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The goal of this study was to investigate the origin of brain lactate (Lac) signal in the healthy anesthetized rat after injection of hyperpolarized (HP) [1-13 C]pyruvate (Pyr). Dynamic two-dimensional spiral chemical shift imaging with flow-sensitizing gradients revealed reduction in both vascular and brain Pyr, while no significant dependence on the level of flow suppression was detected for Lac. These results support the hypothesis that the HP metabolites predominantly reside in different compartments in the brain (i.e., Pyr in the blood and Lac in the parenchyma). Data from high-resolution metabolic imaging of [1-13 C]Pyr further demonstrated that Lac detected in the brain was not from contributions of vascular signal attributable to partial volume effects. Additionally, metabolite distributions and kinetics measured with dynamic imaging after injection of HP [1-13 C]Lac were similar to Pyr data when Pyr was used as the substrate. These data do not support the hypothesis that Lac observed in the brain after Pyr injection was generated in other organs and then transported across the blood-brain barrier (BBB). Together, the presented results provide further evidence that even in healthy anesthetized rats, the transport of HP Pyr across the BBB is sufficiently fast to permit detection of its metabolic conversion to Lac within the brain.
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Ácido Láctico , Ácido Pirúvico , Ratos , Animais , Ácido Pirúvico/metabolismo , Ácido Láctico/metabolismo , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Barreira Hematoencefálica/diagnóstico por imagem , Isótopos de Carbono/metabolismoRESUMO
The sluggish kinetics of anodic oxygen evolution reaction (OER) is regarded as the main bottleneck for ineffective hydrogen production efficiency, limiting the industrial application of electrochemical water splitting. Substituting the OER by urea electrooxidation reaction (UOR) and simultaneously developing highly active and economical bifunctional electrocatalyst for UOR and hydrogen evolution reaction (HER) is a promising method to realize energy-saving hydrogen production and urea-rich wastewater abatement. Herein, self-supporting Ni-NiO film grown on Ti mesh (Ni-NiO/TM) was successfully prepared by a facile cathodic electrodeposition method with using nickel acetate as the only raw material. Electrodeposition process was optimized by modulating the electrodeposition time and potential. x-ray diffraction, scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy and Raman characterization revealed the optimized Ni-NiO/TM was comprised of crystalline Ni and amorphous NiO and its morphology exhibited nanosphere structure, assembled by nanosheets. Ni-NiO/TM sample prepared under the potential of -1.5 V and deposition time of 10 min illustrated the lowest UOR potential of 1.34 V at 50 mA cm-2and robust stability, superior to the recently reported literatures. Furthermore, the HER potential was only -0.235 V to drive the current density of 50 mA cm-2. The cell voltage of urea-assisted electrolysis for hydrogen production in Ni-NiO/TM||Ni-NiO/TM two-electrode system only required 1.56 V to deliver 50 mA cm-2, obviously lower than that (>1.72 V) for overall water splitting. This work demonstrated the potential of Ni-based material as bifunctional electrocatalyst for energy-saving H2production by urea-rich wastewater electrolysis.
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Pneumonia is a condition characterized by lung damage resulting from a robust immune response by the host. While the defense and immunity against bacterial lung infections have been extensively studied, little is known about the specific immune factors involved in the progression of bacterial pneumonia. To address this knowledge gap, our study aimed to compare normal lung tissues with pneumonia tissues using various techniques, including HE staining, RNA sequencing, RT-PCR, and Elisa assay. Our analysis revealed a significant increase in the levels of interleukin-6 (IL-6) in pneumonia tissues compared to normal lung tissues. To further investigate the underlying mechanism, we extracted exosomes from both pneumonia and normal lung tissues using ultracentrifugation. The exosomes were then examined using electron microscopy, diameter analysis, and western blot assay. RNA sequencing of the exosomes revealed an upregulation of several microRNAs (miRNAs), with miR-362 exhibiting the most significant change. This finding was confirmed through RT-PCR analysis conducted on lung tissues and alveolar lavage fluid. To gain insights into the specific target genes of miR-362, we employed bioinformatics analysis, which identified VENTX as a potential target gene. This finding was further validated through RT-PCR, western blot, and luciferase assay. Our experimental evidence demonstrated that miR-362 regulates VENTX expression, as evidenced by the use of miR-362 mimics or inhibitors on lung cells. Furthermore, we discovered that exosomes derived from pneumonia tissues upregulate IL-6 production through the miR-362/VENTX axis. Importantly, the blocking of IL-6 generation, which is facilitated by miR-362 inhibitor and VENTX overexpression lentivirus, can be achieved by treating exosomes. Moreover, we conducted in vivo experiments using pneumonia models. Rats were treated with IL-6, miR-362 mimics, or VENTX knock-down lentivirus. The results demonstrated a worse prognosis for rats treated with these factors, indicating their potential as prognostic markers. Taken together, our study suggests that exosomes facilitate IL-6 generation by transferring miR-362, thereby suppressing VENTX transcription. Consequently, the IL-6/miR-362/VENTX axis emerges as a promising therapeutic target for pneumonia.
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Exossomos , MicroRNAs , Pneumonia , Ratos , Animais , Interleucina-6/genética , Interleucina-6/metabolismo , Exossomos/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Pneumonia/genética , Pneumonia/metabolismo , Pulmão/metabolismoRESUMO
Helicobacter pylori (H. pylori) is a well-known pathogen that infects approximately half of the world's population. It is a pathogenic agent with potential health hazards related to diverse diseases, especially digestive diseases, such as chronic gastritis, peptic ulcer, and gastric carcinoma. In clinical, antibiotics are commonly applied in eradication therapy of H. pylori. However, the increase in antibiotic resistance and side effects has induced the failure of eradication therapy. Recent studies have shown that probiotic supplementation has promising application prospects. It can restore the gastrointestinal microbiota balance and prevent dysbacteriosis caused by antibiotics. Furthermore, it has been reported to have direct or indirect inhibitory effects on H. pylori. Probiotics may have a beneficial effect on H. pylori eradication. However, the strain, dosages, duration times, and safety of probiotic supplementation need further study before clinical applications.
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Microbioma Gastrointestinal , Infecções por Helicobacter , Helicobacter pylori , Probióticos , Humanos , Infecções por Helicobacter/tratamento farmacológico , Probióticos/uso terapêutico , Antibacterianos/efeitos adversosRESUMO
To elucidate the antibacterial role of peroxinectin (referred to as PXN) and its molecular mechanism in Chinese mitten crab Eriocheir sinensis, we analyzed the bacterial binding and removal of the peroxinectin recombinant protein in vitro and the interaction of peroxinectin with integrin and CuZn-SOD through GST-pulldown and bimolecular fluorescence complementation methods. Concurrently, the effect of peroxinectin interference on the expression of other immune-related genes was studied using RNA interference. The results showed that the recombinant peroxinectin protein could bind to Bacillus subtilis, Staphylococcus aureus, Aeromonas hydrophila, and Vibrio parahaemolyticus with different affinities in vitro and could eliminate Vibrio parahaemolyticus in vivo. The findings also indicated that peroxinectin could establish interactions with integrin and CuZn-SOD in vitro. Furthermore, 48 h after the injection of the peroxinectin gene siRNA in vivo, the expression of peroxinectin mRNA decreased significantly (P < 0.05), integrin mRNA expression decreased by 16.8%, and CuZn-SOD mRNA expression decreased by 62.84% (P < 0.01). The expression levels of Dorsal, GPx, GST, PPAF, and Relish (P < 0.01), as well as that of lectin (P < 0.001) were significantly decreased. When peroxinectin siRNA was injected in vivo for 48 h and Aeromonas hydrophila was injected into mitten crabs, the expression of immune-related genes significantly increased. All data indicate that the recombinant peroxinectin protein in Chinese mitten crabs can recognize and bind different bacteria and promote the elimination of Vibrio parahaemolyticus from the body. Furthermore, peroxinectin may establish interactions with integrin and CuZn-SOD to activate the expression of related immune genes to elicit responses to bacterial infections and achieve immune protection.
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Braquiúros , Vibrio parahaemolyticus , Aeromonas hydrophila/fisiologia , Sequência de Aminoácidos , Animais , Antibacterianos/farmacologia , China , Hemócitos , Imunidade , Imunidade Inata/genética , Integrinas/metabolismo , Lipopolissacarídeos/farmacologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Superóxido Dismutase/metabolismoRESUMO
Flexible force sensors are of great interest in the fields of healthcare, physiological signals, and aircraft smart skin applications because of their compatibility with curved surfaces. However, the simultaneous detection of multidirectional forces remains an engineering challenge, despite the great progress made in recent years. Herein, we present the development of a flexible capacitive force sensor capable of efficiently distinguishing normal and sliding shear forces. A two-layer electrospun polyimide/graphene oxide (PI/GO) nanofiber membrane is used as the dielectric layer, which is sandwiched between one top electrode and four symmetrically distributed bottom electrodes. This composite membrane has an improved dielectric constant, a reduced friction coefficient, and good compressibility, leading to superior performance that includes high sensitivity over a wide operational range with measured results of 3 MPa-1for 0-242 kPa (0-2.2 N) and 0.92 MPa-1for 242-550 kPa (2.2-5 N) in the normal direction; and better than 1 N-1for 0-3 N in thex- andy-axis directions. The system also has a low detection limit of 10 Pa, fast response and recovery times of 39 ms and 13 ms, respectively, a good cyclic stability of 10,000 cycles at a pressure of 176 kPa, and promising potential for use in high-temperature environments (200 °C). Moreover, a prototype 4 × 4 sensor array has been fabricated and successfully used in a robotic system to grasp objects and operate a wireless toy car. As such, the proposed system could offer superior capabilities in simultaneous multidirectional force sensing for applications such as intelligent robots, human-machine interaction, and smart skin.
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Grafite , Nanofibras , Humanos , Fenômenos Mecânicos , TatoRESUMO
Centrifugal droplet-based microfluidic devices have been applied to biomedical analysis and diagnostics recently. However, in centrifugal droplet-based microfluidic devices, droplets are tightly packed (i.e., the oil film between neighbouring droplets is thin). Therefore, droplet coalescence usually occurs especially during thermal incubation process. To preserve individual droplets in the devices, we report a new design for monodisperse droplet generation and storage that exploits a centrifugal configuration for droplet emulsification and oil-storage structures (OSSs) for regulation of the thickness of oil film between neighbouring droplets. The centrifugal emulsifier was well designed to ensure uniform droplet generation. Meanwhile, the OSSs could store oil during centrifugal emulsification while release oil before thermal incubation, which "loosen" tightly packed droplets to prevent droplets from coalescing. In this paper, the working process of OSS was analysed, and its shape and size were optimized. Then, the optimized OSSs were integrated into a centrifugal emulsifier for droplet digital loop mediated isothermal amplification (ddLAMP) by which detection of JAK2 V617F mutation within myeloproliferative neoplasms with a dynamic range of 101 to 104 copies per µL was achieved. We anticipate that the simplicity and robustness of our system make it attractive as an inexpensive and easy-to-operate device for DNA amplification, particularly applicable in point-of-care settings.
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Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Óleos/química , Substituição de Aminoácidos , Centrifugação , Emulsões , Neoplasias Hematológicas/genética , Humanos , Janus Quinase 2/genética , Mutação de Sentido Incorreto , Transtornos Mieloproliferativos/genética , Proteínas de Neoplasias/genéticaRESUMO
PURPOSE: Developing a method for simultaneous metabolic imaging of copolarized [2-13 C]pyruvate and [1,4-13 C2 ]fumarate without chemical shift displacement artifacts that also permits different excitation flip angles for substrates and their metabolic products. METHODS: The proposed pulse sequence consists of 2 frequency-selective radiofrequency pulses to alternatingly excite 2 spectral sub-bands each one followed by a fast 3D spiral CSI (3D-spCSI) readout. Spectrally selective radiofrequency pulses were designed to excite differential flip angles on substrates and products in each spectral sub-band. Number of signal averages analysis was used to determine a spectral width suitable to resolve the metabolites of interest in each of the sub-bands. RESULTS: Phantom experiments verified the copolarization strategy and radiofrequency pulse design following differential flip angle used in our method. The signal behavior of the resonances in each sub-band was unaffected by the excitation of the respective alternate frequency band. Dynamic 3D 13 C CSI data demonstrated the ability of the sequence to image metabolites like pyruvate-hydrate, lactate, alanine, fumarate, and malate simultaneously and detect metabolic changes in the liver in a rat model of carbon tetrachloride-induced liver damage. CONCLUSION: The presented method allows the dynamic CSI of a mixture of [2-13 C]pyruvate and [1,4-13 C2 ]fumarate without chemical shift displacement artifacts while also permitting the use of different flip angles for substrate and product signals. The method is potentially useful for combined in vivo imaging of inflammation and cell necrosis.
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Fumaratos/química , Imageamento Tridimensional/métodos , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Ácido Pirúvico/química , Animais , Artefatos , Isótopos de Carbono/química , Masculino , Distribuição Normal , Imagens de Fantasmas , Ondas de Rádio , Ratos , Ratos Wistar , Processamento de Sinais Assistido por ComputadorRESUMO
Antibody-dependent cell-mediated cytotoxicity bridges humoral immunity and cellular immunity. Thus vaccine candidates which can elicit both broadly neutralizing antibodies and potent antibody-dependent cell-mediated cytotoxicity (ADCC) are recommended. Previously, a panel of functional epitopes that can elicit ADCC effects is isolated and characterized on the H1N1 Influenza Virus. Based on these identified epitopes, an epitope vaccine against H1N1 infection has been designed. The serum of vaccine immunized mice show potent ADCC activities in comparison with vector control group and HA ecto domain vaccinated group. However, the release of IL-6 and TNFα is higher in lung of epitope vaccine immunized mice. The viral load is also higher in epitope vaccine immunized mice. In addition, the epitope vaccine immunized mice showed lower survive rate than both empty vector immunized mice and HA ectodomain immunized mice. Passive transfer of serum from epitope vaccine immunized mice to healthy adult mice can decrease the survival rate of recipients after viral challenge. Our data suggested that ADCC epitope based vaccine has a mortality promoting effect rather than protective effect after H1N1 viral challenge. This result provides indications in future vaccine design with a consideration of balancing humoral immune response and cellular immune response.
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Citotoxicidade Celular Dependente de Anticorpos/imunologia , Epitopos/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae/imunologia , Vacinação/efeitos adversos , Animais , Linhagem Celular , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/virologia , Taxa de SobrevidaRESUMO
Prompt recognition of electrocardiographic signs of acute left anterior descending (LAD) occlusion is essential for timely restoration of flow. However, some patients may present with atypical electrocardiographic signs, and early diagnosis of these patients may constitute a clinical challenge. Here, we report two cases presenting with an atypical electrocardiographic manifestation despite angiographically confirmed acute thrombotic occlusion of proximal LAD. These cases highlight the importance of recognizing the de Winter electrocardiogram pattern in cases of suspected acute myocardial infarction (AMI). An emergency percutaneous coronary intervention (PCI) should be performed in suspected AMI patients as early as possible.
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Oclusão Coronária/fisiopatologia , Oclusão Coronária/cirurgia , Eletrocardiografia , Intervenção Coronária Percutânea , Adulto , Angiografia Coronária , Diagnóstico Diferencial , Humanos , Masculino , Exame FísicoRESUMO
BACKGROUND: Traditional Chinese herbal medicines (TCMs) have been widely used against a broad spectrum of biological activities, including influencing the cardiac differentiation from mouse embryonic stem cells (mESCs). However, their effects and mechanisms of action on ESCs proliferation remain to be determined. The present study aimed to determine the effect of three TCMs, baicalin, ginsenoside Rg1, and puerarin, on mESCs proliferation and to elucidate the possible mechanism of their action. METHODS: Cell proliferation was examined with a cell proliferation assay Cell Counting Kit-8 (CCK-8), propidium iodide (PI) staining was used to visualize cell cycle. The mRNA expression level of c-myc, c-fos, c-jun, GAPDH and microRNAs were measured by quantitative real time RT-PCR. RESULTS: We found that baicalin 50 µM suppressed the proliferation of mESCs as observations in more cells in G1 phase and less cells in either S phase or G2/M phase. Moreover, baicalin suppressed the expressions of c-jun and c-fos in mESCs and down-regulated the expression of miR-294. Overexpression of miR-294 in mESCs significantly reversed the effects of baicalin both on mESC proliferation and c-fos/c-jun expression. CONCLUSIONS: Baicalin down-regulation of miR-294 may be its key mechanism of action in decreasing mESCs proliferation.
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Proliferação de Células/efeitos dos fármacos , Flavonoides/farmacologia , MicroRNAs/metabolismo , Animais , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Medicina Tradicional Chinesa , Camundongos , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismoRESUMO
Stromata occasionally are observed in Achnatherum sibiricum distributed in northern China. However, endophyte species that form stromata on that host have not been studied. Here we identified the first Epichloë sp. endophyte in stroma-bearing A. sibiricum. Isolated colonies of this Epichloë sp. were smoother and more compact than previously described for Epichloë gansuensis and also had longer phialides and faster growth in culture. However, phylogenetic relationships based on intron sequences of genes encoding ß-tubulin (tubB) and translation elongation factor 1-α (tefA) grouped all isolates from the stromata in a clade with a close relationship to E. gansuensis. We identified the new isolates as E. gansuensis. The analysis of the stromata revealed no perithecium or ascospores during morphological and paraffin section observation. Furthermore, the ability of conidia formed on stromata to germinate and initiate infection of new seedlings was tested. After 3 mo 20% endophyte-free seedlings became infected by E. gansuensis, whereas the control group showed no endophyte infection. The results indicated the potential of cultures from conidia to mediate horizontal transmission.
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Endófitos/isolamento & purificação , Epichloe/isolamento & purificação , Doenças das Plantas/microbiologia , Poaceae/microbiologia , Esporos Fúngicos/fisiologia , China , Endófitos/classificação , Endófitos/genética , Endófitos/fisiologia , Epichloe/classificação , Epichloe/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Dados de Sequência Molecular , Fator 1 de Elongação de Peptídeos/genética , Fator 1 de Elongação de Peptídeos/metabolismo , Filogenia , Esporos Fúngicos/classificação , Esporos Fúngicos/genética , Esporos Fúngicos/isolamento & purificaçãoRESUMO
OBJECTIVE: To explore the characteristics of cognitive impairment in depressive elders in Shanghai. METHODS: A total of 1 068 participants randomly selected from 4 communities in Shanghai underwent neuropsychiatric and psychiatrists clinical assessment. Among them, 102 depressive ones with a score of geriatric depression scale (GDS) > 10 and 102 non-depressive ones with a score of GDS ≤ 10 were selected as depression and non-depression groups respectively. The SPSS statistic software V17.0 was used. RESULTS: Significant differences existed between the depressive and non-depressive patients in the total score of Montreal Cognitive Assessment (MoCA) (t = 2.353), trail making B task (t = 2.236), attention (t = 2.621), sustained attention (t = 2.381), calculation (t = 2.612) and fixed orientation (t = 2.259) (P < 0.05). The negative correlation had significant inter-group differences in the total score of MoCA (r = -0.142), attention (r = -0.161), sustained attention (r = -0.160), calculation (r = -0.150), fluency (r = -0.156), delayed recall (r = -0.175) and orientation to place (r = -0.172) (P < 0.05). Cognitive impairment in depression group had lower scores than non-depression group in the total score MoCA (14.9 ± 7.3 vs 17.5 ± 6.7), attention (1.1 ± 0.8 vs 1.4 ± 0.8), calculation (1.9 ± 1.2 vs 2.3 ± 1.1) and fixed orientation (1.7 ± 0.7 vs 1.8 ± 0.5) (P < 0.05). CONCLUSION: In depressive elders, cognitive impairment occurs in multiple cognitive domains of attention, executive function and orientation to place. There is a negative correlation between GDS score and MoCA. The higher GDS score, the worse cognitive function.
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Transtornos Cognitivos , Depressão , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Humanos , MasculinoRESUMO
Fungal symbionts can improve plant tolerance to salt stress. However, the interaction of epiphytic Fusarium oxysporum and Fusarium fujikuroi with the tolerance of the invasive plant Ipomoea cairica against saline coastal habitats is largely unknown. This study aimed to investigate the interaction of the mixture of the two epiphytic fungi with salt tolerance of I. cairica. Surface-sterilized I. cairica cuttings inoculated (E+) and non-inoculated (E-) with the fungal mixture were cultivated with 2, 3, and 5 parts per thousand (PPT) of NaCl solutions to simulate mild, moderate, and severe salt stress, respectively. The hydroponic experiment showed that the growth inhibition and peroxidation damages of E+ and E- cuttings were aggravated with salinity. Noteworthily, E+ cuttings had higher peroxidase (POD) and catalase (CAT) activities, chlorophyll content, total biomass, aboveground biomass, total shoot length and secondary shoot number, but lower root-to-shoot ratio than E- cuttings under 2 and 3 PPT NaCl conditions. Moreover, E+ had higher superoxide dismutase (SOD) activity and proline content but lower belowground biomass and malondialdehyde (MDA) content than E- cuttings under 3 PPT NaCl condition. However, lower SOD, POD, and CAT activities, and chlorophyll content, but higher MDA content occurred in E+ cuttings than in E- cuttings under 5 PPT NaCl condition. These findings suggested that the mixture of the two epiphytic fungi increased salt tolerance of I. cairica mainly through increasing its antioxidation ability and chlorophyll stability under mildly and moderately saline conditions, but decreased salt tolerance of this plant in an opposite way under severely saline conditions.
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Ipomoea , Tolerância ao Sal , Estresse Fisiológico/fisiologia , Cloreto de Sódio/farmacologia , Clorofila , Antioxidantes , Peroxidase , Superóxido DismutaseRESUMO
Food and predators are the most noteworthy objects for the basic survival of wild animals, and both are often deviant in both spatial and temporal domains and quickly attract an animal's attention. Although stimulus-specific adaptation (SSA) is considered a potential neural basis of salient sound detection in the temporal domain, related research on visual SSA is limited and its relationship with temporal saliency is uncertain. The avian nucleus isthmi pars magnocellularis (Imc), which is central to midbrain selective attention network, is an ideal site to investigate the neural correlate of visual SSA and detection of a salient object in the time domain. Here, the constant order paradigm was applied to explore the visual SSA in the Imc of pigeons. The results showed that the firing rates of Imc neurons gradually decrease with repetitions of motion in the same direction, but recover when a motion in a deviant direction is presented, implying visual SSA to the direction of a moving object. Furthermore, enhanced response for an object moving in other directions that were not presented ever in the paradigm is also observed. To verify the neural mechanism underlying these phenomena, we introduced a neural computation model involving a recoverable synaptic change with a "center-surround" pattern to reproduce the visual SSA and temporal saliency for the moving object. These results suggest that the Imc produces visual SSA to motion direction, allowing temporal salient object detection, which may facilitate the detection of the sudden appearance of a predator.
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Mesencéfalo , Neurônios , Animais , Mesencéfalo/fisiologia , Neurônios/fisiologia , Columbidae , Estimulação LuminosaRESUMO
Birds have developed visual cognitions, especially in discriminating colors due to their four types of cones in the retina. The entopallium of birds is thought to be involved in the processing of color information during visual cognition. However, there is a lack of understanding about how functional connectivity in the entopallium region of birds changes during color cognition, which is related to various input colors. We therefore trained pigeons to perform a delayed color matching task, in which two colors were randomly presented in sample stimuli phrases, and the neural activity at individual recording site and the gamma band functional connectivity among local population in entopallium during sample presentation were analyzed. Both gamma band energy and gamma band functional connectivity presented dynamics as the stimulus was presented and persisted. The response features in the early-stimulus phase were significantly different from those of baseline and the late-stimulus phase. Furthermore, gamma band energy showed significant differences between different colors during the early-stimulus phase, but the global feature of the gamma band functional network did not. Further decoding results showed that decoding accuracy was significantly enhanced by adding functional connectivity features, suggesting the global feature of the gamma band functional network did not directly contain color information, but was related to it. These results provided insight into information processing rules among local neuronal populations in the entopallium of birds during color cognition, which is important for their daily life.
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[This corrects the article DOI: 10.1007/s11571-022-09916-w.].
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BACKGROUND: Stem cell therapy has been proposed as a potential treatment strategy for ischemic cardiomyopathy in recent years. A variety of stem cells or stem cell-derived cells can potentially be used for transplantation. Despite improved cardiac function after treatment, one of the major problems is the poor integration between host and donor cells which can lead to post-transplantation arrhythmia and poor long-term outcome. METHODS: In the present study, we cocultured murine embryonic stem cells (mES) with murine embryonic ventricular myocytes (mEVs) in hanging drops to assess the cellular interaction and function of mES-derived cardiomyocytes under these conditions. RESULTS: We found that when mEVs are added to a culture system of embryonic stem cells, the number of spontaneously beating areas in embryoid bodies (EBs) increases, intercellular gap junction communication is enhanced by upregulation of Cx43 expression at the mid-developmental stage and Cx43 is distributed more orderly between cardiomyocytes. CONCLUSIONS: Our findings suggest mES-derived cardiomyocytes are able to form effective signaling pathways through coculture with mEVs which is important for providing more functional grafts for cardiac cell therapy by improving the integration between transplanted and host cells.
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Conexina 43/metabolismo , Células-Tronco Embrionárias/citologia , Miócitos Cardíacos/citologia , Animais , Diferenciação Celular , Células Cultivadas , Técnicas de Cocultura , Conexina 43/genética , Corpos Embrioides , Células-Tronco Embrionárias/metabolismo , Camundongos , Miócitos Cardíacos/metabolismo , RNA Mensageiro/metabolismo , Transdução de Sinais , Troponina T/metabolismo , Regulação para CimaRESUMO
BACKGROUND: To assess the reliability, validity, and diagnostic utility of the Chinese version of General Practitioner Assessment of Cognition (GPCOG-C). The GPCOG, which is specifically designed for use in primary care to screen for cognitive impairment, consists of a patient section testing cognition, and an informant section asking about decline in cognitive and functional abilities. METHODS: The English version of GPCOG was translated, back-translated, and subsequently revised to determine the final GPCOG-C. Our sample comprised 253 community-dwelling volunteers with memory concerns aged 50 years and over and 103 outpatients of a psychogeriatric clinic with memory complaints. Participants were assessed by one of the four general practitioners or six psychogeriatricians. The Mini-Mental State Examination (MMSE), the Hasegawa's Dementia Scale (HDS), and the GPCOG-C were compared against the DSM-IV-defined dementia diagnosis. RESULTS: The internal consistency (Cronbach's α) was 0.68 for the GPCOG patient section. The test-retest was 0.98 for the GPCOG-C total. The sequential administration of both components of GPCOG-C had a sensitivity of 97% and a specificity of 89%, with a positive predictive value of 72% and a negative predictive value of 99%. Both the GPCOG-C total and sequential two-stage scoring methods performed at least well as the MMSE and HDS in detecting dementia. The administration time for the two-stage approach was 4.3 ± 2.4 min. CONCLUSIONS: The GPCOG-C is a valid, time efficient instrument for dementia screening in China.
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Transtornos Cognitivos/diagnóstico , Medicina Geral/métodos , Testes Neuropsicológicos , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Demência/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , TraduçãoRESUMO
Multivariate time series (MTS) play essential roles in daily life because most real-world time series datasets are multivariate and rich in time-dependent information. Traditional forecasting methods for MTS are time-consuming and filled with complicated limitations. One efficient method being explored within the dynamical systems is the extended short-term memory networks (LSTMs). However, existing MTS models only partially use the hidden spatial relationship as effectively as LSTMs. Shallow LSTMs are inadequate in extracting features from high-dimensional MTS; however, the multilayer bidirectional LSTM (BiLSTM) can learn more MTS features in both directions. This study tries to generate a novel and improved BiLSTM network (DBI-BiLSTM) based on a deep belief network (DBN), bidirectional propagation technique, and a chained structure. The deep structures are constructed by a DBN layer and multiple stacked BiLSTM layers, which increase the feature representation of DBI-BiLSTM and allow for the model to further learn the extended features in two directions. First, the input is processed by DBN to obtain comprehensive features. Then, the known features, divided into clusters based on a global sensitivity analysis method, are used as the inputs of every BiLSTM layer. Meanwhile, the previous outputs of the shallow layer are combined with the clustered features to reconstitute new input signals for the next deep layer. Four experimental real-world time series datasets illustrate our one-step-ahead prediction performance. The simulating results confirm that the DBI-BiLSTM not only outperforms the traditional shallow artificial neural networks (ANNs), deep LSTMs, and some recently improved LSTMs, but also learns more features of the MTS data. As compared with conventional LSTM, the percentage improvement of DBI-BiLSTM on the four MTS datasets is 85.41, 75.47, 61.66 and 30.72%, respectively.