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1.
Cell ; 186(16): 3350-3367.e19, 2023 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-37421950

RESUMEN

Synucleinopathies are characterized by the accumulation of α-synuclein (α-Syn) aggregates in the brain. Positron emission tomography (PET) imaging of synucleinopathies requires radiopharmaceuticals that selectively bind α-Syn deposits. We report the identification of a brain permeable and rapid washout PET tracer [18F]-F0502B, which shows high binding affinity for α-Syn, but not for Aß or Tau fibrils, and preferential binding to α-Syn aggregates in the brain sections. Employing several cycles of counter screenings with in vitro fibrils, intraneuronal aggregates, and neurodegenerative disease brain sections from several mice models and human subjects, [18F]-F0502B images α-Syn deposits in the brains of mouse and non-human primate PD models. We further determined the atomic structure of the α-Syn fibril-F0502B complex by cryo-EM and revealed parallel diagonal stacking of F0502B on the fibril surface through an intense noncovalent bonding network via inter-ligand interactions. Therefore, [18F]-F0502B is a promising lead compound for imaging aggregated α-Syn in synucleinopathies.


Asunto(s)
Enfermedades Neurodegenerativas , Sinucleinopatías , Animales , Humanos , alfa-Sinucleína/metabolismo , Sinucleinopatías/diagnóstico por imagen , Sinucleinopatías/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Tomografía de Emisión de Positrones , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo
2.
Mol Psychiatry ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38658772

RESUMEN

Early onset familial Alzheimer's disease (FAD) with APP, PS1/2 (presenilins) mutation accounts for only a small portion of AD cases, and most are late-onset sporadic. However, majority of AD mouse models are developed to mimic the genetic cause of human AD by overexpressing mutated forms of human APP, PS1/2, and/or Tau protein, though there is no Tau mutation in AD, and no single mouse model recapitulates all aspects of AD pathology. Here, we report Thy1-ApoE4/C/EBPß double transgenic mouse model that demonstrates key AD pathologies in an age-dependent manner in absence of any human APP or PS1/2 mutation. Using the clinical diagnosis criteria, we show that this mouse model exhibits tempo-spatial features in AD patient brains, including progressive cognitive decline associated with brain atrophy, which is accompanied with extensive neuronal degeneration. Remarkably, the mice display gradual Aß aggregation and neurofibrillary tangles formation in the brain validated by Aß PET and Tau PET. Moreover, the mice reveal widespread neuroinflammation as shown in AD brains. Hence, Thy1-ApoE4/C/EBPß mouse model acts as a sporadic AD mouse model, reconstituting the major AD pathologies.

3.
Environ Sci Technol ; 58(13): 5750-5759, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38506744

RESUMEN

1,1-Difluoroethane (HFC-152a) is a hydrofluorocarbon regulated by the Montreal Protocol, and its emissions in China are of concern as China will regulate HFC-152a in 2024. However, no observation-inferred top-down estimates were undertaken after 2017, and substantial gaps existed among previous estimates of China's HFC-152a emissions. Using the atmospheric observations and inverse modeling, this study reveals China's HFC-152a emissions of 9.4 ± 1.7 Gg/yr (gigagrams per year), 10.6 ± 1.8 Gg/yr, and 9.7 ± 1.5 Gg/yr in 2018, 2019, and 2020, respectively. In addition, we display an overall increasing trend during 2011-2020, which is in contrast to the decreasing and steady trend reported by the Emission Database for Global Atmospheric Research (EDGAR) and the Chinese government, respectively. Subsequently, we establish a comprehensive bottom-up emission inventory matching with top-down estimates and thus succeed in explaining the gaps among previous estimates. Furthermore, the contribution of China's emissions to global HFC-152a emission growth increased from 15% during 2001-2010 to >100% during 2011-2020. An emission projection based on our improved inventory shows that the Kigali Amendment (KA) would assist in avoiding 1535.6-4710.6 Gg (251.8-772.5 Tg CO2-eq) HFC-152a emissions during 2024-2100. Our findings indicate relatively accurate China's HFC-152a emissions and provide scientific support for addressing climate change and implementing the KA.


Asunto(s)
Gases de Efecto Invernadero , Rwanda , China , Cambio Climático
4.
Environ Res ; 259: 119549, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38964576

RESUMEN

Methane (CH4) is the second most abundant greenhouse gas. China is the largest CH4 emitter in the world, with coal mine methane (CMM) being one of the main anthropogenic contributions. Thus, there is an urgent need for comprehensive estimates and strategies for reducing CMM emissions in China. However, the development of effective strategies is currently challenged by a lack of information on temporal variations in the contributions of different CMM sources and the absence of provincial spatial analysis. Here, considering five sources and utilization, we build a comprehensive inventory of China's CMM emissions from 1980 to 2022 and quantify the contributions of individual sources to the overall CMM emissions at the national and provincial levels. Our results highlight a significant shift in the source contributions of CMM emissions, with the largest contributor, underground mining, decreasing from 89% in 1980 to 69% in 2022. Underground abandoned coal mines, which were ignored or underestimated in past inventories, have become the second source of CMM emissions since 1999. From 2011 to 2022, we identified Shanxi, Guizhou, and Shaanxi as the three largest CMM-emitting provinces, while the Emissions Database for Global Atmospheric Research (EDGAR) v8 overestimated emissions from Inner Mongolia, ranking it third. Notably, we observed a substantial decrease (exceeding 1 Mt) in CMM emissions in Sichuan, Henan, Liaoning, and Hunan between 2011 and 2022, which was not captured by EDGAR v8. To develop targeted CMM emission reduction strategies at the provincial level, we classified 31 provinces into four groups based on their CMM emission structures. In 2022, the number of provinces with CMM emissions mainly from abandoned coal mines has exceeded that of provinces with mainly underground mines, which requires attention. This study reveals the characteristics of the source of CMM emissions in China and provides emission reduction directions for four groups of provinces.

5.
Cell Mol Life Sci ; 80(5): 137, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37133566

RESUMEN

Disordered lipid accumulation in the arterial wall is a hallmark of atherosclerosis. Previous studies found that the expression of triggering receptor expressed on myeloid cells 2 (TREM2), a transmembrane receptor of the immunoglobulin family, is increased in mouse atherosclerotic aortic plaques. However, it remains unknown whether TREM2 plays a role in atherosclerosis. Here we investigated the role of TREM2 in atherosclerosis using ApoE knockout (ApoE-/-) mouse models, primary vascular smooth muscle cells (SMCs), and bone marrow-derived macrophages (BMDMs). In ApoE-/- mice, the density of TREM2-positive foam cells in aortic plaques increased in a time-dependent manner after the mice were fed a high-fat diet (HFD). Compared with ApoE-/- mice, the Trem2-/-/ApoE-/- double-knockout mice showed significantly reduced atherosclerotic lesion size, foam cell number, and lipid burden degree in plaques after HFD feeding. Overexpression of TREM2 in cultured vascular SMCs and macrophages exacerbates lipid influx and foam cell formation by upregulating the expression of the scavenger receptor CD36. Mechanistically, TREM2 inhibits the phosphorylation of p38 mitogen-activated protein kinase and peroxisome proliferator activated-receptor gamma (PPARγ), thereby increasing PPARγ nuclear transcriptional activity and subsequently promoting the transcription of CD36. Our results indicate that TREM2 exacerbates atherosclerosis development by promoting SMC- and macrophage-derived foam cell formation by regulating scavenger receptor CD36 expression. Thus, TREM2 may act as a novel therapeutic target for the treatment of atherosclerosis.


Asunto(s)
Aterosclerosis , Placa Aterosclerótica , Ratones , Animales , Células Espumosas/metabolismo , Células Espumosas/patología , PPAR gamma/genética , PPAR gamma/metabolismo , Aterosclerosis/metabolismo , Placa Aterosclerótica/metabolismo , Ratones Noqueados , Antígenos CD36/genética , Antígenos CD36/metabolismo , Colesterol/metabolismo , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Lípidos , Lipoproteínas LDL/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Receptores Inmunológicos/genética , Receptores Inmunológicos/metabolismo
6.
Ecotoxicol Environ Saf ; 281: 116563, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38878560

RESUMEN

Evodiamine (EVO), the main active alkaloid in Evodia rutaecarpa, was shown to exert various pharmacological activities, especially anti-tumor. Currently, it is considered a potential anti-cancer drug due to its excellent anti-tumor activity, which unfortunately has adverse reactions, such as the risk of liver and kidney injury, when Evodia rutaecarpa containing EVO is used clinically. In the present study, we aim to clarify the potential toxic target organs and toxicity mechanism of EVO, an active monomer in Evodia rutaecarpa, and to develop mitigation strategies for its toxicity mechanism. Transcriptome analysis and related experiments showed that the PI3K/Akt pathway induced by calcium overload was an important step in EVO-induced apoptosis of renal cells. Specifically, intracellular calcium ions were increased, and mitochondrial calcium ions were decreased. In addition, EVO-induced calcium overload was associated with TRPV1 receptor activation. In vivo TRPV1 antagonist and calcium chelator effects were observed to significantly reduce body weight loss and renal damage in mice due to EVO toxicity. The potential nephrotoxicity of EVO was further confirmed by an in vivo test. In conclusion, TRPV1-mediated calcium overload-induced apoptosis is one of the mechanisms contributing to the nephrotoxicity of EVO due to its toxicity, whereas maintaining body calcium homeostasis is an effective measure to reduce toxicity. These studies suggest that the clinical use of EVO-containing herbal medicines should pay due attention to the changes in renal function of patients as well as the off-target effects of the drugs.


Asunto(s)
Apoptosis , Calcio , Evodia , Homeostasis , Riñón , Quinazolinas , Quinazolinas/toxicidad , Quinazolinas/farmacología , Animales , Homeostasis/efectos de los fármacos , Calcio/metabolismo , Ratones , Apoptosis/efectos de los fármacos , Riñón/efectos de los fármacos , Riñón/patología , Evodia/química , Masculino , Canales Catiónicos TRPV/metabolismo , Quelantes del Calcio/farmacología
7.
Anal Chem ; 95(28): 10486-10491, 2023 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-37418553

RESUMEN

To overcome the insufficient sensitivity due to distortion of the fluorescent images by mobile devices, we first developed a novel dual-mode strategy for undistorted visual fluorescent sensing on µPAD by technically manipulating the coffee-ring effect of the fluid sample. Based on the manipulating coffee-ring effect, we divided the horizontal direction of the resulting fluorescence image into 600 pixels and obtained more accurate quantitative information to avoid image distortion. The bovine serum albumin-stabilized gold nanoclusters-copper ion complex was used as the fluorescent probe, combined with a small imaging box and a smartphone, to achieve a rapid testing of histidine in human urine. The output image was analyzed in dual mode: RGB numerical analysis in pixel units and the direct measurement of the fluorescent strips length (limit of detection (LOD) is 0.021 and 0.5 mM, respectively), and improved antidistortion for visual fluorescent sensing. This strategy can overcome the distortion of a smartphone-visualized fluorescent image and shows great potential for rapid and convenient analysis.


Asunto(s)
Microfluídica , Teléfono Inteligente , Humanos , Límite de Detección , Colorantes Fluorescentes , Oro , Espectrometría de Fluorescencia/métodos
8.
Analyst ; 148(23): 5896-5904, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37847494

RESUMEN

Based on surface biomolecular imprinting technology, a rotary microfluidic electrochemical paper-based chip (MIP-ePADs) was proposed for sensitive and selective detection of human interleukin 6 (IL-6) and procalcitonin (PCT). Compared with the traditional method, the sample can be added directly on the MIP-ePAD by rotating the working electrode, which avoids the loss of the liquid to be tested and greatly simplifies the process of electropolymerization imprinting and template elution. Our experimental results show that linear concentration ranges of IL-6 and PCT in the electrochemical molecularly imprinted microfluidic paper-based chip ranged from 0.01 to 5 ng mL-1, with their detection limits being 3.5 and 2.1 pg mL-1, respectively. For the detection of actual serum samples, there was no significant difference between the results of MIP-ePADs and the traditional electrochemiluminescence method used in hospitals, indicating that the paper-based chip can be used for stable and accurate analysis and detection. The chip greatly reduces the cost of clinical trials due to its advantages of easy preparation and low cost. The chip can be used for the analysis of non-antibody inflammation markers and can be widely used in home and hospital treatment detection. This method will not only play an important role in rapid detection, but also provide new ideas for the improvement of rapid detection technology.


Asunto(s)
Impresión Molecular , Polipéptido alfa Relacionado con Calcitonina , Humanos , Interleucina-6 , Microfluídica , Impresión Molecular/métodos , Electrodos , Técnicas Electroquímicas/métodos , Límite de Detección
9.
Environ Sci Technol ; 57(48): 19557-19564, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37978918

RESUMEN

Having the highest ozone-depleting potential among hydrochlorofluorocarbons (HCFCs), the production and consumption of HCFC-141b (1,1-dichloro-1-fluoroethane, CH3CCl2F) are controlled by the Montreal Protocol. A renewed rise in global HCFC-141b emissions was found during 2017-2020; however, the latest changes in emissions across China are unclear for this period. This study used the FLEXible PARTicle dispersion model and the Bayesian framework to quantify HCFC-141b emissions based on atmospheric measurements from more sites across China than those used in previous studies. Results show that the estimated HCFC-141b emissions during 2018-2020 were on average 19.4 (17.3-21.6) Gg year-1, which was 3.9 (0.9-7.0) Gg year-1 higher than those in 2017 (15.5 [13.4-17.6] Gg year-1), showing a renewed rise. The proportion of global emissions that could not be exactly traced in 2020 was reduced from about 70% reported in previous studies to 46% herein. This study reconciled the global emission rise of 3.0 ± 1.2 Gg year-1 (emissions in 2020 - emissions in 2017): China's HCFC-141b emissions changed by 4.3 ± 4.5 Gg year-1, and the combined emissions from North Korea, South Korea, western Japan, Australia, northwestern Europe, and the United States changed by -2.2 ± 2.6 Gg year-1, while those from other countries/regions changed by 0.9 ± 5.3 Gg year-1.


Asunto(s)
Clorofluorocarburos , Clorofluorocarburos/análisis , Teorema de Bayes , Clorofluorocarburos de Etano , China
10.
BMC Musculoskelet Disord ; 24(1): 797, 2023 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-37805527

RESUMEN

BACKGROUND: Oxidized regenerated cellulose (ORC) is a type of biodegradable hemostatic material, which has been widely used in the field of surgery. However, its hemostatic effect in patients undergoing total knee arthroplasty (TKA) is uncertain. Accordingly, this study investigated the effectiveness and safety of ORC in patients receiving TKA. METHODS: Seventy patients undergoing unilateral TKA were randomized into blank control group and ORC (2 pieces of ORC placed in the joint cavity) groups. Then, the two groups were compared for primary (perioperative blood loss [total blood loss, intraoperative blood loss, and hidden blood loss] and hemoglobin drop values) and secondary (coagulation indicators, inflammatory indicators,operation time, and complication rates) outcomes. RESULTS: The total blood loss in the ORC group was 902.32 ± 307.82 mL, which was statistically significantly lower than that in the control group (1052.25 ± 308.44 mL) (P < 0.05). Postoperative hidden blood loss was also statistically markedly lower in the ORC group (801.61 ± 298.80 mL) than in the control group (949.96 ± 297.59 mL) (P < 0.05). There was no significant difference between the two groups in terms of coagulation indicators, inflammatory indicators, operation time, and complication rates. CONCLUSION: In conclusion, our prospective RCT study proved that regenerated oxidized cellulose can be used safely in vivo and can effectively reduce postoperative blood loss in patients, which is a potential method for preventing blood loss after TKA. TRIAL REGISTRATION: This prospective RCT was reviewed and approved by the Ethics Committee of Honghui Hospital of Xi'an Jiaotong University (No: 202,211,007) and was designed and conducted according to the rules of the Declaration of Helsinki. Written informed consent was obtained from patients or their legal guardians.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Celulosa Oxidada , Hemostáticos , Humanos , Celulosa Oxidada/efectos adversos , Hemostáticos/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Estudios Prospectivos , Pérdida de Sangre Quirúrgica/prevención & control , Hemorragia Posoperatoria/prevención & control
11.
Microchem J ; 185: 108304, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36531593

RESUMEN

Coronavirus disease 2019 (COVID-19) and influenza A are two respiratory infectious diseases with similar clinical manifestations. Because of the complex global epidemic situation of COVID-19, the distinction and diagnosis of COVID-19 and influenza A infected persons is crucial for epidemic prevention and control. In this study, tetrahedral DNA framework (TDF) was combined with a rotational paper-based analytical device, and the color change generated by the reaction between horseradish peroxidase (HRP) and 3,3'5,5'-tetramethylbenzidine (TMB)-H2O2 was used for grayscale signal analysis by ImageJ software. The quantitative detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza A H1N1 virus were realized simultaneously. Under the optimal conditions, the paper-based analytical device showed a good linear relationship between the two viruses in the range of 10-14-10-8g/mL, and the two viruses were not affected by cross reaction. This sensor provides a convenient and reliable method for clinical rapid differentiation and diagnosis of COVID-19 and influenza A.

12.
Sensors (Basel) ; 23(6)2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36991805

RESUMEN

Traces of mercury ions in environmental water can harm humans and animals. Paper-based visual detection methods have been widely developed for the rapid detection of mercury ions; however, existing methods are not sensitive enough to be used in real environments. Here, we developed a novel, simple and effective visual fluorescent sensing paper-based chip for the ultrasensitive detection of mercury ions in environmental water. CdTe-quantum-dots-modified silica nanospheres were firmly absorbed by and anchored to the fiber interspaces on the paper's surface to effectively avoid the unevenness caused by liquid evaporation. The fluorescence of quantum dots emitted at 525 nm can be selectively and efficiently quenched with mercury ions, and the ultrasensitive visual fluorescence sensing results attained using this principle can be captured using a smartphone camera. This method has a detection limit of 2.83 µg/L and a fast response time (90 s). We successfully achieved the trace spiking detection of seawater (from three regions), lake water, river water and tap water with recoveries in the range of 96.8-105.4% using this method. This method is effective, low-cost, user-friendly and has good prospects for commercial application. Additionally, the work is expected to be utilized in the automated big data collection of large numbers of environmental samples.

13.
J Environ Sci (China) ; 124: 723-734, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36182177

RESUMEN

Understanding the emission sources of volatile organic compounds (VOCs) is critical for air pollution mitigation. Continuous measurements of atmospheric VOCs were conducted from January to February in Hangzhou in 2021. The average measured concentration of total VOCs (TVOCs) was 38.2 ± 20.9 ppb, > 42% lower than that reported by previous studies at the urban center in Hangzhou. The VOC concentrations and proportions were similar between weekdays and weekends. During the long holidays of the Spring Festival in China, the concentrations of TVOCs were ∼50% lower than those during the regular days, but their profiles showed no significant difference (p > 0.05). Further, we deduced that aromatics and alkenes were the most crucial chemicals promoting the formation of O3 and secondary organic aerosol (SOA) in Hangzhou. According to interspecies correlations, combustion processes and solvent use were inferred as major VOC emission sources. This study provides implications for air quality improvements before and during the upcoming Asian Games that will be hosted in Hangzhou in 2022.


Asunto(s)
Contaminantes Atmosféricos , Ozono , Compuestos Orgánicos Volátiles , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Alquenos/análisis , China , Monitoreo del Ambiente , Ozono/análisis , Solventes , Compuestos Orgánicos Volátiles/análisis
14.
FASEB J ; 35(11): e21942, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34670018

RESUMEN

Atherosclerosis is a chronic inflammatory disease. Pathophysiological similarities between chronic infections and atherosclerosis triggered interests between these conditions. The seroepidemiological study showed that Helicobacter pylori strains that express cytotoxin-associated gene A (CagA), an oncoprotein and a major virulence factor, was positively correlated with atherosclerosis and related clinical events. Nevertheless, the underlying mechanism is poorly understood. In this study, the seroprevalence of infection by H. pylori and by strains express CagA assessed by enzyme-linked immunosorbent assay (ELISA) showed that the prevalence of CagA strains rather than H. pylori in patients was positively correlated with atherogenesis. Correspondingly, we found that CagA augmented the growth of plaque of ApoE-/- mice in the early stage of atherosclerosis and promoted the expression of adhesion molecules and inflammatory cytokines in mouse aortic endothelial cells (MAECs). Mechanistically, both si-NLRP3 and si-IL-1ß mitigated the promoting effect of CagA on the inflammatory activation of HAECs. In vivo, the inhibition of NLRP3 by MCC950 significantly attenuated the promoting effect of CagA on plaque growth of ApoE-/- mice. We also propose NLRP3 as a potential therapeutic target for CagA-positive H. pylori infection-related atherosclerosis and emphasize the importance of inflammation in atherosclerosis pathology.


Asunto(s)
Antígenos Bacterianos/metabolismo , Aorta/patología , Aterosclerosis/sangre , Proteínas Bacterianas/metabolismo , Caspasa 1/metabolismo , Células Endoteliales/metabolismo , Infecciones por Helicobacter/sangre , Helicobacter pylori/metabolismo , Interleucina-1beta/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Placa Aterosclerótica/sangre , Anciano , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Antígenos Bacterianos/inmunología , Aorta/metabolismo , Aterosclerosis/microbiología , Proteínas Bacterianas/inmunología , Modelos Animales de Enfermedad , Femenino , Infecciones por Helicobacter/inmunología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/inmunología , Humanos , Inflamación/inmunología , Inflamación/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados para ApoE , Persona de Mediana Edad , Placa Aterosclerótica/microbiología , Estudios Seroepidemiológicos , Células THP-1
15.
Analyst ; 147(16): 3756-3763, 2022 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-35851335

RESUMEN

Ion imprinting technology was integrated on a rotational microfluidic paper- and cloth-based hybrid chip for the sensitive and selective detection of hexavalent chromium (Cr(VI)) ions. The rotational microfluidic hybrid chip consisted of CdTe quantum dot based ion imprinting fluorescence sensing cloth and three layers of paper. Users can collect fluorescence signals conveniently via rotating the paper layer to expose the corresponding cloth-based sensing component. One microfluidic hybrid chip can realize the four-set multiplexed detection of Cr(VI) ions, with each set providing three parallel measurements. Furthermore, the quantitative determination of Cr(VI) ions can be achieved via substituting the calculated fluorescence quenching value into the linear calibration curve. The ion imprinting fluorescence sensing microfluidic hybrid chip provides a simple, efficient, and user-friendly device for Cr(VI) ion detection. Moreover, it might be further adapted for other sensing systems and the point-of-care testing of pollutants in combination with portable instruments or smartphones.


Asunto(s)
Compuestos de Cadmio , Puntos Cuánticos , Cromo , Iones , Microfluídica , Telurio
16.
Analyst ; 147(6): 1060-1065, 2022 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-35191458

RESUMEN

Microcystin has been causing serious environmental pollution; however, the recognition of such compounds is still challenging because of low abundance and coexisting interfering species. In this contribution, we develop a novel microfluidic paper-based colorimetric sensor by exploiting molecular imprinting technology and Fenton reaction for on-site microcystin-RR determination in complex water samples using a smartphone.


Asunto(s)
Impresión Molecular , Polímeros , Catálisis , Microcistinas , Microfluídica
17.
Environ Res ; 214(Pt 2): 113944, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35870498

RESUMEN

China has shut down and abandoned a substantial number of coal mines since 1999, which have been releasing methane (CH4) for many years. However, the characteristics of China's abandoned mine methane (AMM) emissions are still unclear; this is a concerning knowledge gap because coal mines are the largest contributor to China's anthropogenic CH4 emissions. This study used two methods to estimate China's historical AMM emissions over the past 40 years (1980-2020) and to project its AMM emissions to 2060 which is the target year for China's carbon neutrality goal. The results show that China's AMM emissions increased substantially from 0.11 ± 0.03 million tons per year (Mt/yr) (3.1 ± 0.84 Mt/yr CO2-eq) in 1980 to 4.7 ± 0.94 Mt/yr (131 ± 26 Mt/yr CO2-eq) in 2020. An accelerated growth rate was found during 1998-2005, with AMM emissions rapidly increasing by approximately three times, which was consistent with the high number of mine shutdowns. In 2019, we found that AMM emissions had become the fourth largest anthropogenic source in China, higher than the national anthropogenic CH4 emissions of individual United Nations Framework Convention on Climate Change Annex I countries excluding the United States of America and the Russian Federation. If unabated, China's AMM emissions are projected to peak at 8.7 ± 2.6 Mt/yr in 2040 and reach approximately one-third of China's anthropogenic carbon dioxide emissions in 2060. This study reveals that understanding AMM emissions can help more accurately quantify China's total CH4 emissions and guide their future mitigation.


Asunto(s)
Dióxido de Carbono , Metano , Dióxido de Carbono/análisis , Cambio Climático , Carbón Mineral , Metano/análisis , Minería , Estados Unidos
18.
Analyst ; 146(17): 5255-5263, 2021 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-34324622

RESUMEN

In this article, we present a novel nitrocellulose-based microfluidic chip with 3-dimensional (3D) printing technology to study the effect of oxygen gradient on cells. Compared with conventional polydimethylsiloxane (PDMS) chips of oxygen gradient for cell cultures that can only rely on fluorescence microscope analysis, this hybrid nitrocellulose-based microfluidic platform can provide a variety of analysis methods for cells, including flow cytometry, western blot and RT-PCR, because the nitrocellulose-based chips with cells can be taken out from the growth chambers of 3D printed microfluidic chip and then used for cell collection or lysis. These advantages allow researchers to acquire more information and data on the basic biochemical and physiological processes of cell life. The effect of oxygen gradient on the zebrafish cells (ZF4) was used as a model to show the performance and application of our platform. Hypoxia caused the increase of intercellular reactive oxygen species (ROS) and accumulation of hypoxia-inducible factor 1α (HIF-1α). Hypoxia stimulated the transcription of hypoxia-responsive genes vascular endothelial growth factor (VEGF) and induced cell cycle arrest of ZF4 cells. The established platform is able to obtain more information from cells in response to different oxygen concentration, which has potential for analyzing the cells under a variety of pathological conditions.


Asunto(s)
Microfluídica , Oxígeno , Animales , Hipoxia de la Célula , Colodión , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Impresión Tridimensional , Factor A de Crecimiento Endotelial Vascular/genética , Pez Cebra/metabolismo
19.
Environ Res ; 193: 110461, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33188762

RESUMEN

BACKGROUND: Many volatile organic compounds (VOCs) are efficient precursors for both ozone and secondary organic aerosol (SOA) which are problematic to environmental controls in many global cities. Vehicle emission is one of the most important anthropogenic sources for VOCs. In between, light duty gasoline passenger vehicles (LDGPVs) contributed more than half of the on-road vehicles in China, demonstrating unique emission characteristics and also significant contributions in emission inventory. OBJECTIVES: To illustrate the variation of VOCs emissions from LDGPVs under different conditions, evaluate the sensitivity of the potential influencing factors, such as emission standards, displacement, cumulative mileage, and driving mode, on the VOCs emissions profiles, and to update the emission inventory by taking into account of the most influential factor. METHODS: In this study, seventy-four in-used LDGPVs were examined by the chassis dynamometer. A total of 25 VOCs in the emissions was quantified using an online time of flight mass spectrometer (TOF-MS). Fuel-based emission factors (EF) were calculated. RESULTS: The results showed that the maximum ΣEF (260.4 ± 241.1 mg/L) was seen for LDGPVs at a high acceleration rate (0.9 m/s2). From the technical control emission standard aspect, the total emission factor of VOCs (expressed as ∑EF) was declined for China IV LDGPVs relative to China III vehicles, with the decreasing extent determined as 24.8%. Among LDGPVs with engine capacity of <1.5 L, 1.5-2.5 L and >2.5 L, it is for 1.5-2.5 L that the lowest ∑EF (101.2 ± 70.1 mg/L) was determined. Along with the increasing of cumulative mileage, the EF values of VOCs were uplift, and the ∑VOCs increased almost linearity, while the increasing trend became steady for ∑EF when the cumulative mileage more than 8 × 104 km. As for different driving conditions, the sequence of EFs from high to low are presented as acceleration (239.3 ± 203.5 mg/L) >idle (226.1 ± 195.6 mg/L) >deceleration (218.5 ± 193.1 mg/L)>uniform (218.2 ± 182.5 mg/L)>slide (176.1 ± 165.2 mg/L). While the cruising speeds increased between 15 and 50 km/h, the linearity between ΣEF declined; however, an opposite trend was seen when the acceleration rates increased. In the chemical speciation, the reactive aromatics contributed the largest fraction of the VOCs (>40%). The ratio of benzene to toluene (B/T) was loaded in high interval (0.94-1.33) in this paper. Larger fluctuation of coefficient of variation (CV) was found among different cumulative mileage and displacement. By taking into account the deterioration effect related to cumulative mileage, emissions of butene, pentene, benzene and toluene were 42.9 Gg, 49.7 Gg, 109.6 Gg and 51.9 Gg in respect for LDGPVs that composed of China III and China IV. CONCLUSIONS: Our results demonstrated the necessaries in upgrading the emission control technology. Cumulative mileages and displacements are the two most dominated factors that impacted on the EFs and chemical profiles of VOCs. The higher emission of benzene estimated demonstrated the possible elevation of VOCs in comparison with previous studies.


Asunto(s)
Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , China , Ciudades , Monitoreo del Ambiente , Gasolina , Emisiones de Vehículos/análisis , Compuestos Orgánicos Volátiles/análisis
20.
Cell Mol Life Sci ; 77(14): 2751-2769, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32002588

RESUMEN

Atherosclerotic vascular disease (ASVD) is a chronic process, with a progressive course over many years, but it can cause acute clinical events, including acute coronary syndromes (ACS), myocardial infarction (MI) and stroke. In addition to a series of typical risk factors for atherosclerosis, like hyperlipidemia, hypertension, smoking and obesity, emerging evidence suggests that atherosclerosis is a chronic inflammatory disease, suggesting that chronic infection plays an important role in the development of atherosclerosis. Toll-like receptors (TLRs) are the most characteristic members of pattern recognition receptors (PRRs), which play an important role in innate immune mechanism. TLRs play different roles in different stages of infection of atherosclerosis-related pathogens such as Chlamydia pneumoniae (C. pneumoniae), periodontal pathogens including Porphyromonas gingivalis (P. gingivalis), Helicobacter pylori (H. pylori) and human immunodeficiency virus (HIV). Overall, activation of TLR2 and 4 seems to have a profound impact on infection-related atherosclerosis. This article reviews the role of TLRs in the process of atherosclerosis after C. pneumoniae and other infections and the current status of treatment, with a view to providing a new direction and potential therapeutic targets for the study of ASVD.


Asunto(s)
Aterosclerosis/genética , Infecciones Bacterianas/genética , Infecciones por VIH/genética , Receptores Toll-Like/genética , Aterosclerosis/complicaciones , Aterosclerosis/microbiología , Aterosclerosis/virología , Infecciones Bacterianas/complicaciones , Infecciones Bacterianas/microbiología , Infecciones Bacterianas/virología , Chlamydophila pneumoniae/patogenicidad , VIH/patogenicidad , Infecciones por VIH/complicaciones , Infecciones por VIH/microbiología , Infecciones por VIH/virología , Helicobacter pylori/patogenicidad , Humanos , Porphyromonas gingivalis/patogenicidad
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