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1.
Nat Sci Sleep ; 16: 725-735, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38873239

RESUMO

Purpose: This study aimed to evaluate nocturnal sleep structure and anxiety, depression, and fatigue in patients with narcolepsy type 1 (NT1). Methods: Thirty NT1 patients and thirty-five healthy controls were enrolled and evaluated using the Epworth sleepiness scale (ESS), Generalized Anxiety Disorder-7, Patient Health Questionnaire-9, Fatigue Severity Scale (FSS), polysomnography, multiple sleep latency test, and brain function state monitoring. Statistical analyses were performed using SPSS Statistics for Windows, version 23.0. Benjamini-Hochberg correction was performed to control the false discovery rate. Results: Apart from typical clinical manifestations, patients with NT1 are prone to comorbidities such as nocturnal sleep disorders, anxiety, depression, and fatigue. Compared with the control group, patients with NT1 exhibited abnormal sleep structure, including increased total sleep time (P adj=0.007), decreased sleep efficiency (P adj=0.002), shortening of sleep onset latency (P adj<0.001), elevated wake after sleep onset (P adj=0.002), increased N1% (P adj=0.006), and reduced N2%, N3%, and REM% (P adj=0.007, P adj<0.001, P adj=0.013). Thirty-seven percent of patients had moderate to severe obstructive sleep apnea-hypopnea syndrome. And sixty percent of patients were complicated with REM sleep without atonia. Patients with NT1 displayed increased anxiety propensity (P adj<0.001), and increased brain fatigue (P adj=0.020) in brain function state monitoring. FSS scores were positively correlated with brain fatigue (P adj<0.001) and mean sleep latency was inversely correlated with FSS scores and brain fatigue (P adj=0.013, P adj=0.029). Additionally, ESS scores and brain fatigue decreased after 3 months of therapy (P=0.012, P=0.030). Conclusion: NT1 patients had abnormal nocturnal sleep structures, who showed increased anxiety, depression, and fatigue. Excessive daytime sleepiness and fatigue improved after 3 months of treatment with methylphenidate hydrochloride prolonged-release tablets in combination with venlafaxine.

2.
ACS Omega ; 9(16): 18576-18583, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38680347

RESUMO

Paraquat (PQ) poisoning poses a significant public health concern. Unfortunately, point-of-care testing (POCT) of PQ in biofluids remains challenging. This study developed a portable kit that enables swift and reliable identification and quantification of PQ in human urine and gastric juice. The approach employed the surface-enhanced Raman scattering (SERS) technique, leveraging gold-silver core-shell nanoparticles (Au@Ag NPs) as the substrate. The kit comprised a portable Raman spectrometer and three sealed tubes containing Au@Ag NPs colloid, KI solution, and MgSO4 solution. A discernible correlation was observed between signal intensity and the logarithmic concentration, spanning from 5 to 500 µg/L in urine and 10 µg/L to 1 mg/L in gastric juice. The detection limits, calculated from the characteristic peak at 1648 cm -1, were 1.36 and 4.05 µg/L in human urine and gastric juice, respectively. Notably, this POCT kit obviated the need for pretreatment procedures, and the detection process was accomplished within 1 min, yielding satisfactory recoveries. This expeditious time frame is crucial for clinical diagnosis and rescue operations. Compared to conventional methods, this kit demonstrated real-time determinations in nonlaboratory settings. The simplicity and practicality of this POCT assay suggest its significant potential as an innovative alternative for poisoning detection applications.

3.
Sensors (Basel) ; 24(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38339540

RESUMO

The accurate estimation of the remaining useful life (RUL) for aircraft engines is essential for ensuring safety and uninterrupted operations in the aviation industry. Numerous investigations have leveraged the success of the attention-based Transformer architecture in sequence modeling tasks, particularly in its application to RUL prediction. These studies primarily focus on utilizing onboard sensor readings as input predictors. While various Transformer-based approaches have demonstrated improvement in RUL predictions, their exclusive focus on temporal attention within multivariate time series sensor readings, without considering sensor-wise attention, raises concerns about potential inaccuracies in RUL predictions. To address this concern, our paper proposes a novel solution in the form of a two-stage attention-based hierarchical Transformer (STAR) framework. This approach incorporates a two-stage attention mechanism, systematically addressing both temporal and sensor-wise attentions. Furthermore, we enhance the STAR RUL prediction framework by integrating hierarchical encoder-decoder structures to capture valuable information across different time scales. By conducting extensive numerical experiments with the CMAPSS datasets, we demonstrate that our proposed STAR framework significantly outperforms the current state-of-the-art models for RUL prediction.

4.
J Neurosci ; 44(4)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38050130

RESUMO

Body movements influence brain-wide neuronal activities. In the sensory cortex, thalamocortical bottom-up inputs and motor-sensory top-down inputs are thought to affect the dynamics of membrane potentials (Vm ) of neurons and change their processing of sensory information during movements. However, direct perturbation of the axons projecting to the sensory cortex from other remote areas during movements has remained unassessed, and therefore the interareal circuits generating motor-related signals in sensory cortices remain unclear. Using a Gi/o -coupled opsin, eOPN3, we here inhibited interareal signals incoming to the whisker primary somatosensory barrel cortex (wS1) of awake male mice and tested their effects on whisking-related changes in neuronal activities in wS1. Spontaneous whisking in air induced the changes in spike rates of a subset of wS1 neurons, which were accompanied by depolarization and substantial reduction of slow-wave oscillatory fluctuations of Vm Despite an extensive innervation, inhibition of inputs from the whisker primary motor cortex (wM1) to wS1 did not alter the spike rates and Vm dynamics of wS1 neurons during whisking. In contrast, inhibition of axons from the whisker-related thalamus (wTLM) and the whisker secondary somatosensory cortex (wS2) to wS1 largely attenuated the whisking-related supra- and sub-threshold Vm dynamics of wS1 neurons. Notably, silencing inputs from wTLM markedly decreased the modulation depth of whisking phase-tuned neurons in wS1, while inhibiting wS2 inputs did not impact the whisking variable tuning of wS1 neurons. Thus, sensorimotor integration in wS1 during spontaneous whisking is predominantly facilitated by direct synaptic inputs from wTLM and wS2 rather than from wM1.


Assuntos
Neurônios , Córtex Somatossensorial , Camundongos , Masculino , Animais , Neurônios/fisiologia , Córtex Somatossensorial/fisiologia , Axônios , Potenciais da Membrana , Movimento , Vibrissas/fisiologia
5.
J Neurochem ; 167(5): 680-695, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37924268

RESUMO

Membrane trafficking pathways mediate key microglial activities such as cell migration, cytokine secretion, and phagocytosis. However, the underlying molecular mechanism remains poorly understood. Previously, we found that synaptotagmin-11 (Syt11), a non-Ca2+ -binding Syt associated with Parkinson's disease (PD) and schizophrenia, inhibits cytokine release and phagocytosis in primary microglia. Here we reported the in vivo function of Syt11 in microglial immune responses using an inducible microglia-specific Syt11-conditional-knockout (cKO) mouse strain. Syt11-cKO resulted in activation of microglia and elevated mRNA levels of IL-6, TNF-α, IL-1ß, and iNOS in various brain regions under both resting state and LPS-induced acute inflammation state in adult mice. In a PD mouse model generated by microinjection of preformed α-synuclein fibrils into the striatum, a reduced number of microglia migrated toward the injection sites and an enhanced phagocytosis of α-synuclein fibrils by microglia were found in Syt11-cKO mice. To understand the molecular mechanism of Syt11 function, we identified its direct binding proteins vps10p-tail-interactor-1a (vti1a) and vti1b. The linker domain of Syt11 interacted with both proteins and a peptide derived from it competitively inhibited the interaction of Syt11 with vti1a/vti1b in vitro and in cells. Importantly, application of this peptide induced more cytokine secretion in wild-type microglia upon LPS treatment, phenocopying defects in Syt11 knockdown cells. Altogether, we propose that Syt11 inhibits microglial activation in vivo and regulates cytokine secretion through interactions with vti1a and vti1b.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Animais , Camundongos , alfa-Sinucleína/metabolismo , Citocinas/metabolismo , Lipopolissacarídeos/farmacologia , Microglia/metabolismo , Doença de Parkinson/metabolismo , Fagocitose , Sinaptotagminas/genética
6.
Brief Bioinform ; 24(5)2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37649385

RESUMO

Protein crystallization is crucial for biology, but the steps involved are complex and demanding in terms of external factors and internal structure. To save on experimental costs and time, the tendency of proteins to crystallize can be initially determined and screened by modeling. As a result, this study created a new pipeline aimed at using protein sequence to predict protein crystallization propensity in the protein material production stage, purification stage and production of crystal stage. The newly created pipeline proposed a new feature selection method, which involves combining Chi-square (${\chi }^{2}$) and recursive feature elimination together with the 12 selected features, followed by a linear discriminant analysisfor dimensionality reduction and finally, a support vector machine algorithm with hyperparameter tuning and 10-fold cross-validation is used to train the model and test the results. This new pipeline has been tested on three different datasets, and the accuracy rates are higher than the existing pipelines. In conclusion, our model provides a new solution to predict multistage protein crystallization propensity which is a big challenge in computational biology.


Assuntos
Algoritmos , Aprendizado de Máquina , Cristalização , Sequência de Aminoácidos , Biologia Computacional
7.
Curr Biol ; 33(16): 3436-3451.e7, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37536343

RESUMO

During reward-based learning tasks, animals make orofacial movements that globally influence brain activity at the timings of reward expectation and acquisition. These orofacial movements are not explicitly instructed and typically appear along with goal-directed behaviors. Here, we show that reinforcing optogenetic stimulation of dopamine neurons in the ventral tegmental area (oDAS) in mice is sufficient to induce orofacial movements in the whiskers and nose without accompanying goal-directed behaviors. Pavlovian conditioning with a sensory cue and oDAS elicited cue-locked and oDAS-aligned orofacial movements, which were distinguishable by a machine-learning model. Inhibition or knockout of dopamine D1 receptors in the nucleus accumbens inhibited oDAS-induced motion but spared cue-locked motion, suggesting differential regulation of these two types of orofacial motions. In contrast, inactivation of the whisker primary motor cortex (wM1) abolished both types of orofacial movements. We found specific neuronal populations in wM1 representing either oDAS-aligned or cue-locked whisker movements. Notably, optogenetic stimulation of wM1 neurons successfully replicated these two types of movements. Our results thus suggest that accumbal D1-receptor-dependent and -independent neuronal signals converge in the wM1 for facilitating distinct uninstructed orofacial movements during a reward-based learning task.


Assuntos
Núcleo Accumbens , Área Tegmentar Ventral , Camundongos , Animais , Núcleo Accumbens/fisiologia , Área Tegmentar Ventral/fisiologia , Movimento , Neurônios Dopaminérgicos/fisiologia , Receptores de Dopamina D1 , Recompensa
8.
J Neurosci ; 43(36): 6230-6248, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37474308

RESUMO

Synaptic vesicle (SV) endocytosis is a critical and well-regulated process for the maintenance of neurotransmission. We previously reported that synaptotagmin-11 (Syt11), an essential non-Ca2+-binding Syt associated with brain diseases, inhibits neuronal endocytosis (Wang et al., 2016). Here, we found that Syt11 deficiency caused accelerated SV endocytosis and vesicle recycling under sustained stimulation and led to the abnormal membrane partition of synaptic proteins in mouse hippocampal boutons of either sex. Furthermore, our study revealed that Syt11 has direct but Ca2+-independent binding with endophilin A1 (EndoA1), a membrane curvature sensor and endocytic protein recruiter, with high affinity. EndoA1-knockdown significantly reversed Syt11-KO phenotype, identifying EndoA1 as a main inhibitory target of Syt11 during SV endocytosis. The N-terminus of EndoA1 and the C2B domain of Syt11 were responsible for this interaction. A peptide (amino acids 314-336) derived from the Syt11 C2B efficiently blocked Syt11-EndoA1 binding both in vitro and in vivo Application of this peptide inhibited SV endocytosis in WT hippocampal neurons but not in EndoA1-knockdown neurons. Moreover, intracellular application of this peptide in mouse calyx of Held terminals of either sex effectively hampered both fast and slow SV endocytosis at physiological temperature. We thus propose that Syt11 ensures the precision of protein retrieval during SV endocytosis by inhibiting EndoA1 function at neuronal terminals.SIGNIFICANCE STATEMENT Endocytosis is a key stage of synaptic vesicle (SV) recycling. SV endocytosis retrieves vesicular membrane and protein components precisely to support sustained neurotransmission. However, the molecular mechanisms underlying the regulation of SV endocytosis remain elusive. Here, we reported that Syt11-KO accelerated SV endocytosis and impaired membrane partition of synaptic proteins. EndoA1 was identified as a main inhibitory target of Syt11 during SV endocytosis. Our study reveals a novel inhibitory mechanism of SV endocytosis in preventing hyperactivation of endocytosis, potentially safeguarding the recycling of synaptic proteins during sustained neurotransmission.


Assuntos
Transmissão Sináptica , Vesículas Sinápticas , Animais , Camundongos , Endocitose , Neurônios/fisiologia , Transmissão Sináptica/fisiologia , Vesículas Sinápticas/metabolismo , Sinaptotagminas/genética , Sinaptotagminas/metabolismo
9.
Acta Biochim Pol ; 70(1): 109-115, 2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36773307

RESUMO

Anaplastic thyroid cancer (ATC) is a rare but lethal human malignant cancer with no known cure. Ellagic acid (EA), a natural plant extract, has shown antitumor activity against multiple cancers; however, its effects on the malignant phenotypes of ATC cells remain unknown. This study aimed to evaluate the effects of EA on proliferation, migration, and invasion of ATC cells and further explore the associated signaling mechanisms. The normal human thyroid cell line Nthy-ori3-1 and ATC cell line BHT-101 were used. Cytotoxicity assay was performed using the Cell Counting kit-8 (CCK-8) assay. Cell proliferation, migration, and invasion assays were performed using the CCK-8 and colony formation, wound healing, and Transwell invasion assays, respectively. Western blotting was used to detect the levels of related proteins. ß-catenin nuclear protein levels were measured to evaluate the Wnt/ß-catenin pathway. The phosphorylation level of the Akt protein was measured and calculated to evaluate the PI3K/Akt pathway. LiCl and IGF-1 were used as pathway agonists to determine the involvement of the corresponding pathway. The results showed that EA inhibited the proliferation, migration, and invasion of ATC cells. Furthermore, both the Wnt/ß-catenin and PI3K/Akt pathways were suppressed by EA treatment, and activation of these two pathways reversed the EA-induced inhibition of the pathological phenotypes of ATC cells. These findings demonstrate that EA inhibits proliferation, migration, and invasion of ATC cells by suppressing the Wnt/ß-catenin and PI3K/Akt pathways, suggesting that EA is a potential drug candidate for treating ATC and provides a theoretical basis for further in vivo experiments and clinical applications.


Assuntos
Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Humanos , beta Catenina/metabolismo , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Ácido Elágico/farmacologia , Carcinoma Anaplásico da Tireoide/tratamento farmacológico , Carcinoma Anaplásico da Tireoide/genética , Carcinoma Anaplásico da Tireoide/metabolismo , Movimento Celular/genética , Via de Sinalização Wnt/genética , Proliferação de Células , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Regulação Neoplásica da Expressão Gênica
11.
Biosens Bioelectron ; 225: 115083, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36716572

RESUMO

Rapid detection of diquat (DQ) is essential in clinical diagnosis and rescue. Here, we developed a fast, simple-yet-practical detection strategy for the reliable identification and quantification of DQ in biological fluids. Based on surface-enhanced Raman spectroscopy (SERS), point-of-care detection was realized under the acidic condition with gold nanoparticles as the substrate. Under optimal experimental conditions, the detection limits of the strategy were 17.5 ppb and 1.99 ppm in human urine and gastric juice, respectively. High specificity and selectivity of the SERS strategy were demonstrated using common pesticides and coexisting biological substances. The method was also used to detect biofluids from 5 patients and urine samples from 10 healthy volunteers. The results were in high agreement with spectrophotometric and clinical liquid chromatography-mass spectrometry methods. The volume of urine samples required for this technique is merely 20 µL, and no preparation of the samples is required. Compared to traditional methods used in clinical settings, SERS-based methods are capable of real-time measurements that accurately provide rapid detection and response in non-laboratory settings, with great potential for on-site and point-of-care testing.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Praguicidas , Humanos , Diquat , Ouro/química , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos
12.
J Am Soc Mass Spectrom ; 34(1): 48-63, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36507850

RESUMO

Asphaltenes, a major and undesirable component of heavy crude oil, contain many different types of large aromatic compounds. These compounds include nitrogen-containing heteroaromatic compounds that are thought to be the main culprit in the deactivation of catalysts in crude oil refinery processes. Unfortunately, prevention of this is challenging as the structures and properties of the nitrogen-containing heteroaromatic compounds are poorly understood. To facilitate their structural characterization, an approach based on ion-trap collision-activated dissociation (ITCAD) tandem mass spectrometry followed by energy-resolved medium-energy collision-activated dissociation (ER-MCAD) was developed for the differentiation of seven isomeric molecular radical cations of n-pentylquinoline. The fragmentation of each isomer was found to be distinctly different and depended largely on the site of the alkyl side chain in the quinoline ring. In order to better understand the observed fragmentation pathways, mechanisms for the formation of several fragment ions were delineated based on quantum chemical calculations. The fast benzylic α-bond cleavage that dominates the fragmentation of analogous nonheteroaromatic alkylbenzenes was only observed for the 3-isomer as the major pathway due to the lack of favorable low-energy rearrangement reactions. All the other isomeric ions underwent substantially lower-energy rearrangement reactions as their alkyl chains were found to interact mostly via 6-membered transition states either with the quinoline nitrogen (2- and 8-isomers) or the adjacent carbon atom in the quinoline core (4-, 5-, 6-, and 7-isomers), which lowered the activation energies of the fragmentation reactions. The presented analytical approach will facilitate the structural characterization of nitrogen-containing heteroaromatic compounds in asphaltenes.

13.
Front Immunol ; 14: 1302514, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38173730

RESUMO

Autoimmune glial fibrillary acidic protein astrocytopathy (GFAP-A) is a recently discovered autoimmune inflammatory disease of the central nervous system. It presents with a variety of clinical symptoms, including fever, seizures, psychiatric symptoms, limber weakness, and sensory symptoms. However, the symptoms of sleep disorders have not been sufficiently addressed. Here, we report a case of GFAP-A in which the patient complained of excessive daytime sleepiness and an excessive need for sleep. Our patient was a 58-year-old male who experienced excessive daytime sleepiness for 50 days following SARS-CoV-2 infection. He was diagnosed with coronavirus disease 2019 on June 1st. On the 7th of June, he experienced excessive daytime sleepiness, nausea, reduced food intake, lower limb weakness, and dysuria. Subsequently, his sleepiness significantly deteriorated on July 21st. Five months prior, the patient underwent laparoscopic partial right nephrectomy for clear-cell renal cell carcinoma. Brain MRI revealed abnormal hyperintense lesions in the pontine brain and around the mesencephalic aqueduct on T2 and T2-fluid attenuated inversion recovery (T2-FLAIR) sequences However, these lesions did not exhibit any pathological enhancement. Spinal cord MRI revealed lesions in the C6-C7 and T2-T3 segments on the T2 sequence. His Epworth Sleepiness Scale (ESS) score was 16 (reference range, <10), and 24-hour polysomnography supported the diagnosis of rapid-eye-movement sleep disorder and severe sleep apnea-hypopnea syndrome. Glial fibrillary acidic protein IgG antibodies were detected in the cerebrospinal fluid (1:32, cell-based assay) but not in the serum. The level of hypocretin in the cerebrospinal fluid was 29.92 pg/mL (reference range ≥110 pg/mL), suggesting narcolepsy type 1. After treatment with corticosteroids for approximately 1 month, the patient showed considerable clinical and radiological improvement, as well as an increase in hypocretin levels. Although repeated polysomnography and multiple sleep latency tests suggested narcolepsy, his ESS score decreased to 8. Our findings broaden the range of clinical manifestations associated with GFAP-A, thereby enhancing diagnostic and therapeutic strategies for this disease. Additionally, our results indicate a potential common autoimmune mechanism involving GFAP-A and orexin system dysregulation, warranting further investigation.


Assuntos
Distúrbios do Sono por Sonolência Excessiva , Narcolepsia , Masculino , Humanos , Pessoa de Meia-Idade , Orexinas , Proteína Glial Fibrilar Ácida , Sonolência , Distúrbios do Sono por Sonolência Excessiva/diagnóstico , Distúrbios do Sono por Sonolência Excessiva/etiologia , Distúrbios do Sono por Sonolência Excessiva/líquido cefalorraquidiano
14.
J Am Soc Mass Spectrom ; 33(10): 1850-1857, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36106724

RESUMO

Chemical characterization of complex mixtures of large alkanes is critically important for many fields, including petroleomics and the development of renewable transportation fuels. Tandem mass spectrometry is the only analytical method that can be used to characterize such mixtures at the molecular level. Many ionization methods used in mass spectrometry involve proton transfer to the analyte. Unfortunately, very few proton affinity (PA) values are available for alkanes. Indeed, previous research has shown that most protonated alkanes (MH+) are not stable but fragment spontaneously via the elimination of a hydrogen molecule to form [M - H]+ ions. Here, the PAs of several n-alkanes and alkylcyclohexanes containing 5-8 carbon atoms, n-pentane, n-hexane, n-heptane, n-octane, cyclohexane, methylcyclohexane, and ethylcyclohexane, were determined via bracketing experiments by using a linear quadrupole ion trap mass spectrometer. Monitoring the formation of the [M - H]+ ions in reactions between the alkanes and protonated reference bases with known PAs revealed that the PAs of all the alkanes fell into the range 721 ± 20 kJ mol-1. In order to obtain a more accurate estimate of the relative PAs of different alkanes, two alkanes were introduced simultaneously into the ion trap and allowed to react with the same protonated reference base. Based on these experiments, the longer the alkyl chain in an n-alkane or alkylcyclohexane the greater the PA. Further, when considering alkanes with the same number of carbon atoms, the PAs of those with a cyclohexane ring were found to be greater than those with no such ring.

15.
Anal Chem ; 94(40): 13795-13803, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36154017

RESUMO

N-Nitrosamines are strictly regulated in pharmaceutical products due to their carcinogenic nature. Therefore, the ability to rapidly and reliably identify the N-nitroso functionality is urgently needed. Unfortunately, not all ionized N-nitroso compounds produce diagnostic fragment ions and hence tandem mass spectrometry based on collision-activated dissociation (CAD) cannot be used to consistently identify the N-nitroso functionality. Therefore, a more reliable method was developed based on diagnostic functional-group selective ion-molecule reactions in a linear quadrupole ion trap mass spectrometer. 2-Methoxypropene (MOP) was identified as a reagent that reacts with protonated N-nitrosamines in a diagnostic manner by forming an adduct followed by the elimination of 2-propenol (CH3C(OH)═CH2]). From 18 protonated N-nitrosamine model compounds studied, 15 formed the diagnostic product ion. The lack of the diagnostic reaction for three of the N-nitrosamine model compounds was rationalized based on the presence of a pyridine ring that gets preferentially protonated instead of the N-nitroso functionality. These N-nitrosamines can be identified by subjecting a stable adduct formed upon ion-molecule reactions with MOP to CAD. Further, the ability to use ion-molecule reactions followed by CAD to differentiate protonated O-nitroso compounds with a pyridine ring from analogous N-nitrosamines was demonstrated This methodology is considered to be robust for the identification of the N-nitroso functionality in unknown analytes. Lastly, HPLC/MS2 experiments were performed to determine the detection limit for five FDA regulated N-nitrosamines.


Assuntos
Nitrosaminas , Espectrometria de Massas em Tandem , Íons/química , Preparações Farmacêuticas , Piridinas , Espectrometria de Massas em Tandem/métodos
16.
Sensors (Basel) ; 22(14)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35891115

RESUMO

In this paper, a novel two-stage subspace-based direction of arrival (DOA) estimation algorithm with the nested array is proposed for mixed signals containing circular and non-circular ones. By exploiting the difference between the two types of steering vectors, the DOAs of circular signals are estimated in the first stage. After eliminating the estimated information of circular signals by the covariance matrix reconstruction and oblique projection methods, the dimensions of the noise subspace are increased in estimating the DOAs of non-circular signals in the second stage. Through the two-stage estimation, the DOAs of the circular and non-circular signals are estimated separately and different types of signals with similar or the same DOAs can be distinguished. Furthermore, to avoid the two-dimensional (2-D) search with huge computational burden, a one-dimensional (1-D) search method exploiting the rank deficiency is proposed in the DOA estimation for non-circular signals. The simulation results show that the proposed algorithm can effectively improve the estimation accuracy and resolution probability, especially when circular and non-circular signals have similar DOAs.

17.
Front Mol Biosci ; 9: 807622, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35647031

RESUMO

Background: Dysregulation of RNA-binding proteins (RBPs) in cancers is associated with immune and cancer development. Here, we aimed to profile immune-related RBPs in lung adenocarcinoma (LUAD) and construct an immune-related RBP signature (IRBPS) to predict the survival and response to immunotherapy. Methods: A correlation analysis was performed to establish a co-expression network of RBPs and immune-related genes (IRGs) to characterize immune-related RBPs in the TCGA-LUAD cohort (n = 497 cases). Then, a combination of the Random survival forest (RSF) and Cox regression analysis was performed to screen the RBPs and establish IRBPS. This was followed by independent validation of IRBPS in GSE72094 (n = 398 cases), GSE31210, (n = 226 cases), and GSE26939 (n = 114 cases). Differences between the low- and high-risk groups were compared in terms of gene mutations, tumor mutation burden, tumor-infiltrating lymphocytes, and biomarkers responsive to immunotherapy. Results: DDX56, CTSL, ZC3H12D, and PSMC5 were selected and used to construct IRBPS. The high-risk scores of patients had a significantly worse prognosis in both training and testing cohorts (p < 0.0001 and p < 0.05, respectively), and they tended to be older and have an advanced TNM stage. Furthermore, IRBPS was a prognostic factor independent of age, gender, smoking history, TNM stage, and EGFR mutation status (p = 0.002). In addition, high-risk scores of IRBPS were significantly correlated with tumor-infiltrating lymphocytes (p < 0.05). They also had a high level of PD-L1 protein expression (p < 0.01), number of neoantigens (p < 0.001), and TMB (p < 0.001), implying the possible prediction of IRBPS in the immunotherapy of LUAD. Conclusion: The currently established IRBPS encompassing immune-related RBPs might serve as a promising tool to predict survival, reflect the immune microenvironment, and predict the efficacy of immunotherapy among LUAD patients.

18.
J Immunol ; 208(7): 1616-1631, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35321881

RESUMO

IL-2 is a pleiotropic cytokine that is critical for T cell immunity. Although the IL-2-mediated regulation of T cell immunity in mammals is relatively well understood, it remains largely unknown whether and how IL-2 regulates T cell immunity in lower vertebrates. To address this knowledge gap, we investigated the role played by IL-2 in the regulation of T cell response, as well as the associated underlying mechanisms in a teleost fish, large yellow croaker (Larimichthys crocea). We found that large yellow croaker (L. crocea) IL-2 (LcIL-2) significantly promoted T cell proliferation both in vivo and in vitro; significantly induced the differentiation of Th1, Th2, regulatory T, and cytotoxic T cells while inhibiting Th17 differentiation; and participated in the elimination of invading pathogenic bacteria. Mechanistically, the binding of LcIL-2 to its heterotrimer receptor complex (LcIL-15Rα/LcIL-2Rß/Lcγc) triggered the conserved JAK-STAT5 pathway, which in turn regulated the expression of genes involved in T cell expansion, differentiation, and biological function. The MAPK and mammalian target of rapamycin complex 1 (mTORC1) axes, which are involved in TCR-mediated signaling, were also required for LcIL-2-mediated T cell response. Collectively, our results demonstrated that fish IL-2 plays a comprehensive regulatory role in T cell response and highlighted the complex and delicate network regulating T cell-driven immune response. We propose that T cell immunity is regulated by the interplay between TCR signaling and cytokine signaling, and that this basic strategy evolved before the emergence of the tetrapod lineage. Our findings provide valuable insights into the regulatory mechanisms underlying T cell response in teleosts.


Assuntos
Proteínas de Peixes , Interleucina-2 , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteínas Quinases Ativadas por Mitógeno , Linfócitos T , Animais , Proliferação de Células , Proteínas de Peixes/metabolismo , Peixes , Interleucina-2/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Linfócitos T/citologia
19.
Fish Shellfish Immunol ; 119: 262-271, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34653664

RESUMO

ATG12, a core autophagy protein, forms a conjugate with ATG5 to promote the formation of autophagosome membrane, and plays an important role in antiviral immunity. However, little is known about the function of ATG12 in fish. Here, we cloned the open reading frame (ORF) of large yellow croaker (Larimichthys crocea) ATG12 (LcATG12), which is 354 nucleotides long and encodes a protein of 117 amino acids. The deduced LcATG12 possesses a conserved APG12 domain (residues 31 to 117), and shares 91.45% identities with ATG12 in orange-spotted grouper (Epinephelus coioides). LcATG12 was constitutively expressed in all examined tissues, with the highest level in intestine. Its transcript was also detected in primary head kidney granulocytes (PKG), primary head kidney macrophages (PKM), primary head kidney lymphocytes (PKL), and large yellow croaker head kidney (LYCK) cell line, and was significantly up-regulated by poly(I:C). LcATG12 was regularly distributed in both cytoplasm and nucleus of LYCK and epithelioma papulosum cyprinid (EPC) cells. Overexpression of LcATG12 in EPC cells significantly inhibited the replication of spring viremia of carp virus (SVCV). Further studies reveled that LcATG12 could induce the occurrence of autophagy in LYCK cells. Furthermore, overexpression of LcATG12 in LYCK cells increased the expression levels of large yellow croaker type I interferons (IFNs, IFNc, IFNd, and IFNh), IFN regulatory factors (IRF3 and IRF7), and IFN-stimulated genes (PKR, Mx, and Viperin). All these data indicated that LcATG12 plays a role in the antiviral immunity possibly by inducing both autophagy and type I IFN response in large yellow croaker.


Assuntos
Doenças dos Peixes , Perciformes , Sequência de Aminoácidos , Animais , Antivirais , Proteínas de Peixes/genética , Regulação da Expressão Gênica , Imunidade , Imunidade Inata/genética , Perciformes/genética , Filogenia
20.
J Neurochem ; 159(4): 729-741, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34599505

RESUMO

Recent work has revealed that spontaneous release plays critical roles in the central nervous system, but how it is regulated remains elusive. Here, we report that synaptotagmin-11 (Syt11), a Ca2+ -independent Syt isoform associated with schizophrenia and Parkinson's disease, suppressed spontaneous release. Syt11-knockout hippocampal neurons showed an increased frequency of miniature excitatory post-synaptic currents while over-expression of Syt11 inversely decreased the frequency. Neither knockout nor over-expression of Syt11 affected the average amplitude, suggesting the pre-synaptic regulation of spontaneous neurotransmission by Syt11. Glutathione S-transferase pull-down, co-immunoprecipitation, and affinity-purification experiments demonstrated a direct interaction of Syt11 with vps10p-tail-interactor-1a (vti1a), a non-canonical SNARE protein that maintains spontaneous release. Importantly, knockdown of vti1a reversed the phenotype of Syt11 knockout, identifying vti1a as the main target of Syt11 inhibition. Domain analysis revealed that the C2A domain of Syt11 bound vti1a with high affinity. Consistently, expression of the C2A domain alone rescued the phenotype of elevated spontaneous release in Syt11-knockout neurons similar to the full-length protein. Altogether, our results suggest that Syt11 inhibits vti1a-containing vesicles during spontaneous release.


Assuntos
Proteínas Qb-SNARE/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Sinaptotagminas/farmacologia , Animais , Fenômenos Eletrofisiológicos , Potenciais Pós-Sinápticos Excitadores , Técnicas de Introdução de Genes , Hipocampo/patologia , Imunoprecipitação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/patologia , Cultura Primária de Células
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