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1.
J Neurosci ; 44(3)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-37985178

RESUMO

The dorsomedial posterior parietal cortex (dmPPC) is part of a higher-cognition network implicated in elaborate processes underpinning memory formation, recollection, episode reconstruction, and temporal information processing. Neural coding for complex episodic processing is however under-documented. Here, we recorded extracellular neural activities from three male rhesus macaques (Macaca mulatta) and revealed a set of neural codes of "neuroethogram" in the primate parietal cortex. Analyzing neural responses in macaque dmPPC to naturalistic videos, we discovered several groups of neurons that are sensitive to different categories of ethogram items, low-level sensory features, and saccadic eye movement. We also discovered that the processing of category and feature information by these neurons is sustained by the accumulation of temporal information over a long timescale of up to 30 s, corroborating its reported long temporal receptive windows. We performed an additional behavioral experiment with additional two male rhesus macaques and found that saccade-related activities could not account for the mixed neuronal responses elicited by the video stimuli. We further observed monkeys' scan paths and gaze consistency are modulated by video content. Taken altogether, these neural findings explain how dmPPC weaves fabrics of ongoing experiences together in real time. The high dimensionality of neural representations should motivate us to shift the focus of attention from pure selectivity neurons to mixed selectivity neurons, especially in increasingly complex naturalistic task designs.


Assuntos
Neurônios , Movimentos Sacádicos , Animais , Masculino , Macaca mulatta , Neurônios/fisiologia , Cognição , Lobo Parietal/fisiologia
2.
Appl Environ Microbiol ; 90(4): e0204323, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38547470

RESUMO

Pasteurella multocida is a zoonotic conditional pathogen that infects multiple livestock species, causing substantial economic losses in the animal husbandry industry. An efficient markerless method for gene manipulation may facilitate the investigations of P. multocida gene function and pathogenesis of P. multocida. Herein, a temperature-sensitive shuttle vector was constructed using lacZ as a selection marker, and markerless glgB, opa, and hyaE mutants of P. multocida were subsequently constructed through blue-white colony screening. The screening efficiency of markerless deletion strains was improved by the lacZ system, and the method could be used for multiple gene deletions. However, the fur mutant was unavailable via this method. Therefore, we constructed a pheSm screening system based on mutated phenylalanine tRNA synthetase as a counterselection marker to achieve fur deletion mutant. The transformed strain was sensitive to 20 mM p-chloro-phenylalanine, demonstrating the feasibility of pheSm as a counter-selective marker. The pheSm system was used for markerless deletions of glgB, opa, and hyaE as well as fur that could not be screened by the lacZ system. A comparison of screening efficiencies of the system showed that the pheSm counterselection system was more efficient than the lacZ system and broadly applicable for mutant screening. The methods developed herein may provide valuable tools for genetic manipulation of P. multocida.IMPORTANCEPasteurella multocida is a highly contagious zoonotic pathogen. An understanding of its underlying pathogenic mechanisms is of considerable importance and requires efficient species-specific genetic tools. Herein, we propose a screening system for P. multocida mutants using lacZ or pheSm screening markers. We evaluated the efficiencies of both systems, which were used to achieve markerless deletion of multiple genes. The results of this study support the use of lacZ or pheSm as counterselection markers to improve counterselection efficiency in P. multocida. This study provides an effective genetic tool for investigations of the virulence gene functions and pathogenic mechanisms of P. multocida.


Assuntos
Pasteurella multocida , Animais , Pasteurella multocida/genética , Óperon Lac , Vetores Genéticos , Fenilalanina
3.
Macromol Rapid Commun ; : e2400372, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38885423

RESUMO

Stimuli-responsive block copolymer nanoparticles (NPs) have received close attention in recent years owing to their tremendous application potential in smart materials. Azobenzene-containing NPs are widely studied due to the advantages of light as a stimulus and fast reversible trans-cis isomerization of azobenzene chromophores. However, the inefficient preparation process and difficult reversible transformation of morphologies limit their development. Herein it is demonstrated that the light-triggered reversible swelling behavior of wormlike NPs with high azobenzene content could be realized via confined deformation. These worms are prepared in large quantities via polymerization-induced self-assembly based on the copolymerization of 11-(4-(4-butylphenylazo)phenoxy)undecyl methacrylate (MAAz) and N-(methacryloxy)succinimide (NMAS) monomers. Upon UV/visible light irradiation, the reversible deformation of worms is achieved when the feed molar ratio of NMAS/MAAz is relatively high or via crosslinking using diamines, which leads to the reduction of the photoisomerization efficiency. The diameter variation of the worms is influenced by the amount and types of crosslinkers. Moreover, the scalability of this strategy is further proved by the fabrication of photo- and reductant-responsive crosslinked worms. It is expected that this study not only provides a new route to affording reversible photoresponsive NPs but also offers a unique insight into the reversible photodeformation mechanism of azobenzene-containing NPs.

4.
Macromol Rapid Commun ; 45(11): e2400021, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38456737

RESUMO

Flexible ultraviolet (UV) light detection technology has important applications in wearable devices, smart sensors, and other fields and attracts much attention in recent years. However, for most semiconductor-based UV detectors, the elastic modulus between rigid semiconductors and flexible substrates is mismatched, which makes it difficult to fabricate UV detectors that meet the needs of wearable devices. Herein, a fully flexible, large-scale, skin-friendly UV photodetector component centered on photo-responsive worm-like polymer nanoparticles (NPs) is developed, and the resulting device can quantitatively detect UV illumination. Skin-friendly poly(vinyl alcohol) (PVA), amphiphilic azobenzene-containing polymer NPs (AzNPs), and water-soluble ionic liquids (IL) are formed into (AzNPs-IL)/PVA fabrics by electrospinning. There are interactions such as hydrogen bonding among PVA, AzNPs, and IL, which make the material system stable. The UV detector made of the fabric realizes UV sensing through the illuminance-mechanical stress-electrical signal conversion mechanism. It is capable of achieving a response time of 9 s, a detection range of 10-150 mW cm-2, and stability for 1000 cycle tests upon 365 nm UV irradiation. Moreover, it has good skin affinity, and the water contact angle of the fabric is only 23.57°, which holds great promise for wearable smart devices.


Assuntos
Nanopartículas , Polímeros , Raios Ultravioleta , Dispositivos Eletrônicos Vestíveis , Nanopartículas/química , Polímeros/química , Álcool de Polivinil/química , Pele/química , Humanos , Líquidos Iônicos/química , Compostos Azo/química
5.
Chemistry ; 29(28): e202300438, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-36843339

RESUMO

Responsive photonic crystals (RPCs) assembled by monodisperse colloidal particles have attracted enormous interest recently due to their tremendous applications in smart devices. Their structural colors can be determined by particle sizes. However, the lack of a reliable way to tune the sizes in situ limits their development. Herein, we present an efficient route to solve this problem through the fabrication of spherical polymeric particles with light-triggered reversible swelling behavior via surfactant-free reversible addition-fragmentation chain transfer (RAFT) emulsion polymerization-induced self-assembly (PISA). Amphiphilic macro-RAFT agents containing azobenzene groups were synthesized and subsequently employed to mediate the polymerization of methyl methacrylate. Uniform submicron spheres were obtained by modulating solid contents and other parameters. Benefiting from the photoisomerization of azobenzene moieties, the particle sizes expanded and contracted upon alternative ultraviolet/visible-light irradiation accordingly. This strategy will be a supplement to the emulsion PISA and especially give aid to the progress of the RPC materials.

6.
Macromol Rapid Commun ; 44(21): e2300361, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37534616

RESUMO

Polymerization-induced self-assembly incorporating liquid crystallization, as a polymerization-induced hierarchical self-assembly (PIHSA) method to produce polymeric particles with anisotropic morphologies facilely and efficiently, has drawn wide attention recently. However, the means of regulating the morphologies of liquid crystalline (LC) polymer assemblies still need to be explored. Herein, a route is presented to fabricate the twisted ribbons via PIHSA containing azobenzene based on poor reversible addition-fragmentation chain transfer (RAFT) control, called poorly controlled PIHSA. Cyano-4-(dodecylsulfanylthiocarbonyl)sulfanyl pentanoic acid-2-(2-pyridyldithio) ethyl ester is used as the RAFT agent with poor controllability, and the morphological evolution from ribbons to twisted ribbons can be observed in the corresponding PIHSA system. The formation mechanism of the twisted ribbons is studied systematically and the broad molecular weight distribution is considered to be the decisive factor. Moreover, the supramolecular chirality induced by symmetry breaking is also related to the twist of the ribbons. This study enriches the methods of controlling the morphologies of LC polymer particles and is helpful for further clarifying the mechanism of PIHSA.


Assuntos
Compostos Azo , Polímeros , Polimerização , Polímeros/química , Cristalização
7.
BMC Oral Health ; 23(1): 507, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37480059

RESUMO

OBJECTIVE: To explore the effect of children's migration on their oral health outcomes in multi-beneficial kindergartens in Jiangnan District, Nanning, China, and to provide a basis for improving the oral health of migrant children. METHODS: A cross-sectional study was conducted among 470 children aged 5 years in Jiangnan District, Nanning, Guangxi. A questionnaire was used to collect information on their demographic and socioeconomic background, migration experience, eating habits, oral hygiene behaviours and utilization of dental care services. Dental caries of primary teeth was examined using the decayed, missing, and filled teeth (dmft) index recommended by the World Health Organization. Dental caries experience and oral health-related behaviours were compared between migrant and resident children. The impact of children's migration attributes on their oral health outcomes was examined by univariate and multivariate analyses. RESULTS: Among the examined children, 52.3% were migrant children. The prevalence of caries among the children in multi-beneficial kindergartens was 78.3%, and the mean number of dmft was 5.73 ± 5.00. The prevalence of caries was 81.7% for migrant children and 74.6% for resident children (p = 0.060). No significant difference was found in the mean numbers of DMFT between migrant children and resident children (5.96 ± 4.81 vs. 5.47 ± 5.20, p = 0.139). There were significant differences in the frequency of tooth brushing (p = 0.023) and parental help with tooth brushing (p = 0.008), typical use of fluoride (p = 0.012), regular dental check-ups (p = 0.003) and experience of dental fillings for caries (p < 0.001) between migrant and resident children. The multivariate logistic regression analysis showed that among the children with caries, the proportion of resident children who had regular dental check-ups was 1.720 times higher than that of migrant children (95% CI = 1.155 ~ 2.560), and resident children were more likely to have caries filled than migrant children (OR = 3.313, 95% CI = 1.585 ~ 6.927). CONCLUSION: Oral health status and oral health behaviours were poor among children in multi-beneficial kindergartens in Nanning, China, and migration might be a significant predictive indicator for the poor utilization of dental care services by children. The government departments should make special policy to promote the children's oral health in multi-beneficial kindergartens, and invest more to cover the migrant children's utilization of oral health services.


Assuntos
Cárie Dentária , Humanos , Criança , Cárie Dentária/epidemiologia , Cárie Dentária/prevenção & controle , Estudos Transversais , China/epidemiologia , Saúde Bucal , Prevalência , Avaliação de Resultados em Cuidados de Saúde , Índice CPO
8.
J Neurosci ; 41(14): 3254-3265, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33622780

RESUMO

Perceptual decision-making is increasingly being understood to involve an interaction between bottom-up sensory-driven signals and top-down choice-driven signals, but how these signals interact to mediate perception is not well understood. The parieto-insular vestibular cortex (PIVC) is an area with prominent vestibular responsiveness, and previous work has shown that inactivating PIVC impairs vestibular heading judgments. To investigate the nature of PIVC's contribution to heading perception, we recorded extracellularly from PIVC neurons in two male rhesus macaques during a heading discrimination task, and compared findings with data from previous studies of dorsal medial superior temporal (MSTd) and ventral intraparietal (VIP) areas using identical stimuli. By computing partial correlations between neural responses, heading, and choice, we find that PIVC activity reflects a dynamically changing combination of sensory and choice signals. In addition, the sensory and choice signals are more balanced in PIVC, in contrast to the sensory dominance in MSTd and choice dominance in VIP. Interestingly, heading and choice signals in PIVC are negatively correlated during the middle portion of the stimulus epoch, reflecting a mismatch in the polarity of heading and choice signals. We anticipate that these results will help unravel the mechanisms of interaction between bottom-up sensory signals and top-down choice signals in perceptual decision-making, leading to more comprehensive models of self-motion perception.SIGNIFICANCE STATEMENT Vestibular information is important for our perception of self-motion, and various cortical regions in primates show vestibular heading selectivity. Inactivation of the macaque vestibular cortex substantially impairs the precision of vestibular heading discrimination, more so than inactivation of other multisensory areas. Here, we record for the first time from the vestibular cortex while monkeys perform a forced-choice heading discrimination task, and we compare results with data collected previously from other multisensory cortical areas. We find that vestibular cortex activity reflects a dynamically changing combination of sensory and choice signals, with both similarities and notable differences with other multisensory areas.


Assuntos
Comportamento de Escolha/fisiologia , Movimentos da Cabeça/fisiologia , Percepção de Movimento/fisiologia , Lobo Parietal/fisiologia , Córtex Somatossensorial/fisiologia , Vestíbulo do Labirinto/fisiologia , Animais , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Aprendizagem por Discriminação/fisiologia , Macaca mulatta , Imageamento por Ressonância Magnética/métodos , Masculino , Lobo Parietal/diagnóstico por imagem , Estimulação Luminosa/métodos , Córtex Somatossensorial/diagnóstico por imagem , Vestíbulo do Labirinto/diagnóstico por imagem
9.
Small ; 18(33): e2202639, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35871501

RESUMO

It is significantly challenging for state-of-the-art wearable electronics to stably monitor physicochemical signals under dynamic motions. Herein, a bending-insensitive, self-powered, and intrinsically flexible UV detector has been realized based on well-designed oriented composite fabrics, consisting of ionic liquid (IL)-containing liquid crystalline polymers (ILCPs) and piezoelectric poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] nanogenerators. The novel composite fabrics establish effective UV illuminance-internal stress-electric signal conversion by coupling resistive and piezoelectric effects, with a fast response time of 190 ms. Particularly, benefiting from the intrinsic flexibility of composite fabrics, the ILCP/P(VDF-TrFE) device can maintain stable performance under dynamic bending even if the frequency is up to 2.5 Hz, with a bending insensitivity of less than 1% performance variation under 1.0 mW cm-2 UV light. Combined with the Internet of Things and the American Standard Code for Information Interchange (ASCII), wearable encoding electronics have been successfully implemented with a printing speed of 3.2 s per character under dynamic bending.


Assuntos
Polímeros , Têxteis , Eletricidade , Eletrônica , Polímeros/química , Impressão Tridimensional
10.
BMC Cardiovasc Disord ; 22(1): 440, 2022 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-36210443

RESUMO

BACKGROUND: Atherogenic index of plasma (AIP) as a newly discovered blood lipid parameter was shown to be strongly correlated with coronary artery disease (CAD). However, the blood lipid levels changed with age, so we speculated that the correlation between AIP and CAD was also affected by age. METHODS: A retrospective study was performed on male patients with confirmed or suspected CAD who underwent coronary angiography (CAG) from July 2017 to March 2021. Patients were divided into younger, middle early, middle late, and elderly groups. Patients in each age group were further divided into the non-coronary artery disease (n-CAD) and CAD subgroups according to the CAG diagnostic results. The relationship between blood lipid parameters and CAD was assessed in each age group. RESULTS: Age-dependent changes of blood lipid levels were mainly found in CAD patients but not in n-CAD patients. With increased age, the levels of triglyceride, total cholesterol, low-density lipoprotein cholesterol (LDL-C) and AIP were gradually decreased, whereas high-density lipoprotein cholesterol concentration was increased in CAD patients. Multivariate logistic regression analyses showed that AIP was an independent risk factor for CAD in middle early (OR 2.601; CI 1.160-5.832, P = 0.02) and middle late age group (OR 2.707, CI 1.201-6.100, P = 0.016), but not in the younger and elderly groups. LDL-C was an independent risk factor for CAD in all age groups. The areas under curve of AIP for detecting CAD in the middle early and middle late age groups were not higher than that of other blood lipid parameters. CONCLUSION: Although this was a single-center study for males only, the correlation between AIP level and CAD risk was age-dependent. AIP was an independent risk factor for CAD in the middle-aged groups. However, the predictive value of AIP for detecting CAD was not better than that of the traditional blood lipid parameters such as LDL-C.


Assuntos
Doença da Artéria Coronariana , Idoso , Artérias , HDL-Colesterol , LDL-Colesterol , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico , Humanos , Lipídeos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Triglicerídeos
11.
Int J Mol Sci ; 23(23)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36499652

RESUMO

Phytochrome-interacting factors (PIFs) are transcription factors with the basic helix-loop-helix (bHLH) domain. As integration factors between different signal pathways, members of the PIF protein family regulate many aspects of plant growth and development, such as seed germination, photomorphogenesis, thermomorphogenesis, rhythm regulation, flowering response, stomatal development, and stress responses. Our previous studies have shown that the BpSPL2 gene may regulate plants' adventitious root development through PIF genes. Within the Betula platyphylla genome, we identified eight PIF (BpPIFs) genes. We analysed and named them based on a phylogenetic tree, gene structures, and conserved motifs. Synteny analysis indicated that transposition or segmental duplication events played a minor role in the expansion of BpPIFs. The comparative syntenic analysis combined with phylogenetic analysis provided a deep insight into the phylogenetic relationships of BpPIF genes, suggesting that BpPIF proteins are closer to PtPIF than to AtPIF. The analysis of cis-acting elements in promoter regions of BpPIF genes indicated that various elements were related to light, abiotic stress, and plant hormone responsiveness. In addition, we found that these promoters have the transcription factor of B. platyphylla SPL2 (BpSPL2) binding motif GTAC. Expression analysis demonstrated that BpPIF genes, especially BpPIF4, BpPIF9b, and BpPIF10, might be the potential target genes of BpSPL2 in the process of adventitious root formation. Besides providing a comprehensive understanding of the BpPIF family, we propose a hypothetical gene network regulatory model for adventitious root formation.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Filogenia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Crescimento e Desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
12.
BMC Oral Health ; 22(1): 471, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335309

RESUMO

BACKGROUND: Dental caries is one of the most prevalent chronic diseases worldwide among children. The rs35874116 single nucleotide polymorphism (SNP) in the sweet receptor gene TAS1R2 has been associated with dental caries at a high risk in permanent teeth among school children and adults. To date, little is known about the association of this SNP with sweet intake and caries risk in the primary school children. METHODS: Total of 236 children were included, namely 118 subjects in the non-caries (NC) group and severe early childhood caries (S-ECC) group, respectively. Oral mucosa cells were collected from all the selected children, and the full length of exon 3 in TAS1R2 was sequenced to analyse rs35874116 polymorphism. A questionnaire was used to collect information about socio-demographic information, frequency of sweet intake and oral hygiene habits. Multiple logistic regression models were applied to assess the relationship of rs35874116 polymorphism with frequency of sweet intake and S-ECC among the five-year-old children. RESULTS: Children with the TT genotype of rs35874116 had a higher frequency of sweet intake than CT/CC carriers (51.3% vs. 32.7%; x2 = 5.436, p = 0.020), and S-ECC individuals were more likely to be TT genotype carriers than NC individuals (53.5% vs. 46.5%; x2 = 4.353, p = 0.037). Multiple logistic regression analyses showed that the TT genotype of rs35874116 was not only significantly related to the frequency of sweet intake (OR = 2.25, 95% CI = 1.14-4.44) but also significantly associated with S-ECC (OR = 2.11, 95% CI = 1.01 ~ 4.42). CONCLUSIONS: The rs35874116 polymorphism might increase sweet intake and the risk of S-ECC among five-year-old children in Nanning, China.


Assuntos
Cárie Dentária , Criança , Pré-Escolar , Humanos , Estudos de Casos e Controles , China , Cárie Dentária/genética , Higiene Bucal , Polimorfismo de Nucleotídeo Único/genética
13.
J Physiol ; 599(16): 3937-3954, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34192812

RESUMO

KEY POINTS: Neurons in the posterior superior temporal polysensory area (STPp) showed significant directional selectivity in response to vestibular, optic flow and combined visual-vestibular stimuli. By comparison to the dorsal medial superior temporal area, the visual latency was slower in STPp but the vestibular latency was faster. Heading preferences under combined stimulation in STPp were usually dominated by visual signals. Cross-modal enhancement was observed in STPp when both vestibular and visual cues were presented together at their heading preferences. ABSTRACT: Human neuroimaging data implicated that the superior temporal polysensory area (STP) might be involved in vestibular-visual interaction during heading computations, but the heading selectivity has not been examined in the macaque. Here, we investigated the convergence of optic flow and vestibular signals in macaque STP by using a virtual-reality system and found that 6.3% of STP neurons showed multisensory responses, with visual and vestibular direction preferences either congruent or opposite in roughly equal proportion. The percentage of vestibular-tuned cells (18.3%) was much smaller than that of visual-tuned cells (30.4%) in STP. The vestibular tuning strength was usually weaker than the visual condition. The visual latency was significantly slower in STPp than in the dorsal medial superior temporal area (MSTd), but the vestibular latency was significantly faster than in MSTd. During the bimodal condition, STP cells' response was dominated by visual signals, with the visual heading preference not affected by the vestibular signals but the response amplitudes modulated by vestibular signals in a subadditive way.


Assuntos
Percepção de Movimento , Fluxo Óptico , Animais , Sinais (Psicologia) , Movimentos da Cabeça , Humanos , Macaca mulatta , Estimulação Luminosa
14.
J Physiol ; 599(22): 5061-5084, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34555188

RESUMO

The frontal eye field (FEF) is a key part of the oculomotor system, with dominant responses to the direction of single saccades. However, whether and how FEF contributes to sequential saccades remain largely unknown. By training rhesus monkeys to perform saccade sequences, we found sequence-related activities in FEF neurons, whose selectivity to saccade direction undergoes dynamic changes during sequential vs. single saccades. These sequence-related activities are context-dependent, exhibiting different firing activities during memory- vs. visually guided sequences. When the monkey was performing the sequential saccade task, the thresholds of microstimulation to evoke saccades in FEF were increased and the percentage of the successfully induced saccades was significantly reduced compared with the fixation condition. Pharmacological inactivation of FEF impaired the monkey's performance of previously learned sequential saccades, with different effects on the same actions depending on its position within the sequence. These results reveal the context-dependent, sequence-specific dynamic encoding of saccades in FEF, and underscore the crucial role of FEF in the planning and execution of sequential saccades. KEY POINTS: FEF neurons respond differently during sequential vs. single saccades Sequence-related FEF activity is context-dependent The microstimulation threshold in FEF was increased during the sequential task but the evoked saccade did not alter the sequence structure FEF inactivation severely impaired the performance of sequential saccades.


Assuntos
Lobo Frontal , Movimentos Sacádicos , Animais , Macaca mulatta , Neurônios
15.
J Sep Sci ; 44(20): 3870-3882, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34418890

RESUMO

An ecofriendly and efficient ultrasound-assisted deep eutectic solvents dispersive liquid-phase microextraction by solidifying the deep eutectic solvents-rich phase was developed to determine azoxystrobin, fludioxonil, epoxiconazole, cyprodinil, and prochloraz in fruit juices and tea drinks by high-performance liquid chromatography. A varieties of environmental hydrophobic deep eutectic solvents serving as extraction agents were prepared using L-menthol and decanoic acid as hydrogen-bond acceptor and hydrogen-bond donor, respectively. The deep eutectic solvents were ultrasonically dispersed in sample solutions, solidified in a freezer and easily harvested. The main variables were optimized by one-factor-at-a-time and response surface test. The new method performs well with relative recovery of 71.75-109.40%, linear range of 2.5-5000 µg/L (r ≥ 0.9968), detection limit of 0.75-8.45 µg/L, quantification limit of 2.5-25 µg/L,, and inter- and intraday relative standard deviations below 13.53 and 14.84%, respectively. As for the extraction mechanism, deep eutectic solvents were disposed into many fine particles in the solution and captured the analytes based on the changes of particle size and quantity in deep eutectic solvents droplets after extraction. The environmental method can successfully detect fungicide residues in real fruit juices and tea drinks.


Assuntos
Ácidos Decanoicos/química , Sucos de Frutas e Vegetais/análise , Fungicidas Industriais/análise , Microextração em Fase Líquida , Mentol/química , Chá/química , Ondas Ultrassônicas , Interações Hidrofóbicas e Hidrofílicas , Solventes/química
16.
Biol Res ; 54(1): 30, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34517910

RESUMO

OBJECTIVE: This study aims to identify the effect of miR-146a-5p on trophoblast cell invasion as well as the mechanism in preeclampsia (PE). METHODS: Expression levels of miR-146a-5p and Wnt2 in preeclamptic and normal placentae were quantified. Trophoblast cells (HTR-8) were separately transfected with miR-146a-5p mimic, miR-146a-5p inhibitor, pcDNA3.1-Wnt2 or sh-Wnt2, and then the expression levels of miR-146a-5p, Wnt2, and epithelial-mesenchymal transition (EMT)-related proteins (Vimentin, N-cadherin and E-cadherin) were measured. Moreover, the proliferative, migratory and invasive capacities of trophoblast cells were detected, respectively. Dual luciferase reporter assay determined the binding of miR-146a-5p and Wnt2. RESULTS: Compared with normal placental tissues, the placentae from PE patients showed higher miR-146a-5p expression and lower Wnt2 expression. Transfection of miR-146a-5p inhibitor or pcDNA3.1-Wnt2 exerted pro-migratory and pro-invasive effects on HTR-8 cells and encouraged EMT in HTR-8 cells; transfection with miR-146a-5p mimic or sh-Wnt2 weakened the proliferative, migratory and invasive capacities as well as reduced EMT process of HTR-8 cells. Moreover, Wnt2 overexpression could partially counteract the suppressive effects of miR-146a-5p overexpression on the progression and EMT of HTR-8 cells. CONCLUSION: miR-146a-5p mediates trophoblast cell proliferation and invasion through regulating Wnt2 expression.


Assuntos
Transição Epitelial-Mesenquimal , MicroRNAs , Pré-Eclâmpsia , Trofoblastos/citologia , Movimento Celular , Proliferação de Células , Feminino , Humanos , MicroRNAs/genética , Placenta , Gravidez
17.
Vet Res ; 51(1): 97, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32736655

RESUMO

Lipooligosaccharides (LOSs) are virulence determinants of Glaesserella parasuis, a pathogen of the respiratory tract of pigs. We previously reported that disruption of the galU or galE gene in G. parasuis results in increased sensitivity to porcine serum, indicating that the galactose catabolism pathway is required for polysaccharide formation in G. parasuis. Here, we evaluated the role of the HAPS_0849 gene in LOS synthesis. The G. parasuis SC096 HAPS_0849 mutant produced a highly truncated LOS molecule, although a small fraction of intact LOS was still observed, and this mutant was found to be more sensitive to serum than the parental strain. HAPS_0849 was overexpressed and purified for biochemical assays, and this protein exhibited phosphoglucomutase (PGM) activity. Heterologous expression of a pgm gene from Escherichia coli in the HAPS_0849 mutant led to restoration of the wild-type LOS glycoform, further demonstrating the PGM function of HAPS_0849 in G. parasuis. The autoagglutination and biofilm formation ability of this strain were also investigated. Disruption of HAPS_0849 led to an increased tendency to autoagglutinate and form more biofilms, and these enhanced phenotypes were observed in the absence of glucose. In addition, LOSs from HAPS_0849, galU and lgtB mutants had similar truncated glycoforms, while LOSs from the galE and lex-1 mutants exhibited another type of defective LOS pattern. These findings imply that HAPS_0849 may function upstream of GalU in the generation of glucose 1-phosphate. In conclusion, our results preliminarily described the functions of HAPS_0849 in G. parasuis, and this gene was partially required for LOS synthesis.


Assuntos
Proteínas de Bactérias/genética , Haemophilus parasuis/genética , Lipopolissacarídeos/biossíntese , Fosfoglucomutase/genética , Proteínas de Bactérias/metabolismo , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Haemophilus parasuis/enzimologia , Microrganismos Geneticamente Modificados/genética , Fosfoglucomutase/metabolismo
18.
Int Wound J ; 17(5): 1300-1309, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32396265

RESUMO

Since December 2019, the medical staff fighting against COVID-19 frequently reported the device-related pressure injury (DRPI) caused by personal protective equipment (PPE). We conducted a cross-sectional survey online to investigate the prevalence and characteristics of DRPI among medical staff. Univariate and multivariate logistic regression analyses were employed to explore the risk factors associated with DRPI. A total of 4308 participants were collected and 4306 participants were valid from 161 hospitals in China. The overall prevalence of DRPI caused by PPE among medical staff was 30.03% (95% CI 28.69%-31.41%). The prevalence of male was more than that of female (42.25%, 95% CI 37.99-46.51% vs 26.36%, 95% CI 26.93-29.80%, P < .001).The categories were mainly stages 1 and 2, and the common anatomical locations were nose bridge, cheeks, ears, and forehead. Logistic regression analysis revealed that the risk factors were sweating (OR = 43.99, 95% CI 34.46-56.17), male (OR = 1.50, 95% CI 1.12-1.99), level 3 PPE (OR = 1.44, 95% CI 1.14-1.83), and longer wearing time (OR = 1.28, 95% CI 0.97-1.68). The prevalence of DRPI was high among medical staff wearing PPE against COVID-19, and the risk factors were sweating, male, wearing level 3 PPE, and longer wearing time. Comprehensive preventive interventions should be taken.


Assuntos
COVID-19/prevenção & controle , Corpo Clínico Hospitalar , Recursos Humanos de Enfermagem Hospitalar , Traumatismos Ocupacionais/etiologia , Equipamento de Proteção Individual/efeitos adversos , Úlcera por Pressão/etiologia , Adulto , COVID-19/transmissão , China/epidemiologia , Estudos Transversais , Transmissão de Doença Infecciosa/prevenção & controle , Traumatismos Faciais/etiologia , Feminino , Humanos , Masculino , Prevalência , Fatores de Risco , Fatores Sexuais , Inquéritos e Questionários , Sudorese , Fatores de Tempo
19.
Small ; 15(16): e1900110, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30913373

RESUMO

Crosslinked liquid crystalline polymers (CLCPs) have garnered extensive attention in recent years for their significant values in the design of light-driven soft actuators. However, poor processabilities due to the insoluble and infusible crosslinked networks prevent their practical applications severely. In this study, a weldable azobenzene-containing CLCP is designed with photo- and humidity-responsive actuations, which enables a cut-and-weld process to 3D CLCP architectures. The tensile properties and stability are almost unchanged after welding, much better than those of the films pasted by common adhesive tapes. Meanwhile, the mechanisms of the welding process are clarified on the base of surface hydrogen bonding and further crosslinking. By taking advantage of the cut-and-weld process, a 3D "claw" integrated into a robotic arm is realized for grabbing millimeter-scale objects by remote control. This work enhances significantly not only the processability of CLCP films but also the utilization of leftover pieces, which provides an efficient approach to create functional 3D structures from film precursors for the potential application in the smart materials.

20.
J Neurophysiol ; 119(3): 1113-1126, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29187554

RESUMO

The ventral intraparietal area (VIP) of the macaque brain is a multimodal cortical region, with many cells tuned to both optic flow and vestibular stimuli. Responses of many VIP neurons also show robust correlations with perceptual judgments during a fine heading discrimination task. Previous studies have shown that heading tuning based on optic flow is represented in a clustered fashion in VIP. However, it is unknown whether vestibular self-motion selectivity is clustered in VIP. Moreover, it is not known whether stimulus- and choice-related signals in VIP show clustering in the context of a heading discrimination task. To address these issues, we compared the response characteristics of isolated single units (SUs) with those of the undifferentiated multiunit (MU) activity corresponding to several neighboring neurons recorded from the same microelectrode. We find that MU activity typically shows selectivity similar to that of simultaneously recorded SUs, for both the vestibular and visual stimulus conditions. In addition, the choice-related activity of MU signals, as quantified using choice probabilities, is correlated with the choice-related activity of SUs. Overall, these findings suggest that both sensory and choice-related signals regarding self-motion are clustered in VIP. NEW & NOTEWORTHY We demonstrate, for the first time, that the vestibular tuning of ventral intraparietal area (VIP) neurons in response to both translational and rotational motion is clustered. In addition, heading discriminability and choice-related activity are also weakly clustered in VIP.


Assuntos
Comportamento de Escolha , Percepção de Movimento/fisiologia , Neurônios/fisiologia , Lobo Parietal/fisiologia , Vestíbulo do Labirinto/fisiologia , Animais , Macaca mulatta , Masculino , Estimulação Luminosa
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