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1.
PLoS Biol ; 21(3): e3002014, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36888690

RESUMO

A growing body of research demonstrates that distracting inputs can be proactively suppressed via spatial cues, nonspatial cues, or experience, which are governed by more than one top-down mechanism of attention. However, how the neural mechanisms underlying spatial distractor cues guide proactive suppression of distracting inputs remains unresolved. Here, we recorded electroencephalography signals from 110 participants in 3 experiments to identify the role of alpha activity in proactive distractor suppression induced by spatial cues and its influence on subsequent distractor inhibition. Behaviorally, we found novel changes in the spatial proximity of the distractor: Cueing distractors far away from the target improves search performance for the target, while cueing distractors close to the target hampers performance. Crucially, we found dynamic characteristics of spatial representation for distractor suppression during anticipation. This result was further verified by alpha power increased relatively contralateral to the cued distractor. At both the between- and within-subjects levels, we found that these activities further predicted the decrement of the subsequent PD component, which was indicative of reduced distractor interference. Moreover, anticipatory alpha activity and its link with the subsequent PD component were specific to the high predictive validity of distractor cue. Together, our results reveal the underlying neural mechanisms by which cueing the spatial distractor may contribute to reduced distractor interference. These results also provide evidence supporting the role of alpha activity as gating by proactive suppression.


Assuntos
Sinais (Psicologia) , Eletroencefalografia , Humanos , Atenção/fisiologia , Inibição Psicológica , Tempo de Reação/fisiologia , Percepção Visual/fisiologia
2.
Cereb Cortex ; 34(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38700440

RESUMO

While the auditory and visual systems each provide distinct information to our brain, they also work together to process and prioritize input to address ever-changing conditions. Previous studies highlighted the trade-off between auditory change detection and visual selective attention; however, the relationship between them is still unclear. Here, we recorded electroencephalography signals from 106 healthy adults in three experiments. Our findings revealed a positive correlation at the population level between the amplitudes of event-related potential indices associated with auditory change detection (mismatch negativity) and visual selective attention (posterior contralateral N2) when elicited in separate tasks. This correlation persisted even when participants performed a visual task while disregarding simultaneous auditory stimuli. Interestingly, as visual attention demand increased, participants whose posterior contralateral N2 amplitude increased the most exhibited the largest reduction in mismatch negativity, suggesting a within-subject trade-off between the two processes. Taken together, our results suggest an intimate relationship and potential shared mechanism between auditory change detection and visual selective attention. We liken this to a total capacity limit that varies between individuals, which could drive correlated individual differences in auditory change detection and visual selective attention, and also within-subject competition between the two, with task-based modulation of visual attention causing within-participant decrease in auditory change detection sensitivity.


Assuntos
Atenção , Percepção Auditiva , Eletroencefalografia , Percepção Visual , Humanos , Atenção/fisiologia , Masculino , Feminino , Adulto Jovem , Adulto , Percepção Auditiva/fisiologia , Percepção Visual/fisiologia , Estimulação Acústica/métodos , Estimulação Luminosa/métodos , Potenciais Evocados/fisiologia , Encéfalo/fisiologia , Adolescente
3.
J Transl Med ; 22(1): 720, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103842

RESUMO

BACKGROUND: Fatigue is one of the most common neurological symptoms reported post coronavirus disease 2019 (COVID-19) infection. In order to establish effective early intervention strategies, more emphasis should be placed on the correlation between fatigue and cortical neurophysiological changes, especially in healthcare workers, who are at a heightened risk of COVID-19 infection. METHODS: A prospective cohort study was conducted involving 29 COVID-19 medical workers and 24 healthy controls. The assessment included fatigue, sleep and health quality, psychological status, and physical capacity. Functional near-infrared spectroscopy (fNIRS) was employed to detect activation of brain regions. Bilateral primary motor cortex (M1) excitabilities were measured using single- and paired-pulse transcranial magnetic stimulation. Outcomes were assessed at 1, 3, and 6 months into the disease course. RESULTS: At 1-month post-COVID-19 infection, 37.9% of patients experienced severe fatigue symptoms, dropping to 10.3% at 3 months. Interestingly, the remarkable decreased activation/excitability of bilateral prefrontal lobe (PFC) and M1 were closely linked to fatigue symptoms after COVID-19. Notably, greater increase in M1 region excitability correlated with more significant fatigue improvement. Re-infected patients exhibited lower levels of brain activation and excitability compared to single-infection patients. CONCLUSIONS: Both single infection and reinfection of COVID-19 lead to decreased activation and excitability of the PFC and M1. The degree of excitability improvement in the M1 region correlates with a greater recovery in fatigue. Based on these findings, targeted interventions to enhance and regulate the excitability of M1 may represent a novel strategy for COVID-19 early rehabilitation. TRIAL REGISTRATION: The Ethics Review Committee of Xijing Hospital, No. KY20232051-F-1; www.chictr.org.cn , ChiCTR2300068444.


Assuntos
COVID-19 , Fadiga , Pessoal de Saúde , Córtex Motor , Córtex Pré-Frontal , Estimulação Magnética Transcraniana , Humanos , COVID-19/fisiopatologia , Fadiga/fisiopatologia , Masculino , Feminino , Estudos Longitudinais , Adulto , Córtex Pré-Frontal/fisiopatologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Motor/fisiopatologia , Pessoa de Meia-Idade , SARS-CoV-2/isolamento & purificação , Estudos Prospectivos , Espectroscopia de Luz Próxima ao Infravermelho , Estudos de Coortes
4.
Neurochem Res ; 49(7): 1665-1676, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38411782

RESUMO

Cerebral ischemic preconditioning (CIP) has been shown to improve brain ischemic tolerance against subsequent lethal ischemia. Reactive astrocytes play important roles in cerebral ischemia-reperfusion. Recent studies have shown that reactive astrocytes can be polarized into neurotoxic A1 phenotype (C3d) and neuroprotective A2 phenotype (S100A10). However, their role in CIP remains unclear. Here, we focused on the role of N-myc downstream-regulated gene 2 (NDRG2) in regulating the transformation of A1/A2 astrocytes and promoting to brain ischemic tolerance induced by CIP. A Sprague Dawley rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) was used. Rats were divided into the following six groups: (1) sham group; (2) CIP group: left middle cerebral artery was blocked for 10 min; (3) MCAO/R group: left middle cerebral artery was blocked for 90 min; (4) CIP + MCAO/R group: CIP was performed 72 h before MCAO/R; (5) AAV-NDRG2 + CIP + MCAO/R group: adeno-associated virus (AAV) carrying NDRG2 was administered 14 days before CIP + MCAO/R; (6) AAV-Ctrl + CIP + MCAO/R group: empty control group. The rats were subjected to neurological evaluation 24 h after the above treatments, and then were sacrificed for 2, 3, 5-triphenyltetraolium chloride staining, thionin staining, immunofluorescence and western blot analysis. In CIP + MCAO/R group, the neurological deficit scores decreased, infarct volume reduced, and neuronal density increased compared with MCAO/R group. Notably, CIP significantly increased S100A10 expression and the number of S100A10+/GFAP+ cells, and also increased NDRG2 expression. MCAO/R significantly decreased S100A10 expression and the number of S100A10+/GFAP+ cells yet increased C3d expression and the number of C3d+/GFAP+ cells and NDRG2 expression, and these trends were reversed by CIP + MCAO/R. Furthermore, over-expression of NDRG2 before CIP + MCAO/R, the C3d expression and the number of C3d+/GFAP+ cells increased, while S100A10 expression and the number of S100A10+/GFAP+ cells decreased. Meanwhile, over-expression of NDRG2 blocked the CIP-induced brain ischemic tolerance. Taken together, these results suggest that CIP exerts neuroprotective effects against ischemic injury by suppressing A1 astrocyte polarization and promoting A2 astrocyte polarization via inhibiting NDRG2 expression.


Assuntos
Astrócitos , Isquemia Encefálica , Infarto da Artéria Cerebral Média , Precondicionamento Isquêmico , Ratos Sprague-Dawley , Animais , Precondicionamento Isquêmico/métodos , Masculino , Astrócitos/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Isquemia Encefálica/metabolismo , Ratos , Proteínas do Tecido Nervoso
5.
J Neuroeng Rehabil ; 21(1): 116, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997727

RESUMO

OBJECTIVE: This study explored the impact of one session of low-pressure leg blood flow restriction (BFR) during treadmill walking on dual-task performance in older adults using the neurovisceral integration model framework. METHODS: Twenty-seven older adults participated in 20-min treadmill sessions, either with BFR (100 mmHg cuff pressure on both thighs) or without it (NBFR). Dual-task performance, measured through light-pod tapping while standing on foam, and heart rate variability during treadmill walking were compared. RESULTS: Following BFR treadmill walking, the reaction time (p = 0.002) and sway area (p = 0.012) of the posture dual-task were significantly reduced. Participants exhibited a lower mean heart rate (p < 0.001) and higher heart rate variability (p = 0.038) during BFR treadmill walking. Notably, BFR also led to band-specific reductions in regional brain activities (theta, alpha, and beta bands, p < 0.05). The topology of the EEG network in the theta and alpha bands became more star-like in the post-test after BFR treadmill walking (p < 0.005). CONCLUSION: BFR treadmill walking improves dual-task performance in older adults via vagally-mediated network integration with superior neural economy. This approach has the potential to prevent age-related falls by promoting cognitive reserves.


Assuntos
Frequência Cardíaca , Caminhada , Humanos , Idoso , Masculino , Feminino , Caminhada/fisiologia , Frequência Cardíaca/fisiologia , Teste de Esforço , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Fluxo Sanguíneo Regional/fisiologia , Desempenho Psicomotor/fisiologia , Perna (Membro)/fisiologia
6.
J Asian Nat Prod Res ; 26(10): 1247-1253, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38949198

RESUMO

One new canthinone glycoside (1), together with six known compounds (2-7) including three lignans (2-4), two coumarins (5-6) and one phenol (7) was isolated from the root barks of Ailanthus altissima. The structure of new compound 1 was established by the interpretation of UV, IR, MS and NMR data, while its absolute configuration was determined by acid hydrolysis and GIAO NMR calculations with DP4+ probability analysis. The inhibitory effects of all compounds on Nitric oxide (NO) production were investigated in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Results showed that compounds 2 and 5 displayed NO production inhibitory activity with IC50 values of 30.1 and 15.3 µM, respectively.


Assuntos
Ailanthus , Glicosídeos , Lipopolissacarídeos , Óxido Nítrico , Casca de Planta , Raízes de Plantas , Ailanthus/química , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Camundongos , Estrutura Molecular , Animais , Casca de Planta/química , Raízes de Plantas/química , Células RAW 264.7 , Glicosídeos/farmacologia , Glicosídeos/química , Glicosídeos/isolamento & purificação , Lipopolissacarídeos/farmacologia , Lignanas/farmacologia , Lignanas/química , Lignanas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Cumarínicos/farmacologia , Cumarínicos/química , Cumarínicos/isolamento & purificação , Ressonância Magnética Nuclear Biomolecular
7.
Int J Mol Sci ; 25(11)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38892437

RESUMO

Reliable and accurate methods of estimating the accuracy of predicted protein models are vital to understanding their respective utility. Discerning how the quaternary structure conforms can significantly improve our collective understanding of cell biology, systems biology, disease formation, and disease treatment. Accurately determining the quality of multimeric protein models is still computationally challenging, as the space of possible conformations is significantly larger when proteins form in complex with one another. Here, we present EGG (energy and graph-based architectures) to assess the accuracy of predicted multimeric protein models. We implemented message-passing and transformer layers to infer the overall fold and interface accuracy scores of predicted multimeric protein models. When evaluated with CASP15 targets, our methods achieved promising results against single model predictors: fourth and third place for determining the highest-quality model when estimating overall fold accuracy and overall interface accuracy, respectively, and first place for determining the top three highest quality models when estimating both overall fold accuracy and overall interface accuracy.


Assuntos
Modelos Moleculares , Redes Neurais de Computação , Proteínas , Proteínas/química , Proteínas/metabolismo , Biologia Computacional/métodos , Multimerização Proteica , Conformação Proteica
8.
Neuroimage ; 269: 119902, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36708973

RESUMO

Previous work has proposed two potential benefits of retrospective attention on working memory (WM): target strengthening and non-target inhibition. It remains unknown which hypothesis contributes to the improved WM performance, yet the neural mechanisms responsible for this attentional benefit are unclear. Here, we recorded electroencephalography (EEG) signals while 33 participants performed a retrospective-cue WM task. Multivariate pattern classification analysis revealed that only representations of target features were enhanced by valid retrospective attention during retention, supporting the target strengthening hypothesis. Further univariate analysis found that mid-frontal theta inter-trial phase coherence (ITPC) and ERP components were modulated by valid retrospective attention and correlated with individual differences and moment-to-moment fluctuations on behavioral outcomes, suggesting that both trait- and state-level variability in attentional preparatory processes influence goal-directed behavior. Furthermore, task-irrelevant target spatial location could be decoded from EEG signals, indicating that enhanced spatial binding of target representation is vital to high WM precision. Importantly, frontoparietal theta-alpha phase-amplitude coupling was increased by valid retrospective attention and predicted the reduced random guessing rates. This long-range connection supported top-down information flow in the engagement of frontoparietal networks, which might organize attentional states to integrate target features. Altogether, these results provide neurophysiological bases that retrospective attention improves WM precision by enhancing flexible target representation and emphasize the critical role of the frontoparietal attentional network in the control of WM representations.


Assuntos
Atenção , Memória de Curto Prazo , Humanos , Memória de Curto Prazo/fisiologia , Estudos Retrospectivos , Atenção/fisiologia , Eletroencefalografia , Cognição
9.
Cancer Immunol Immunother ; 72(4): 903-916, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36161509

RESUMO

Tumor-associated macrophages (TAMs) play an important role in tumor growth and metastasis. However, the involvement of TAMs infiltration in pulmonary osteosarcoma (OS) metastasis remains poorly understood. Therefore, the effect of OS cells on macrophages migration was investigated by in vivo and in vitro experiments to evaluate the infiltration and mechanism of TAMs in pulmonary OS metastases. The results showed that the zinc finger protein ZIM3 was upregulated in OS cells than in osteoblasts and activated the expression of CCL25, which subsequently promoted the migration of M2 macrophages. CCL25 or ZIM3 silencing in OS cells inhibited the infiltration of M2 macrophages and the formation of pulmonary metastatic nodules in a mouse model of pulmonary OS metastasis and prolonged the survival of the mice. Furthermore, bioinformatics analyses revealed that CCL25 and ZIM3 expressions are negatively correlated with the prognosis of OS patients. In conclusion, this study found that a large number of M2 TAMs were recruited into pulmonary metastatic nodules of OS through the activation of the ZIM3-CCL25 axis in OS cells, thereby facilitating OS metastasis. Therefore, the suppression of ZIM3-CCL25-induced recruitment of M2 TAMs to the metastatic sites might be considered as a therapeutic approach to inhibit the growth of pulmonary OS metastases.


Assuntos
Neoplasias Ósseas , Neoplasias Pulmonares , Osteossarcoma , Animais , Camundongos , Macrófagos/metabolismo , Linhagem Celular Tumoral , Prognóstico , Neoplasias Pulmonares/tratamento farmacológico , Osteossarcoma/genética , Osteossarcoma/tratamento farmacológico , Neoplasias Ósseas/genética , Microambiente Tumoral , Quimiocinas CC/metabolismo , Quimiocinas CC/farmacologia , Quimiocinas CC/uso terapêutico
10.
Cereb Cortex ; 32(22): 4953-4968, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-35076708

RESUMO

Selective attention is thought to involve target enhancement and distractor inhibition processes. Here, we recorded simultaneous electroencephalographic (EEG) and functional near-infrared spectroscopy (fNIRS) data from human adults when they were pre-cued by the visual field of coming target, distractor, or both of them. From the EEG data, we found alpha power relatively decreased contralaterally to the to-be-attended target, as reflected by the positive-going alpha modulation index. Late alpha power relatively increased contralaterally to the to-be-suppressed distractor, as reflected by the negative-going alpha modulation index. From the fNIRS data, we found enhancements of hemodynamic activity over the contralateral hemisphere in response to both the target and the distractor anticipation but within nonoverlapping posterior brain regions. More importantly, we described the specific neurovascular modulation between alpha power and oxygenated hemoglobin signal, which showed a positive coupling effect during target anticipation and a negative coupling effect during distractor anticipation. Such flexible neurovascular couplings between EEG oscillation and hemodynamic activity seem to play an essential role in the final behavioral outcomes. These results provide unique neurovascular evidence for the dissociation of the mechanisms of target enhancement and distractor inhibition. Individual behavioral differences can be related to individual differences in neurovascular coupling.


Assuntos
Acoplamento Neurovascular , Adulto , Humanos , Acoplamento Neurovascular/fisiologia , Atenção/fisiologia , Eletroencefalografia/métodos , Hemodinâmica/fisiologia , Sinais (Psicologia)
11.
Thorac Cardiovasc Surg ; 71(8): 671-679, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37186190

RESUMO

BACKGROUND: Patients undergoing lung tumor surgery may experience various complications after discharge from the hospital. Using patient-reported outcomes (PROs), this study attempted to identify relevant indicators of postdischarge complications after lung tumor surgery and develop a predictive nomogram model to evaluate the risk for individual patients. METHODS: Patients who underwent lung tumor surgery between December 2021 and June 2022 were included in this study. PROs were assessed using the Perioperative Symptom Assessment for Lung Surgery scale and were assessed preoperatively at baseline, on postoperative day 1 (POD1) 1 to POD4, and then weekly until the fourth week. A random forest machine learning prediction model was built to rank the importance of each PRO score of patients on POD1 to POD4. We then selected the top 10 variables in terms of importance for the multivariable logistic regression analysis. Finally, a nomogram was developed. RESULTS: PROs, including coughing (POD3 and POD4), daily activity (POD1), and pain (POD1 and POD2), were associated with postdischarge complications in patients undergoing lung tumor surgery. The predictive model showed good performance in estimating the risk of postdischarge complications, with an area under the curve of 0.833 (95% confidence interval: 0.753-0.912), while maintaining good calibration and clinical value. CONCLUSION: We found that PRO scores on POD1 to POD4 were associated with postdischarge complications after lung tumor surgery, and we developed a helpful nomogram model to predict the risk of postdischarge complications.


Assuntos
Neoplasias Pulmonares , Alta do Paciente , Humanos , Assistência ao Convalescente , Resultado do Tratamento , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/complicações , Pulmão , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia
12.
J Asian Nat Prod Res ; 25(4): 316-323, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35771726

RESUMO

Two new guaianolide-type sesquiterpenoids chrysanthemulides K and L (1 and 2), together with six known analogues (3-8), were isolated from an CH2Cl2 extract of the aerial parts of Chrysanthemum indicum. The structures of new compounds 1 and 2 were established by extensive spectroscopic analysis, including UV, IR, MS, NMR and computational electronic circular dichroism (ECD) methods. Inhibitory effects of all compounds on nitric oxide production were investigated in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Results showed that compounds 1-8 displayed NO production inhibitory activity with IC50 values ranged from 3.5 to 34.3 µM.


Assuntos
Chrysanthemum , Sesquiterpenos , Animais , Camundongos , Chrysanthemum/química , Células RAW 264.7 , Sesquiterpenos/química , Extratos Vegetais/farmacologia , Espectroscopia de Ressonância Magnética , Óxido Nítrico , Estrutura Molecular , Lipopolissacarídeos/farmacologia
13.
J Environ Manage ; 344: 118416, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37331315

RESUMO

Knowledge on relationship and determinants of water and carbon dioxide (CO2) exchange is crucial to land managers and policy makers especially for the desertified land restoration. However, there remains highly uncertain in terms of water use and carbon sequestration for artificial plantation in desert. Here, continuous water and carbon fluxes were measured using eddy covariance (EC) in conjunction with hydrometeorological measurements over an artificial C4 shrub, Haloxylon ammodendron (C. A. Mey.) Bunge, from July 2020 to 2021 in Tengger Desert, China. Throughout 2021, evapotranspiration (ET) was 189.5 mm, of which 85% (150 mm) occurred during growing season, that was comparable with the summation of precipitation (132.2 mm), dew (33.5 mm) and potential other sources (e.g. deep subsoil water). This ecosystem was a strong carbon sink with net ecosystem production (NEP) up to 446.4 g C m-2 yr-1, much higher than surrounding sites. Gross primary production (GPP, 598.7 g C m-2 yr-1) in this shrubland was comparable with that of other shrublands, whereas ecosystem respiration (Re, 152.3 g C m-2 yr-1) was lower. Random Forest showed that environmental factors can explain 71.56% and 80.07% variation of GPP and ET, respectively. Interestingly, environmental factors have divergent effect on water and carbon exchange, i.e., soil hydrothermic factors (soil moisture content and soil temperature) determine the magnitude and seasonal pattern of ET and Re, while aerodynamics factors (net radiation, atmospheric temperature and wind speed) determine GPP and NEP. As such, divergent response of abiotic factors resulted in the decoupling of water and carbon exchange. Our results suggest that H. ammodendron is a suitable species for large-scale afforestation in dryland given its low water use but high carbon sequestration. Therefore, we infer that artificial planting H. ammodendron in dryland could provide an opportunity for climate change mitigation, and the long-term time series data is needed to confirm its sustainable role of carbon sequestration in the future.


Assuntos
Ecossistema , Água , Ciclo do Carbono , Sequestro de Carbono , Solo , Estações do Ano , Dióxido de Carbono/análise
14.
Proteins ; 90(12): 2091-2102, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35842895

RESUMO

The estimation of protein model accuracy (EMA) or model quality assessment (QA) is important for protein structure prediction. An accurate EMA algorithm can guide the refinement of models or pick the best model or best parts of models from a pool of predicted tertiary structures. We developed two novel methods: MASS2 and LAW, for predicting residue-specific or local qualities of individual models, which incorporate residual neural networks and graph neural networks, respectively. These two methods use similar features extracted from protein models but different architectures of neural networks to predict the local accuracies of single models. MASS2 and LAW participated in the QA category of CASP14, and according to our evaluations based on CASP14 official criteria, MASS2 and LAW are the best and second-best methods based on the Z-scores of ASE/100, AUC, and ULR-1.F1. We also evaluated MASS2, LAW, and the residue-specific predicted deviations (between model and native structure) generated by AlphaFold2 on CASP14 AlphaFold2 tertiary structure (TS) models. LAW achieved comparable or better performances compared to the predicted deviations generated by AlphaFold2 on AlphaFold2 TS models, even though LAW was not trained on any AlphaFold2 TS models. Specifically, LAW performed better on AUC and ULR scores, and AlphaFold2 performed better on ASE scores. This means that AlphaFold2 is better at predicting deviations, but LAW is better at classifying accurate and inaccurate residues and detecting unreliable local regions. MASS2 and LAW can be freely accessed from http://dna.cs.miami.edu/MASS2-CASP14/ and http://dna.cs.miami.edu/LAW-CASP14/, respectively.


Assuntos
Biologia Computacional , Proteínas , Biologia Computacional/métodos , Modelos Moleculares , Proteínas/química , Redes Neurais de Computação , Algoritmos , Conformação Proteica
15.
Mol Genet Genomics ; 296(2): 279-287, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33245431

RESUMO

NAC (NAM, AFAT1/2, and CUC2) transcription factors play important roles in plant growth and in resistance to abiotic and biotic stresses. Here, we show that the TaNAC35 gene negatively regulates leaf rust resistance in the wheat line Thatcher + Lr14b (TcLr14b) when challenged with a virulent isolate of Puccinia triticina (Pt). The TaNAC35 gene was cloned from this line, and blastp results showed that its open reading frame (ORF) was 96.16% identical to the NAC35-like sequence reported from Aegilops tauschii, and that it encoded a protein with 387 amino acids (aa) including a conserved NAM domain with 145 aa at the N-terminal alongside the transcriptional activation domain with 220 aa in the C-terminal. Yeast-one-hybrid analysis proved that the C-terminal of the TaNAC35 protein was responsible for transcriptional activation. A 250-bp fragment from the 3'-end of this target gene was introduced to a BSMV-VIGS vector and used to infect the wheat line Thatcher + Lr14b (TcLr14b). The BSMV-VIGS/TaNAC35-infected plant material showed enhanced resistance (infection type "1") to Pt pathotype THTT, which was fully virulent (infection type "4") on BSMV-VIGS only infected TcLr14b plants. Histological studies showed that inhibition of TaNAC35 reduced the formation of haustorial mother cells (HMC) and mycelial growth, implying that the TaNAC35 gene plays a negative role in the response of TcLr14b to Pt pathotype THTT. These results provide molecular insight into the interaction between Pt and its wheat host, and identify a potential target for engineering resistance in wheat to this damaging pathogen.


Assuntos
Resistência à Doença , Puccinia/patogenicidade , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Triticum/microbiologia , Sequência de Aminoácidos , Clonagem Molecular , Interações Hospedeiro-Patógeno , Filogenia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Folhas de Planta/microbiologia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Domínios Proteicos , Fatores de Transcrição/química , Ativação Transcricional , Triticum/genética
16.
J Nanobiotechnology ; 19(1): 216, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34281552

RESUMO

Sepsis, the syndrome of infection complicated by acute organ dysfunction, is a serious and growing global problem, which not only leads to enormous economic losses but also becomes one of the leading causes of mortality in the intensive care unit. The detection of sepsis-related pathogens and biomarkers in the early stage plays a critical role in selecting appropriate antibiotics or other drugs, thereby preventing the emergence of dangerous phases and saving human lives. There are numerous demerits in conventional detection strategies, such as high cost, low efficiency, as well as lacking of sensitivity and selectivity. Recently, the aptamer-based biosensor is an emerging strategy for reasonable sepsis diagnosis because of its accessibility, rapidity, and stability. In this review, we first introduce the screening of suitable aptamer. Further, recent advances of aptamer-based biosensors in the detection of bacteria and biomarkers for the diagnosis of sepsis are summarized. Finally, the review proposes a brief forecast of challenges and future directions with highly promising aptamer-based biosensors.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Sepse/diagnóstico , Aptâmeros de Nucleotídeos , Bactérias , Biomarcadores , Citocinas , Humanos
17.
Pharmacology ; 106(9-10): 551-563, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34175854

RESUMO

BACKGROUND: Oral squamous cell carcinoma (OSCC) is among the most prevalent head and neck malignancies globally, and it is associated with high mortality rates. Actein is one of the primary active components extractable from the rhizomes of Cimicifuga foetida. This study aimed to evaluate the anti-OSCC effects of actein and evaluate the potential underlying mechanisms. METHODS AND RESULTS: CCK-8 cell proliferation experiments demonstrated significant dose- and time-dependent anti-OSCC effects of actein, while actein had weak cytotoxic effects on normal oral cell lines. Flow cytometry for cell cycle evaluation revealed that actein could induce cell cycle arrest at the G1 phase among OSCC cell lines. In our Annexin V/PI double staining apoptosis analysis, actein induced significant apoptosis among OSCC cells, with upregulation of Bax and downregulation of Bcl-2. Our mechanistic study implicated the involvement of the Akt/FoxO1 pathway in the anti-OSCC effects of actein. Akt1 and Akt2 expression significantly decreased in association with the FoxO1 upregulation. Furthermore, Bim and p21 were significantly upregulated, while survivin expression was downregulated. Finally, actein treatment was associated with significant p-Akt downregulation and p-FoxO1 upregulation in OSCC cells, demonstrating the validated roles of Akt/FoxO1 in actein-mediated OSCC cell apoptosis and cell cycle arrest. FoxO1 knockdown significantly reversed the anti-OSCC effects of actein. Additionally, a xenograft model indicated that actein could inhibit OSCC cell growth in vivo. CONCLUSIONS: Our findings demonstrated that actein could be a strong anti-OSCC candidate. Further evaluations of its safety and effectiveness are necessary before it can be considered for clinical use.


Assuntos
Carcinoma de Células Escamosas/patologia , Medicamentos de Ervas Chinesas/farmacologia , Proteína Forkhead Box O1/efeitos dos fármacos , Neoplasias Bucais/patologia , Saponinas/farmacologia , Triterpenos/farmacologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo , Feminino , Genes bcl-2/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Tempo , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína X Associada a bcl-2/efeitos dos fármacos
18.
J Asian Nat Prod Res ; 23(9): 877-883, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32603195

RESUMO

ABSTACTA chemical investigation of the whole plant of traditional Chinese medicine, Chrysanthemum indicum L., led to the discovery of six guaianolide-type sesquiterpenoids 1-6 with a 1,10-splited skeleton. The structure of the new compound 1 was established by extensive analysis of UV, IR, MS, NMR and ECD data. Compounds 3-6 are mutually stereoisomers with four chiral centers and their absolute configurations were determined by comparison of ECD spectra. The anti-inflammatory effects of these isolates on lipopolysaccharide (LPS)-induced nitric oxide (NO) were investigated in RAW 264.7 cells. Results showed that most of the compounds displayed NO production inhibitory activities with IC50 values ranged from 3.54 to 8.17 µM.


Assuntos
Chrysanthemum , Sesquiterpenos , Animais , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , Óxido Nítrico , Células RAW 264.7 , Sesquiterpenos/farmacologia
19.
BMC Oral Health ; 21(1): 232, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33941139

RESUMO

BACKGROUND: Oral squamous cell carcinoma (OSCC) is one of the most common maligancies of the head and neck. The prognosis was is significantly different among OSCC patients. This study aims to identify new biomarkers to establish a prognostic model to predict the survival of OSCC patients. METHODS: The mRNA expression and corresponding clinical information of OSCC patients were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus. Additionally, a total of 26 hypoxia-related genes were also obtained from a previous study. Univariate Cox regression analysis and LASSO Cox regression analysis were performed to screen the optimal hypoxia-related genes which were associated with the prognosis of OSCC. to establish the predictive model (Risk Score) was established for estimating the patient's overall survival (OS). Multivariate Cox regression analysis was used to determine whether the Risk Score was an independent prognostic factor. Based on all the independent prognostic factors, nomogram was established to predict the OS probability of OSCC patients. The relative proportion of 22 immune cell types in each patient was evaluated by CIBERSORT software. RESULTS: We determined that a total of four hypoxia-related genes including ALDOA, P4HA1, PGK1 and VEGFA were significantly associated with the prognosis of OSCC patients. The nomogram established based on all the independent factors could reliably predict the long-term OS of OSCC patients. In addition, our resluts indicated that the inferior prognosis of OSCC patients with high Risk Score might be related to the immunosuppressive microenvironments. CONCLUSION: This study shows that high expression of hypoxia-related genes including ALDOA, P4HA1, PGK1 and VEGFA is associated with poor prognosis in OSCC patients, and they can be used as potential markers for predicting prognosis in OSCC patients.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Carcinoma de Células Escamosas/genética , Humanos , Hipóxia/genética , Neoplasias Bucais/genética , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço , Microambiente Tumoral
20.
Am J Respir Cell Mol Biol ; 63(1): 46-56, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32176858

RESUMO

Goblet cell metaplasia, excessive mucus production, and inadequate mucus clearance accompany and exacerbate multiple chronic respiratory disorders, such as asthma and chronic obstructive pulmonary disease. Notch signaling plays a central role in controlling the fate of multiple cell types in the lung, including goblet cells. In the present study, we explored the therapeutic potential of modulating the Notch pathway in the adult murine lung using chemically modified antisense oligonucleotides (ASOs). To this end, we designed and characterized ASOs targeting the Notch receptors Notch1, Notch2, and Notch3 and the Notch ligands Jag1 (Jagged 1) and Jag2 (Jagged 2). Pulmonary delivery of ASOs in healthy mice or mice exposed to house dust mite, a commonly used mouse model of asthma, resulted in a significant reduction of the respective mRNAs in the lung. Furthermore, ASO-mediated knockdown of Jag1 or Notch2 in the lungs of healthy adult mice led to the downregulation of the club cell marker Scgb1a1 and the concomitant upregulation of the ciliated cell marker FoxJ1 (forkhead box J1). Similarly, ASO-mediated knockdown of Jag1 or Notch2 in the house dust mite disease model led to reduced goblet cell metaplasia and decreased mucus production. Because goblet cell metaplasia and excessive mucus secretion are a common basis for many lung pathologies, we propose that ASO-mediated inhibition of JAG1 could provide a novel therapeutic path for the treatment of multiple chronic respiratory diseases.


Assuntos
Células Caliciformes/efeitos dos fármacos , Células Caliciformes/metabolismo , Proteína Jagged-1/metabolismo , Pulmão/efeitos dos fármacos , Metaplasia/tratamento farmacológico , Metaplasia/metabolismo , Oligonucleotídeos Antissenso/farmacologia , Animais , Asma/metabolismo , Biomarcadores/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Fatores de Transcrição Forkhead/metabolismo , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pyroglyphidae , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
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