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1.
Appl Opt ; 60(7): 2100-2108, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33690304

RESUMEN

Intelligent photonic circuits (IPCs) tuned with an appropriate phase-shift vector could enable a photonic intelligent matrix possibly implemented in multiple neural layers for a task-oriented topologies. A photonic Mach-Zehnder Interferometer (MZI) is a fundamental photonic component in IPCs, whose matrix representation could be broadcasted into an arbitrary matrix that is equipped with an optimized phase-shift vector. The initialized MZIs' phases are tentatively probed between analytical elements and a digital weight matrix that is learned from samples with efficient compatible learning for complex-valued neural networks. Nonlinear least squares is utilized to formulate a phase determination system to refine the optimal phase-shift solutions. The robustness of phase determination system for photonic neural networks is discussed in detail. For a preliminary implementation, a basic 4×4 intelligent photonic neural network is utilized to verify the proof of concept on phase-shift determination in IPC through numerical experiments.

2.
Anal Chem ; 92(2): 2043-2051, 2020 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-31894964

RESUMEN

Identification of metabolites at the trace level in complex samples is still one of the major challenges in untargeted metabolomics. One formula in the metabolomic database is always corresponding to more than one candidate, which increases the difficulty and cost in the subsequent process of standard compound matching. In this study, we developed an effective method for amine metabolite identification by hydrogen-deuterium scrambling (HDS) based on chemical isotope labeling coupled with liquid chromatography-mass spectrometry (HDS-CIL-LC-MS). After d4-4-(N,N-dimethylamino)phenyl isothiocyanate (d4-DMAP) labeling, the labeled amine metabolites can produce HDS under collision-induced dissociation (CID). The HDS can effectively reflect the number of labile hydrogen atoms in amine metabolites and thus distinguish amine isomers with different functional groups. The developed HDS-CIL-LC-MS method was applied to the determination of amine metabolites in mice feces, in which the amine candidates obtained by the database based on chemical formula searching were reduced by 64% on average, which greatly reduces the cost of standard compound matching. Taken together, the developed HDS-CIL-LC-MS analysis was demonstrated to be a promising method for untargeted metabolomics and a novel strategy for deciphering tandem mass spectrometry (MS2) spectra.


Asunto(s)
Aminas/análisis , Aminas/metabolismo , Medición de Intercambio de Deuterio , Metabolómica , Animales , Cromatografía Liquida , Heces/química , Ratones , Estructura Molecular , Espectrometría de Masas en Tándem
3.
Anal Chem ; 90(14): 8412-8420, 2018 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-29924596

RESUMEN

Chemical labeling (CL) in combination with liquid chromatography-mass spectrometry (LC-MS) analysis has been demonstrated to be a promising technology in metabolomic analysis. However, identification of chemically labeled metabolites remains to be challenging. Retention time (RT) is one of the most important parameters for the identification of metabolites, but it could vary greatly in LC-MS analysis. In this work, we developed a chemical labeling-based HPLC retention index (CL-HPLC RI) strategy to facilitate the identification of metabolites. In this CL-HPLC RI strategy, a series of 2-dimethylaminoethylamine (DMED)-labeled fatty acids were used as calibrants to establish RIs for DMED-labeled carboxylated compounds and a series of 4-( N, N-dimethylamino)phenyl isothiocyanate (DMAP)-labeled fatty amines were used as calibrants for DMAP-labeled amine compunds. To calculate the RIs, the whole LC chromatogram was divided into 24 time intervals by 23 DMED-labeled fatty acid standards or 15 time intervals by 14 DMAP-labeled fatty amine standards. Then, we established the RIs of 854 detected DMED-labeled carboxylated metabolites and 1057 DMAP-labeled amine metabolites in fecal samples and demonstrated that RIs were highly reproducible under different elution gradients, columns, and instrument systems. Finally, we applied this strategy to the identification of metabolites in human serum. Using RIs, 267 DMED-labeled carboxylated metabolites and 273 DMAP-labeled amine metabolites in human serum matched well with the fecal metabolome database. Taken together, the developed CL-HPLC RI strategy was demonstrated to be a promising method to facilitate the identification of metabolites in metabolomic analysis.


Asunto(s)
Aminas/análisis , Cromatografía Líquida de Alta Presión/métodos , Ácidos Grasos/análisis , Heces/química , Metabolómica/métodos , Suero/química , Aminas/metabolismo , Animales , Ácidos Grasos/metabolismo , Humanos , Espectrometría de Masas/métodos , Metaboloma , Ratones , Suero/metabolismo
4.
Anal Chem ; 90(5): 3512-3520, 2018 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-29406693

RESUMEN

Gut microbiota plays important roles in the host health. The host and symbiotic gut microbiota coproduce a large number of metabolites during the metabolism of food and xenobiotics. The analysis of fecal metabolites can provide a noninvasive manner to study the outcome of the host-gut microbiota interaction. Herein, we reported the comprehensive profiling of fecal metabolome of mice by an integrated chemical isotope labeling combined with liquid chromatography-mass spectrometry (CIL-LC-MS) analysis. The metabolites are categorized into several submetabolomes based on the functional moieties (i.e., carboxyl, carbonyl, amine, and thiol) and then analysis of the individual submetabolome was performed. The combined data from the submetabolome form the metabolome with relatively high coverage. To this end, we synthesized stable isotope labeling reagents to label metabolites with different groups, including carboxyl, carbonyl, amine, and thiol groups. We detected 2302 potential metabolites, among which, 1388 could be positively or putatively identified in feces of mice. We then further confirmed 308 metabolites based on our established library of chemically labeled standards and tandem mass spectrometry analysis. With the identified metabolites in feces of mice, we established mice fecal metabolome database, which can be used to readily identify metabolites from feces of mice. Furthermore, we discovered 211 fecal metabolites exhibited significant difference between Alzheimer's disease (AD) model mice and wild type (WT) mice, which suggests the close correlation between the fecal metabolites and AD pathology and provides new potential biomarkers for the diagnosis of AD.


Asunto(s)
Heces/química , Espectrometría de Masas/métodos , Metaboloma , Metabolómica/métodos , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/metabolismo , Animales , Biomarcadores/análisis , Biomarcadores/metabolismo , Humanos , Marcaje Isotópico/métodos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos
5.
Brain ; 139(Pt 7): 1919-38, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27289302

RESUMEN

There are no treatments in clinical practice known to mitigate the neurobiological processes that convert a healthy brain into an epileptic one, a phenomenon known as epileptogenesis. Downregulation of protein phosphatase 2A, a protein that causes the hyperphosphorylation of tau, is implicated in neurodegenerative diseases commonly associated with epilepsy, such as Alzheimer's disease and traumatic brain injury. Here we used the protein phosphatase 2A activator sodium selenate to investigate the role of protein phosphatase 2A in three different rat models of epileptogenesis: amygdala kindling, post-kainic acid status epilepticus, and post-traumatic epilepsy. Protein phosphatase 2A activity was decreased, and tau phosphorylation increased, in epileptogenic brain regions in all three models. Continuous sodium selenate treatment mitigated epileptogenesis and prevented the biochemical abnormalities, effects which persisted after drug withdrawal. Our studies indicate that limbic epileptogenesis is associated with downregulation of protein phosphatase 2A and the hyperphosphorylation of tau, and that targeting this mechanism with sodium selenate is a potential anti-epileptogenic therapy.


Asunto(s)
Anticonvulsivantes/farmacología , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Epilepsia/metabolismo , Proteína Fosfatasa 2/metabolismo , Ácido Selénico/farmacología , Proteínas tau/metabolismo , Animales , Encéfalo/efectos de los fármacos , Encéfalo/fisiopatología , Lesiones Traumáticas del Encéfalo/complicaciones , Electroencefalografía , Epilepsia/inducido químicamente , Epilepsia/tratamiento farmacológico , Epilepsia/etiología , Agonistas de Aminoácidos Excitadores/farmacología , Ácido Kaínico/farmacología , Excitación Neurológica , Imagen por Resonancia Magnética , Masculino , Fosforilación , Proteína Fosfatasa 2/efectos de los fármacos , Ratas , Ratas Wistar , Proteínas tau/efectos de los fármacos
6.
Brain ; 138(Pt 5): 1297-313, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25771151

RESUMEN

Traumatic brain injury is a common and serious neurodegenerative condition that lacks a pharmaceutical intervention to improve long-term outcome. Hyperphosphorylated tau is implicated in some of the consequences of traumatic brain injury and is a potential pharmacological target. Protein phosphatase 2A is a heterotrimeric protein that regulates key signalling pathways, and protein phosphatase 2A heterotrimers consisting of the PR55 B-subunit represent the major tau phosphatase in the brain. Here we investigated whether traumatic brain injury in rats and humans would induce changes in protein phosphatase 2A and phosphorylated tau, and whether treatment with sodium selenate-a potent PR55 activator-would reduce phosphorylated tau and improve traumatic brain injury outcomes in rats. Ninety young adult male Long-Evans rats were administered either a fluid percussion injury or sham-injury. A proportion of rats were killed at 2, 24, and 72 h post-injury to assess acute changes in protein phosphatase 2A and tau. Other rats were given either sodium selenate or saline-vehicle treatment that was continuously administered via subcutaneous osmotic pump for 12 weeks. Serial magnetic resonance imaging was acquired prior to, and at 1, 4, and 12 weeks post-injury to assess evolving structural brain damage and axonal injury. Behavioural impairments were assessed at 12 weeks post-injury. The results showed that traumatic brain injury in rats acutely reduced PR55 expression and protein phosphatase 2A activity, and increased the expression of phosphorylated tau and the ratio of phosphorylated tau to total tau. Similar findings were seen in post-mortem brain samples from acute human traumatic brain injury patients, although many did not reach statistical significance. Continuous sodium selenate treatment for 12 weeks after sham or fluid percussion injury in rats increased protein phosphatase 2A activity and PR55 expression, and reduced the ratio of phosphorylated tau to total tau, attenuated brain damage, and improved behavioural outcomes in rats given a fluid percussion injury. Notably, total tau levels were decreased in rats 12 weeks after fluid percussion injury, and several other factors, including the use of anaesthetic, the length of recovery time, and that some brain injury and behavioural dysfunction still occurred in rats treated with sodium selenate must be considered in the interpretation of this study. However, taken together these data suggest protein phosphatase 2A and hyperphosphorylated tau may be involved in the neurodegenerative cascade of traumatic brain injury, and support the potential use of sodium selenate as a novel traumatic brain injury therapy.


Asunto(s)
Lesiones Encefálicas/tratamiento farmacológico , Ácido Selénico/farmacología , Proteínas tau/metabolismo , Enfermedad de Alzheimer/metabolismo , Animales , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Modelos Animales de Enfermedad , Humanos , Masculino , Fosforilación/efectos de los fármacos , Ratas Long-Evans
7.
Huan Jing Ke Xue ; 45(7): 3828-3838, 2024 Jul 08.
Artículo en Zh | MEDLINE | ID: mdl-39022931

RESUMEN

Based on a typical ozone (O3) pollution process in Jinan City from June 16 to 26, 2021, the variation characteristics of O3 and its precursor volatile organic compounds (VOCs) during different pollution periods (clean period (CP), pollution rise period (PRP), heavy pollution period (HPP), and pollution decline period (PDP)) in the urban area were analyzed. Both positive matrix factorization (PMF) and an observation-based model (OBM) were used to identify the main sources of VOCs, O3 production mechanisms, and sensitive species. The results showed that the average value of ρ(O3-8h) during the HPP period in the urban area was (246.67±11.24) µg·m-3, and ρ(O3-1h) had a peak value of 300 µg·m-3. The volume fractions of VOCs and NO2 concentration were affected by the decrease in planetary boundary layer and wind speed, which were 76.99%-145.36% and 127.78%-141.18% higher than those in the other three periods, respectively, and were the main reasons for the aggravation of O3 pollution. Alkanes, oxygenated volatile organic compounds (OVOCs), and halogenated hydrocarbons accounted for 43.81%, 20.98%, and 17.43% of VOCs in urban areas, respectively. All of them showed significant growth during the HPP period, with acetone, propane, and ethane being the top three species by volume in each stage and isopentane showing the highest growth during the HPP period. Alkene, alkanes, and aromatic hydrocarbons accounted for 40.19%, 28.06%, and 21.92% of the ozone generation potential (OFP). 1-butene, toluene, isopentane, and isoprene were the species with higher OFP. Isoprene had the highest OFP during the PRP phase, and 1-butene had the highest OFP during the HPP phase. The volume fraction of isopentane significantly increased OFP. The correlation coefficient between VOCs and CO preliminarily indicated that motor vehicle exhaust and oil and gas volatilization were the main sources of VOCs during the HPP period. Further use of PMF revealed that solvent use sources, combustion sources, motor vehicle exhaust+oil and gas volatilization sources, industrial emission sources, and plant sources were important sources of VOCs in urban areas. The contribution of motor vehicle exhaust+oil and gas volatilization sources in the HPP period to VOCs was 3.09-14.72 times higher than that in other periods. The contribution of solvent use sources to VOCs was approximately 2.50 times higher than that in the CP and PRP periods. The main sources of VOCs volume fraction increase were motor vehicle exhaust, oil and gas volatilization sources, and solvent use sources. Potential sources and concentration weight analysis found that VOCs were also affected by the transmission of VOCs to Binzhou and Dongying in the northeast direction. The OBM results indicated that the main pathway of O3 formation in urban areas was the reaction of peroxide hydroxyl radicals (HO2·ï¼‰ and methyl peroxide radicals (CH3O2·ï¼‰ with NO, and the net ozone generation rate during the HPP phase [P(O3)net] was 24×10-9 h-1. Based on the sensitivity experiment results, the alkene components of 1-butene, propylene, cis-2-butene, and ethylene were the dominant species for O3 production.

8.
ChemSusChem ; 17(14): e202301778, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38433647

RESUMEN

Photocatalysis has the advantages of practical, sustainable and environmental protection, so it plays a significant role in energy transformation and environmental utilization. CeO2 has attracted widespread attention for its unique 4 f electrons, rich defect structures, high oxygen storage capacity and great chemical stability. In this paper, we review the structure of CeO2 and the common methods for the preparation of CeO2-based composites in the first part. In particular, we highlight the co-precipitation method, template method, and sol-gel method methods. Then, in the second part, we introduce the application of CeO2-based composites in photocatalysis, including photocatalytic CO2 reduction, hydrogen production, degradation, selective organic reaction, and photocatalytic nitrogen fixation. In addition, we discuss several modification techniques to improve the photocatalytic performance of CeO2-based composites, such as elemental doping, defect engineering, constructing heterojunction and morphology regulation. Finally, the challenges faced by CeO2-based composites are analyzed and their development prospects are prospected. This review provides a systematic summary of the recent advance of CeO2-based composites in the field of photocatalysis, which can provide useful references for the rational design of efficient CeO2-based composite photocatalysts for sustainable development.

9.
Zool Res ; 45(3): 586-600, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38766743

RESUMEN

The placenta plays a crucial role in successful mammalian reproduction. Ruminant animals possess a semi-invasive placenta characterized by a highly vascularized structure formed by maternal endometrial caruncles and fetal placental cotyledons, essential for full-term fetal development. The cow placenta harbors at least two trophoblast cell populations: uninucleate (UNC) and binucleate (BNC) cells. However, the limited capacity to elucidate the transcriptomic dynamics of the placental natural environment has resulted in a poor understanding of both the molecular and cellular interactions between trophoblast cells and niches, and the molecular mechanisms governing trophoblast differentiation and functionalization. To fill this knowledge gap, we employed Stereo-seq to map spatial gene expression patterns at near single-cell resolution in the cow placenta at 90 and 130 days of gestation, attaining high-resolution, spatially resolved gene expression profiles. Based on clustering and cell marker gene expression analyses, key transcription factors, including YBX1 and NPAS2, were shown to regulate the heterogeneity of trophoblast cell subpopulations. Cell communication and trajectory analysis provided a framework for understanding cell-cell interactions and the differentiation of trophoblasts into BNCs in the placental microenvironment. Differential analysis of cell trajectories identified a set of genes involved in regulation of trophoblast differentiation. Additionally, spatial modules and co-variant genes that help shape specific tissue structures were identified. Together, these findings provide foundational insights into important biological pathways critical to the placental development and function in cows.


Asunto(s)
Perfilación de la Expresión Génica , Placenta , Placentación , Transcriptoma , Animales , Bovinos/genética , Femenino , Embarazo , Placenta/metabolismo , Trofoblastos/metabolismo
10.
Zhongguo Zhong Yao Za Zhi ; 38(11): 1816-9, 2013 Jun.
Artículo en Zh | MEDLINE | ID: mdl-24010302

RESUMEN

OBJECTIVE: To observe the effect of psoralidine in rats with ovariectomy, and preliminarily study its mechanism. METHOD: Sixty female Sprague-Dawley rats were divided into 5 groups: the sham operation group, the model group, the psoralidine low-dose group (4 mg x kg(-1)), the psoralidine high-dose group (16 mg x kg(-1)) and the Zhuangguzhitong capsule group, with 12 rats in each group. Thirteen weeks later, their blood and bone samples were collected to detect bone density, bone biochemistry, pathomorphology, serum E2 and CT. RESULT: Psoralidine could up-regulate the bone density of lumbar vertebra and thighbone of rats with ovariectomy (P < 0.05), the maximum bending strength of thighbone (P < 0.05), and serum E2 and CT (P < 0.05). CONCLUSION: Psoralidine has a good active effect on postmenopausal antiosteoporosis. Its mechanism may be related to such pathways as E2 and CT.


Asunto(s)
Benzofuranos/administración & dosificación , Cumarinas/administración & dosificación , Medicamentos Herbarios Chinos/administración & dosificación , Osteoporosis Posmenopáusica/tratamiento farmacológico , Animales , Densidad Ósea/efectos de los fármacos , Estradiol/sangre , Femenino , Humanos , Osteoporosis Posmenopáusica/sangre , Osteoporosis Posmenopáusica/fisiopatología , Ratas , Ratas Sprague-Dawley
11.
Front Immunol ; 14: 1293511, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38162651

RESUMEN

Objective: Numerous observational investigations have documented a correlation between asthma and ulcerative colitis(UC). In this Mendelian Randomization (MR) study, we utilized extensive summary data from Genome-Wide Association Studies (GWAS) to further estimate the association between adult-onset asthma and the risk of UC, and to investigate the role of Interleukin-18 (IL-18) as a potential mediator. Materials and methods: A two-step, two-sample MR study was conducted through mediation analysis. For this study, we employed a two-sample MR analysis using the inverse variance-weighted (IVW), weighted median, weighted mode, and MR-Egger regression techniques. We utilized publicly accessible summary statistics from a GWAS meta-analysis of adult-onset asthma in the UK Biobank (n=327,253; cases=26,582; controls=300,671) as the exposure factor. The outcomes were derived from GWAS data of individuals with European ancestry (n=26,405; cases=6,687; controls=19,718). GWAS data for IL-18 were obtained from individuals of European ancestry (n=9,785,222; cases=3,636; controls=9,781,586). Results: The MR analysis indicates that adult-onset asthma is associated with an increased risk of UC, with an odds ratio (OR) of 1.019 (95% CI 1.001-1.045, P=0.006). However, there is no strong evidence to suggest that UC significantly impacts the risk of adult-onset asthma. IL-18 may act as a potential mediator in the causal relationship between adult-onset asthma and UC, with a mediation proportion of 3.9% (95% CI, 0.6%-6.9%). Conclusion: In summary, our study established a causal relationship between asthma and UC, in which IL-18 contributes to a small extent. However, the primary factors underlying the influence of asthma on UC remain unclear. Future research should focus on identifying other potential mediators. In clinical practice, it is important to pay greater attention to intestinal lesions in patients with asthma.


Asunto(s)
Asma , Colitis Ulcerosa , Interleucina-18 , Adulto , Humanos , Asma/genética , Colitis Ulcerosa/genética , Estudio de Asociación del Genoma Completo , Interleucina-18/genética , Análisis de Mediación , Análisis de la Aleatorización Mendeliana
12.
Huan Jing Ke Xue ; 44(12): 6433-6440, 2023 Dec 08.
Artículo en Zh | MEDLINE | ID: mdl-38098372

RESUMEN

Meteorological conditions play a key role in the occurrence and evolution of atmospheric complex pollution. Considering the different pollution formation mechanisms of PM2.5 and O3, statistical calculation and in-depth learning methods were used to construct the PM2.5 and O3 meteorological condition indexes based on long-term pollution meteorological observation data. A research method was developed to study the meteorological characteristics and impact contribution of atmospheric complex pollution by using the meteorological condition index, and quantitative analysis of the distribution and variation of pollution excluding the influence of regional meteorological differences was also conducted. The results showed that in the summer of 2021, the pollution meteorological conditions in the key regions in central and eastern China were generally worse in the north and better in the south(index:"2+26" cities>the border area of Jiangsu, Anhui, Shandong, and Henan>the Yangtze River Delta) and the worst in June and the best in July. The "double high" pollution began to appear when the PM2.5 meteorological condition index>30 and O3 meteorological condition index>100; meanwhile, the unfavorable meteorological conditions for O3 also promoted the increase in PM2.5 concentration, resulting in the frequency of "double high" increases with the increase in O3 meteorological condition index. Compared with that during the same period last year, ρ(PM2.5) of each region decreased by 3.9 µg·m-3, 3.3 µg·m-3, and 1.4 µg·m-3 due to the contribution of the improvement in the pollution meteorological conditions, which is nearly 58.5% on average of the total decrease in PM2.5 concentration. However, the change in O3 pollution meteorological conditions was better in the north and worse in the south, and the overall deterioration in the Yangtze River Delta Region led to approximately 2.8 µg·m-3 growth for the O3 concentration. The PM2.5 and O3 concentrations after excluding the impact of meteorological differences showed different distribution characteristics from the air quality monitoring, in which the high concentrations of PM2.5 were distributed along the Bohai Sea, the inter-provincial border, and the south of the region, whereas the high concentrations of O3 were concentrated along the Taihang Mountains, around Mount Tai, and in parts of the Yangtze River Delta. The daily concentration variations in a single city during a specific pollution control period could be used as a basis for evaluating the effectiveness of local supervision and control, which will provide a reference for the dynamic supervision and daily scheduling of local control management.

13.
Huan Jing Ke Xue ; 43(6): 2906-2916, 2022 Jun 08.
Artículo en Zh | MEDLINE | ID: mdl-35686760

RESUMEN

In this study, taking the Beijing-Tianjin-Hebei region as an example, CMAQ and BETR models were constructed to carry out numerical simulation for the pyrene (Pyr) and benzo[a] pyrene (BaP) in 2014. The model results were compared and evaluated for the atmospheric transportation and transformation of PAHs. Additionally, the XGBoost model was used to identify the key atmospheric physicochemical processes and parameters that affect the environmental behavior of PAHs in the CMAQ. The results showed that the ratio of the simulated value of BETR and annual average value of CMAQ to the measured annual average value was between 1/2 and 2, and the seasonal trend of the simulated concentrations of Pyr and BaP from the CMAQ model were basically consistent with the measured values, which verified the reliability of the two types of models. At the same time, the simulated concentration of the CMAQ model averaged from 9 km grid to 27 km grid and was comparable to the BETR concentration. The results showed that the average concentrations of Pyr and BaP in the BETR model were approximately 1.59 and 1.38 times those of the CMAQ simulation concentrations, respectively, indicating that the two models had good comparability in terms of average annual concentration level and spatial distribution. The SHAP-based variable importance on the XGBoost model showed that boundary layer height was the most significant meteorological factor affecting the transportation and transformation of Pyr and BaP, accounting for 22%-35% of all factors, and sometimes even exceeded the emissions for certain cities and pollutants. The boundary layer height was significantly negatively correlated with the concentration of PAHs. Wind speed was a secondary factor affecting the concentration of PAHs and was negatively correlated with the PAHs, whereas the influence of wind direction on the concentration of PAHs varied.


Asunto(s)
Contaminantes Atmosféricos , Hidrocarburos Policíclicos Aromáticos , Contaminantes Atmosféricos/análisis , Beijing , Benzo(a)pireno , China , Monitoreo del Ambiente , Hidrocarburos Policíclicos Aromáticos/análisis , Pirenos , Reproducibilidad de los Resultados
14.
Biosens Bioelectron ; 215: 114568, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35850041

RESUMEN

Accurate and non-invasive monitoring of allograft posttransplant is essential for early detection of acute cellular rejection and determines the long-term survival of the graft. Clinically, tissue biopsy is the most effective approach for diagnosing transplant rejection. Nonetheless, the procedure is invasive and potentially triggers organ failure. This work aims to design and apply GzmB-responsive nanosensors (GBRNs) that can readily size-change in graft tissues. Subsequently, we investigate the activity of serine protease granzyme B by generating a direct colorimetric urinary readout for non-invasive detection of transplant rejection in under 1 h. In preclinical heart graft mice models of transplant rejection, GBRNs were cleaved by GzmB and excreted by the kidneys via accurate nanometre-size glomerular filtration. By exploiting the catalytic activity of ultrasmall gold nanoclusters, GBRNs urinalysis promotes ultrasensitive surveillance of rejection episodes with a receiver operator characteristic curve area under the curve of 0.896 as well as a 95% confidence interval of about 0.7701-1.000. Besides, the catalytic activity of gold nanoclusters in urine can be detected at point-of-care testing to predict the immunity responses in mice with insufficient immunosuppressive therapy. Therefore, this non-invasive, sensitive, and quantitative method is a robust and informative approach for rapid and routine monitoring of transplant allografts without invasive biopsy.


Asunto(s)
Técnicas Biosensibles , Trasplante de Riñón , Animales , Biomarcadores/orina , Oro , Rechazo de Injerto/diagnóstico , Rechazo de Injerto/orina , Trasplante de Riñón/efectos adversos , Ratones , Sistemas de Atención de Punto
15.
Mil Med Res ; 9(1): 38, 2022 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-35799293

RESUMEN

BACKGROUND: Autophagy dysfunction plays a crucial role in tau accumulation and neurodegeneration in Alzheimer's disease (AD). This study aimed to investigate whether and how the accumulating tau may in turn affect autophagy. METHODS: The primary hippocampal neurons, N2a and HEK293T cells with tau overexpression were respectively starved and treated with vinblastine to study the effects of tau on the initiating steps of autophagy, which was analysed by Student's two-tailed t-test. The rapamycin and concanamycin A were employed to inhibit the mammalian target of rapamycin kinase complex 1 (mTORC1) activity and the vacuolar H+-ATPase (v-ATPase) activity, respectively, which were analysed by One-way ANOVA with post hoc tests. The Western blotting, co-immunoprecipitation and immunofluorescence staining were conducted to gain insight into the mechanisms underlying the tau effects of mTORC1 signaling alterations, as analysed by Student's two-tailed t-test or One-way ANOVA with post hoc tests. The autophagosome formation was detected by immunofluorescence staining and transmission electron microscopy. The amino acids (AA) levels were detected by high performance liquid chromatography (HPLC). RESULTS: We observed that overexpressing human full-length wild-type tau to mimic AD-like tau accumulation induced autophagy deficits. Further studies revealed that the increased tau could bind to the prion-related domain of T cell intracellular antigen 1 (PRD-TIA1) and this association significantly increased the intercellular level of amino acids (Leucine, P = 0.0038; Glutamic acid, P = 0.0348; Alanine, P = 0.0037; Glycine, P = 0.0104), with concordant upregulation of mTORC1 activity [phosphorylated eukaryotic translation initiation factor 4E-binding protein 1 (p-4EBP1), P < 0.0001; phosphorylated 70 kDa ribosomal protein S6 kinase 1 (p-p70S6K1), P = 0.0001, phosphorylated unc-51-like autophagy-activating kinase 1 (p-ULK1), P = 0.0015] and inhibition of autophagosome formation [microtubule-associated protein light chain 3 II (LC3 II), P = 0.0073; LC3 puncta, P < 0.0001]. As expected, this tau-induced deficit of autophagosome formation in turn aggravated tau accumulation. Importantly, we also found that blocking TIA1 and tau interaction by overexpressing PRD-TIA1, downregulating the endogenous TIA1 expression by shRNA, or downregulating tau protein level by a small proteolysis targeting chimera (PROTAC) could remarkably attenuate tau-induced autophagy impairment. CONCLUSIONS: Our findings reveal that AD-like tau accumulation inhibits autophagosome formation and induces autophagy deficits by activating the TIA1/amino acid/mTORC1 pathway, and thus this work reveals new insight into tau-associated neurodegeneration and provides evidence supporting the use of new therapeutic targets for AD treatment and that of related tauopathies.


Asunto(s)
Autofagosomas , Diana Mecanicista del Complejo 1 de la Rapamicina , Antígeno Intracelular 1 de las Células T , Proteínas tau , Aminoácidos/metabolismo , Autofagosomas/metabolismo , Células HEK293 , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Antígeno Intracelular 1 de las Células T/metabolismo , Proteínas tau/metabolismo , Proteínas tau/farmacología
16.
Light Sci Appl ; 11(1): 329, 2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36414615

RESUMEN

The solar X-ray and Extreme Ultraviolet Imager (X-EUVI), developed by the Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences (CIOMP), is the first space-based solar X-ray and Extreme ultraviolet (EUV) imager of China loaded on the Fengyun-3E (FY-3E) satellite supported by the China Meteorological Administration (CMA) for solar observation. Since started work on July 11, 2021, X-EUVI has obtained many solar images. The instrument employs an innovative dual-band design to monitor a much larger temperature range on the Sun, which covers 0.6-8.0 nm in the X-ray region with six channels and 19.5 nm in the EUV region. X-EUVI has a field of view of 42', an angular resolution of 2.5″ per pixel in the EUV band and an angular resolution of 4.1″ per pixel in the X-ray band. The instrument also includes an X-ray and EUV irradiance sensor (X-EUVS) with the same bands as its imaging optics, which measures the solar irradiance and regularly calibrates the solar images. The radiometric calibration of X-EUVS on the ground has been completed, with a calibration accuracy of 12%. X-EUVI is loaded on the FY-3E satellite and rotates relative to the Sun at a uniform rate. Flat-field calibration is conducted by utilizing successive rotation solar images. The agreement between preliminarily processed X-EUVI images and SDO/AIA and Hinode/XRT images indicates that X-EUVI and the data processing algorithm operate properly and that the data from X-EUVI can be applied to the space weather forecast system of CMA and scientific investigations on solar activity.

17.
Scand J Infect Dis ; 43(8): 632-41, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21428852

RESUMEN

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) is a serious public health problem in China, and is primarily caused by either the Hantaan virus (HTNV) or Seoul virus (SEOV) strains. However, the causative hantavirus has only been definitively identified in a few HFRS cases, and detailed comparisons of patient data for the 2 strains are limited. METHODS: We conducted a 1-y prospective study in Heilongjiang Province, China. A total of 152 patients from 3 hospitals met the HFRS diagnostic criteria used in China. The diagnosis was further confirmed by specific immunoglobulin M to HTNV or SEOV. In addition, serum samples were tested for the presence of HTNV or SEOV using a reverse transcription-polymerase chain reaction (RT-PCR). Clinical manifestations and laboratory findings in patients with the 2 hantaviruses were subsequently compared. RESULTS: Eighty (61.1%) HTNV and 51 (38.9%) SEOV infections were identified. Fever and proteinuria, key to the diagnosis of HFRS, were observed in all patients. The clinical manifestations of hemorrhage and renal injury from SEOV infection were milder than those of HTNV infection. Interestingly, compared to patients with HTNV infection, patients with SEOV presented with a significantly longer febrile period, more normal white blood cell counts or even transient leukocytopenia, a higher incidence of liver injury related to disease severity, and a lower occurrence of the 5 typical phases of HFRS. The mortality was 6.3% in HTNV infections and 0% in SEOV infections. CONCLUSIONS: Clinical manifestations of SEOV infection appear to be milder and less typical than HTNV. This information may help us to improve the diagnosis of SEOV-infected patients.


Asunto(s)
Virus Hantaan/aislamiento & purificación , Fiebre Hemorrágica con Síndrome Renal/virología , Virus Seoul/aislamiento & purificación , Adolescente , Adulto , Anciano , China/epidemiología , Femenino , Genotipo , Virus Hantaan/genética , Fiebre Hemorrágica con Síndrome Renal/sangre , Fiebre Hemorrágica con Síndrome Renal/diagnóstico , Fiebre Hemorrágica con Síndrome Renal/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Virus Seoul/genética , Estadísticas no Paramétricas
18.
Huan Jing Ke Xue ; 42(7): 3127-3135, 2021 Jul 08.
Artículo en Zh | MEDLINE | ID: mdl-34212638

RESUMEN

To investigate the pollution characteristics and sources of atmospheric brown carbon (BrC) in Chongming Island, a background site of the Yangtze River Delta (YRD) region in China, PM2.5 samples collected from December 2018 to January 2019 were analyzed to determine their chemical compositions and optical properties. The results showed that the light absorption coefficient (Abs365,M) of BrC extracted by methanol at 365 nm was (5.39±3.33) M-1·m-1, which was 1.3 times of the water extracted BrC. Both increased significantly with the increase of pH values, suggesting that less acidic conditions can enhance the light absorption ability of BrC. In winter, both Abs365 and MAE365 (mass absorption efficiency) were higher in the nighttime than in the daytime. A strong linear correlation observed between Abs365 and levoglucosan (R2=0.72) indicated that many light absorbing substances in Chongming Island were derived from biomass burning emissions. During the campaign, nitro-aromatic compounds (NACs) and PAHs accounted for (1.5±1.1) ng·m-3 and (8.3±4.7) ng·m-3, respectively, contributing to 0.1% and 0.067% of the absorption of the total BrC at 365 nm, respectively. Positive matrix factorization (PMF) analysis further showed that biomass and fossil fuel combustions were the main sources of BrC in Chongming Island in winter, accounting for 56% of the total BrC, followed by secondary formation, accounting for 24% of the total BrC, with road dust contributing only 6%.


Asunto(s)
Contaminantes Atmosféricos , Carbono , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Carbono/análisis , China , Monitoreo del Ambiente , Combustibles Fósiles
19.
Rejuvenation Res ; 24(4): 283-293, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33607932

RESUMEN

Umbilical cord mesenchymal stem cells (UCMSCs) have been identified as a potentially ideal cell type for use in regenerative therapeutic contexts owing to their excellent paracrine secretory abilities and other desirable properties. Previous work has shown that stem cell-derived exosomes can effectively reduce skin aging, but few studies have specifically focused on the role of UCMSC-derived exosomes in this context. In this study, we isolated exosomes derived from UCMSCs grown in a three-dimensional culture system and explored their ability to modulate the photo-aging of HaCaT keratinocytes. Cell viability and proliferation were assessed using CCK8 assay, whereas wound healing and transwell assays were used to assess cell migratory capabilities. UVB irradiation (60 mJ/cm2) was used to induce photo-aging of HaCaT cells. TUNEL and SA-ß-Gal staining were used to explore HaCaT cell apoptosis and senescence, respectively, whereas real-time quantitative PCR was used to assess the expression of relevant genes at the mRNA level. We found that UCMSC-derived exosomes were able to enhance normal HaCaT cell proliferation and migration while also inhibiting UVB-induced damage to these cells. These exosomes also reduced HaCaT cell apoptosis and senescence, increasing collagen type I expression and reducing matrix metalloproteinase (MMP1) expression in photo-aged HaCaT cells. Together, these findings indicate that UCMSC-derived exosomes have the potential to be used therapeutically to suppress skin aging.


Asunto(s)
Exosomas , Células Madre Mesenquimatosas , Envejecimiento de la Piel , Cordón Umbilical , Anciano , Proliferación Celular , Células HaCaT , Humanos , Cordón Umbilical/citología
20.
ChemSusChem ; 13(17): 4446-4454, 2020 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-32118355

RESUMEN

The valorization of lignin to replace phenol is significant in the production of phenolic resins. However, a great challenge is to produce lignin-based resin (LR) with a suitable viscosity and high substitution rate of lignin to phenol. In this study, LRs were produced using hardwood technical lignin derived from the pulping industry. Structural analysis of the LRs indicated that the unsubstituted para and ortho carbon atoms of the aromatic ring influenced the curing temperature and activation energy of the resins. The curing kinetics and thermal decomposition study implied that urea and methylene groups in cured LRs were significant factors that affected the thermal stability negatively. The prepared LRs showed desirable features if used as adhesives to make plywood. This is the first approach in which a substitution rate of up to 65 % is achieved for low-reactive-site hardwood lignin, which provides a solution to the challenge of the simultaneous realization of the high addition of lignin and the adaptive viscosity of resins.

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