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In order to achieve the high adsorption and catalytic performance of CO2, the direct self-assembly of robust defect-engineered MOFs is a scarcely reported and challenging proposition. Herein, a highly robust nanoporous indium(III)-organic framework of {[In2(CPPDA)(H2O)3](NO3)·2DMF·3H2O}n (NUC-107) consisting of two kinds of inorganic units of chain-shaped [In(COO)2(H2O)]n and watery binuclear [In2(COO)4(H2O)8] was generated by regulating the growth environment. It is worth mentioning that [In2(COO)4(H2O)8] is very rare in terms of its richer associated water molecules, implying that defect-enriched metal ions in the activated host framework can serve as strong Lewis acid. Compared to reported skeleton of [In4(CPPDA)2(µ3-OH)2(DMF)(H2O)2]n (NUC-66) with tetranuclear clusters of [In4(µ3-OH)2(COO)10(DMF)(H2O)2] as nodes, the void volume of NUC-107 (50.7%) is slightly lower than the one of NUC-66 (52.8%). However, each In3+ ion in NUC-107 has an average of 1.5 coordinated small molecules (H2O), which far exceeds the average of 0.75 in NUC-66 (H2O and DMF). After thermal activation, NUC-107a characterizes the merits of unsaturated In3+ sites, free pyridine moieties, solvent-free nanochannels (10.2 × 15.7 Å2). Adsorption tests prove that the host framework of NUC-107a has a higher CO2 adsorption (113.2 cm3/g at 273 K and 64.8 cm3/g at 298 K) than NUC-66 (91.2 cm3/g at 273 K and 53.0 cm3/g at 298 K). Catalytic experiments confirmed that activated NUC-107a with the aid of n-Bu4NBr was capable of efficiently catalyzing the cycloaddition of CO2 with epoxides into corresponding cyclic carbonates under the mild conditions. Under the similar conditions of 0.10 mol% MOFs, 0.5 mol% n-Bu4NBr, 0.5 MP CO2, 60 °C and 3 h, compared with NUC-66a, the conversion of SO to SC catalyzed by NUC-107a increased by 21%. Hence, this work offers a valuable perspective that the in situ creation of robust defect-engineered MOFs can be realized by regulating the growth environment.
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Developing a highly active catalyst that can efficiently capture and convert carbon dioxide (CO2) into high-value-added energy materials remains a severe challenge, which inspires us to explore effective metal-organic frameworks (MOFs) with high chemical stability and high-density active sites. Herein, we report a robust 3D lead(II)-organic framework of {(Me2NH2)2[Pb5(PTTPA)2(H2O)3]·2DMF·3H2O}n (NUC-111) with unreported [Pb10(COO)22(H2O)6] clusters (abbreviated as {Pb10}) as nodes (H6PTTPA = 4,4',4â³-(pyridine-2,4,6-triyl)triisophthalic acid). After thermal activation, NUC-111a is functionalized by the multifarious symbiotic acid-base active sites of open Pb2+ sites and uncoordinated pyridine groups on the inner surface of the void volume. Gas adsorption tests confirm that NUC-111a displays a higher separation performance for mixed gases of f CO2 and CH4 with the selectivity of CO2/CH4 at 273 K and 101 kPa being 31 (1:99, v/v), 23 (15:85, v/v), and 8 (50:50, v/v), respectively. When the temperature rises to 298 K, the selectivity of CO2/CH4 at 101 kPa is 26 (1:99, v/v), 22 (15:85, v/v), and 11 (50:50, v/v). Moreover, activated NUC-111a exhibited excellent catalytic performance, stability, and recyclability for the cycloaddition of CO2 with epoxides under mild conditions. Hence, this work provides valuable insight into designing MOFs with multifunctionality for CO2 capture, separation, and conversion.
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A series of bis(indolyl)-hydrazide-hydrazone derivatives were synthesised, and their structures were characterised using 1H-NMR and HRMS. The antifungal activity of the prepared compounds was evaluated against Pyricularia oryzae Cav., Colletotrichum -gloeosporioides Penz., Botrytis cinerea Pers.: Fr. and Rhizoctonia solani Kühn using the mycelial growth rate method. The preliminary bioassays revealed that most of the synthesised compounds exhibited antifungal activity against the four tested fungi and displayed a remarkable inhibitory effect on the mycelium growth of R. solani. In particular, compounds 3b, 3c, and 3k demonstrated significant antifungal activity against R. solani, with EC50 values of 26.42, 20.74, and 22.41 µM, respectively, outperforming the positive control shenqinmycin (47.18 µM) and carvacrol (49.13 µM).
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The rapid detection of epinephrine (EPI) in serum holds immense importance in the early disease diagnosis and regular monitoring. On the basis of the coordination post-synthetic modification (PSM) strategy, a Eu3+ functionalized ZnMOF (Eu3+@ZnMOF) was fabricated by anchoring the Eu3+ ions within the microchannels of ZnMOF as secondary luminescent centers. Benefiting from two independent luminescent centers, the prepared Eu3+@ZnMOF shows great potential as a multi-signal self-calibrating luminescent sensor in visually and efficiently detecting serum EPI levels, with high reliability, fast response time, excellentrecycleability, and low detection limits of 17.8 ng/mL. Additionally, an intelligent sensing system was designed in accurately and reliably detecting serum EPI levels, based on the designed self-calibrating logic gates. Furthermore, the possible sensing mechanisms were elucidated through theoretical calculations as well as spectral overlaps. This work provides an effective and promising strategy for developing MOFs-based self-calibrating intelligent sensing platforms to detect bioactive molecules in bodily fluids.
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Epinefrina , Európio , Epinefrina/análise , Epinefrina/sangue , Európio/química , Limite de Detecção , Humanos , Calibragem , Medições Luminescentes/métodos , Espectrometria de Fluorescência , LógicaRESUMO
This case report presents a detailed analysis of a 31-year-old male patient who presented with a complex array of clinical symptoms, including proteinuria, hematuria, edema, and kidney insufficiency. Despite undergoing multiple tests, the results for anti-glomerular basement membrane antibodies yielded negative findings. Subsequently, kidney biopsy pathology revealed a distinct diagnosis of atypical anti-glomerular basement membrane (anti-GBM) disease with membrane hyperplasia. Treatment was initiated with a comprehensive approach involving high doses of corticosteroids therapy and cyclophosphamide (CTX). However, contrary to expectations, the patient's kidney function exhibited rapid deterioration following this therapeutic regimen. The culmination of these complications necessitated a pivotal transition to maintenance hemodialysis. This case underscores the intricate challenges associated with diagnosing and managing rare and atypical presentations of kidney disorders. The negative anti-GBM antibody results and subsequent identification of atypical anti-GBM nephropathy highlight the need for tailored diagnostic strategies to discern subtle nuances within complex clinical scenarios. Additionally, the unexpected response to the treatment regimen emphasizes the potential variability in individual patient responses, underlining the necessity for vigilant monitoring and adaptable treatment strategies. This case report contributes to the evolving understanding of atypical kidney pathologies and the complexities involved in their management.
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Doença Antimembrana Basal Glomerular , Masculino , Humanos , Adulto , Doença Antimembrana Basal Glomerular/complicações , Doença Antimembrana Basal Glomerular/diagnóstico , Doença Antimembrana Basal Glomerular/terapia , Hiperplasia/patologia , Rim/patologia , Autoanticorpos , Proteinúria/etiologia , Proteinúria/complicações , Ciclofosfamida/uso terapêuticoRESUMO
Intrinsic neural activities are characterized as endless spontaneous fluctuation over multiple time scales. However, how the intrinsic brain organization changes over time under local perturbation remains an open question. By means of statistical physics, we proposed an approach to capture whole-brain dynamics based on estimating time-varying nonreversibility and k-means clustering of dynamic varying nonreversibility patterns. We first used synthetic fMRI to investigate the effects of window parameters on the temporal variability of varying nonreversibility. Second, using real test-retest fMRI data, we examined the reproducibility, reliability, biological, and physiological correlation of the varying nonreversibility substates. Finally, using repetitive transcranial magnetic stimulation-fMRI data, we investigated the modulation effects of repetitive transcranial magnetic stimulation on varying nonreversibility substate dynamics. The results show that: (i) as window length increased, the varying nonreversibility variance decreased, while the sliding step almost did not alter it; (ii) the global high varying nonreversibility states and low varying nonreversibility states were reproducible across multiple datasets and different window lengths; and (iii) there were increased low varying nonreversibility states and decreased high varying nonreversibility states when the left frontal lobe was stimulated, but not the occipital lobe. Taken together, these results provide a thermodynamic equilibrium perspective of intrinsic brain organization and reorganization under local perturbation.
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Mapeamento Encefálico , Encéfalo , Reprodutibilidade dos Testes , Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Estimulação Magnética Transcraniana/métodos , Lobo FrontalRESUMO
We investigate the "roughness" of the energy landscape of a system that diffuses in a heterogeneous medium with a random position-dependent friction coefficient α(x). This random friction acting on the system stems from spatial inhomogeneity in the surrounding medium and is modeled using the generalized Caldira-Leggett model. For a weakly disordered medium exhibiting a Gaussian random diffusivity D(x) = kBT/α(x) characterized by its average value ⟨D(x)⟩ and a pair-correlation function ⟨D(x1)D(x2)⟩, we find that the renormalized intrinsic diffusion coefficient is lower than the average one due to the fluctuations in diffusivity. The induced weak internal friction leads to increased roughness in the energy landscape. When applying this idea to diffusive motion in liquid water, the dissociation energy for a hydrogen bond gradually approaches experimental findings as fluctuation parameters increase. Conversely, for a strongly disordered medium (i.e., ultrafast-folding proteins), the energy landscape ranges from a few to a few kcal/mol, depending on the strength of the disorder. By fitting protein folding dynamics to the escape process from a metastable potential, the decreased escape rate conceptualizes the role of strong internal friction. Studying the energy landscape in complex systems is helpful because it has implications for the dynamics of biological, soft, and active matter systems.
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A palladium-catalyzed allylation of hydrazines with allyl alcohols and aldehydes was developed, enabling the syntheses of a series of allylhydrazones in good to excellent yields with high regioselectivity. Furthermore, the four-component tandem allylation carbonylation of hydrazines with allyl alcohols and aldehydes was established using the catalytic system, producing various allyl acylhydrazones. Additionally, the functionalized allyl acylhydrazones could be smoothly constructed with the catalytic system employing allylhydrazones as a partner. The catalytic system exhibited good functional tolerance with excellent regioselectivities and scaled-up capability, overcoming the limitations of chemoselectivity of the multicomponent transformation and poor conversion of the weak nucleophile.
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Enhancing the catalysis of metal-organic frameworks (MOFs) by regulating inherent Lewis acid-base sites to realize the efficient seperation and chemical fixation of inert carbon dioxide (CO2) is crucial but challenging. Herein, the solvothermal self-assembly of Co2+, 5'-(4-carboxy-2-nitrophenyl)-2,2',2'',4',6'-pentanitro-[1,1':3',1''-terphenyl]-4,4''-dicarboxylic acid (H3TNBTB) and 4'-phenyl-4,2':6',4''-terpyridine (PTP) generated a highly robust cobalt-organic framework of {[Co3(TNBTB)2(PTP)]·7DMF·6H2O}n (NUC-82). In NUC-82, the tri-core clusters of {Co3} with linear shape are bridged by TNBTB3- to form two-dimensional structure in ac plane, which is further linked by PTP to generate a three-dimensional framework with two kinds of solvent-accessible channels: rhombic-like (ca. 11.57 × 10.76 Å) along a axis and rectangular-like (ca. 7.32 × 11.56 Å) along b axis. Furthermore, it is worth emphasizing that the confined pore environments are characterized by plentiful Lewis acid-base sites of tricobalt clusters, grafted nitro groups and free pyridinyl, high specific surface area and solvent-free nano-caged windows. Activated NUC-82a owns the ultra-high ethylene (C2H2) separation performance over the mixture of C2H2/CH4 and CO2/CH4 with the selectivity of 223.1 and 44.7. Thanks to the great Lewis-acid sites as well as the large pore volume, activated NUC-82a displays the high catalytic performace on the cycloaddition of CO2 with epoxides under wield condtions such as amibient pressure. Furthermore, because of the rich Lewis base sites, NUC-82a can efficiently catalyze Knoevenagel condensation of aldehydes and malononitrile. In the above organic reactions, NUC-82a not only shows the high catalytic activity, but also exhibits the high selectivity, satifactory recyclability and easy-to-separate heterogeneity, confirming that NUC-82a is a promising catalyst. Hence, this work provides in-depth insight into the construction of multifunctional MOFs by modifying the traditional ligands with as many Lewis acid-base active sites as possible.
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To detect the effects of long non-coding ribonucleic acid (lncRNA) actin filament-associated protein 1-antisense RNA1 (AFAP1-AS1) on the proliferation and apoptosis of non-small cell lung cancer (NSCLC) A549 cells and its mechanism. 1) The expression of lncRNA AFAP1-AS1 in NSCLC A549 cells was detected via quantitative reverse transcription-polymerase chain reaction (qRT-PCR). 2) The changes in proliferation and apoptosis of A549 cells after low expression of lncRNA AFAP1-AS1 were detected using cell counting kit-8 (CCK-8) and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assays. 3) The changes in Wnt signaling pathway proteins in A549 cells after low expression of lncRNA AFAP1-AS1 were detected using Western blotting. 1) The expression of lncRNA AFAP1-AS1 rose in A549 cells (P<0.01). 2) After low expression of lncRNA AFAP1-AS1, the growth of A549 cells was inhibited, and apoptosis was promoted. 3) After low expression of lncRNA AFAP1-AS1, the mRNA and protein expressions of glycogen synthase kinase (GSK) and ß-catenin declined (P<0.05). Lowly-expressed AFAP1-AS1 inhibits the proliferation and promotes the apoptosis of NSCLC A549 cells via inhibiting the Wnt signaling pathway.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , RNA Longo não Codificante , Via de Sinalização Wnt , Humanos , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Via de Sinalização Wnt/genéticaRESUMO
BACKGROUND: Heterogeneity among critically ill patients undergoing invasive mechanical ventilation (IMV) treatment could result in high mortality rates. Currently, there are no well-established indicators to help identify patients with a poor prognosis in advance, which limits physicians' ability to provide personalized treatment. This study aimed to investigate the association of oxygen saturation index (OSI) trajectory phenotypes with intensive care unit (ICU) mortality and ventilation-free days (VFDs) from a dynamic and longitudinal perspective. METHODS: A group-based trajectory model was used to identify the OSI-trajectory phenotypes. Associations between the OSI-trajectory phenotypes and ICU mortality were analyzed using doubly robust analyses. Then, a predictive model was constructed to distinguish patients with poor prognosis phenotypes. RESULTS: Four OSI-trajectory phenotypes were identified in 3378 patients: low-level stable, ascending, descending, and high-level stable. Patients with the high-level stable phenotype had the highest mortality and fewest VFDs. The doubly robust estimation, after adjusting for unbalanced covariates in a model using the XGBoost method for generating propensity scores, revealed that both high-level stable and ascending phenotypes were associated with higher mortality rates (odds ratio [OR]: 1.422, 95% confidence interval [CI] 1.246-1.623; OR: 1.097, 95% CI 1.027-1.172, respectively), while the descending phenotype showed similar ICU mortality rates to the low-level stable phenotype (odds ratio [OR] 0.986, 95% confidence interval [CI] 0.940-1.035). The predictive model could help identify patients with ascending or high-level stable phenotypes at an early stage (area under the curve [AUC] in the training dataset: 0.851 [0.827-0.875]; AUC in the validation dataset: 0.743 [0.709-0.777]). CONCLUSIONS: Dynamic OSI-trajectory phenotypes were closely related to the mortality of ICU patients requiring IMV treatment and might be a useful prognostic indicator in critically ill patients.
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Developing efficient and sensitive MOF-based luminescence sensors for bioactive molecule detection is of great significance and remains a challenge. Benefiting from favorable chemical and thermal stability, as well as excellent luminescence performance, a porous Zn(II)Ho(III) heterometallic-organic framework (ZnHoMOF) was selected here as a bifunctional luminescence sensor for the early diagnosis of a toluene exposure biomarker of hippuric acid (HA) through "turn-on" luminescence enhancing response and the daily monitoring of NFT/NFZ antibiotics through "turn-off" quenching effects in aqueous media with high sensitivity, acceptable selectivity, good anti-interference, exceptional recyclability performance, and low detection limits (LODs) of 0.7 ppm for HA, 0.04 ppm for NFT, and 0.05 ppm for NFZ. Moreover, the developed sensor was employed to quantify HA in diluted urine samples and NFT/NFZ in natural river water with satisfactory results. In addition, the sensing mechanisms of ZnHoMOF as a dual-response chemosensor in efficient detection of HA and NFT/NFZ antibiotics were conducted from the view of photo-induced electron transfer (PET), as well as inner filter effects (IFEs), with the help of time-dependent density functional theory (TD-DFT) and spectral overlap experiments.
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Antibacterianos , Nitrofuranos , Luminescência , BiomarcadoresRESUMO
To investigate the effect and mechanism of polydatin on bleomycin (BLM)-induced pulmonary fibrosis in a mouse model. The lung fibrosis model was induced by BLM. The contents of TNF-α, LPS, IL-6 and IL-1ß in lung tissue, intestine and serum were detected by ELISA. Gut microbiota diversity was detected by 16S rDNA sequencing; R language was used to analyse species composition, α-diversity, ß-diversity, species differences and marker species. Mice were fed drinking water mixed with four antibiotics (ampicillin, neomycin, metronidazole, vancomycin; antibiotics, ABx) to build a mouse model of ABx-induced bacterial depletion; and faecal microbiota from different groups were transplanted into BLM-treated or untreated ABx mice. The histopathological changes and collagen I and α-SMA expression were determined. Polydatin effectively reduced the degree of fibrosis in a BLM-induced pulmonary fibrosis mouse model; BLM and/or polydatin affected the abundance of the dominant gut microbiota in mice. Moreover, faecal microbiota transplantation (FMT) from polydatin-treated BLM mice effectively alleviated lung fibrosis in BLM-treated ABx mice compared with FMT from BLM mice. Polydatin can reduce fibrosis and inflammation in a BLM-induced mouse pulmonary fibrosis model. The alteration of gut microbiota by polydatin may be involved in the therapeutic effect.
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Microbioma Gastrointestinal , Fibrose Pulmonar , Camundongos , Animais , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/terapia , Fibrose Pulmonar/metabolismo , Bleomicina/farmacologia , Pulmão/patologia , Fibrose , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Camundongos Endogâmicos C57BLRESUMO
Overexpression of tumor necrosis factor-α (TNF-α) is implicated in many inflammatory diseases, including septic shock, hepatitis, asthma, insulin resistance and autoimmune diseases, such as rheumatoid arthritis and Crohn's disease. The TNF-α signaling pathway is a valuable target, and anti-TNF-α drugs are successfully used to treat autoimmune and inflammatory diseases. Here, we study anti-inflammatory activity of an anti-TNF-α peptide (SN1-13, DEFHLELHLYQSW). In the cellular level assessment, SN1-13 inhibited TNF-α-induced cytotoxicity and blocks TNF-α-triggered signaling activities (IC50 = 15.40 µM). Moreover, the potential binding model between SN1-13 and TNF-α/TNFRs conducted through molecular docking revealed that SN1-13 could stunt TNF-α mediated signaling thought blocking TNF-α and its receptor TNFR1 and TNFR2. These results suggest that SN1-13 would be a potential lead peptide to treat TNF-α-mediated inflammatory diseases.
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NF-kappa B , Fator de Necrose Tumoral alfa , Humanos , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Simulação de Acoplamento Molecular , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Inflamação/tratamento farmacológico , Peptídeos/farmacologia , Peptídeos/uso terapêuticoRESUMO
Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive approach to modulate brain activity and behavior in humans. Still, how individual resting-state brain dynamics after rTMS evolves across different functional configurations is rarely studied. Here, using resting state fMRI data from healthy subjects, we aimed to examine the effects of rTMS to individual large-scale brain dynamics. Using Topological Data Analysis based Mapper approach, we construct the precise dynamic mapping (PDM) for each participant. To reveal the relationship between PDM and canonical functional representation of the resting brain, we annotated the graph using relative activation proportion of a set of large-scale resting-state networks (RSNs) and assigned the single brain volume to corresponding RSN-dominant or a hub state (not any RSN was dominant). Our results show that (i) low-frequency rTMS could induce changed temporal evolution of brain states; (ii) rTMS didn't alter the hub-periphery configurations underlined resting-state brain dynamics; and (iii) the rTMS effects on brain dynamics differ across the left frontal and occipital lobe. In conclusion, low-frequency rTMS significantly alters the individual temporo-spatial dynamics, and our finding further suggested a potential target-dependent alteration of brain dynamics. This work provides a new perspective to comprehend the heterogeneous effect of rTMS.
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Encéfalo , Estimulação Magnética Transcraniana , Humanos , Estimulação Magnética Transcraniana/métodos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Lobo Occipital , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologiaRESUMO
Inspired by the regulatory luminescence properties of HBT derivatives, in this work, we mainly conduct a detailed theoretical exploration on the photoinduced excitation behavior of a novel di-proton-transfer type HBT derivative 1-bis(benzothiazolyl)naphthalene-diol (1-BBTND). The intramolecular double hydrogen bonding interaction and the excited state intramolecular double proton transfer (ESDPT) behavior of 1-BBTND fluorophore are investigated in combination with different polar solvent environments. From the structural changes and charge recombination induced by photoexcitation, we can conclude that strong polar solvent environment promotes the excited state dynamical reaction for 1-BBTND compound. By constructing potential energy surfaces (PESs) in S0 and S1 states, we clarify that 1-BBTND fluorophore should undergo a stepwise ESDPT reaction after photoexcitation. Combined with the size of potential energy barriers along with reaction paths in different solvents, we finally propose a new solvent-polarity-dependent stepwise ESDPT for 1-BBTND fluorophore.
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Introduction: Auditory stimulation is one of the most important influence factors in the cognitive process. It is an important guiding role in cognitive motor process. However, previous studies on auditory stimuli mainly focused on the cognitive effects of auditory stimuli on the cortex, while the role of auditory stimuli in motor imagery tasks is still unclear. Methods: In order to explore the role of auditory stimuli in motor imagery tasks, we studied the EEG power spectrum distribution characteristics, frontal parietal mismatch negative (MMN) wave characteristics, and the Inter trial phase locking consistency (ITPC) characteristics of the prefrontal cognitive cortex and parietal motor cortex. In this study, 18 subjects were hired to complete the motor imagery tasks, induced by auditory stimuli of task related verbs and task independent nouns. Results: EEG power spectrum analysis showed that the activity of the contralateral motor cortex was significantly increased under the stimulation of verbs, and the amplitude of mismatch negative wave was also significantly increased. ITPC is mainly concentrated in µ, α, and γ bands in the process of motor imagery task guided by the auditory stimulus of verbs, while it is mainly concentrated in the ß band under the nouns stimulation. This difference may be due to the impact of auditory cognitive process on motor imagery. Discussion: We speculate that there may be a more complex mechanism for the effect of auditory stimulation on the inter test phase lock consistency. When the stimulus sound has the corresponding meaning to the motor action, the parietal motor cortex may be more affected by the cognitive prefrontal cortex, thus changing its normal response mode. This mode change is due to the joint action of motor imagination, cognitive and auditory stimuli. This study provides new insight into the neural mechanism of motor imagery task guided by auditory stimuli, and provides more information on the activity characteristics of the brain network in motor imagery task by cognitive auditory stimulation.
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Transcranial alternating current stimulation (tACS) is considered to have a positive effect on the rehabilitation of Alzheimer's disease (AD) as an intervention method that matches stimulation frequency to neurogenesis frequency. However, when tACS intervention is delivered to a single target, the current received by brain regions outside the target may be insufficient to trigger neural activity, compromising the effectiveness of stimulation. Therefore, it is worth studying how single-target tACS restores gamma-band activity in the whole hippocampal-prefrontal circuit during rehabilitation. We used Sim4Life software to conduct finite element methods (FEM) on the stimulation parameters to ensure that tACS intervened only in the right hippocampus (rHPC) and did not activate the left hippocampus (lHPC) or prefrontal cortex (PFC). We stimulated the rHPC by tACS for 21 days to improve the memory function of AD mice. We simultaneously recorded local field potentials (LFPs) in the rHP, lHPC and PFC and evaluated the neural rehabilitative effect of tACS stimulation with power spectral density (PSD), cross-frequency coupling (CFC) and Granger causality. Compared to the untreated group, the tACS group exhibited an increase in the Granger causality connection and CFC between the rHPC and PFC, a decrease in those between the lHPC and PFC, and enhanced performance on the Y-maze test. These results suggest that tACS may serve as a noninvasive method for Alzheimer's disease rehabilitation by ameliorating abnormal gamma oscillation in the hippocampal-prefrontal circuit.
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Doença de Alzheimer , Estimulação Transcraniana por Corrente Contínua , Animais , Camundongos , Estimulação Transcraniana por Corrente Contínua/métodos , Memória , Lobo Temporal , Córtex Pré-FrontalRESUMO
The abuse of antibiotics and lack of new antibacterial drugs has led to the emergence of superbugs that raise fears of untreatable infections. The Cathelicidin family of antimicrobial peptide (AMP) with varying antibacterial activities and safety is considered to be a promising alternative to conventional antibiotics. In this study, we investigated a novel Cathelicidin peptide named Hydrostatin-AMP2 from the sea snake Hydrophis cyanocinctus. The peptide was identified based on gene functional annotation of the H. cyanocinctus genome and bioinformatic prediction. Hydrostatin-AMP2 showed excellent antimicrobial activity against both Gram-positive and Gram-negative bacteria, including standard and clinical Ampicillin-resistant strains. The results of the bacterial killing kinetic assay demonstrated that Hydrostatin-AMP2 had faster antimicrobial action than Ampicillin. Meanwhile, Hydrostatin-AMP2 exhibited significant anti-biofilm activity including inhibition and eradication. It also showed a low propensity to induce resistance as well as low cytotoxicity and hemolytic activity. Notably, Hydrostatin-AMP2 apparently decreased the production of pro-inflammatory cytokines in the LPS-induced RAW264.7 cell model. To sum up, these findings indicate that Hydrostatin-AMP2 is a potential peptide candidate for the development of new-generation antimicrobial drugs fighting against antibiotic-resistant bacterial infections.
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Anti-Infecciosos , Hydrophiidae , Animais , Catelicidinas/química , Antibacterianos/farmacologia , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Bactérias , Ampicilina , Testes de Sensibilidade MicrobianaRESUMO
By taking advantages of confinement effect can effectively prevent dye aggregation caused luminescent quenching, Eosin Y (EY) was encapsulated into a chemorobust porous CoMOF as secondary fluorescent signal to construct the dual-emitting sensor of EY@CoMOF. And the photo-induced electron transfer from CoMOF to EY molecules induced EY@CoMOF presenting a weak blue emission at 421 nm and a strong yellow emission at 565 nm. Those dual-emission features also endow EY@CoMOF itself great potentials as a self-calibrating ratiometric sensor in visually and efficiently monitoring hippuric acid (HA) in urine, with fast response, high sensitivity and selectivity, excellent recyclable, and low LOD (0.24 µg/mL). Furthermore, based on a tandem combinational logic gate, an intelligent detection system was designed to improve the practicability and convenience of HA detection in urine. To the best of our knowledge, this is the first example of dye@MOF based sensor for HA detection. And this work provides a promising approach for developing dye@MOF based sensors to intelligent detect bioactive molecules.