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1.
Sci Adv ; 6(17): eaaz6767, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32494646

RESUMO

Bioelectronic devices should optimally merge a soft, biocompatible tissue interface with capacity for local, advanced signal processing. Here, we introduce an organic mixed-conducting particulate composite material (MCP) that can form functional electronic components by varying particle size and density. We created MCP-based high-performance anisotropic films, independently addressable transistors, resistors, and diodes that are pattern free, scalable, and biocompatible. MCP enabled facile and effective electronic bonding between soft and rigid electronics, permitting recording of neurophysiological data at the resolution of individual neurons from freely moving rodents and from the surface of the human brain through a small opening in the skull. We also noninvasively acquired high-spatiotemporal resolution electrophysiological signals by directly interfacing MCP with human skin. MCP provides a single-material solution to facilitate development of bioelectronic devices that can safely acquire, transmit, and process complex biological signals.

2.
Transl Neurosci ; 10: 180-186, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31410301

RESUMO

Background: General anesthesia and increasing age are two main risk factors for postoperative cognitive dysfunction (POCD). Effective agents for the prevention or treatment of POCD are urgently needed. L-655,708, an inverse agonist of α5 subunit-containing γ-aminobutyric acid subtype A (α5GABAA) receptors, can prevent anesthesia-induced memory deficits in young animals. However, there is a lack of evidence of its efficacy in old animals. Methodology: Young (3- to 5-month-old) and old (18- to 20-month-old) mice were given an inhalation of 1.33% isoflurane for 1 hour and their associative memory was evaluated 24 hours after anesthesia using fear-conditioning tests (FCTs). To evaluate the effect of L-655,708, mice received intraperitoneal injections of L-655,708 (0.7 mg/kg) or vehicle 30 minutes before anesthesia. Results: Old mice exhibited impaired memory and lower hippocampal α5GABAA levels than young mice under physiological conditions. Pre-injections of L-655,708 significantly alleviated isoflurane-induced memory decline in young mice, but not in old mice. Conclusions: L-655,708 is not as effective for the prevention of POCD in old mice as it is in young mice. The use of inverse agonists of α5GABAA in preventing POCD in old patients should be carefully considered.

3.
Neural Regen Res ; 14(6): 1029-1036, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30762015

RESUMO

The α5 subunit-containing gamma-amino butyric acid type A receptors (α5 GABAARs) are a distinct subpopulation that are specifically distributed in the mammalian hippocampus and also mediate tonic inhibitory currents in hippocampal neurons. These tonic currents can be enhanced by low-dose isoflurane, which is associated with learning and memory impairment. Inverse agonists of α5 GABAARs, such as L-655,708, are able to reverse the short-term memory deficit caused by low-dose isoflurane in young animals. However, whether these negative allosteric modulators have the same effects on aged rats remains unclear. In the present study, we mainly investigated the effects of L-655,708 on low-dose (1.3%) isoflurane-induced learning and memory impairment in elderly rats. Young (3-month-old) and aged (24-month-old) Wistar rats were randomly assigned to receive L-655,708 0.5 hour before or 23.5 hours after 1.3% isoflurane anesthesia. The Morris Water Maze tests demonstrated that L-655,708 injected before or after anesthesia could reverse the memory deficit in young rats. But in aged rats, application of L-655,708 only before anesthesia showed similar effects. Reverse transcription-polymerase chain reaction showed that low-dose isoflurane decreased the mRNA expression of α5 GABAARs in aging hippocampal neurons but increased that in young animals. These findings indicate that L-655,708 prevented but could not reverse 1.3% isoflurane-induced spatial learning and memory impairment in aged Wistar rats. All experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Academy of Military Medical Science of China (approval No. NBCDSER-IACUC-2015128) in December 2015.

4.
J Eukaryot Microbiol ; 66(3): 435-441, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30191674

RESUMO

Enterocytozoon bieneusi causes microsporidiosis, a condition with complex epidemiology involving both direct and indirect transmission routes. To assess the potential role of synanthropic rodents and flies in the transmission of this pathogen, a total of 277 cattle fecal samples, 199 synanthropic rodents, and 50 batches of 20 flies were collected from a cattle farm. These samples were screened for the presence of E. bieneusi by PCR and sequencing of the internal transcribed spacer (ITS) region of the rRNA gene. The positive rates of cattle, synanthropic rodents, and flies were 11.9% (33/277), 4.0% (8/199) and 12.0% (6/50), respectively. Nineteen genotypes were identified, including 11 known genotypes (BEB6, I, COS-I, EbpC, D, J, CHS5, CHG1 to CHG3 and CHG14) and eight novel genotypes (named CHC9 to CHC16). The dominant genotype detected in the present study, BEB6, was found in all three categories of hosts. Moreover, human pathogenic genotypes D and EbpC were also observed in both synanthropic rodents and flies. These results demonstrate that synanthropic rodents and flies may act as biological disseminator or mechanical vector in the transmission of microsporidiosis to humans. Efforts should be made to minimize threats from these commensal animals to public health.


Assuntos
Doenças dos Bovinos/transmissão , Enterocytozoon/fisiologia , Genótipo , Camundongos , Microsporidiose/veterinária , Ratos , Doenças dos Roedores/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , China/epidemiologia , Enterocytozoon/genética , Feminino , Moscas Domésticas/microbiologia , Microsporidiose/parasitologia , Microsporidiose/transmissão , Filogenia , Prevalência , Doenças dos Roedores/transmissão , Sarcofagídeos/microbiologia
5.
ACS Nano ; 12(12): 12503-12511, 2018 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-30507142

RESUMO

The recent boom in flexible and wearable electronic devices has increased the demand for flexible energy storage devices. The flexible lithium-sulfur (Li-S) battery is considered to be a promising candidate due to its high energy density and low cost. Herein, a flexible Li-S battery was fabricated based on an all-in-one integrated configuration, where a multiwalled carbon nanotubes/sulfur (MWCNTs/S) cathode, MWCNTs/manganese dioxide (MnO2) interlayer, polypropylene (PP) separator, and Li anode were integrated together by combining blade coating with vacuum evaporation methods. Each component of the all-in-one structure can be seamlessly connected with the neighboring layers. Such an optimal interfacial connection can effectively enhance electron- and/or load-transfer capacity by avoiding the relative displacement or detachment between two neighboring components at bending strain. Therefore, the flexible all-in-one Li-S batteries display fast electrochemical kinetics and have stable electrochemical performance under different bending states.

6.
Adv Exp Med Biol ; 1099: 167-177, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30306524

RESUMO

Pain is a complex neural function involving cognition, sensory, emotion, and memory. Imaging studies have shown that multiple brain regions are actively engaged in the processing of pain. However, roles of each brain regions and their contribution to pain are still largely unknown. Recent studies with electrophysiology especially high-density electroencephalogram (EEG) or multichannel recordings techniques have provided more insights into the dynamics of pain signature. The accumulations of the evidence could facilitate our understanding of pain and provide potential methods for objective pain evaluation and treatment of chronic pain.


Assuntos
Encéfalo/fisiologia , Eletroencefalografia , Fenômenos Eletrofisiológicos , Dor/fisiopatologia , Mapeamento Encefálico , Humanos
7.
ACS Chem Neurosci ; 9(7): 1849-1857, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-29722955

RESUMO

The excessive accumulation of iron in deep gray structures is an important pathological characteristic in patients with Alzheimer's disease (AD). Quantitative susceptibility mapping (QSM) is more specific than other imaging-based iron measurement modalities and allows noninvasive assessment of tissue magnetic susceptibility, which has been shown to correlate well with brain iron levels. This study aimed to investigate the correlations between the magnetic susceptibility values of deep gray matter nuclei and the cognitive functions assessed by mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA) in patients with mild and moderate AD. Thirty subjects with mild and moderate AD and 30 age- and sex-matched healthy controls were scanned with a 3.0 T magnetic resonance imaging (MRI) scanner. The magnetic susceptibilities of the regions of interest (ROIs), including caudate nucleus (Cd), putamen (Pt), globus pallidus (Gp), thalamus (Th), red nucleus (Rn), substantia nigra (Sn), and dentate nucleus (Dn), were quantified by QSM. We found that the susceptibility values of the bilateral Cd and Pt were significantly higher in AD patients than the controls ( P < 0.05). In contrast, bilateral Rn had significantly lower susceptibility values in AD than the controls. Regardless of gender and age, the increase of magnetic susceptibility in the left Cd was significantly correlated with the decrease of MMSE scores and MoCA scores ( P < 0.05). Our study indicated that magnetic susceptibility value of left Cd could be potentially used as a biomarker of disease severity in mild and moderate AD.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/psicologia , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Cognição , Ferro/metabolismo , Idoso , Doença de Alzheimer/metabolismo , Estudos de Coortes , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Índice de Gravidade de Doença
8.
Front Mol Neurosci ; 11: 24, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29472842

RESUMO

Injuries to peripheral nerve fibers induce neuropathic pain. But the involvement of adjacent uninjured fibers to pain is not fully understood. The present study aims to investigate the possible contribution of Cav3.2 T-type calcium channels in uninjured afferent nerve fibers to neuropathic pain in rats with spared nerve injury (SNI). Aß-, Aδ- and C-fibers of the uninjured sural nerve were sensitized revealed by in vivo single-unit recording, which were accompanied by accumulation of Cav3.2 T-type calcium channel proteins shown by Western blotting. Application of mibefradil, a T-type calcium channel blocker, to sural nerve receptive fields increased mechanical thresholds of Aß-, Aδ- and C-fibers, confirming the functional involvement of accumulated channels in the sural nerve in SNI rats. Finally, perineural application of mibefradil or TTA-P2 to the uninjured sural nerve alleviated mechanical allodynia in SNI rats. These results suggest that axonal accumulation of Cav3.2 T-type calcium channels plays an important role in the uninjured sural nerve sensitization and contributes to neuropathic pain.

9.
Front Neural Circuits ; 11: 71, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29062273

RESUMO

Previous studies have shown that multiple brain regions are involved in pain perception and pain-related neural processes by forming a functionally connected pain network. It is still unclear how these pain-related brain areas actively work together to generate the experience of pain. To get a better insight into the pain network, we implanted electrodes in four pain-related areas of rats including the anterior cingulate cortex (ACC), orbitofrontal cortex (OFC), primary somatosensory cortex (S1) and periaqueductal gray (PAG). We analyzed the pattern of local field potential (LFP) oscillations under noxious laser stimulations and innoxious laser stimulations. A high-dimensional feature matrix was built based on the LFP characters for both experimental conditions. Generalized linear models (GLMs) were trained to classify recorded LFPs under noxious vs. innoxious condition. We found a general power decrease in α and ß bands and power increase in γ band in the recorded areas under noxious condition. After noxious laser stimulation, there was a consistent change in LFP power and correlation in all four brain areas among all 13 rats. With GLM classifiers, noxious laser trials were distinguished from innoxious laser trials with high accuracy (86%) using high-dimensional LFP features. This work provides a basis for further research to examine which aspects (e.g., sensory, motor or affective processes) of noxious stimulation should drive distinct neural activity across the pain network.


Assuntos
Giro do Cíngulo/fisiopatologia , Dor Nociceptiva/fisiopatologia , Substância Cinzenta Periaquedutal/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Córtex Somatossensorial/fisiopatologia , Animais , Ondas Encefálicas , Modelos Animais de Doenças , Eletrodos Implantados , Lasers , Masculino , Vias Neurais/fisiopatologia , Nociceptividade/fisiologia , Ratos Sprague-Dawley , Processamento de Sinais Assistido por Computador
10.
Neurosci Bull ; 33(6): 653-663, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28900900

RESUMO

The local field potential (LFP) is a signal reflecting the electrical activity of neurons surrounding the electrode tip. Synchronization between LFP signals provides important details about how neural networks are organized. Synchronization between two distant brain regions is hard to detect using linear synchronization algorithms like correlation and coherence. Synchronization likelihood (SL) is a non-linear synchronization-detecting algorithm widely used in studies of neural signals from two distant brain areas. One drawback of non-linear algorithms is the heavy computational burden. In the present study, we proposed a graphic processing unit (GPU)-accelerated implementation of an SL algorithm with optional 2-dimensional time-shifting. We tested the algorithm with both artificial data and raw LFP data. The results showed that this method revealed detailed information from original data with the synchronization values of two temporal axes, delay time and onset time, and thus can be used to reconstruct the temporal structure of a neural network. Our results suggest that this GPU-accelerated method can be extended to other algorithms for processing time-series signals (like EEG and fMRI) using similar recording techniques.


Assuntos
Algoritmos , Sincronização de Fases em Eletroencefalografia/fisiologia , Eletroencefalografia/métodos , Modelos Teóricos , Processamento de Sinais Assistido por Computador , Animais , Funções Verossimilhança , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
11.
Sci Adv ; 2(11): e1601027, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28861464

RESUMO

Localizing neuronal patterns that generate pathological brain signals may assist with tissue resection and intervention strategies in patients with neurological diseases. Precise localization requires high spatiotemporal recording from populations of neurons while minimizing invasiveness and adverse events. We describe a large-scale, high-density, organic material-based, conformable neural interface device ("NeuroGrid") capable of simultaneously recording local field potentials (LFPs) and action potentials from the cortical surface. We demonstrate the feasibility and safety of intraoperative recording with NeuroGrids in anesthetized and awake subjects. Highly localized and propagating physiological and pathological LFP patterns were recorded, and correlated neural firing provided evidence about their local generation. Application of NeuroGrids to brain disorders, such as epilepsy, may improve diagnostic precision and therapeutic outcomes while reducing complications associated with invasive electrodes conventionally used to acquire high-resolution and spiking data.


Assuntos
Encéfalo/fisiopatologia , Eletrocorticografia , Epilepsia/fisiopatologia , Adulto , Eletrocorticografia/instrumentação , Eletrocorticografia/métodos , Eletrônica Médica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Neural Regen Res ; 11(12): 1951-1955, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28197191

RESUMO

Isoflurane is a widely used inhaled anesthetic in the clinical setting. However, the mechanism underlying its effect on consciousness is under discussion. Therefore, we investigated the effect of isoflurane on the hippocampus and cortex using an in vivo field recording approach. Our results showed that 1.3%, 0.8%, and 0.4% isoflurane exerted an inhibitory influence on the mouse hippocampus and cortex. Further, high frequency bands in the cortex and hippocampus showed greater suppression with increasing isoflurane concentration. Our findings suggest that in vivo field recordings can monitor the effect of isoflurane anesthesia on the mouse cortex and hippocampus.

13.
Parasit Vectors ; 7: 190, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-24742088

RESUMO

BACKGROUND: Cryptosporidium and Giardia are important causes of diarrhea diseases in humans and animals worldwide, and both of them are transmitted by the fecal-oral route, either by direct contact or by the ingestion of contaminated food or water. The role of flies in the mechanical transmission of Cryptosporidium and Giardia has been receiving increasing attention. To date, no information is available in China about the occurrence of Cryptosporidium and Giardia in flies. We here investigated Cryptosporidium and Giardia in flies on dairy farms in Henan Province, China, at the genotype and subtype levels. METHODS: Eight hundred flies were randomly collected from two dairy farms from July 2010 to September 2010 and were divided evenly into 40 batches. The fly samples were screened for the presence of Cryptosporidium and Giardia with nested PCR. Cryptosporidium was genotyped and subtyped by analyzing the DNA sequences of small subunit rRNA (SSU rRNA) and 60-kDa glycoprotein (gp60) genes, respectively. The identity of Giardia was determined by sequence analyzing of the triosephosphate isomerase (tpi), glutamate dehydrogenase (gdh), and ß-giardin (bg) genes. RESULTS: Forty batches of flies had 10% of contamination with Cryptosporidium or Giardia, with a mixed infection of the two parasites in one batch of flies. The Cryptosporidium isolates were identified as C. parvum at the SSU rRNA locus, and all belonged to subtype IIdA19G1 at the gp60 locus. The Giardia isolates were all identified as assemblage E of G. duodenalis at the tpi, gdh, and bg loci. One novel subtype of assemblage E was identified based on the gdh and bg loci. CONCLUSIONS: This is the first molecular study of Cryptosporidium and Giardia in flies identified at both genotype and subtype levels. SSU rRNA and gp60 sequences of C. parvum in flies was 100% homologous with those derived from humans, suggesting flies act as an epidemiological vector of zoonotic cryptosporidiosis. The variable PCR efficiencies observed in the analysis of Giardia at different loci suggest that we should use the multilocus genotyping tool in future studies to increase the detection rate, and importantly, to obtain more complete genetic information on Giardia isolates.


Assuntos
Bovinos , Cryptosporidium parvum/isolamento & purificação , Indústria de Laticínios , Dípteros/parasitologia , Giardia lamblia/isolamento & purificação , Animais , China , Cryptosporidium parvum/genética , Genótipo , Giardia lamblia/genética , Reação em Cadeia da Polimerase/métodos
14.
Sci Rep ; 4: 4208, 2014 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-24572610

RESUMO

In this study, 111 Cryptosporidium parvum IId isolates from several species of animals in China, Sweden, and Egypt were subtyped by multilocus sequence typing (MLST). One to eleven subtypes were detected at each of the 12 microsatellite, minisatellite, and single nucleotide polymorphism (SNP) loci, forming 25 MLST subtypes. Host-adaptation and significant geographical segregation were both observed in the MLST subtypes. A clonal population structure was seen in C. parvum IId isolates from China and Sweden. Three ancestral lineages and the same RPGR sequence were shared by these isolates examined. Therefore, the present genetic observations including the higher nucleotide diversity of C. parvum IId GP60 sequences in Western Asia, as well as the unique distribution of IId subtypes (almost exclusively found in Asia, Europe, and Egypt) and in combination with the domestication history of cattle, sheep, and goats, indicated that C. parvum IId subtypes were probably dispersed from Western Asia to other geographical regions. More population genetic structure studies involving various C. parvum subtype families using high-resolution tools are needed to better elucidate the origin and dissemination of C. parvum in the world.


Assuntos
Cryptosporidium parvum/classificação , Cryptosporidium parvum/genética , China , Cryptosporidium parvum/isolamento & purificação , Egito , Genes de Protozoários , Variação Genética , Genética Populacional , Desequilíbrio de Ligação , Repetições Minissatélites , Dados de Sequência Molecular , Tipagem de Sequências Multilocus , Filogenia , Filogeografia , Polimorfismo de Nucleotídeo Único , Suécia
15.
Brain Res ; 1427: 65-77, 2012 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-22050959

RESUMO

The role of satellite glial cells (SGCs) of sensory ganglia in chronic pain begins to receive interest. The present study aims to investigate the contribution of SGC activation to the development of neuropathic pain. A neuropathic pain model was established by lumbar 5 spinal nerve ligation (SNL), and glial fibrillary acidic protein (GFAP) was used as a marker of SGC activation. It was found that SGCs were activated in the ipsilateral dorsal root ganglia (DRG) increased significantly as early as 4h following SNL, gradually increased to a peak level at day 7, and then stayed at a high level to the end of the experiment at day 56. SGC activation in the SNL group was significantly higher than that in the sham group at days 1, 3 and 7 after operation. Immunofluorescent double labeling showed that the activated SGCs encircled large, medium-sized and small neurons. The SGCs surrounded the small and medium-sized neurons were preferentially activated in the early phase, but shifted to large diameter neurons as time went on. Continuous infusion of fluorocitrate, a glial metabolism inhibitor, to the affected DRG via mini-osmotic pump for 7d significantly alleviated mechanical allodynia at day 7. These results suggest that SGCs in the DRG were activated after SNL. SGC activation contributed to the early maintenance of neuropathic pain.


Assuntos
Gânglios Espinais/patologia , Gliose/patologia , Doenças do Sistema Nervoso Periférico/patologia , Células Satélites Perineuronais/patologia , Animais , Dor Crônica , Modelos Animais de Doenças , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/fisiopatologia , Gliose/tratamento farmacológico , Gliose/fisiopatologia , Masculino , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/fisiopatologia , Ratos , Ratos Sprague-Dawley , Células Satélites Perineuronais/efeitos dos fármacos , Células Satélites Perineuronais/fisiologia , Neuropatia Ciática/tratamento farmacológico , Neuropatia Ciática/patologia , Neuropatia Ciática/fisiopatologia
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