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1.
J Neurosci ; 44(29)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886059

RESUMO

Anxiety-related disorders respond to cognitive behavioral therapies, which involved the medial prefrontal cortex (mPFC). Previous studies have suggested that subregions of the mPFC have different and even opposite roles in regulating innate anxiety. However, the specific causal targets of their descending projections in modulating innate anxiety and stress-induced anxiety have yet to be fully elucidated. Here, we found that among the various downstream pathways of the prelimbic cortex (PL), a subregion of the mPFC, PL-mediodorsal thalamic nucleus (MD) projection, and PL-ventral tegmental area (VTA) projection exhibited antagonistic effects on anxiety-like behavior, while the PL-MD projection but not PL-VTA projection was necessary for the animal to guide anxiety-related behavior. In addition, MD-projecting PL neurons bidirectionally regulated remote but not recent fear memory retrieval. Notably, restraint stress induced high-anxiety state accompanied by strengthening the excitatory inputs onto MD-projecting PL neurons, and inhibiting PL-MD pathway rescued the stress-induced anxiety. Our findings reveal that the activity of PL-MD pathway may be an essential factor to maintain certain level of anxiety, and stress increased the excitability of this pathway, leading to inappropriate emotional expression, and suggests that targeting specific PL circuits may aid the development of therapies for the treatment of stress-related disorders.


Assuntos
Ansiedade , Vias Neurais , Córtex Pré-Frontal , Estresse Psicológico , Animais , Ansiedade/psicologia , Ansiedade/fisiopatologia , Masculino , Estresse Psicológico/psicologia , Estresse Psicológico/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Vias Neurais/fisiopatologia , Vias Neurais/fisiologia , Camundongos , Medo/fisiologia , Medo/psicologia , Camundongos Endogâmicos C57BL , Área Tegmentar Ventral/fisiopatologia , Tálamo/fisiopatologia , Núcleo Mediodorsal do Tálamo/fisiologia , Núcleo Mediodorsal do Tálamo/fisiopatologia
2.
Plant Physiol ; 195(1): 617-639, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38285060

RESUMO

Revealing the genetic basis for stress-resistant traits in extremophile plants will yield important information for crop improvement. Zygophyllum xanthoxylum, an extant species of the ancient Mediterranean, is a succulent xerophyte that can maintain a favorable water status under desert habitats; however, the genetic basis of this adaptive trait is poorly understood. Furthermore, the phylogenetic position of Zygophyllales, to which Z. xanthoxylum belongs, remains controversial. In this study, we sequenced and assembled the chromosome-level genome of Z. xanthoxylum. Phylogenetic analysis showed that Zygophyllales and Myrtales form a separated taxon as a sister to the clade comprising fabids and malvids, clarifying the phylogenetic position of Zygophyllales at whole-genome scale. Analysis of genomic and transcriptomic data revealed multiple critical mechanisms underlying the efficient osmotic adjustment using Na+ and K+ as "cheap" osmolytes that Z. xanthoxylum has evolved through the expansion and synchronized expression of genes encoding key transporters/channels and their regulators involved in Na+/K+ uptake, transport, and compartmentation. It is worth noting that ZxCNGC1;1 (cyclic nucleotide-gated channels) and ZxCNGC1;2 constituted a previously undiscovered energy-saving pathway for Na+ uptake. Meanwhile, the core genes involved in biosynthesis of cuticular wax also featured an expansion and upregulated expression, contributing to the water retention capacity of Z. xanthoxylum under desert environments. Overall, these findings boost the understanding of evolutionary relationships of eudicots, illustrate the unique water retention mechanism in the succulent xerophyte that is distinct from glycophyte, and thus provide valuable genetic resources for the improvement of stress tolerance in crops and insights into the remediation of sodic lands.


Assuntos
Filogenia , Água , Zygophyllum , Água/metabolismo , Zygophyllum/genética , Zygophyllum/metabolismo , Genoma de Planta , Regulação da Expressão Gênica de Plantas , Genômica/métodos
3.
Glia ; 72(9): 1646-1662, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38801194

RESUMO

The adult brain retains a high repopulation capacity of astrocytes after deletion, and both mature astrocytes in the neocortex and neural stem cells in neurogenic regions possess the potential to generate astrocytes. However, the origin and the repopulation dynamics of the repopulating astrocytes after deletion remain largely unclear. The number of astrocytes is reduced in the medial prefrontal cortex (mPFC) of patients with depression, and selective elimination of mPFC astrocytes is sufficient to induce depression-like behaviors in rodents. However, whether astrocyte repopulation capacity is impaired in depression is unknown. In this study, we used different transgenic mouse lines to genetically label different cell types and demonstrated that in the mPFC of normal adult mice of both sexes, mature astrocytes were a major source of the repopulating astrocytes after acute deletion induced by an astrocyte-specific toxin, L-alpha-aminoadipic acid (L-AAA), and astrocyte regeneration was accomplished within two weeks accompanied by reversal of depression-like behaviors. Furthermore, re-ablation of mPFC astrocytes post repopulation led to reappearance of depression-like behaviors. In adult male mice subjected to 14-day chronic restraint stress, a well-validated mouse model of depression, the number of mPFC astrocytes was reduced; however, the ability of mPFC astrocytes to repopulate after L-AAA-induced deletion was largely unaltered. Our study highlights a potentially beneficial role for repopulating astrocytes in depression and provides novel therapeutic insights into enhancing local mature astrocyte generation in depression.


Assuntos
Astrócitos , Depressão , Camundongos Transgênicos , Córtex Pré-Frontal , Animais , Astrócitos/metabolismo , Córtex Pré-Frontal/metabolismo , Masculino , Depressão/genética , Depressão/patologia , Feminino , Camundongos Endogâmicos C57BL , Camundongos , Modelos Animais de Doenças , Restrição Física , Ácido 2-Aminoadípico , Estresse Psicológico/patologia , Estresse Psicológico/metabolismo
4.
Biochem Biophys Res Commun ; 722: 150143, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38795451

RESUMO

Nuclear factor (NF)-κB signaling is not only important for the immune and inflammatory responses but also for the normal development of epithelial cells, such as those in the skin and tooth. Here, we generated epithelial cell-specific p65-deficient (p65Δepi-/-) mice to analyze the roles of NF-κB signaling in epithelial cell developent. Notably, p65Δepi-/- mice exhibited no abnormalities in their appearance compared to the control (p65flox/flox) littermates. Furthermore, no major changes were observed in the skin, hair growth, and shape and color of the incisors and molars. However, 65 % of p65Δepi-/- mice exhibited corneal thickening after 8 weeks of age, and 30 % of p65Δepi-/- mice exhibited hair growth from the mandibular incisors around 24 weeks of age. No hair growth was observed at 36 and 42 weeks of age. However, micro-computed tomography images revealed a large cavity below the mandibular incisors extending to the root of the incisor. Histological analysis revealed that the cavity was occupied by a connective tissue containing hair-like structures with many dark brown granules that disappeared after melanin bleaching, confirming the presence of hair. Although inflammatory cells were also observed near the eruption site of the incisor teeth of p65Δepi-/- mice, no major disturbance was observed in the arrangement of enamel epithelial cells. Overall, these results highlight the role of p65 in the maintenance of epithelial cell homeostasis during aging.


Assuntos
Senescência Celular , Células Epiteliais , Fator de Transcrição RelA , Animais , Camundongos , Envelhecimento/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/citologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais , Fator de Transcrição RelA/metabolismo , Fator de Transcrição RelA/genética
5.
Cancer Cell Int ; 24(1): 223, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943137

RESUMO

BACKGROUND: Multiple genetic and epigenetic regulatory mechanisms are crucial in the development and tumorigenesis process. Transcriptional regulation often involves intricate relationships and networks with post-transcriptional regulatory molecules, impacting the spatial and temporal expression of genes. However, the synergistic relationship between transcription factors and N6-methyladenosine (m6A) modification in regulating gene expression, as well as their influence on the mechanisms underlying the occurrence and progression of non-small cell lung cancer (NSCLC), requires further investigation. The present study aimed to investigate the synergistic relationship between transcription factors and m6A modification on NSCLC. METHODS: The transcription factor NFIC and its potential genes was screened by analyzing publicly available datasets (ATAC-seq, DNase-seq, and RNA-seq). The association of NFIC and its potential target genes were validated through ChIP-qPCR and dual-luciferase reporter assays. Additionally, the roles of NFIC and its potential genes in NSCLC were detected in vitro and in vivo through silencing and overexpression assays. RESULTS: Based on multi-omics data, the transcription factor NFIC was identified as a potential tumor suppressor of NSCLC. NFIC was significantly downregulated in both NSCLC tissues and cells, and when NFIC was overexpressed, the malignant phenotype and total m6A content of NSCLC cells was suppressed, while the PI3K/AKT pathway was inactivated. Additionally, we discovered that NFIC inhibits the expression of METTL3 by directly binding to its promoter region, and METTL3 regulates the expression of KAT2A, a histone acetyltransferase, by methylating the m6A site in the 3'UTR of KAT2A mRNA in NSCLC cells. Intriguingly, NFIC was also found to negatively regulate the expression of KAT2A by directly binding to its promoter region. CONCLUSIONS: Our findings demonstrated that NFIC suppresses the malignant phenotype of NSCLC cells by regulating gene expression at both the transcriptional and post-transcriptional levels. A deeper comprehension of the genetic and epigenetic regulatory mechanisms in tumorigenesis would be beneficial for the development of personalized treatment strategies.

6.
Langmuir ; 40(5): 2729-2744, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38277675

RESUMO

We synthesized Sr-doped spinel CoCr2O4 using the solution combustion method and characterized the structure, morphology, chemical state, and photocatalytic properties through different techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance (EPR), and electrochemical impedance spectroscopy (EIS). 30-50 nm cuboid CoCr2O4 nanocrystals with Sr doping levels ranging from 0 to 0.6% were obtained; the increasing Sr doping deformed the coordination number of Co and Cr, transitioning to octahedral and tetrahedral units, inducing the phase transition from spinel to inverse spinel at 0.6% Sr content. This modification enhanced optical absorption, reduced the energy band gap, increased photoluminescence intensity, and maintained a high-spin state with oxygen vacancies. 0.6% Sr-doped CoCr2O4 demonstrated the highest photocatalytic efficiency at 93%. The XRD structure and photocatalytic activity remained at 87% over 7 cycles after 14 h. Employing degradation pathways and Mott-Schottky curves elucidated the enhancement mechanism.

7.
Pharmacol Res ; 199: 107042, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38142878

RESUMO

Drugs acting on dopamine D2 receptors are widely used for the treatment of several neuropsychiatric disorders, including schizophrenia and depression. Social deficits are a core symptom of these disorders. Pharmacological manipulation of dopamine D2 receptors (Drd2), a Gi-coupled subtype of dopamine receptors, in the medial prefrontal cortex (mPFC) has shown that Drd2 is implicated in social behaviors. However, the type of neurons expressing Drd2 in the mPFC and the underlying circuit mechanism regulating social behaviors remain largely unknown. Here, we show that Drd2 were mainly expressed in pyramidal neurons in the mPFC and that the activation of the Gi-pathway in Drd2+ pyramidal neurons impaired social behavior in male mice. In contrast, the knockdown of D2R in pyramidal neurons in the mPFC enhanced social approach behaviors in male mice and selectively facilitated the activation of mPFC neurons projecting to the nucleus accumbens (NAc) during social interaction. Remarkably, optogenetic activation of mPFC-to-NAc-projecting neurons mimicked the effects of conditional D2R knockdown on social behaviors. Altogether, these results demonstrate a cell type-specific role for Drd2 in the mPFC in regulating social behavior, which may be mediated by the mPFC-to-NAc pathway.


Assuntos
Células Piramidais , Receptores de Dopamina D2 , Camundongos , Masculino , Animais , Receptores de Dopamina D2/metabolismo , Células Piramidais/fisiologia , Neurônios/metabolismo , Córtex Pré-Frontal/metabolismo , Núcleo Accumbens/fisiologia , Comportamento Social
8.
Artigo em Inglês | MEDLINE | ID: mdl-38568073

RESUMO

A novel bacterial strain, designated WL0086T, was isolated from a marine sediment sample collected in Lianyungang city, Jiangsu province, PR China. This strain showed the highest 16S rRNA gene sequence similarity to Geminisphaera colitermitum TAV2T (92.7 %) of the family Opitutaceae, and all the unclassified cultured and uncultured isolates with similarities >95 % were from marine environments. Cells were Gram-stain-negative, aerobic, non-motile cocci with a size of 0.6-0.8 µm in diameter. Strain WL0086T was positive for both oxidase and catalase, and grew at 20-37 °C (optimum, 28 °C), with 1.5-11.0 % NaCl (w/v; optimum, 2.5-4.0 %) and at pH 5.0-9.0 (optimum, pH 7.0). The major polar lipid profile of strain WL0086T consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylcholine. The major isoprenoid quinone was menaquinone-7 and the predominant fatty acids were iso-C14 : 0, anteiso-C15 : 0, C16 : 0 and C16 : 1 ω9c. The complete genome consisted of a chromosome with 6 109 182 bp. The G+C content of genomic DNA was 64.0%. Results of phylogenomic analysis based on the 16S rRNA gene sequence and the whole genome suggested that strain WL0086T formed a distinct clade closely neighbouring the members of the family Opitutaceae. On the basis of phylogenetic, phenotypic, and chemotaxonomic evidences, strain WL0086T should represent a novel genus of the family Opitutaceae, for which the name Actomonas aquatica gen. nov., sp. nov. is proposed. The type strain is WL0086T (=MCCC 1K05844T=JCM 34677T=GDMCC 1.2411T).


Assuntos
Carbono , Fixação de Nitrogênio , Composição de Bases , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana
9.
Exp Brain Res ; 242(3): 769-780, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38310175

RESUMO

Using event-related potentials (ERPs), this study examined the impact of reward expectations on working memory of emotional faces under different levels of cognitive load in a task combining the N-back paradigm and the reward expectation paradigm. The experiment involved presenting high- or low-reward cues followed by an N-back task for emotional faces with different loads. The accuracy results showed that under a high task load, both reward and emotion effects were significantly observed. However, these effects disappeared under a low task load. Analysis of the ERP data revealed that the early P2 and VPP components exhibited greater responses to fearful faces than to neutral faces. In the later stages, the P3 and LPP components showed greater reactions to high rewards than to low rewards. Additionally, the P2 component was found to be modulated by task load in relation to rewards, the EPN component demonstrated task load modulation with respect to emotions, and the N170 component showed an interaction effect between rewards and emotions. These findings imply that load regulates the reward effect and the emotional superiority effect in the process of working memory for emotional faces. In the cognitive processing of working memory, motivation and emotion jointly influence processing. Emotional factors have a greater impact in the early stage of processing, while motivation factors have a greater impact in the late stage of processing.


Assuntos
Eletroencefalografia , Motivação , Humanos , Memória de Curto Prazo , Emoções/fisiologia , Potenciais Evocados/fisiologia , Cognição , Recompensa , Expressão Facial
10.
Bioorg Chem ; 143: 107039, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38134519

RESUMO

Autophagy is a ubiquitous pathological/physiological antioxidant cellular reaction in eukaryotic cells. Vacuolar protein sorting 34 (Vps34 or PIK3C3), which plays a crucial role in autophagy, has received much attention. As the only Class III phosphatidylinositol-3 kinase in mammals, Vps34 participates in vesicular transport, nutrient signaling and autophagy. Dysfunctionality of Vps34 induces carcinogenesis, and abnormal autophagy mediated by dysfunction of Vps34 is closely related to the pathological progression of various human diseases, which makes Vps34 a novel target for tumor immunotherapy. In this review, we summarize the molecular mechanisms underlying macroautophagy, and further discuss the structure-activity relationship of Vps34 inhibitors that have been reported in the past decade as well as their potential roles in anticancer immunotherapy to better understand the antitumor mechanism underlying the effects of these inhibitors.


Assuntos
Autofagia , Classe III de Fosfatidilinositol 3-Quinases , Animais , Humanos , Classe III de Fosfatidilinositol 3-Quinases/metabolismo , Transporte Proteico , Proteínas Relacionadas à Autofagia/metabolismo , Transdução de Sinais , Mamíferos/metabolismo
11.
BMC Public Health ; 24(1): 1541, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849814

RESUMO

BACKGROUND: Dose-response and nonlinear relationships of cigarette exposure with sleep disturbances and depression are warranted, and the potential mechanism of sex hormones in such associations remains unclear. METHODS: Cigarette exposure, trouble sleeping, and depression were assessed by standard questionnaires, and the levels of cotinine and sex steroid hormones were determined among 9900 adults from the National Health and Nutrition Examination Survey (NHANES). Multiple linear regression, logistic regression, and mediation models were conducted to evaluate the associations between smoking, sex steroid hormones, trouble sleeping, and depression. RESULTS: With never smokers as a reference, current smokers had a higher prevalence of trouble sleeping (OR = 1.931, 95% CI: 1.680, 2.219) and depression (OR = 2.525, 95% CI: 1.936, 3.293) as well as testosterone level (ß = 0.083, 95% CI: 0.028, 0.140). Pack-years of smoking and cigarettes per day were positively associated with the prevalence of trouble sleeping and depression as well as testosterone level (Ptrend <0.05). The restricted cubic spline model showed linear relationships of cotinine with trouble sleeping, depression, and testosterone. The positive associations of cigarettes per day with trouble sleeping and depression were greater in females than that in males (Pmodification <0.05). However, the potential role of sex hormones was not observed in the association of cotinine with trouble sleeping or depression (Pmediation >0.05). CONCLUSION: Smoking may induce sex hormone disturbance and increase the risk of sleep problems and depression symptoms, and ceasing smoking may reduce the risk of such complications.


Assuntos
Cotinina , Depressão , Inquéritos Nutricionais , Humanos , Masculino , Feminino , Estudos Transversais , Adulto , Depressão/epidemiologia , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Cotinina/sangue , Cotinina/análise , Transtornos do Sono-Vigília/epidemiologia , Fumar/epidemiologia , Prevalência , Hormônios Esteroides Gonadais/sangue , Adulto Jovem , Testosterona/sangue , Idoso
12.
J Clin Nurs ; 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073235

RESUMO

AIMS AND OBJECTIVES: The main aim of this study is to synthesize the prevalent predictive models for pressure injuries in hospitalized patients, with the goal of identifying common predictive factors linked to pressure injuries in hospitalized patients. This endeavour holds the potential to provide clinical nurses with a valuable reference for providing targeted care to high-risk patients. BACKGROUND: Pressure injuries (PIs) are a frequently occurring health problem throughout the world. There are mounting studies about risk prediction model of PIs reported and published. However, the prediction performance of the models is still unclear. DESIGN: Systematic review and meta-analysis: The Cochrane Library, PubMed, Embase, CINAHL, Web of Science and Chinese databases including CNKI (China National Knowledge Infrastructure), Wanfang Database, Weipu Database and CBM (China Biology Medicine). METHODS: This systematic review was conducted following PRISMA recommendations. The databases of Cochrane Library, PubMed, Embase, CINAHL, Web of Science, and CNKI, Weipu Database, Wanfang Database and CBM were searched for all studies published before September 2023. We included studies with cohort, case-control designs, reporting the development of risk model and have been validated externally and internally among the hospitalized patients. Two researchers selected the retrieved studies according to the inclusion and exclusion criteria, and critically evaluated the quality of studies based on the CHARMS checklist. The PRISMA guideline was used to report the systematic review and meta-analysis. RESULTS: Sixty-two studies were included, which contained 99 pressure injuries risk prediction models. The AUC (area under ROC curve) of modelling in 32 prediction models were reported ranged from .70 to .99, while the AUC of verification in 38 models were reported ranged from .70 to .98. Gender (OR = 1.41, CI: .99 ~ 1.31), age (WMD = 8.81, CI: 8.11 ~ 9.57), diabetes mellitus (OR = 1.64, CI: 1.36 ~ 1.99), mechanical ventilation (OR = 2.71, CI: 2.05 ~ 3.57), length of hospital stay (WMD = 7.65, CI: 7.24 ~ 8.05) were the most common predictors of pressure injuries. CONCLUSION: Studies of PIs risk prediction model in hospitalized patients had high research quality, and the risk prediction models also had good predictive performance. However, some of the included studies lacked of internal or external validation in modelling, which affected the stability and extendibility. The aged, male patient in ICU, albumin, haematocrit, low haemoglobin level, diabetes, mechanical ventilation and length of stay in hospital were high-risk factors for pressure injuries in hospitalized patients. In the future, it is recommended that clinical nurses, in practice, select predictive models with better performance to identify high-risk patients based on the actual situation and provide care targeting the high-risk factors to prevent the occurrence of diseases. RELEVANCE TO CLINICAL PRACTICE: The risk prediction model is an effective tool for identifying patients at the risk of developing PIs. With the help of risk prediction tool, nurses can identify the high-risk patients and common predictive factors, predict the probability of developing PIs, then provide specific preventive measures to improve the outcomes of these patients. REGISTRATION NUMBER (PROSPERO): CRD42023445258.

13.
Inflammopharmacology ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39150492

RESUMO

BACKGROUND AND AIM: Inflammatory diseases often result in bone loss due to persistent inflammation, which activates osteoclasts and increases bone resorption. Oxysophocarpine (OSC), a bioalkaloid extracted from the roots of Sophora japonica and other leguminous plants, has neuroprotective and anti-tumor properties. However, it is still uncertain whether OSC can effectively inhibit the differentiation of osteoclasts and bone resorption. Therefore, this study explored the potential role of OSC in osteoclast formation and inflammatory osteolysis and its underlying mechanisms. EXPERIMENTAL PROCEDURE: This study involved inducing primary mouse bone marrow macrophages (BMMs) into osteoclasts using macrophage colony-stimulating factor (M-CSF) and receptor activator of NF-κB ligand (RANKL) and examined the effects of OSC on osteoclast (OC) differentiation, function, and intracellular reactive oxygen species (ROS) production. The impact of OSC on the expression of osteoclast-specific genes and inflammation-related factors was assessed using real-time quantitative PCR. Additionally, changes in oxidative stress-related factors, NF-κB, and MAPK signaling pathways were examined using western blotting. Finally, this study investigated the influence of OSC on a mouse cranial bone resorption model induced by titanium (Ti) particles in vivo. RESULTS: OSC inhibited OC differentiation and resorption and reduces intracellular ROS levels. Moreover, OSC suppressed IL-1ß, TNF-α, IL-6, and osteoclast-specific gene transcription while increasing Nrf2 and HO-1 protein expression. Furthermore, OSC inhibited the expression and autoregulation of the NFATc1 gene, ultimately leading to a reduction in Ti particle-induced bone resorption in mice. CONCLUSION: OSC could be regarded as an innovative medication for the treatment of osteoclast-associated inflammatory osteolytic diseases.

14.
Mikrochim Acta ; 191(1): 42, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38114730

RESUMO

To avoid false negative results due to the low cross-reactivity rate (CR) in rapid immunoassay, a group-specific antibody with homogeneous CR toward target compounds is needed for accuracy. In this study, tylosin (TYL) and tilmicosin (TM) were selected as model molecules. Firstly, two-dimensional similarity, electrostatic potential energy, spatial conformation and charge distribution of the haptens TYL-CMO, TYL-6-ACA, TYL-4-APA, TYL-CHO and DES-CMO and target compounds of TYL and TM were obtained using Gaussian 09W and Discovery Studio. The optimal hapten was DES-CMO because it is the most similar to TYL and TM. Subsequently, the mAb 14D5 cell line was obtained with IC50 values of 1.59 and 1.72 ng/mL for TYL and TM, respectively, and a CR of 92.44%. Finally, amorphous carbon nanoparticles (ACNPs) were conjugated with mAb 14D5 to develop an accurate lateral flow immunoassay (LFA) for detection of TYL and TM by the reflectance value under natural light. The recoveries of TYL and TM ranged from 77.18 to 112.04% with coefficient of variation < 13.43%. The cut-off value in milk samples was 8 ng/mL, and the limits of detection were 11.44, 15.96, 22.29 and 25.53 µg/kg for chicken muscle, bovine muscle, porcine muscle and porcine liver samples, respectively, and the results being consistent with HPLC-UV. The results suggest that the developed LFA is accurate and potentially useful for on-site screening of TYL and TM in milk and animal tissue samples.


Assuntos
Anticorpos Monoclonais , Tilosina , Animais , Bovinos , Suínos , Ensaio de Imunoadsorção Enzimática/métodos , Imunoensaio , Haptenos
15.
Comput Methods Appl Mech Eng ; 417(Pt B)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38292246

RESUMO

Gradient-based meta-learning methods have primarily been applied to classical machine learning tasks such as image classification. Recently, PDE-solving deep learning methods, such as neural operators, are starting to make an important impact on learning and predicting the response of a complex physical system directly from observational data. Taking the material modeling problems for example, the neural operator approach learns a surrogate mapping from the loading field to the corresponding material response field, which can be seen as learning the solution operator of a hidden PDE. The microstructure and mechanical parameters of each material specimen correspond to the (possibly heterogeneous) parameter field in this hidden PDE. Due to the limitation on experimental measurement techniques, the data acquisition for each material specimen is commonly challenging and costly. This fact calls for the utilization and transfer of existing knowledge to new and unseen material specimens, which corresponds to sampling efficient learning of the solution operator of a hidden PDE with a different parameter field. Herein, we propose a novel meta-learning approach for neural operators, which can be seen as transferring the knowledge of solution operators between governing (unknown) PDEs with varying parameter fields. Our approach is a provably universal solution operator for multiple PDE solving tasks, with a key theoretical observation that underlying parameter fields can be captured in the first layer of neural operator models, in contrast to typical final-layer transfer in existing meta-learning methods. As applications, we demonstrate the efficacy of our proposed approach on PDE-based datasets and a real-world material modeling problem, illustrating that our method can handle complex and nonlinear physical response learning tasks while greatly improving the sampling efficiency in unseen tasks.

17.
Methods Mol Biol ; 2794: 341-351, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38630243

RESUMO

Single-cell RNA sequencing (scRNA-seq) has been widely applied in neuroscience research, enabling the investigation of cellular heterogeneity at the transcriptional level, the characterization of rare cell types, and the detailed analysis of the stochastic nature of gene expression. Isolation of single nerve cells in good health, especially from the adult rodent brain, is the most difficult and critical process for scRNA-seq. Here, we describe methods to optimize protease digestion of brain slices, which enable yield of millions of cells in good health from the adult brain.


Assuntos
Astrócitos , Neurônios , Animais , Camundongos , RNA-Seq , Encéfalo , Endopeptidases , Suspensões
18.
Neural Netw ; 172: 106133, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38266471

RESUMO

Vision Transformer (ViT) has performed remarkably in various computer vision tasks. Nonetheless, affected by the massive amount of parameters, ViT usually suffers from serious overfitting problems with a relatively limited number of training samples. In addition, ViT generally demands heavy computing resources, which limit its deployment on resource-constrained devices. As a type of model-compression method, model binarization is potentially a good choice to solve the above problems. Compared with the full-precision one, the model with the binarization method replaces complex tensor multiplication with simple bit-wise binary operations and represents full-precision model parameters and activations with only 1-bit ones, which potentially solves the problem of model size and computational complexity, respectively. In this paper, we investigate a binarized ViT model. Empirically, we observe that the existing binarization technology designed for Convolutional Neural Networks (CNN) cannot migrate well to a ViT's binarization task. We also find that the decline of the accuracy of the binary ViT model is mainly due to the information loss of the Attention module and the Value vector. Therefore, we propose a novel model binarization technique, called Group Superposition Binarization (GSB), to deal with these issues. Furthermore, in order to further improve the performance of the binarization model, we have investigated the gradient calculation procedure in the binarization process and derived more proper gradient calculation equations for GSB to reduce the influence of gradient mismatch. Then, the knowledge distillation technique is introduced to alleviate the performance degradation caused by model binarization. Analytically, model binarization can limit the parameter's search space during parameter updates while training a model. Therefore, the binarization process can actually play an implicit regularization role and help solve the problem of overfitting in the case of insufficient training data. Experiments on three datasets with limited numbers of training samples demonstrate that the proposed GSB model achieves state-of-the-art performance among the binary quantization schemes and exceeds its full-precision counterpart on some indicators. Code and models are available at: https://github.com/IMRL/GSB-Vision-Transformer.


Assuntos
Compressão de Dados , Conhecimento , Redes Neurais de Computação
19.
Cogn Neurodyn ; 18(4): 2061-2075, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39104690

RESUMO

Vibration is an indispensable part of the tactile perception, which is encoded to oscillatory synaptic currents by receptors and transferred to neurons in the brain. The A2 and B1 neurons in the drosophila brain postsynaptic to the vibration receptors exhibit selective preferences for oscillatory synaptic currents with different frequencies, which is caused by the specific voltage-gated Na+ and K+ currents that both oppose the variations in membrane potential. To understand the peculiar role of the Na+ and K+ currents in shaping the filtering property of A2 and B1 neurons, we develop a linearized modeling framework that allows to systematically change the activation properties of these ionic channels. A data-driven conductance-based biophysical model is used to reproduce the frequency filtering of oscillatory synaptic inputs. Then, this data-driven model is linearized at the resting potential and its frequency response is calculated based on the transfer function, which is described by the magnitude-frequency curve. When we regulate the activation properties of the Na+ and K+ channels by changing the biophysical parameters, the dominant pole of the transfer function is found to be highly correlated with the fluctuation of the active current, which represents the strength of suppression of slow voltage variation. Meanwhile, the dominant pole also shapes the magnitude-frequency curve and further qualitatively determines the filtering property of the model. The transfer function provides a parsimonious description of how the biophysical parameters in Na+ and K+ channels change the inhibition of slow variations in membrane potential by Na+ and K+ currents, and further illustrates the relationship between the filtering properties and the activation properties of Na+ and K+ channels. This computational framework with the data-driven conductance-based biophysical model and its linearized model contributes to understanding the transmission and filtering of vibration stimulus in the tactile system.

20.
Front Behav Neurosci ; 18: 1433649, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38993267

RESUMO

Introduction: Reward and punishment modulate behavior. In real-world motor skill learning, reward and punishment have been found to have dissociable effects on optimizing motor skill learning, but the scientific basis for these effects is largely unknown. Methods: In the present study, we investigated the effects of reward and punishment on the performance of real-world motor skill learning. Specifically, three groups of participants were trained and tested on a ping-pong ball bouncing task for three consecutive days. The training and testing sessions were identical across the three days: participants were trained with their right (dominant) hand each day under conditions of either reward, punishment, or a neutral control condition (neither). Before and after the training session, all participants were tested with their right and left hands without any feedback. Results: We found that punishment promoted early learning, while reward promoted late learning. Reward facilitated short-term memory, while punishment impaired long-term memory. Both reward and punishment interfered with long-term memory gains. Interestingly, the effects of reward and punishment transferred to the left hand. Discussion: The results show that reward and punishment have different effects on real-world motor skill learning. The effects change with training and transfer readily to novel contexts. The results suggest that reward and punishment may act on different learning processes and engage different neural mechanisms during real-world motor skill learning. In addition, high-level metacognitive processes may be enabled by the additional reinforcement feedback during real-world motor skill learning. Our findings provide new insights into the mechanisms underlying motor learning, and may have important implications for practical applications such as sports training and motor rehabilitation.

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