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2.
J Phys Chem Lett ; 12(46): 11361-11370, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34784226

RESUMO

Development of efficient bifunctional nonprecious metallic electrocatalysts for hydrogen electrochemistry in alkaline solution is of importance to enable commercialization of a low-cost alkaline hydrogen fuel cell and water electrolyzer, but it is very challenging. Two-dimensional (2D) MXene-based electrocatalysts hold tremendous potential for the applications of hydrogen fuel cell and water electrolyzer. Here, we successfully immobilized transition-metal-based NiMo nanoparticles (NPs) on 2D Ti3C2Tx (Tx: surface terminations, such as O, OH, or F) surfaces by a wet chemical method. Our results demonstrate that the NiMo NPs are monodispersed on Ti3C2Tx with surface functionalization. These monodisperse NPs resulted in superior hydrogen evolution reaction (HER) and hydrogen oxidation reaction (HOR) activities in an alkaline media. The NiMo NPs/Ti3C2Tx in 1.0 M KOH yielded an HER current of -10 mA cm-2 at -0.044 V vs reversible hydrogen electrode (RHE), nearly 232 mV smaller than that of the parent NiMo NPs. The NiMo NPs/Ti3C2Tx produced an HOR current density of 1.5 mA cm-2 at 0.1 V vs RHE. Density functional theory (DFT) results further reveal that Ti3C2Tx support can facilitate the charge transfer to metallic NPs and tailor the electronic structure of catalytic sites, resulting in optimized adsorption free energies of H* species for hydrogen electrochemistry. This work provides a facile and universal strategy in the development of 2D Ti3C2Tx with nonprecious metals for low-cost bifunctional hydrogen electrocatalysts.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34744070

RESUMO

BACKGROUND: The anterior cruciate ligament (ACL) reconstruction (ACLR) under the arthroscopy is a widespread procedure for ACL rupture, which could stabilize knee and promote recovery. However, one of its complications is the injury of infrapatellar branch of saphenous nerve (IBSN). In traditional Chinese medicine, acupotomy functions via releasing and stripping adhesion tissues. Accordingly, acupotomy is suitable for the treatment of entrapped nerve injury and tissues adhesion. CASE DESCRIPTION: A 14-year-old man, who had ACLR before and returned to normal activity, presented with severe pain after a mild strain two weeks ago. The physical and imaging examinations revealed the compression injury of IBSN. METHODS: We provided the ultrasound-guided perineural injection of 0.4% lidocaine, while it only alleviates the symptoms temporally and partially. Acupotomy using a small needle knife (0.4*40 mm) was performed. RESULTS: The severe pain was immediately resolved. The visual analog pain scale (VAS) decreased from 10 to 1 and return to normal walking. The diameter of IBSN became smaller and the signal of peripheral soft tissue became hypoechoic in ultrasound. CONCLUSION: In this case, the combined treatments of ultrasound-guided perineural injection and acupotomy are thought to be innovative procedures for IBSN entrapment with relative long-lasting therapeutic effects.

4.
Cell Discov ; 7(1): 103, 2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34719679

RESUMO

Epidemiological studies have demonstrated that the genetic factors partly influence the development of same-sex sexual behavior, but most genetic studies have focused on people of primarily European ancestry, potentially missing important biological insights. Here, we performed a two-stage genome-wide association study (GWAS) with a total sample of 1478 homosexual males and 3313 heterosexual males in Han Chinese populations and identified two genetic loci (rs17320865, Xq27.3, FMR1NB, Pmeta = 8.36 × 10-8, OR = 1.29; rs7259428, 19q12, ZNF536, Pmeta = 7.58 × 10-8, OR = 0.75) showing consistent association with male sexual orientation. A fixed-effect meta-analysis including individuals of Han Chinese (n = 4791) and European ancestries (n = 408,995) revealed 3 genome-wide significant loci of same-sex sexual behavior (rs9677294, 2p22.1, SLC8A1, Pmeta = 1.95 × 10-8; rs2414487, 15q21.3, LOC145783, Pmeta = 4.53 × 10-9; rs2106525, 7q31.1, MDFIC, Pmeta = 6.24 × 10-9). These findings may provide new insights into the genetic basis of male sexual orientation from a wider population scope. Furthermore, we defined the average ZNF536-immunoreactivity (ZNF536-ir) concentration in the suprachiasmatic nucleus (SCN) as lower in homosexual individuals than in heterosexual individuals (0.011 ± 0.001 vs 0.021 ± 0.004, P = 0.013) in a postmortem study. In addition, compared with heterosexuals, the percentage of ZNF536 stained area in the SCN was also smaller in the homosexuals (0.075 ± 0.040 vs 0.137 ± 0.103, P = 0.043). More homosexual preference was observed in FMR1NB-knockout mice and we also found significant differences in the expression of serotonin, dopamine, and inflammation pathways that were reported to be related to sexual orientation when comparing CRISPR-mediated FMR1NB knockout mice to matched wild-type target C57 male mice.

5.
Proc Natl Acad Sci U S A ; 118(34)2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34417312

RESUMO

Interactions of electronic and vibrational degrees of freedom are essential for understanding excited-states relaxation pathways of molecular systems at interfaces and surfaces. Here, we present the development of interface-specific two-dimensional electronic-vibrational sum frequency generation (2D-EVSFG) spectroscopy for electronic-vibrational couplings for excited states at interfaces and surfaces. We demonstrate this 2D-EVSFG technique by investigating photoexcited interface-active (E)-4-((4-(dihexylamino) phenyl)diazinyl)-1-methylpyridin-1- lum (AP3) molecules at the air-water interface as an example. Our 2D-EVSFG experiments show strong vibronic couplings of interfacial AP3 molecules upon photoexcitation and subsequent relaxation of a locally excited (LE) state. Time-dependent 2D-EVSFG experiments indicate that the relaxation of the LE state, S 2, is strongly coupled with two high-frequency modes of 1,529.1 and 1,568.1 cm-1 Quantum chemistry calculations further verify that the strong vibronic couplings of the two vibrations promote the transition from the S 2 state to the lower excited state S 1 We believe that this development of 2D-EVSFG opens up an avenue of understanding excited-state dynamics related to interfaces and surfaces.

6.
ACS Synth Biol ; 10(9): 2331-2339, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34449215

RESUMO

Bacillus licheniformis DW2 is an important industrial strain for bacitracin production, and it is also used for biochemical production, however, the lack of effective toolkit for precise regulation of gene expression hindered its application seriously. Here, a gradient strength promoter library was constructed based on bacitracin synthetase gene cluster promoter PbacA. First, different PbacA promoter variants were constructed via coupling PbacA with various 5'-UTRs, and expression ranges of 32.6-741.8% were attained among these promoters. Then, three promoters, PUbay (strong), PbacA (middle), and PUndh (weakest), were applied for red fluorescent protein (RFP) and keratinase expression assays, and these promoters were proven to have good universality for different proteins. Second, the promoter of bacitracin synthetase gene cluster was replaced by these three promoters, and bacitraicn titer was enhanced by 14.62% when PUbay was applied, which was decreased by 98.05% under the mediation of PUndh compared with that of the original strain DW2. Third, promoters PUbay, PUyvgO, and PUndh were selected to regulate the expression levels of critical genes that are responsible for pucheriminic acid synthesis, and pucheriminic acid yield was increased by 194.1% via manipulating synthetic and competitive pathways. Finally, promoters PUbay, PbacA, and PUndh were applied for green fluorescent protein (GFP) and RFP expression in Escherichia coli, and consistent effects were attained based on our results. Taken together, a gradient strength promoter library was constructed in this research, which provided an effective toolkit for fine-tuning gene expression and reprogramming metabolite metabolic flux in B. licheniformis.

7.
Elife ; 102021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34269178

RESUMO

Vesicular neurotransmitter transporters (VNTs) mediate the selective uptake and enrichment of small-molecule neurotransmitters into synaptic vesicles (SVs) and are therefore a major determinant of the synaptic output of specific neurons. To identify novel VNTs expressed on SVs (thus identifying new neurotransmitters and/or neuromodulators), we conducted localization profiling of 361 solute carrier (SLC) transporters tagging with a fluorescent protein in neurons, which revealed 40 possible candidates through comparison with a known SV marker. We parallelly performed proteomics analysis of immunoisolated SVs and identified seven transporters in overlap. Ultrastructural analysis further supported that one of the transporters, SLC35D3, localized to SVs. Finally, by combining metabolite profiling with a radiolabeled substrate transport assay, we identified UDP-glucose as the principal substrate for SLC35D3. These results provide new insights into the functional role of SLC transporters in neurotransmission and improve our understanding of the molecular diversity of chemical transmitters.


Assuntos
Transporte Biológico/fisiologia , Neurônios/metabolismo , Proteômica , Vesículas Sinápticas/metabolismo , Uridina Difosfato Glucose/metabolismo , Animais , Glucose/metabolismo , Células HEK293 , Humanos , Camundongos , Proteínas de Transporte de Monossacarídeos/metabolismo , Neurotransmissores/metabolismo , Ratos , Ratos Sprague-Dawley , Transmissão Sináptica/fisiologia
8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(4): 598-604, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34323037

RESUMO

Objective: To investigate the in vitro eradicative effect of self-assembled azithromycin/rhamnolipid nanoparticles (AZI-RHL NPs) on P seudomonas aeruginosa ( P. aeruginosa) biofilm. Methods: AZI-RHL NPs were prepared and characterized. The minimum inhibitory concentration (MIC) of AZI-RHL NPs on planktonic P. aeruginosa was measured by the broth microdilution method. The eradicative effect of AZI-RHL NPs on P. aeruginosa biofilm was evaluated via crystal violet staining and SYTO 9/PI live/dead staining. Fluorescence labeling was used to measure the eradicative effect of NPs on extracellular polymeric substances (EPS). In addition, crystal violet staining was performed to evaluate the inhibitory effect of AZI-RHL NPs on the adhesion of P. aeruginosa on human bronchial epithelial BEAS-2B cells. To investigate the ability of AZI-RHL NPs to penetrate mucus, the interaction between NPs and mucin was measured via particle size changes after co-incubation with mucin solution. Results: The AZI-RHL NPs had a particle size of about 121 nm and were negatively charged on the surface, displaying a high encapsulation efficiency and a high drug loading capacity of 96.72% and 45.08% for AZI, respectively and 99.38% and 53.07% for RHL, respectively. The MIC of AZI-RHL NPs on planktonic P. aeruginosa was half of that of using AZI alone. AZI-RHL NPs displayed the capacity to effectively destroy the biofilm structure and remove the proteins and polysaccharides in EPS, eradicating biofilms in addition to reducing the survival rate of bacteria in the biofilm. AZI-RHL NPs were shown to have inhibited P. aeruginosa adhesion on BEAS-2B cells and prevented the residual bacteria from forming a new biofilm. There was no significant change in the particle size of NPs after co-incubation with mucin solution, indicating a weak interaction between NPs and mucin, and suggesting that NPs could penetrate the mucus and reach the P. aeruginosa infection sites. Conclusion: AZI-RHL NPs were able to effectively enhance the removal of P. aeruginosa biofilm through a four-step strategy of biofilm eradication, including penetrating the mucus, disintegrating the biofilm structure, killing the bacteria dispersed from biofilm, and preventing the adhesion of residual bacteria. We hope that this study will provide a replicable common strategy for the treatment of refractory infections caused by P. aeruginosa and other types of biofilms.


Assuntos
Nanopartículas , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Azitromicina/farmacologia , Biofilmes , Glicolipídeos , Humanos , Testes de Sensibilidade Microbiana
9.
Angew Chem Int Ed Engl ; 60(32): 17356-17361, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34081389

RESUMO

Molecular doping is an of significance approach to reduce defects density of perovskite and to improve interfacial charge extraction in perovskite solar cells. Here, we show a new strategy for chemical doping of perovskite via an organic small molecule, which features a fused tricyclic core, showing strong intermolecular π-Pb2+ interactions with under-coordinated Pb2+ in perovskite. This π-Pb2+ interactions could reduce defects density of the perovskite and suppress the nonradiative recombination, which was also confirmed by the density functional theory calculations. In addition, this doping via π-Pb2+ interactions could deepen the surface potential and downshift the work function of the doped perovskite film, facilitating the hole extraction to hole transport layer. As a result, the doped device showed high efficiency of 21.41 % with ignorable hysteresis. This strategy of fused tricyclic core-based doping provides a new perspective for the design of new organic materials to improve the device performance.

10.
J Biol Chem ; 297(1): 100775, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34022218

RESUMO

Cellular pyruvate is an essential metabolite at the crossroads of glycolysis and oxidative phosphorylation, capable of supporting fermentative glycolysis by reduction to lactate mediated by lactate dehydrogenase (LDH) among other functions. Several inherited diseases of mitochondrial metabolism impact extracellular (plasma) pyruvate concentrations, and [1-13C]pyruvate infusion is used in isotope-labeled metabolic tracing studies, including hyperpolarized magnetic resonance spectroscopic imaging. However, how these extracellular pyruvate sources impact intracellular metabolism is not clear. Herein, we examined the effects of excess exogenous pyruvate on intracellular LDH activity, extracellular acidification rates (ECARs) as a measure of lactate production, and hyperpolarized [1-13C]pyruvate-to-[1-13C]lactate conversion rates across a panel of tumor and normal cells. Combined LDH activity and LDHB/LDHA expression analysis intimated various heterotetrameric isoforms comprising LDHA and LDHB in tumor cells, not only canonical LDHA. Millimolar concentrations of exogenous pyruvate induced substrate inhibition of LDH activity in both enzymatic assays ex vivo and in live cells, abrogated glycolytic ECAR, and inhibited hyperpolarized [1-13C]pyruvate-to-[1-13C]lactate conversion rates in cellulo. Of importance, the extent of exogenous pyruvate-induced inhibition of LDH and glycolytic ECAR in live cells was highly dependent on pyruvate influx, functionally mediated by monocarboxylate transporter-1 localized to the plasma membrane. These data provided evidence that highly concentrated bolus injections of pyruvate in vivo may transiently inhibit LDH activity in a tissue type- and monocarboxylate transporter-1-dependent manner. Maintaining plasma pyruvate at submillimolar concentrations could potentially minimize transient metabolic perturbations, improve pyruvate therapy, and enhance quantification of metabolic studies, including hyperpolarized [1-13C]pyruvate magnetic resonance spectroscopic imaging and stable isotope tracer experiments.


Assuntos
L-Lactato Desidrogenase/antagonistas & inibidores , Transportadores de Ácidos Monocarboxílicos/metabolismo , Ácido Pirúvico/farmacologia , Simportadores/metabolismo , Ácidos/metabolismo , Tampões (Química) , Isótopos de Carbono , Extratos Celulares , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Espaço Extracelular/química , Glicólise/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Cinética , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/biossíntese , Especificidade por Substrato/efeitos dos fármacos
11.
Medicine (Baltimore) ; 100(16): e25542, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33879701

RESUMO

ABSTRACT: The disease progression of gouty arthritis (GA) is relatively clear, with the 4 stages of hyperuricemia (HUA), acute gouty arthritis (AGA), gouty arthritis during the intermittent period (GIP), and chronic gouty arthritis (CGA). This paper attempts to construct a clinical diagnostic model based on blood routine test data, in order to avoid the need for bursa fluid examination and other tedious steps, and at the same time to predict the development direction of GA.Serum samples from 579 subjects were collected within 3 years in this study and were divided into a training set (n = 379) and validation set (n = 200). After a series of multivariate statistical analyses, the serum biochemical profile was obtained, which could effectively distinguish different stages of GA. A clinical diagnosis model based on the biochemical index of the training set was established to maximize the probability of the stage as a diagnosis, and the serum biochemical data from 200 patients were used for validation.The total area under the curve (AUC) of the clinical diagnostic model was 0.9534, and the AUCs of the 5 models were 0.9814 (Control), 0.9288 (HUA), 0.9752 (AGA), 0.9056 (GIP), and 0.9759 (CGA). The kappa coefficient of the clinical diagnostic model was 0.80.This clinical diagnostic model could be applied clinically and in research to improve the accuracy of the identification of the different stages of GA. Meanwhile, the serum biochemical profile revealed by this study could be used to assist the clinical diagnosis and prediction of GA.


Assuntos
Artrite Gotosa/diagnóstico , Regras de Decisão Clínica , Testes Hematológicos/estatística & dados numéricos , Adulto , Área Sob a Curva , Artrite Gotosa/etiologia , Biomarcadores/sangue , Sedimentação Sanguínea , Nitrogênio da Ureia Sanguínea , Proteína C-Reativa/análise , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Hiperuricemia/sangue , Hiperuricemia/complicações , Análise dos Mínimos Quadrados , Contagem de Leucócitos , Lipoproteínas HDL/sangue , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Valor Preditivo dos Testes , Análise de Componente Principal , Prognóstico , Análise de Regressão , Reprodutibilidade dos Testes , Ácido Úrico/sangue
12.
J Phys Chem A ; 125(17): 3589-3599, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33900754

RESUMO

Molecular symmetry is vital to the selection rule of vibrationally resolved electronic transition, particularly when the nuclear dependence of electronic wave function is explicitly treated by including Franck-Condon (FC) factor, Franck-Condon/Herzberg-Teller (FC/HT) interference, and Herzberg-Teller (HT) coupling. Our present study investigated the light absorption spectra of highly symmetric tetracene, pentacene, and hexacene molecules of point-group D2h, as well as their monobrominated derivatives with a lower Cs symmetry. It was found that the symmetry-breaking monobromination allows more vibrational normal modes and their pairs to contribute to FC/HT interference and HT coupling, respectively. Through a projection of a molecule's vibrational normal modes to its irreducible representations, a linear relationship between the FC/HT intensity to the polyacene's size was deduced alongside a quadratic dependence of the HT intensity. Both theoretically derived correlations were well justified by our numerical simulations, which also demonstrated an approximately 20% improvement on the agreement with experimental line shape if the HT theory is adopted to replace the FC approximation. Moreover, for these low-symmetry monobrominated polyacenes, the FC intensity was even weaker than its FC/HT and HT counterparts at some excitation energies, making the HT theory imperative to decipher vibronic coupling, a fundamental driving force behind numerous chemical, biological, and photophysical processes.

13.
ACS Appl Mater Interfaces ; 13(17): 20043-20050, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33896179

RESUMO

The efficiency loss and stability issues of perovskite devices mainly derive from nonradiative recombination, caused by detrimental defects in the perovskite bulk and at the interface between the perovskite absorber and charge transport layer. Therefore, the passivation of these defects is of great concern in achieving high-performance perovskite devices. Here, we report the incorporation of potassium phenyl trifluoroborate (KC6H5BF3) into perovskite films to realize simultaneous passivation of the grain boundaries and the perovskite/SnO2 interface. Apart from the bulk passivation of K+, the accumulation of C6H5BF3- at the buried interface contributes to the compact contact between the perovskite absorber and SnO2 layer and also the perfect columnar perovskite grains. As a result, the KC6H5BF3-containing perovskite films exhibit low trap density. The distinct enhancements of open-circuit voltage and photoelectric conversion efficiency are obtained together with negligible hysteresis. The open-circuit voltage of the KC6H5BF3-containing device increases from 1.09 to 1.18 V, and the corresponding efficiency increases from 19.69 to 22.33%. The finding in this work shows the superiority of the dual-functional additive for preparing highly efficient perovskite devices.

14.
Rev Sci Instrum ; 92(2): 023104, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648131

RESUMO

Structures, kinetics, and chemical reactivities at interfaces and surfaces are key to understanding many of the fundamental scientific problems related to chemical, material, biological, and physical systems. These steady-state and dynamical properties at interfaces and surfaces require even-order techniques with time-resolution and spectral-resolution. Here, we develop fourth-order interface-/surface-specific two-dimensional electronic spectroscopy, including both two-dimensional electronic sum frequency generation (2D-ESFG) spectroscopy and two-dimensional electronic second harmonic generation (2D-ESHG) spectroscopy, for structural and dynamics studies of interfaces and surfaces. The 2D-ESFG and 2D-ESHG techniques were based on a unique laser source of broadband short-wave IR from 1200 nm to 2200 nm from a home-built optical parametric amplifier. With the broadband short-wave IR source, surface spectra cover most of the visible light region from 480 nm to 760 nm. A translating wedge-based identical pulses encoding system (TWINs) was introduced to generate a phase-locked pulse pair for coherent excitation in the 2D-ESFG and 2D-ESHG. As an example, we demonstrated surface dark states and their interactions of the surface states at p-type GaAs (001) surfaces with the 2D-ESFG and 2D-ESHG techniques. These newly developed time-resolved and interface-/surface-specific 2D spectroscopies would bring new information for structure and dynamics at interfaces and surfaces in the fields of the environment, materials, catalysis, and biology.


Assuntos
Análise Espectral/instrumentação , Amplificadores Eletrônicos , Propriedades de Superfície , Vibração
15.
J Phys Chem Lett ; 12(12): 3142-3150, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33755478

RESUMO

Vibronic coupling is believed to play an important role in siglet fission, wherein a photoexcited singlet exciton is converted into two triplet excitons. In the present study, we examine the role of vibronic coupling in singlet fission using polarized transient absorption microscopy and ab initio simulations on single-crystalline pentacene. It was found that singlet fission in pentacene is greatly facilitated by the vibrational coherence of a 35.0 cm-1 phonon, where anisotropic coherence persists extensively for a few picoseconds. This coherence-preserving phonon that drives the anisotropic singlet fission is made possible by a unique cross-axial charge-transfer intermediate state. In the same fashion, this phonon was also found to predominantly drive the quantum decohence of a correlated triplet pair to form a decoupled triplet dimer. Moreover, our transient kinetic experimental data illustrates notable directional anisotropicity of the singlet fission rate in single-crystalline pentacene.

16.
Zhongguo Zhen Jiu ; 41(2): 217-20, 2021 Feb 12.
Artigo em Chinês | MEDLINE | ID: mdl-33788474

RESUMO

Given that the biomechanical theory cannot well explain the therapeutic effect of fan-ashi point (a special site that may relieve pain by pressing), the skeletal muscle tension is adopted and it is attempted to interpret the mechanism of the curative effect and the effect onset of fan-ashi point. It is viewed that the longitudinal tension conduction and transverse tension conduction pathways of skeletal muscle are the material basis of the effect onset of fan-ashi point. Hence, acupuncture at fan-ashi point may alter the longitudinal or transverse tension conduction of skeletal muscle to relieve muscle and tendon pain.


Assuntos
Terapia por Acupuntura , Acupuntura , Dor Musculoesquelética , Pontos de Acupuntura , Humanos , Músculo Esquelético
17.
Commun Biol ; 4(1): 364, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33742082

RESUMO

The fruit fly, Drosophila melanogaster, has been used as a model organism for the molecular and genetic dissection of sleeping behaviors. However, most previous studies were based on qualitative or semi-quantitative characterizations. Here we quantified sleep in flies. We set up an assay to continuously track the activity of flies using infrared camera, which monitored the movement of tens of flies simultaneously with high spatial and temporal resolution. We obtained accurate statistics regarding the rest and sleep patterns of single flies. Analysis of our data has revealed a general pattern of rest and sleep: the rest statistics obeyed a power law distribution and the sleep statistics obeyed an exponential distribution. Thus, a resting fly would start to move again with a probability that decreased with the time it has rested, whereas a sleeping fly would wake up with a probability independent of how long it had slept. Resting transits to sleeping at time scales of minutes. Our method allows quantitative investigations of resting and sleeping behaviors and our results provide insights for mechanisms of falling into and waking up from sleep.


Assuntos
Ciclos de Atividade , Comportamento Animal , Drosophila melanogaster/fisiologia , Fases do Sono , Fatores Etários , Animais , Locomoção , Modelos Teóricos , Descanso , Fatores de Tempo , Gravação em Vídeo
18.
Sleep ; 44(7)2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-33493349

RESUMO

Sleep and arousal are both important for animals. The neurotransmitter acetylcholine (ACh) has long been found to promote both sleep and arousal in mammals, an apparent paradox which has also been found to exist in flies, causing much confusion in understanding sleep and arousal. Here, we have systematically studied all 13 ACh receptors (AChRs) in Drosophila to understand mechanisms underlying ACh function in sleep and arousal. We found that exogenous stimuli-induced arousal was decreased in nAChRα3 mutants, whereas sleep was decreased in nAChRα2 and nAChRß2 mutants. nAChRα3 functions in dopaminergic neurons to promote exogenous stimuli-induced arousal, whereas nAChRα2 and ß2 function in octopaminergic neurons to promote sleep. Our studies have revealed that a single transmitter can promote endogenous sleep and exogenous stimuli-induced arousal through distinct receptors in different types of downstream neurons.


Assuntos
Nível de Alerta , Drosophila , Animais , Neurônios , Receptores Colinérgicos , Sono
19.
J Hum Genet ; 66(3): 261-271, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32939015

RESUMO

The Ebbinghaus illusion (EI) is an optical illusion of relative size perception that reflects the contextual integration ability in the visual modality. The current study investigated the genetic basis of two subtypes of EI, EI overestimation, and EI underestimation in humans, using quantitative genomic analyses. A total of 2825 Chinese adults were tested on their magnitudes of EI overestimation and underestimation using the method of adjustment, a standard psychophysical protocol. Heritability estimation based on common single nucleotide polymorphisms (SNPs) revealed a moderate heritability (34.3%) of EI overestimation but a nonsignificant heritability of EI underestimation. A meta-analysis of two phases (phase 1: n = 1986, phase 2: n = 839) of genome-wide association study (GWAS) discovered 1969 and 58 SNPs reaching genome-wide significance for EI overestimation and EI underestimation, respectively. Among these SNPs, 55 linkage-disequilibrium-independent SNPs were associated with EI overestimation in phase 1 with genome-wide significance and their associations could be confirmed in phase 2 cohort. Gene-based analyses found seven genes to be associated with EI overestimation at the genome-wide level, two from meta-analysis, and five from classical two-stage analysis. Overall, this study provided consistent evidence for a substantial genetic basis of the Ebbinghaus illusion.


Assuntos
Estudo de Associação Genômica Ampla , Ilusões Ópticas/fisiologia , Percepção de Tamanho/fisiologia , Adolescente , Adulto , /genética , Feminino , Genótipo , Humanos , Individualidade , Desequilíbrio de Ligação , Masculino , Polimorfismo de Nucleotídeo Único , Córtex Visual/anatomia & histologia , Adulto Jovem
20.
Med Phys ; 48(3): 1182-1196, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33341975

RESUMO

PURPOSE: Volumetric medical image registration has important clinical significance. Traditional registration methods may be time-consuming when processing large volumetric data due to their iterative optimizations. In contrast, existing deep learning-based networks can obtain the registration quickly. However, most of them require independent rigid alignment before deformable registration; these two steps are often performed separately and cannot be end-to-end. METHODS: We propose an end-to-end joint affine and deformable network for three-dimensional (3D) medical image registration. The proposed network combines two deformation methods; the first one is for obtaining affine alignment and the second one is a deformable subnetwork for achieving the nonrigid registration. The parameters of the two subnetworks are shared. The global and local similarity measures are used as loss functions for the two subnetworks, respectively. Moreover, an anatomical similarity loss is devised to weakly supervise the training of the whole registration network. Finally, the trained network can perform deformable registration in one forward pass. RESULTS: The efficacy of our network was extensively evaluated on three public brain MRI datasets including Mindboggle101, LPBA40, and IXI. Experimental results demonstrate our network consistently outperformed several state-of-the-art methods with respect to the metrics of Dice index (DSC), Hausdorff distance (HD), and average symmetric surface distance (ASSD). CONCLUSIONS: The proposed network provides accurate and robust volumetric registration without any pre-alignment requirement, which facilitates the end-to-end deformable registration.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Algoritmos , Encéfalo/diagnóstico por imagem , Imageamento Tridimensional , Neuroimagem
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