ONL)/photoreceptor layer ratio (ß = 0.199; P < 0.001), the photoreceptor outer segment length (ß = -0.020; P < 0.001), the photoreceptor inner segment length/photoreceptor outer segment length ratio (ß = 0.047; P = 0.005), the ratio of photoreceptor layer thickness between the RD eye and fellow eye (ß = -0.126; P = 0.018), and the photoreceptor outer segment length ratio between the RD eye and fellow eye (ß = -0.425; P < 0.001). CONCLUSION: Preoperative factors associated with the visual outcome after macula-off rhegmatogenous retinal detachment surgery were the extent of detachment, macula-off duration, and external limiting membrane integrity. Postoperatively, predictive factors were the outer retinal microstructures, particularly the photoreceptor outer segment layer.


Assuntos
Macula Lutea/cirurgia , Procedimentos Cirúrgicos Oftalmológicos/métodos , Descolamento Retiniano/cirurgia , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Macula Lutea/patologia , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Prognóstico , Descolamento Retiniano/diagnóstico , Estudos Retrospectivos , Adulto Jovem
17.
Int J Mol Sci ; 19(8)2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30082605

RESUMO

As an innovative technology in biological applications-non-thermal plasma technique-has recently been applied to living cells and tissues. However, it is unclear whether non-thermal plasma treatment can directly regulate the growth and development of livestock. In this study, we exposed four-day-incubated fertilized eggs to plasma at 11.7 kV for 2 min, which was found to be the optimal condition in respect of highest growth rate in chickens. Interestingly, plasma-treated male chickens conspicuously grew faster than females. Plasma treatment regulated the reactive oxygen species homeostasis by controlling the mitochondrial respiratory complex activity and up-regulating the antioxidant defense system. At the same time, growth metabolism was improved due to the increase of growth hormone and insulin-like growth factor 1 and their receptors expression, and the rise of thyroid hormones and adenosine triphosphate levels through the regulation of demethylation levels of growth and hormone biosynthesis-related genes in the skeletal muscles and thyroid glands. To our knowledge, this study was the first to evaluate the effects of a non-thermal plasma treatment on the growth rate of chickens. This safe strategy might be beneficial to the livestock industry.


Assuntos
Hormônios Tireóideos/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Galinhas , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Espécies Reativas de Oxigênio/metabolismo
18.
Molecules ; 23(8)2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-30127285

RESUMO

Diacylglycerol acyltransferases (DGATs) play a critical role in the biosynthesis of endogenous triglycerides (TGs) and formation of lipid droplets (LDs) in the liver. In particular, one member of DGATs, DGAT-1 was reported to be an essential host factor for the efficient production of hepatitis C virus (HCV) particles. By utilizing our previously characterized three different groups of twelve DGAT inhibitors, we found that one of the DGAT inhibitors, a 2-((4-adamantylphenoxy) methyl)-N-(furan-2-ylmethyl)-1H-benzo[d]imidazole-5-carboxam (10j) is a potent suppressor of both HCV genome replication and particle production. 10j was able to induce inhibition of these two critical viral functions in a mutually separate manner. Abrogation of the viral genome replication by 10j led to a significant reduction in the viral protein expression as well. Interestingly, we found that its antiviral effect did not depend on the reduction of TG biosynthesis by 10j. This suggests that the inhibitory activity of 10j against DGATs may not be directly related with its antiviral action.


Assuntos
Adamantano/análogos & derivados , Adamantano/farmacologia , Antivirais/farmacologia , Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Genoma Viral , Hepacivirus/efeitos dos fármacos , Imidazóis/farmacologia , Adamantano/química , Antivirais/química , Linhagem Celular , Sobrevivência Celular , Expressão Gênica , Hepacivirus/genética , Hepacivirus/fisiologia , Humanos , Imidazóis/química , RNA , Bibliotecas de Moléculas Pequenas , Vírion/efeitos dos fármacos , Vírion/fisiologia
19.
Int Ophthalmol ; 38(3): 1333-1337, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28523526

RESUMO

PURPOSE: To report a case of iris-fixated phakic intraocular lens (pIOL) implantation in a patient with an extremely steep cornea, shallow anterior chamber, and small corneal diameter caused by retinopathy of prematurity (ROP) and scleral encircling. METHODS: Case report. RESULTS: Iris-fixated pIOLs were implanted in a 19-year-old patient with refraction of -18.5 -0.75 × 180 in the right eye and -15.5 -1.25 × 180 in the left eye. The keratometric values were 53.50 and 51.25 diopters (D) in the right eye and 54.75 and 51.75 D in the left eye. The white-to-white diameter and anterior chamber depth were 10.6 and 3.37 mm, respectively, in the right eye and 10.5 and 3.33 mm, respectively, in the left eye. CONCLUSION: A small pIOL was used to guarantee a safety distance and resulted in a one-line gain in uncorrected distant visual acuity and stable endothelial cell density 1 year after surgery. An iris-fixated pIOL Vis therefore an effective option for myopic patients with ROP.


Assuntos
Cirurgia da Córnea a Laser/métodos , Iris/cirurgia , Miopia/cirurgia , Lentes Intraoculares Fácicas , Retinopatia da Prematuridade/complicações , Acuidade Visual , Córnea/patologia , Córnea/cirurgia , Topografia da Córnea , Feminino , Seguimentos , Humanos , Miopia/complicações , Miopia/fisiopatologia , Retinopatia da Prematuridade/diagnóstico , Fatores de Tempo , Adulto Jovem
20.
J Nanosci Nanotechnol ; 17(4): 2578-581, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29658690

RESUMO

Tin oxide/carbon nanocomposite (TOCNC) was synthesized using a liquid phase plasma method, to be used as the electrode of supercapacitor. Spherical tin oxide amorphous nanoparticles with the size of 5 nm were dispersed uniformly on activated carbon powder (ACP) surface. The quantity of tin oxide nanoparticle precipitate increased with increasing LPP duration and the specific capacitance of TOCNC increased with increasing LPP duration. The TOCNC prepared through the LPP process showed smaller resistances and larger initial resistance slopes than bare ACP and this effect was intensified by increasing the LPP process duration.

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