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1.
Mol Cell ; 74(6): 1164-1174.e4, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31054975

RESUMO

Post-translational modifications of the RNA polymerase II C-terminal domain (CTD) coordinate the transcription cycle. Crosstalk between different modifications is poorly understood. Here, we show how acetylation of lysine residues at position 7 of characteristic heptad repeats (K7ac)-only found in higher eukaryotes-regulates phosphorylation of serines at position 5 (S5p), a conserved mark of polymerases initiating transcription. We identified the regulator of pre-mRNA-domain-containing (RPRD) proteins as reader proteins of K7ac. K7ac enhanced CTD peptide binding to the CTD-interacting domain (CID) of RPRD1A and RPRD1B proteins in isothermal calorimetry and molecular modeling experiments. Deacetylase inhibitors increased K7ac- and decreased S5-phosphorylated polymerases, consistent with acetylation-dependent S5 dephosphorylation by an RPRD-associated S5 phosphatase. Consistent with this model, RPRD1B knockdown increased S5p but enhanced K7ac, indicating that RPRD proteins recruit K7 deacetylases, including HDAC1. We also report autoregulatory crosstalk between K7ac and S5p via RPRD proteins and their interactions with acetyl- and phospho-eraser proteins.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas de Neoplasias/metabolismo , Isoformas de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , RNA Polimerase II/metabolismo , Acetilação , Sequência de Aminoácidos , Animais , Sítios de Ligação , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Células HEK293 , Humanos , Camundongos , Modelos Moleculares , Células NIH 3T3 , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Fosforilação , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , RNA Polimerase II/química , RNA Polimerase II/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Termodinâmica
2.
Glia ; 71(2): 415-430, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36308278

RESUMO

Oligodendrocyte precursor cells (OPCs) are uniformly distributed in the mammalian brain; however, their function is rather heterogeneous in respect to their origin, location, receptor/channel expression and age. The basic helix-loop-helix transcription factor Olig2 is expressed in all OPCs as a pivotal determinant of their differentiation. Here, we identified a subset (2%-26%) of OPCs lacking Olig2 in various brain regions including cortex, corpus callosum, CA1 and dentate gyrus. These Olig2 negative (Olig2neg ) OPCs were enriched in the juvenile brain and decreased subsequently with age, being rarely detectable in the adult brain. However, the loss of this population was not due to apoptosis or microglia-dependent phagocytosis. Unlike Olig2pos OPCs, these subset cells were rarely labeled for the mitotic marker Ki67. And, accordingly, BrdU was incorporated only by a three-day long-term labeling but not by a 2-hour short pulse, suggesting these cells do not proliferate any more but were derived from proliferating OPCs. The Olig2neg OPCs exhibited a less complex morphology than Olig2pos ones. Olig2neg OPCs preferentially remain in a precursor stage rather than differentiating into highly branched oligodendrocytes. Changing the adjacent brain environment, for example, by acute injuries or by complex motor learning tasks, stimulated the transition of Olig2pos OPCs to Olig2neg cells in the adult. Taken together, our results demonstrate that OPCs transiently suppress Olig2 upon changes of the brain activity.


Assuntos
Lesões Encefálicas , Células Precursoras de Oligodendrócitos , Animais , Células Precursoras de Oligodendrócitos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Fator de Transcrição 2 de Oligodendrócitos/metabolismo , Oligodendroglia/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular , Lesões Encefálicas/metabolismo , Mamíferos/metabolismo
3.
Pflugers Arch ; 475(9): 1035-1044, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37401986

RESUMO

In the central nervous system, oligodendrocyte precursor cells (OPCs) are recognized as the progenitors responsible for the generation of oligodendrocytes, which play a critical role in myelination. Extensive research has shed light on the mechanisms underlying OPC proliferation and differentiation into mature myelin-forming oligodendrocytes. However, recent advances in the field have revealed that OPCs have multiple functions beyond their role as progenitors, exerting control over neural circuits and brain function through distinct pathways. This review aims to provide a comprehensive understanding of OPCs by first introducing their well-established features. Subsequently, we delve into the emerging roles of OPCs in modulating brain function in both healthy and diseased states. Unraveling the cellular and molecular mechanisms by which OPCs influence brain function holds great promise for identifying novel therapeutic targets for central nervous system diseases.


Assuntos
Células Precursoras de Oligodendrócitos , Células Precursoras de Oligodendrócitos/metabolismo , Bainha de Mielina/metabolismo , Encéfalo/metabolismo , Oligodendroglia/metabolismo , Sistema Nervoso Central , Diferenciação Celular/fisiologia
4.
J Neurochem ; 164(6): 764-785, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36084044

RESUMO

The chaperon protein sigma-1 receptor (S1R) has been discovered over 40 years ago. Recent pharmacological studies using S1R exogenous ligands demonstrated a promising therapeutical potential of targeting the S1R in several neurological disorders. Although intensive in vitro studies have revealed S1Rs are mainly residing at the membrane of the endoplasmic reticulum (ER), the cell-specific in vivo expression pattern of S1Rs is still unclear, mainly because of the lack of a reliable detection method which also prevented a comprehensive functional analysis. Here, first, we identified a highly specific antibody using S1R knockout (KO) mice and established an immunohistochemical protocol involving a 1% sodium dodecyl sulphate (SDS) antigen retrieval step. Second, we characterized the S1R expression in the mouse brain and can demonstrate that the S1R is widely expressed: in principal neurons, interneurons and all glial cell types. In addition, unlike reported in previous studies, we showed that the S1R expression in astrocytes is not colocalized with the astrocytic cytoskeleton protein GFAP. Thus, our results raise concerns over previously reported S1R properties. Finally, we generated a Cre-dependent S1R conditional KO mouse (S1R flox) to study cell-type-specific functions of the S1R. As a proof of concept, we successfully ablated S1R expressions in neurons or microglia employing neuronal and microglial Cre-expressing mice, respectively. In summary, we provide powerful tools to cell-specifically detect, delete and functionally characterize S1R in vivo.


Assuntos
Neurônios , Receptores sigma , Camundongos , Animais , Neurônios/metabolismo , Neuroglia/metabolismo , Receptores sigma/genética , Astrócitos/metabolismo , Camundongos Knockout , Receptor Sigma-1
5.
Sensors (Basel) ; 23(1)2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36616777

RESUMO

Measuring motor performance in individuals with intellectual disabilities (ID) is quite challenging. The objective of this study was to compare the motor performances of individuals with ID and those with typical development (TD) during soccer dribbling through video-based behavior-coded movement assessment along with a wearable sensor. A cross-sectional research design was adopted. Adolescents with TD (N = 25) and ID (N = 29) participated in the straight-line and zigzag soccer dribbling tests. The dribbling performance was videotaped, and the footage was then analyzed with customized behavior-coding software. The coded parameters were the time for movement completion, the number of kicks, blocks, steps, the number of times the ball went out of bounds, the number of missed cones, and the trunk tilt angle. Participants with ID exhibited significantly poorer performance and demonstrated greater variances in many time and frequency domain parameters. It also revealed that participants with ID kicked with both feet while dribbling, whereas those with TD mainly used the dominant foot. The present findings demonstrated how the ID population differed from their peers in lower-extremity strategic control. The customized video-based behavior-coded approach provides an efficient and effective way to gather behavioral data and calculate performance parameter statistics in populations with intellectual disabilities.


Assuntos
Deficiência Intelectual , Futebol , Humanos , Adolescente , Estudos Transversais , Perna (Membro) , Extremidade Inferior
6.
Molecules ; 27(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36296734

RESUMO

Color is one of the important indicators affecting the quality of fermented pepper sauces, and it is closely related to carotenoid composition. This study systematically analyzed the changes in carotenoids and related physiochemical indices during the fermentation of yellow lantern pepper sauce. The CIELab color values indicated that L* and C* displayed a significant decreasing trend during fermentation. After 35 days of fermentation, the total carotenoid content significantly reduced from 3446.36 to 1556.50 µg/g DW (p < 0.05), and the degradation rate was 54.84%. Among them, the total content of carotene decreased by 56.03% during fermentation, whereas the degradation rate of xanthophylls and their esters was 44.47%. According to correlation analysis, violaxanthin myristate and lutein played a pivotal role in L*, a *, b *, chroma (C*), and yellowness index (YI). Moreover, PCA analysis indicated that lactic acid and acetic acid were the important qualities affecting the stability of pigment in fermented yellow lantern pepper sauce, which might also be the inducement of the color change. This work gives additional information concerning the discoloration of yellow lantern pepper sauce during fermentation and provides theory evidence regulating and improving the sensory qualities of yellow lantern pepper sauce.


Assuntos
Capsicum , Lactobacillus plantarum , Piper nigrum , Capsicum/química , Carotenoides/química , Lactobacillus plantarum/metabolismo , Luteína/metabolismo , Miristatos/metabolismo , Xantofilas/metabolismo , Ésteres/metabolismo , Piper nigrum/metabolismo , Ácido Láctico/metabolismo
7.
Cereb Cortex ; 30(5): 3240-3258, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31828304

RESUMO

Mammalian target of rapamycin (mTOR) signaling plays essential roles in brain development. Hyperactive mTOR is an essential pathological mechanism in autism spectrum disorder (ASD). Here, we show that tripartite motif protein 32 (TRIM32), as a maintainer of mTOR activity through promoting the proteasomal degradation of G protein signaling protein 10 (RGS10), regulates the proliferation of medial/lateral ganglionic eminence (M/LGE) progenitors. Deficiency of TRIM32 results in an impaired generation of GABAergic interneurons and autism-like behaviors in mice, concomitant with an elevated autophagy, which can be rescued by treatment embryonically with 3BDO, an mTOR activator. Transplantation of M/LGE progenitors or treatment postnatally with clonazepam, an agonist of the GABAA receptor, rescues the hyperexcitability and the autistic behaviors of TRIM32-/- mice, indicating a causal contribution of GABAergic disinhibition. Thus, the present study suggests a novel mechanism for ASD etiology in that TRIM32 deficiency-caused hypoactive mTOR, which is linked to an elevated autophagy, leads to autism-like behaviors via impairing generation of GABAergic interneurons. TRIM32-/- mouse is a novel autism model mouse.


Assuntos
Transtorno Autístico/genética , Proliferação de Células/genética , Neurônios GABAérgicos/metabolismo , Interneurônios/metabolismo , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Serina-Treonina Quinases TOR/metabolismo , Ubiquitina-Proteína Ligases/genética , Animais , Transtorno Autístico/metabolismo , Autofagia/efeitos dos fármacos , Autofagia/genética , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Clonazepam/farmacologia , Agonistas de Receptores de GABA-A/farmacologia , Neurônios GABAérgicos/efeitos dos fármacos , Interneurônios/efeitos dos fármacos , Camundongos , Camundongos Knockout , Células-Tronco Neurais/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas RGS/metabolismo
8.
Sensors (Basel) ; 20(6)2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32178312

RESUMO

Citri Reticulatae Pericarpium (CRP), has been used in China for hundreds of years as a functional food and medicine. However, some short-age CRPs are disguised as long-age CRPs by unscrupulous businessmen in order to obtain higher profits. In this paper, a rapid and nondestructive method for the classification of different-age CRPs was established using portable near infrared spectroscopy (NIRS) in diffuse reflectance mode combination with appropriate chemometric methods. The spectra of outer skin and inner capsule of CRPs at different storage ages were obtained directly without destroying the samples. Principal component analysis (PCA) with single and combined spectral pretreatment methods was used for the classification of different-age CRPs. Furthermore, the data were pretreated with the PCA method, and Fisher linear discriminant analysis (FLD) with optimized pretreatment methods was discussed for improving the accuracy of classification. Data pretreatment methods can be used to eliminate the noise and background interference. The classification accuracy of inner capsule is better than that of outer skin data. Furthermore, the best results with 100% prediction accuracy can be obtained with FLD method, even without pretreatment.


Assuntos
Medicamentos de Ervas Chinesas/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Análise Discriminante , Medicamentos de Ervas Chinesas/classificação , Análise de Componente Principal , Fatores de Tempo
9.
Br J Clin Pharmacol ; 85(11): 2614-2622, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31418902

RESUMO

AIMS: The aim of this study was to improve medication reconciliation and reduce the occurrence of duplicate prescriptions by pharmacists and physicians within 72 hours of hospital admission using an intelligent prescription system combined with the National Health Insurance PharmaCloud system to integrate the database with the medical institution computerized physician order entry (CPOE) system. METHODS: This 2-year intervention study was implemented in the geriatric ward of a hospital in Taiwan. We developed an integrated CPOE system linked with the PharmaCloud database and established an electronic platform for coordinated communication with all healthcare professionals. Patients provided written informed consent to access their PharmaCloud records. We compared the intervention effectiveness within 72 hours of admission for improvement in pharmacist medication reconciliation, increased at-home medications documentation and decreased costs from duplicated at-home prescriptions. RESULTS: The medication reconciliation rate within 72 hours of admission increased from 44.0% preintervention to 86.8% postintervention (relative risk = 1.97, 95% confidence interval [CI]: 1.69-2.31; P < .001). The monthly average of patients who brought and took home medications documented in the CPOE system during hospitalization increased by 7.54 (95% CI 5.58-20.49, P = .22). The monthly average of home medications documented increased by 102.52 (95% CI 38.44-166.60; P = .01). Savings on the monthly average prescription expenditures of at-home medication increased by US$ 2,795.52 (95% CI US$1310.41-4280.63; P < .01). CONCLUSION: Integrating medication data from PharmaCloud to the hospital's medical chart system improved pharmacist medication reconciliation, which decreased duplicated medications and reduced in-hospital medication costs.


Assuntos
Serviços de Saúde para Idosos/estatística & dados numéricos , Sistemas de Registro de Ordens Médicas/organização & administração , Reconciliação de Medicamentos/organização & administração , Admissão do Paciente/estatística & dados numéricos , Serviço de Farmácia Hospitalar/organização & administração , Idoso , Idoso de 80 Anos ou mais , Análise Custo-Benefício , Feminino , Serviços de Saúde para Idosos/economia , Humanos , Masculino , Sistemas de Registro de Ordens Médicas/economia , Programas Nacionais de Saúde/economia , Programas Nacionais de Saúde/organização & administração , Serviço de Farmácia Hospitalar/economia , Avaliação de Programas e Projetos de Saúde , Taiwan
10.
Mikrochim Acta ; 186(9): 637, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31440887

RESUMO

A method is reported for in-situ detection of the antibiotic tetracycline (TC). It is based on a combination of extraction of TC by magnetic molecularly imprinted polymers nanoparticles (MMIPs NPs) and detection by surface plasmon resonance (SPR). The TC-captured MMIPs NPs were flowed over the surface of the SPR chip that was modified with mercaptoethylamine. The SPR signal undergoes a strong increase through the use of MMIPs NPs. It increases linearly in the 5.0-100 pg·mL-1 TC concentration range, and the detection limit is as low as 1.0 pg·mL-1 (at S/N = 3). This method shows selectivity to TC compared with structurally analogues. In order to demonstrate the power of the method, it was applied to the analysis of milk spiked with TC. These results were validated by comparing them to those of an enzyme-linked immunoassay. The average recovery is in the range of 95.7-104.6%. Graphical abstract Schematic representation of a surface plasmon resonance assay for the sensitive determination of tetracycline in milk using the magnetic molecularly imprinted polymers nanoparticles that can extract tetracycline and amplify the SPR signal.

11.
Molecules ; 23(12)2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30513662

RESUMO

This study optimized the headspace solid phase microextraction (HS-SPME) conditions for the analysis of the volatile flavor compounds of Chinese south stinky tofu brine by gas chromatography-mass spectrometry (GC-MS). The optimum HS-SPME conditions established were as follows: polar column CD-WAX, white 85 µm polyella extractor, extraction temperature 60 °C, equilibrium time 20 min, extraction time 40 min. Under these conditions, a total of 63 volatile flavor compounds in five stinky tofu brines were identified. The offensive odor of the stinky tofu may be derived from some of the volatile flavor compounds such as phenol, p-cresol, 3-methylindole, indole, acetic acid, propionic acid, isobutyric acid, n-butyric acid and 3-methylbutanoic acid. The volatile flavor substances data was examined by principal component analysis (PCA) to visualize the response patterns in the feature space of principal components (PC). PCA analysis results revealed that the Chengshifu brine (STB1) and Baise jingdian brine (STB4) are similar in PC 1, 2, and 3, and the two brines have a similar flavor. Results also indicate that the Huogongdian brine (STB2) and Wangcheng brine (STB3) can be grouped in the same class as they are similar in PC 3. However, PC 1, 2, and 3 of the Luojia brine (STB5) and other brands of brine are different as is the flavor.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Sais/química , Microextração em Fase Sólida/métodos , Alimentos de Soja/análise , Compostos Orgânicos Voláteis/análise , Análise de Componente Principal , Temperatura
12.
J Hepatol ; 65(4): 700-710, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27245431

RESUMO

BACKGROUND & AIMS: Hepatitis B virus (HBV) RNA in serum has recently been linked to efficacy and prognosis of chronic hepatitis B (CHB) treatment. This study explored the nature, origin, underlying mechanisms, and potential clinical significance of serum HBV RNA. METHODS: The levels of HBV DNA and RNA were determined in the supernatant of induced HepAD38, HBV-expressing HepG2.2.15 cells and primary human hepatocytes (PHH), and in the serum of transgenic mice and CHB patients. NP-40 and proteinase K treatment, sucrose density gradient centrifugation, electron microscopy, northern blot, multiple identification PCRs and 5' rapid-amplification of cDNA ends were performed to identify the nature of serum HBV RNA. RESULTS: Although significantly lower than HBV DNA levels, abundant HBV RNA was present in the serum of CHB patients. A series of experiments demonstrated that serum HBV RNA was pregenome RNA (pgRNA) and present in virus-like particles. HBV pgRNA virion levels increased after blocking the reverse transcription activity of HBV DNA polymerase, and decreased after blocking the encapsidation of pgRNA. Furthermore, the presence of HBV pgRNA virion was associated with risk of viral rebound after discontinuation of nucleot(s)ide analogues (NAs) therapy in CHB patients. CONCLUSIONS: Serum HBV RNA was confirmed to be pgRNA present in virus-like particles. HBV pgRNA virions were produced from encapsidated particles in which the pgRNA was non- or partially reverse transcribed. Clinically, HBV pgRNA virion might be a potential biomarker for monitoring safe discontinuation of NA-therapy. LAY SUMMARY: HBV may have another virion form in which the nucleic acid is composed of RNA, not DNA. The level of HBV RNA virion in serum may be associated with risk of HBV viral rebound after withdrawal of treatment, and therefore, a potential predictive biomarker to monitor the safe discontinuation of nucleot(s)ide analogues-therapy.


Assuntos
Vírus da Hepatite B , Animais , DNA Viral , Hepatite B Crônica , Humanos , Camundongos , Octoxinol , Polietilenoglicóis , RNA Viral
13.
J Sep Sci ; 37(16): 2126-30, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24854551

RESUMO

Ginseng is a well-known traditional Chinese medicinal herb, and ginsenosides are its major active components. A method for the fast determination of ginsenosides in ginseng samples by high-performance liquid chromatography was developed and used for the quantitative analysis of four ginsenosides in three different ginseng samples. In this method, instead of time-consuming gradient elution, isocratic elution was used to speed up the analysis. Under strong isocratic elution, all the ginsenosides are eluted in 2.3 min. Although the measured signal is composed of overlapped peaks with the interferences and background, the signal of ginsenosides can be extracted by chemometric resolution. A non-negative immune algorithm was employed to obtain the chromatographic information of the target components from the data. Compared with conventional chemometric approaches, the method can perform the extraction for one-dimensional overlapping signals. The method was validated by the determination of four ginsenosides in three different ginseng samples. The recoveries of the spiked samples were in the range of 94.08-107.3%.


Assuntos
Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/análise , Ginsenosídeos/análise , Panax/química , Extratos Vegetais/análise , Algoritmos , Calibragem , Química Farmacêutica , Reprodutibilidade dos Testes
14.
J Sep Sci ; 37(13): 1585-90, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24737593

RESUMO

A method for the fast determination of the components in a complex sample by using gas chromatography with mass spectrometry was developed and used for the quantitative analysis of phthalic acid esters in environmental water. In the method, the adaptively corrected mass spectra were used to compensate for the differences between the library spectra and the measured ones in the experiment. The correction was obtained by the iterative transformation of the library spectra using iterative target transformation factor analysis, and the resolution was performed by non-negative immune algorithm using the corrected spectra. Rapid analysis of 16 phthalic acid esters in water samples was achieved using fast elution gas chromatography with mass spectrometry measurements. The results show that the mass spectra and chromatographic profiles of the phthalic acid esters can be obtained from the overlapping signal of 13 min elution, and accurate quantitative analysis can be obtained. The recoveries of the phthalic acid esters obtained by standard addition are between 90.3 and 107.4%, and the relative standard deviations obtained in repeated measurements are less than 9%.


Assuntos
Ésteres/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Ácidos Ftálicos/análise , Poluentes Químicos da Água/análise , Ésteres/isolamento & purificação , Ácidos Ftálicos/isolamento & purificação , Extração em Fase Sólida , Poluentes Químicos da Água/isolamento & purificação
15.
Food Chem ; 443: 138573, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38295561

RESUMO

An automatic, rapid and non-targeted detection method for multi-pesticides in plant-derived foods was developed by gas chromatography-mass spectrometry and chemometrics. In this method, a novel algorithm named moving window iterative target transformation factor analysis was proposed. Although there are challenges of peak overlapping and background interference, the retention time and corrected mass spectra of unknown pesticides can be automatically obtained through iteration calculation in the 'moving window' with reference to the pesticide mass spectral library. One mixed pesticide standard and nine varieties of plant-derived foods were investigated with the proposed method. By contrast, a fast temperature programme was used to shorten detection time compared to the standard temperature programme. For the mixed standard, the mass spectra and retention times of all 39 pesticides were successfully obtained from the overlapping signal. Furthermore, all spiked pesticides were successfully detected in plant-derived foods within 10 min using a fast temperature programme.


Assuntos
Resíduos de Praguicidas , Praguicidas , Praguicidas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Quimiometria , Espectrometria de Massas
16.
Front Immunol ; 15: 1425706, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39044821

RESUMO

Oligodendrocyte precursor cells (OPCs) have long been regarded as progenitors of oligodendrocytes, yet recent advances have illuminated their multifaceted nature including their emerging immune functions. This review seeks to shed light on the immune functions exhibited by OPCs, spanning from phagocytosis to immune modulation and direct engagement with immune cells across various pathological scenarios. Comprehensive understanding of the immune functions of OPCs alongside their other roles will pave the way for targeted therapies in neurological disorders.


Assuntos
Células Precursoras de Oligodendrócitos , Humanos , Células Precursoras de Oligodendrócitos/imunologia , Animais , Fagocitose/imunologia , Oligodendroglia/imunologia , Diferenciação Celular/imunologia , Imunomodulação
17.
Nat Commun ; 15(1): 6340, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39068155

RESUMO

Molecular pathways mediating systemic inflammation entering the brain parenchyma to induce sepsis-associated encephalopathy (SAE) remain elusive. Here, we report that in mice during the first 6 hours of peripheral lipopolysaccharide (LPS)-evoked systemic inflammation (6 hpi), the plasma level of adenosine quickly increased and enhanced the tone of central extracellular adenosine which then provoked neuroinflammation by triggering early astrocyte reactivity. Specific ablation of astrocytic Gi protein-coupled A1 adenosine receptors (A1ARs) prevented this early reactivity and reduced the levels of inflammatory factors (e.g., CCL2, CCL5, and CXCL1) in astrocytes, thereby alleviating microglial reaction, ameliorating blood-brain barrier disruption, peripheral immune cell infiltration, neuronal dysfunction, and depression-like behaviour in the mice. Chemogenetic stimulation of Gi signaling in A1AR-deficent astrocytes at 2 and 4 hpi of LPS injection could restore neuroinflammation and depression-like behaviour, highlighting astrocytes rather than microglia as early drivers of neuroinflammation. Our results identify early astrocyte reactivity towards peripheral and central levels of adenosine as an important pathway driving SAE and highlight the potential of targeting A1ARs for therapeutic intervention.


Assuntos
Adenosina , Astrócitos , Lipopolissacarídeos , Camundongos Endogâmicos C57BL , Microglia , Receptor A1 de Adenosina , Encefalopatia Associada a Sepse , Animais , Astrócitos/metabolismo , Astrócitos/efeitos dos fármacos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/imunologia , Adenosina/metabolismo , Camundongos , Encefalopatia Associada a Sepse/metabolismo , Receptor A1 de Adenosina/metabolismo , Masculino , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Modelos Animais de Doenças , Sepse/imunologia , Sepse/complicações , Doenças Neuroinflamatórias/imunologia , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/imunologia , Encéfalo/efeitos dos fármacos , Camundongos Knockout , Inflamação , Transdução de Sinais/efeitos dos fármacos
18.
Dev Cell ; 58(13): 1153-1169.e5, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37220747

RESUMO

Acute brain injuries evoke various response cascades directing the formation of the glial scar. Here, we report that acute lesions associated with hemorrhagic injuries trigger a re-programming of oligodendrocytes. Single-cell RNA sequencing highlighted a subpopulation of oligodendrocytes activating astroglial genes after acute brain injuries. By using PLP-DsRed1/GFAP-EGFP and PLP-EGFPmem/GFAP-mRFP1 transgenic mice, we visualized this population of oligodendrocytes that we termed AO cells based on their concomitant activity of astro- and oligodendroglial genes. By fate mapping using PLP- and GFAP-split Cre complementation and repeated chronic in vivo imaging with two-photon laser-scanning microscopy, we observed the conversion of oligodendrocytes into astrocytes via the AO cell stage. Such conversion was promoted by local injection of IL-6 and was diminished by IL-6 receptor-neutralizing antibody as well as by inhibiting microglial activation with minocycline. In summary, our findings highlight the plastic potential of oligodendrocytes in acute brain trauma due to microglia-derived IL-6.


Assuntos
Astrócitos , Lesões Encefálicas , Camundongos , Animais , Interleucina-6 , Proteína Glial Fibrilar Ácida/genética , Oligodendroglia , Camundongos Transgênicos
19.
Anal Methods ; 14(2): 114-124, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34913444

RESUMO

There has been no study on using near-infrared spectroscopy (NIRS) to predict the hotness of fresh pepper. This study is aimed at developing a non-destructive and accurate method for determining the hotness of fresh peppers using portable NIRS and the variable selection strategy. Spectra from different locations on samples were obtained non-destructively with a single scan. Quantitative models were established using partial least squares (PLS) with a variable selection method or fusion method. The results showed that near-stalk was the best spectral acquisition location for quantitative analysis. The variable selection strategy allows the selection of targeted characteristic variables and improves the results. A fusion method, namely variable adaptive boosting partial least squares (VABPLS), was selected for optimal prediction of the performance. In the optimized model, the root mean square errors of prediction for the validation set (RMSEPvs) of capsaicin, dihydrocapsaicin and pungency degree were 0.295, 0.143 and 47.770, respectively, while the root mean square errors of prediction for the prediction set (RMSEPps) collected one month later were 0.273, 0.346 and 75.524, respectively.


Assuntos
Capsicum , Análise de Alimentos/métodos , Espectroscopia de Luz Próxima ao Infravermelho , Análise dos Mínimos Quadrados , Espectroscopia de Luz Próxima ao Infravermelho/métodos
20.
Food Chem ; 386: 132792, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35367797

RESUMO

An adsorbent-magnetic molecularly imprinted polymers nanoparticles (MMIPs NPs) were synthesized for the extraction of 6-benzylaminopurine (6-BA) using Fe3O4 as magnetic core. The MIPs were prepared with methacrylic acid and sodium p-styrene sulfonate as bifunctional monomers. The adsorbents were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffractometer, thermogravimetric analysis and vibrating sample magnetometer. The adsorption properties were evaluated by static, kinetic and selective adsorption experiments. The MMIPs NPs exhibit a high adsorption capacity (37.63 mg g-1) and favorable imprinting factor (2.88) toward 6-BA. The chromatogram of 6-BA extraction using the MMIPs NPs as the adsorbent demonstrates that the matrix interference has been minimized. More importantly, MMIPs NPs can be applied to extracting 6-BA from mung bean sprout and cucumber with satisfactory recoveries (91.14-104.52%), and can be reused for at least five times. This work provides a new strategy to efficiently extract 6-BA from vegetables.


Assuntos
Nanopartículas de Magnetita , Impressão Molecular , Nanopartículas , Adsorção , Compostos de Benzil , Fenômenos Magnéticos , Nanopartículas de Magnetita/química , Impressão Molecular/métodos , Polímeros Molecularmente Impressos , Nanopartículas/química , Polímeros/química , Purinas , Verduras
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