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1.
J Am Chem Soc ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38598684

RESUMEN

Cross-coupling reactions represent an indispensable tool in chemical synthesis. An intriguing challenge in this field is to achieve selective cross-coupling between two precursors with similar reactivity or, to the limit, the identical molecules. Here we report an unexpected dehydrobrominative cross-coupling between 1,3,5-tris(2-bromophenyl)benzene molecules on silver surfaces. Using scanning tunneling microscopy, we examine the reaction process at the single-molecular level, quantify the selectivity of the dehydrobrominative cross-coupling, and reveal the modulation of selectivity by substrate lattice-related catalytic activity or molecular assembly effect. Theoretical calculations indicate that the dehydrobrominative cross-coupling proceeds via regioselective C-H bond activation of debrominated TBPB and subsequent highly selective C-C coupling of the radical-based intermediates. The reaction kinetics plays an important role in the selectivity for the cross-coupling. This work not only expands the toolbox for chemical synthesis but also provides important mechanistic insights into the selectivity of coupling reactions on the surface.

2.
Small ; : e2405174, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39072996

RESUMEN

Two-dimensional (2D) van der Waals heterostructures endow individual 2D material with the novel functional structures, intriguing compositions, and fantastic interfaces, which efficiently provide a feasible route to overcome the intrinsic limitations of single 2D components and embrace the distinct features of different materials. However, the construction of 2D heterostructures with uniform heterointerfaces still poses significant challenges. Herein, a universal in-situ interfacial growth strategy is designed to controllably prepare a series of MXene-based tin selenides/sulfides with 2D van der Waals homogeneous heterostructures. Molten salt etching by-products that are usually recognized as undesirable impurities, are reasonably utilized by us to efficiently transform into different 2D nanostructures via in-situ interfacial growth. The obtained MXene-based 2D heterostructures present sandwiched structures and lamellar interlacing networks with uniform heterointerfaces, which demonstrate the efficient conversion from 3D composite to 2D heterostructures. Such 2D heterostructures significantly enhance charge transfer efficiency, chemical reversibility, and overall structural stability in the electrochemical process. Taking 2D-SnSe2/MXene anode as a representative, it delivers outstanding lithium storage performance with large reversible capacities and ultrahigh capacity retention of over 97% after numerous cycles at 0.2, 1.0, and 10.0 A g-1 current density, which suggests its tremendous application potential in lithium-ion batteries.

3.
Exp Eye Res ; 248: 110072, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39241859

RESUMEN

The study aims to investigate the effects and potential mechanisms of lncRNA-MM2P on retinal neovascularization in a mouse model of oxygen-induced retinopathy (OIR). The OIR model was established in C57BL/6J mice. RAW264.7 cell line and bone marrow-derived macrophages (BMDMs) from mice were used for in vitro studies. RT-qPCR was used to analyze the expressions of lncRNA and mRNAs. The protein expression levels were determined by western blotting. The size of avascular areas and neovascular tufts were assessed based on isolectin B4 immunofluorescence staining images. The human retinal endothelial cells (HRECs) were used to evaluate the proliferation, migration, and tube formation of endothelial cells. The expression of lncRNA-MM2P was significantly upregulated from P17 to P25 in OIR retinas. Knockdown of lncRNA-MM2P levels in vivo led to a significant reduction in the neovascular tufts and avascular areas in the retinas of OIR mice. Knockdown of lncRNA-MM2P levels in vitro suppressed the expression of M2 markers in macrophages. Moreover, we found a significant inhibition of avascular areas and neovascular tufts in OIR mice injected intravitreally with M2 macrophages treated by shRNA-MM2P. The cellular functions of proliferation, migration, and tube formation were significantly attenuated in HRECs cultured with a supernatant of shRNA-MM2P-treated M2 macrophages. Our results indicate that lncRNA-MM2P regulates retinal neovascularization by inducing M2 polarization of macrophages in OIR mice. Therefore, lncRNA-MM2P may be a potential molecular target for immunoregulation of retinal neovascularization.

4.
J Environ Manage ; 366: 121864, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39018837

RESUMEN

This research aimed to design an integrated aerobic-anaerobic reactor with dynamic aeration that was automatically regulated based on real-time oxygen concentration and investigate the aerobic pretreatment and subsequent dry co-anaerobic digestion (co-AD) characteristics of highly solids-loaded corn stover and swine manure in terms of temperature rise, physiochemical characteristics, and methane production. The high-temperature feedstocks from the aerobic pretreatment phase rapidly entered the AD phase without transportation and effectively improved the start-up and methane production of the co-AD. Oxygen concentration range, aeration rate, and pretreatment time affected the cumulative aeration time, temperature rise, and organic matter removal interactively during aerobic pretreatment, and a low aeration rate was relatively preferable. Although the lignocellulose removal increased with the increase in pretreatment duration, the maximal lignin elimination efficiency only reached 1.30%. The inoculum injection in the transition phase from aerobic pretreatment to co-AD and the leachate reflux during co-AD were also critical for producing methane steadily apart from aerobic pretreatment. The cold air weakened the temperature rise of aerobic pretreatment, and the low-temperature leachate reduced the methane production in the co-AD process. An oxygen concentration range of 13%-17%, aeration rate of 0.10 m3/(min·m3), pretreatment time of 84 h, inoculum loading of 40%, leachate refluxing thrice per day, and double-layer inoculation were optimum for improving the integrated aerobic-anaerobic digestion system's ability to resist low temperatures and achieving high methane production. The maximal cumulative and volatile solids (VS) methane yields of corn stover and swine manure reached 444.58 L and 266.30 L/kg VS.


Asunto(s)
Estiércol , Metano , Temperatura , Zea mays , Zea mays/metabolismo , Animales , Metano/metabolismo , Porcinos , Anaerobiosis , Reactores Biológicos , Aerobiosis , Lignina
5.
J Proteome Res ; 22(5): 1483-1491, 2023 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-37014956

RESUMEN

A major challenge in reducing the death rate of colorectal cancer is to screen patients using low-invasive testing. A blood test shows a high compliance rate with reduced invasiveness. In this work, a multiplex isobaric tag labeling strategy coupled with mass spectrometry is adopted to relatively quantify primary and secondary amine-containing metabolites in serum for the discovery of metabolite level changes of colorectal cancer. Serum samples from patients at different risk statuses and colorectal cancer growth statuses are studied. Metabolite identification is based on accurate mass matching and/or retention time of labeled metabolite standards. We quantify 40 metabolites across all the serum samples, including 18 metabolites validated with standards. We find significantly decreased levels of threonine and asparagine in the patients with growing adenomas or high-risk adenomas (p < 0.05). Glutamine levels decrease in patients with adenomas of unknown growth status or high-risk adenomas. In contrast, arginine levels are elevated in patients with low-risk adenoma. Receiver operating characteristic analysis shows high sensitivity and specificity of these metabolites for detecting growing adenomas. Based on these results, we conclude that a few metabolites identified here might contribute to distinguishing colorectal patients with growing adenomas from normal individuals and patients with unknown growth status of adenomas.


Asunto(s)
Adenoma , Neoplasias Colorrectales , Humanos , Espectrometría de Masas , Curva ROC , Aminas/análisis , Adenoma/metabolismo , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/metabolismo
6.
Anal Chem ; 95(48): 17637-17645, 2023 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-37982459

RESUMEN

Glycans are vital biomolecules with diverse functions in biological processes. Mass spectrometry (MS) has become the most widely employed technology for glycomics studies. However, in the traditional data-dependent acquisition mode, only a subset of the abundant ions during MS1 scans are isolated and fragmented in subsequent MS2 events, which reduces reproducibility and prevents the measurement of low-abundance glycan species. Here, we reported a new method termed 6-plex mdSUGAR isobaric-labeling guide fingerprint embedding (MAGNI), to achieve multiplexed, quantitative, and targeted glycan analysis. The glycan peak signature was embedded by a triplicate-labeling strategy with a 6-plex mdSUGAR tag, and using ultrahigh-resolution mass spectrometers, the low-abundance glycans that carry the mass fingerprints can be recognized on the MS1 spectra through an in-house developed software tool, MAGNIFinder. These embedded unique fingerprints can guide the selection and fragmentation of targeted precursor ions and further provide rich information on glycan structures. Quantitative analysis of two standard glycoproteins demonstrated the accuracy and precision of MAGNI. Using this approach, we identified 304 N-glycans in two ovarian cancer cell lines. Among them, 65 unique N-glycans were found differentially expressed, which indicates a distinct glycosylation pattern for each cell line. Remarkably, 31 N-glycans can be quantified in only 1 × 103 cells, demonstrating the high sensitivity of our method. Taken together, our MAGNI method offers a useful tool for low-abundance N-glycan characterization and is capable of determining small quantitative differences in N-glycan profiling. Therefore, it will be beneficial to the field of glycobiology and will expand our understanding of glycosylation.


Asunto(s)
Glicómica , Espectrometría de Masas en Tándem , Femenino , Humanos , Espectrometría de Masas en Tándem/métodos , Glicómica/métodos , Reproducibilidad de los Resultados , Polisacáridos/química , Iones
7.
Anal Chem ; 95(50): 18504-18513, 2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-38033201

RESUMEN

Amino acids (AAs) in the d-form are involved in multiple pivotal neurological processes, although their l-enantiomers are most commonly found. Mass spectrometry-based analysis of low-abundance d-AAs has been hindered by challenging enantiomeric separation from l-AAs, low sensitivity for detection, and lack of suitable internal standards for accurate quantification. To address these critical gaps, N,N-dimethyl-l-leucine (l-DiLeu) tags are first validated as novel chiral derivatization reagents for chromatographic separation of 20 pairs of d/l-AAs, allowing the construction of a 4-plex isobaric labeling strategy for enantiomer-resolved quantification through single step tagging. Additionally, the creative design of N,N-dimethyl-d-leucine (d-DiLeu) reagents offers an alternative approach to generate analytically equivalent internal references of d-AAs using d-DiLeu-labeled l-AAs. By labeling cost-effective l-AA standards using paired d- and l-DiLeu, this approach not only enables absolute quantitation of both d-AAs and l-AAs from complex biological matrices with enhanced precision but also significantly boosts the combined signal intensities from all isobaric channels, greatly improving the detection and quantitation of low-abundance AAs, particularly d-AAs. We term this quantitative strategy CHRISTMAS, which stands for chiral pair isobaric labeling strategy for multiplexed absolute quantitation. Leveraging the ion mobility collision cross section (CCS) alignment, interferences from coeluting isomers/isobars are effectively filtered out to provide improved quantitative accuracy. From wild-type and Alzheimer's disease (AD) mouse brains, we successfully quantified 20 l-AAs and 5 d-AAs. The significant presence and differential trends of certain d-AAs compared to those of their l-counterparts provide valuable insights into the involvement of d-AAs in aging, AD progression, and neurodegeneration.


Asunto(s)
Aminoácidos , Proteómica , Animales , Ratones , Aminoácidos/análisis , Proteómica/métodos , Leucina/química , Aminas , Cromatografía Liquida/métodos
8.
Exp Eye Res ; 232: 109518, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37257714

RESUMEN

The aim of the study is to reveal the expression profiling and clinical significance of peripheral blood mononuclear cell (PBMC) tRNA-derived small RNAs (tsRNAs) and microRNAs (miRNAs) of premature infants with treatment-requiring retinopathy of prematurity (ROP). Significantly altered tsRNAs and miRNAs were screened using small RNA sequencing. RT-qPCR was used to verify the altered RNAs identified by small RNA transcriptomics. The target genes, their enriched functions, and possibly involved signaling pathways were identified by bioinformatics analyses. According to the small RNA sequencing, 125 tsRNAs and 205 miRNAs were significantly altered in PBMCs obtained from infants with treatment-requiring ROP compared with the premature controls without retinopathy. We preliminarily validated the significant alterations of 6 tsRNAs and 9 miRNAs. The target genes for those tsRNAs were enriched for cellular macromolecule metabolic process, intracellular anatomical structure, transcription regulatory region nucleic acid binding, and Th17 cell differentiation; those of the altered miRNAs were enriched for the developmental process, cell junction, DNA-binding transcription activator activity, and FoxO signaling pathway. By verification with the extended sample size, we identified tsRNAs and miRNAs that could be potential biomarkers with clinical values. The study recognized the alterations and clinical significance of changed tsRNA/miRNA profiles in PBMCs from premature infants with ROP. These significantly altered tsRNAs and miRNAs might be useful as potential diagnostic biomarkers and molecular targets for treatment-requiring ROP.


Asunto(s)
MicroARNs , Retinopatía de la Prematuridad , Recién Nacido , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Leucocitos Mononucleares/metabolismo , Retinopatía de la Prematuridad/diagnóstico , Retinopatía de la Prematuridad/genética , Retinopatía de la Prematuridad/metabolismo , Relevancia Clínica , Biomarcadores/metabolismo
9.
Int J Med Sci ; 20(2): 254-261, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36794165

RESUMEN

Ischemia-induced pathological neovascularization in the retina is a leading cause of blindness in various age groups. The purpose of the current study was to identify the involvement of circular RNAs (circRNAs) methylated by N6-methyladenosine (m6A), and predict their potential roles in oxygen-induced retinopathy (OIR) in mice. Methylation assessment via microarray analysis indicated that 88 circRNAs were differentially modified by m6A methylation, including 56 hyper-methylated circRNAs and 32 hypo-methylated circRNAs. Gene ontology enrichment analysis predicted that the enriched host genes of the hyper-methylated circRNAs were involved in cellular process, cellular anatomical entity, and protein binding. Host genes of the hypo-methylated circRNAs were enriched in the regulation of cellular biosynthetic process, the nucleus, and binding. According to the Kyoto Encyclopedia of Genes and Genomes analysis, those host genes were involved in the pathways of selenocompound metabolism, salivary secretion, and lysine degradation. MeRIP-qPCR verified significant alterations in m6A methylation levels of mmu_circRNA_33363, mmu_circRNA_002816, and mmu_circRNA_009692. In conclusion, the study revealed the m6A modification alterations in OIR retinas, and the findings above shed light on the potential roles of m6A methylation in circRNA regulatory functions in the pathogenesis of ischemia-induced pathological retinal neovascularization.


Asunto(s)
ARN Circular , Neovascularización Retiniana , Animales , Ratones , ARN Circular/genética , ARN Circular/metabolismo , ARN/genética , ARN/metabolismo , Neovascularización Retiniana/genética , Perfilación de la Expresión Génica , Isquemia/complicaciones , Isquemia/genética
10.
Anal Chem ; 94(34): 11773-11782, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-35960654

RESUMEN

Intact glycopeptide analysis has been of great interest because it can elucidate glycosylation site information and glycan structural composition at the same time. However, mass spectrometry (MS)-based glycoproteomic analysis is hindered by the low abundance and poor ionization efficiency of glycopeptides. Relatively large amounts of starting materials are needed for the enrichment, which makes the identification and quantification of intact glycopeptides from samples with limited quantity more challenging. To overcome these limitations, we developed an improved isobaric labeling strategy with an additional boosting channel to enhance N,N-dimethyl leucine (DiLeu) tagging-based quantitative glycoproteomic analysis, termed as Boost-DiLeu. With the integration of a one-tube sample processing workflow and high-pH fractionation, 3514 quantifiable N-glycopeptides were identified from 30 µg HeLa cell tryptic digests with reliable quantification performance. Furthermore, this strategy was applied to human cerebrospinal fluid (CSF) samples to differentiate N-glycosylation profiles between Alzheimer's disease (AD) patients and non-AD donors. The results revealed processes and pathways affected by dysregulated N-glycosylation in AD, including platelet degranulation, cell adhesion, and extracellular matrix, which highlighted the involvement of N-glycosylation aberrations in AD pathogenesis. Moreover, weighted gene coexpression network analysis (WGCNA) showed nine modules of glycopeptides, two of which were associated with the AD phenotype. Our results demonstrated the feasibility of using this strategy for in-depth glycoproteomic analysis of size-limited clinical samples. Taken together, we developed and optimized a strategy for the enhanced comprehensive quantitative intact glycopeptide analysis with DiLeu labeling, showing significant promise for identifying novel therapeutic targets or biomarkers in biological systems with a limited sample quantity.


Asunto(s)
Glicopéptidos , Glicopéptidos/análisis , Células HeLa , Humanos , Leucina/análogos & derivados , Leucina/química , Espectrometría de Masas
11.
Exp Eye Res ; 220: 109114, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35584758

RESUMEN

Retinal neovascular diseases are major causes of blindness worldwide. As a common epitranscriptomic modification of eukaryotic RNAs, N6-methyladenosine (m6A) is associated with the pathogenesis of many diseases, including angiogenesis, through the regulation of RNA metabolism and functions. The aim of this study was to identify m6A modifications of mRNAs and long noncoding RNAs (lncRNAs) and determine their potential roles in retinal neovascularization. The transcriptome-wide m6A profiles of mRNAs and lncRNAs in the retinal tissues of mice with oxygen-induced retinopathy (OIR) and controls were identified by microarray analysis of immunoprecipitated methylated RNAs. The m6A methylation levels of mRNAs and lncRNAs identified in the microarray data were validated by MeRIP-qPCR. A total of 1321 mRNAs (151 hypermethylated and 1170 hypomethylated) and 192 lncRNAs (15 hypermethylated and 177 hypomethylated) were differentially methylated with the m6A modification in OIR and control mice. Gene ontology analysis showed that hypermethylated mRNAs were enriched in the regulation of multicellular organismal process, intracellular organelle, and protein binding, while hypomethylated mRNAs were enriched in cellular metabolic process, intracellular process, and binding. Kyoto Encyclopedia of Genes and Genomes pathway analysis indicated that hypermethylated mRNAs were involved in dopaminergic synapses, glutamatergic synapse, and PI3K-Akt signaling pathway, while hypomethylated mRNAs were involved in autophagy, ubiquitin-mediated proteolysis, and spliceosome. Moreover, the altered levels of m6A methylation of ANGPT2, GNG12, ROBO4, and ENSMUST00000153785 were validated by MeRIP-qPCR. The results revealed an altered m6A epitranscriptome in OIR retinas. These methylated RNAs may act as novel modulators and targets in retinal neovascularization.


Asunto(s)
ARN Largo no Codificante , Neovascularización Retiniana , Adenosina/análogos & derivados , Animales , Perfilación de la Expresión Génica/métodos , Ratones , Oxígeno/toxicidad , Fosfatidilinositol 3-Quinasas/genética , ARN Largo no Codificante/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Superficie Celular/genética , Neovascularización Retiniana/genética
12.
J Environ Sci (China) ; 111: 229-239, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34949352

RESUMEN

Eutrophication and harmful cyanobacterial blooms threaten water resources all over the world. There is a great controversy about controlling only phosphorus or controlling both nitrogen and phosphorus in the management of lake eutrophication. The primary argument against the dual nutrients control of eutrophication is that nitrogen fixation can compensate the nitrogen deficits. Thus, it is of great necessary to study the factors that can significantly affect the nitrogen fixation. Due to the difference of climate and human influence, the water quality of different lakes (such as water temperature, N:P ratio and water residence time) is also quite different. Numerous studies have reported that the low N:P ratio can intensify the nitrogen fixation capacities. However, the effects of temperature and water residence time on the nitrogen fixation remain unclear. Thus, 30 shallows freshwater lakes in the eastern plain of China were selected to measure dissolved N2 and Ar concentrations through N2: Ar method using a membrane inlet mass spectrometer to quantify the nitrogen fixation capacities and investigate whether the temperature and water residence time have a great impact on nitrogen fixation. The results have shown that the short lake water residence time can severely inhibit the nitrogen fixation capacities through inhibiting the growth of nitrogen-fixing cyanobacteria, changing the N:P ratio and resuspending the solids from sediments. Similarly, lakes with low water temperature also have a low nitrogen fixation capacity, suggesting that controlling nitrogen in such lakes is feasible if the growth of cyanobacteria is limited by nitrogen.


Asunto(s)
Cianobacterias , Eutrofización , China , Humanos , Lagos , Nitrógeno/análisis , Fósforo/análisis , Temperatura
13.
Exp Brain Res ; 239(12): 3537-3552, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34546386

RESUMEN

Obstructive sleep apnea (OSA) is a common respiratory disorder characterized by recurrent pharyngeal collapses during sleep leading to intermittent hypoxia and sleep disruption. Cognitive challenges and high risks of cognitive impairment, including Alzheimer's disease (AD), are closely associated with OSA. Currently, continuous positive airway pressure (CPAP) is widely used in the treatment of OSA. However, whether CPAP benefits cognitive functions in patients with OSA remains elusive. Here, we identified published studies through a systematic review of PubMed, Cochrane Library, Embase, Wanfang Data, CBM, and CNKI from January 1, 1970, to July 1, 2020. 288 patients from 7 articles (one was excluded in the meta-analysis for it was a follow-up study) were included in the present study. It revealed that cognitive functions of OSA patients with mild cognitive impairment (MCI) or AD were mildly but significantly improved after CPAP treatment (SMD 0.49, 95% CI 0.11-0.86), especially long-term CPAP treatment (SMD 0.56, 95% CI 0.10-1.02, p = 0.02), as measured by Mini-Mental State Examination (MMSE) (SMD 0.49, 95%CI 0.11-0.86). However, no significant cognition benefits were detected by the Montreal Cognitive Assessment (SMD 0.43, 95% CI 0.85-1.72). In terms of heterogeneity, cognitive improvements by CPAP were detectable on OSA patients either at a younger age or over longer periods of CPAP treatment. Therefore, our findings highlight the partial efficiency of CPAP treatment in cognition improvement of OSA patients with MCI or AD.


Asunto(s)
Disfunción Cognitiva , Apnea Obstructiva del Sueño , Cognición , Disfunción Cognitiva/complicaciones , Disfunción Cognitiva/terapia , Presión de las Vías Aéreas Positiva Contínua , Estudios de Seguimiento , Humanos , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/terapia
14.
Int J Equity Health ; 20(1): 192, 2021 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-34454508

RESUMEN

BACKGROUND: Research indicates the adverse impacts of perceived discrimination on health, and discrimination inflamed by the COVID-19 pandemic, a type of social exclusion, could affect the well-being of the Chinese diaspora. We analyzed the relationship and pathways of perceived discrimination's effect on health among the Chinese diaspora in the context of the pandemic to contribute to the literature on discrimination in this population under the global public health crisis. METHODS: We analyzed data from 705 individuals of Chinese descent residing in countries outside of China who participated in a cross-sectional online survey between April 22 and May 9, 2020. This study utilized a structural equation model (SEM) to evaluate both direct and indirect effects of perceived discrimination on self-rated health (SRH) and to assess the mediating roles of psychological distress (namely, anxiety and depression) and social support from family and friends. RESULTS: This online sample comprised predominantly young adults and those of relatively high socioeconomic status. This study confirmed the total and direct effect of recently perceived discrimination on SRH and found the indirect effect was mainly mediated by depression. Mediating roles of anxiety and social support on the discrimination-health relationship were found insignificant in this SEM. CONCLUSIONS: Our findings suggest discrimination negatively affected the well-being of the Chinese diaspora, and depression acted as a major mediator between the discrimination-health relationship. Therefore, interventions for reducing discrimination to preserve the well-being of the Chinese diaspora are necessary. Prompt intervention to address depression may partially relieve the disease burden caused by the surge of discrimination.


Asunto(s)
COVID-19 , Autoevaluación Diagnóstica , Emigrantes e Inmigrantes , Pandemias , Racismo , Adolescente , Adulto , Ansiedad/epidemiología , COVID-19/epidemiología , China/etnología , Estudios Transversales , Depresión/epidemiología , Emigrantes e Inmigrantes/psicología , Emigrantes e Inmigrantes/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Racismo/psicología , Apoyo Social , Encuestas y Cuestionarios , Adulto Joven
15.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 31(2): 262-6, 2014 Apr.
Artículo en Zh | MEDLINE | ID: mdl-25039124

RESUMEN

Although a great number of studies have investigated the changes of resting-state functional connectivity (rsFC) in patients with mental disorders, such as depression and schizophrenia etc, little is known how stable the changes are, and whether temporal sad or happy mood can modulate the intrinsic rsFC. In our experiments, happy and sad video clips were used to induce temporally happy and sad mood states in 20 healthy young adults. We collected functional magnetic resonance imaging (fMRI) data while participants were watching happy or sad video clips, which were administrated in two consecutive days. Seed-based functional connectivity analyses were conducted using the anterior cingulate cortex (ACC), dorsolateral prefrontal cortex (DLPFC), and amygdala as seeds to investigate neural network related to executive function, attention, and emotion. We also investigated the association of the rsFC changes with emotional arousability level to understand individual differences. There is significantly stronger functional connectivity between the left DLPFC and posterior cingulate cortex (PCC) under sad mood than that under happy mood. The increased connectivity strength was positively correlated with subjects' emotional arousability. The increased positive correlation between the left DLPFC and PCC under sad relative to happy mood might reflect an increased processing of negative emotion-relevant stimuli. The easier one was induced by strong negative emotion (higher emotional arousability), the greater the left DLPFC-PCC connectivity was indicated, the greater the instability of the intrinsic rsFC was shown.


Asunto(s)
Afecto , Amígdala del Cerebelo/fisiología , Giro del Cíngulo/fisiología , Corteza Prefrontal/fisiología , Adulto , Atención , Humanos , Imagen por Resonancia Magnética , Adulto Joven
16.
ACS Meas Sci Au ; 4(4): 315-337, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39184361

RESUMEN

Recent advancements in mass spectrometry (MS) have revolutionized quantitative proteomics, with multiplex isotope labeling emerging as a key strategy for enhancing accuracy, precision, and throughput. This tutorial review offers a comprehensive overview of multiplex isotope labeling techniques, including precursor-based, mass defect-based, reporter ion-based, and hybrid labeling methods. It details their fundamental principles, advantages, and inherent limitations along with strategies to mitigate the limitation of ratio-distortion. This review will also cover the applications and latest progress in these labeling techniques across various domains, including cancer biomarker discovery, neuroproteomics, post-translational modification analysis, cross-linking MS, and single-cell proteomics. This Review aims to provide guidance for researchers on selecting appropriate methods for their specific goals while also highlighting the potential future directions in this rapidly evolving field.

17.
Anal Chim Acta ; 1318: 342905, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39067909

RESUMEN

BACKGROUND: Fatty acids (FAs) are essential cellular components and play important roles in various biological processes. Importantly, FAs produced by microorganisms from renewable sugars are considered sustainable substrates for biodiesels and oleochemicals. Their complex structures and diverse functional roles in biochemical processes necessitate the development of efficient and accurate methods for their quantitative analysis. RESULTS: Here, we developed a novel method for relative quantification of FAs by combining 12-plex isobaric N,N-dimethyl leucine-derivatized ethylenediamine (DiLeuEN) labeling and microchip capillary electrophoresis-mass spectrometry (CE-MS). This method enables simultaneous quantification of 12 samples in a single MS analysis. DiLeuEN labeling introduced tertiary amine center structure into FAs, which makes them compatible with the positive mode separation of commercial microchip CE systems and further improves the sensitivity. The CE separation parameters were optimized, and the quantification accuracy was assessed using FA standards. Microchip CE-MS detection exhibited high sensitivity with a femtomole level detection limit and a total analysis time within 8 min. Finally, the applicability of our method to complex biological samples was demonstrated by analyzing FAs produced by four industrially relevant yeast strains (Saccharomyces cerevisiae, Yarrowia lipolytica YB-432, Yarrowia lipolytica Po1f and Rhodotorula glutinis). The analysis time for each sample is less than 1 min. SIGNIFICANCE: This work addresses the current challenges in the field by introducing a method that combines microchip-based capillary electrophoresis separation with multiplex isobaric labeling. Our method not only offers remarkable sensitivity and rapid analysis speed but also the capability to quantify fatty acids across multiple samples simultaneously, which holds significant potential for extensive application in FA quantitative studies in diverse research areas, promising an enhanced understanding of FA functions and mechanisms.


Asunto(s)
Electroforesis por Microchip , Ácidos Grasos , Espectrometría de Masas , Ácidos Grasos/análisis , Ácidos Grasos/química , Espectrometría de Masas/métodos , Electroforesis por Microchip/métodos , Ensayos Analíticos de Alto Rendimiento , Yarrowia/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/química , Electroforesis Capilar/métodos
18.
Environ Technol ; : 1-10, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38820584

RESUMEN

The conventional aeration method is compulsorily continuous ventilation or aeration at equal intervals, and a uniform aeration rate does not vary during composting. A dynamic on-demand aeration approach based on the diverse oxygen consumption of microorganisms at different composting stages could solve the problems of insufficient oxygen supply or excessive aeration. This study aims to design an aerobic composting system with dynamic aeration, investigate the effects of dynamic aeration on the temperature rise and physicochemical characteristics during the aerobic composting of corn straw and pig manure, and optimise the control parameters of oxygen concentration. Higher temperatures and longer high-temperature durations were achieved under dynamic aeration, thereby accelerating the decomposition of organic compounds. Dynamic aeration effectively reduced the aeration frequency, the convective latent heat and moisture losses, and the power consumption in the middle and later stages of composting. The dynamic aeration regulated according to the oxygen concentration of 14%-17% in the exhaust was optimum. Under the optimal conditions, the period above 50 ℃ lasted 8.5 days, and the highest temperature, organic matter removal, and seed germination index reached 65.82 ℃, 37.59%, and 74.59%, respectively. The power consumption was decreased by 33.58% compared to the traditional intermittent aeration. Dynamic aeration would be a competitive approach for improving aerobic composting characteristics and reducing the power consumption and the hot exhaust gas emissions, especially in the cooling maturation stage, which was of great significance for realising the low-cost production of composting at scale and promoting the blossom of the organic fertiliser industry.

19.
Heliyon ; 10(1): e23668, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38192819

RESUMEN

N6-methyladenosine (m6A) modification, as the most common modification method in eukaryotes, is widely involved in numerous physiological and pathological processes, such as embryonic development, malignancy, immune regulation, and premature aging. Under pathological conditions of ocular diseases, changes in m6A modification and its metabolism can be detected in aqueous and vitreous humor. At the same time, an increasing number of studies showed that m6A modification is involved in the normal development of eye structures and the occurrence and progress of many ophthalmic diseases, especially ocular neovascular diseases, such as diabetic retinopathy, age-related macular degeneration, and melanoma. In this review, we summarized the latest progress regarding m6A modification in ophthalmic diseases, changes in m6A modification-related enzymes in various pathological states and their upstream and downstream regulatory networks, provided new prospects for m6A modification in ophthalmic diseases and new ideas for clinical diagnosis and treatment.

20.
Transl Vis Sci Technol ; 13(8): 32, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39167377

RESUMEN

Purpose: This study aimed to reveal the altered expressions of transfer RNA (tRNA)-derived small RNAs (tsRNAs) in peripheral blood mononuclear cells and identify potential diagnostic biomarkers for nonproliferative diabetic retinopathy (NPDR) from patients with type 2 diabetes mellitus. Methods: Fifty-three patients diagnosed with type 2 diabetes mellitus were enrolled, including 25 patients with NPDR and 28 patients without diabetic retinopathy (DR) as the control group. A small RNA microarray was performed to screen the differentially expressed tsRNAs. Reverse transcriptase quantitative polymerase chain reaction was used to validate the significantly altered tsRNAs in a screening cohort and a verification cohort. The target genes, their enriched functions, and signaling pathways were predicted by bioinformatics analyses. Results: In total, 668 upregulated and 485 downregulated tsRNAs were found in the NPDR group by microarray. Eight tsRNAs were validated preliminarily to be altered significantly by reverse transcriptase quantitative polymerase chain reaction, and their target genes were enriched in cellular macromolecule metabolic process and ubiquitin-mediated proteolysis. The verification experiments confirmed the increased levels of 5'tiRNA-35-PheGAA-8, tRF3-28-PheGAA-1, and tRF3b-PheGAA-6, and the decreased levels of mt-tRF3-19-ArgTCG, mt-tRF3-20-ArgTCG, and mt-tRF3-21-ArgTCG in patients with NPDR, which may serve as potential biomarkers with clinical significance. Conclusions: The study recognized the tsRNA expression changes in peripheral blood mononuclear cells from patients with NPDR and discovered potential diagnostic biomarkers that hold clinical significance. Translational Relevance: The significantly altered tsRNAs identified in the study may serve as potential diagnostic biomarkers for patients with NPDR as well as possible molecular targets of the occurrence and development of DR.


Asunto(s)
Biomarcadores , Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Leucocitos Mononucleares , ARN de Transferencia , Humanos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Masculino , Femenino , Leucocitos Mononucleares/metabolismo , Persona de Mediana Edad , Retinopatía Diabética/genética , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/sangre , Retinopatía Diabética/metabolismo , Biomarcadores/sangre , Biomarcadores/metabolismo , ARN de Transferencia/genética , Anciano , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Regulación de la Expresión Génica
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