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1.
Metab Brain Dis ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842661

RESUMO

Subarachnoid hemorrhage (SAH) is a serious hemorrhagic event with high mortality and morbidity. Multiple injurious events produced by SAH can lead to a series of pathophysiologic processes in the hypothalamus that can severely impact patients' life. These pathophysiologic processes usually result in physiologic derangements and dysfunction of the brain and multiple organs. This dysfunction involved multiple dimensions of the genome and metabolome. In our study, we induced the SAH model in rats to obtain hypothalamic tissue and serum. The samples were subsequently analyzed by transcriptomics and metabolomics. Next, the functional enrichment analysis of the differentially expressed genes and metabolites were performed by GO and KEGG pathway analysis. Through transcriptomic analysis of hypothalamus samples, 263 up-regulated differential genes, and 207 down-regulated differential genes were identified in SAH groups compared to Sham groups. In the KEGG pathway analysis, a large number of differential genes were found to be enriched in IL-17 signaling pathway, PI3K-Akt signaling pathway, and bile secretion. Liquid chromatography-mass spectrometry metabolomics technology was conducted on the serum of SAH rats and identified 11 up-regulated and 26 down-regulated metabolites in positive ion model, and 1 up-regulated and 10 down-regulated metabolites in negative ion model. KEGG pathways analysis showed that differentially expressed metabolites were mainly enriched in pathways of bile secretion and primary bile acid biosynthesis. We systematically depicted the neuro- and metabolism-related biomolecular changes occurring in the hypothalamus after SAH by performing transcriptomics and metabolomics studies. These biomolecular changes may provide new insights into hypothalamus-induced metabolic changes and gene expression after SAH.

2.
Environ Sci Technol ; 57(49): 20773-20780, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37906162

RESUMO

Iodine is a crucial nutrient for public health, and its presence in the terrestrial atmosphere is a key factor in determining the prevalence of iodine deficiency disorders. While oceanic iodine emissions decrease at lower sea surface temperatures, the primary contributors to atmospheric iodine can vary from oceanic sources in the summer to other sources in winter. However, the specific sources and their respective contributions have remained unexplored. Fortunately, the atomic ratio of 129I to 127I significantly differs between nuclear activity and fossil fuels like coal and petroleum, which formed millions to billions of years ago. This distinction makes 129I a valuable tool for identifying iodine sources. In our study, we analyzed iodine isotopes and incorporated additional indicators such as element content in PM2.5 samples. Our findings reveal, for the first time, that in winter inland areas, fuel oil, alongside coal combustion, is a significant source of atmospheric iodine. This research enhances our comprehension of the impact of human activities on iodine levels in the environment. This understanding is crucial not only for addressing iodine deficiency-related health concerns but also for comprehending stratospheric ozone depletion, a phenomenon closely associated with atmospheric iodine.


Assuntos
Poluentes Atmosféricos , Iodo , Petróleo , Humanos , Combustíveis Fósseis/análise , Poluentes Atmosféricos/análise , Carvão Mineral , Monitoramento Ambiental
3.
Environ Sci Technol ; 57(26): 9732-9743, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37345322

RESUMO

Microplastics (MPs) are emerging pollutants, and limited research has focused on their exposure to terrestrial wildlife and transport mode on the remote Tibetan Plateau (TP). Therefore, we investigated MPs in the southern soil and feces of Equus kiang (Tibetan wild ass), a species peculiar to the TP, which is known as the "third pole." We found that MP median abundances were 102 and 4.01 particles/g of dry feces and soil, respectively. In both media, the MP morphology mainly comprised ∼50 µm slender fibrous particles. In total, 29 MP types were identified in the feces, compared to 26 types in the soil. Among them, the acrylate copolymer (35.9%) and polyurethane (24.9%) were predominant in the feces, while polyurethane (22.5%) and silicone (20.4%) were predominant in the soil. After ingesting MPs at one location, E. kiang may become a source of MP pollution when moving to other meadows on the TP. The potential MP transport flux of a herd of 20 kiangs has been estimated at 1736 particles m-2 a-1. A unique "source-sink-source" MP transport model comprising an "atmospheric deposition-vegetation-feces-atmosphere" cycle on the TP was observed based on atmospheric transport simulations and terrestrial food chain transfer processes. Owing to human settlements in south and East Asia adjacent to the TP, atmospheric long-distance transmission is an essential route for MPs to enter the TP.


Assuntos
Microplásticos , Plásticos , Animais , Humanos , Tibet , Solo , Poliuretanos , China , Equidae , Fezes , Monitoramento Ambiental
4.
Nature ; 544(7651): 465-470, 2017 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-28424513

RESUMO

The ability to visualize directly a large number of distinct molecular species inside cells is increasingly essential for understanding complex systems and processes. Even though existing methods have successfully been used to explore structure-function relationships in nervous systems, to profile RNA in situ, to reveal the heterogeneity of tumour microenvironments and to study dynamic macromolecular assembly, it remains challenging to image many species with high selectivity and sensitivity under biological conditions. For instance, fluorescence microscopy faces a 'colour barrier', owing to the intrinsically broad (about 1,500 inverse centimetres) and featureless nature of fluorescence spectra that limits the number of resolvable colours to two to five (or seven to nine if using complicated instrumentation and analysis). Spontaneous Raman microscopy probes vibrational transitions with much narrower resonances (peak width of about 10 inverse centimetres) and so does not suffer from this problem, but weak signals make many bio-imaging applications impossible. Although surface-enhanced Raman scattering offers high sensitivity and multiplicity, it cannot be readily used to image specific molecular targets quantitatively inside live cells. Here we use stimulated Raman scattering under electronic pre-resonance conditions to image target molecules inside living cells with very high vibrational selectivity and sensitivity (down to 250 nanomolar with a time constant of 1 millisecond). We create a palette of triple-bond-conjugated near-infrared dyes that each displays a single peak in the cell-silent Raman spectral window; when combined with available fluorescent probes, this palette provides 24 resolvable colours, with the potential for further expansion. Proof-of-principle experiments on neuronal co-cultures and brain tissues reveal cell-type-dependent heterogeneities in DNA and protein metabolism under physiological and pathological conditions, underscoring the potential of this 24-colour (super-multiplex) optical imaging approach for elucidating intricate interactions in complex biological systems.


Assuntos
Imagem Molecular/métodos , Análise Espectral Raman/métodos , Vibração , Animais , Encéfalo/citologia , Linhagem Celular , Sobrevivência Celular , Técnicas de Cocultura , Cor , Corantes/análise , Corantes/química , DNA/metabolismo , Elétrons , Corantes Fluorescentes/análise , Corantes Fluorescentes/química , Humanos , Raios Infravermelhos , Camundongos , Neurônios/citologia , Especificidade de Órgãos , Proteínas/metabolismo
5.
Retina ; 43(1): 130-137, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36542083

RESUMO

PURPOSE: To assess morphologic characteristics of retinal arterial macroaneurysm (RAM) and their vascular changes using optical coherence tomography angiography (OCTA). METHODS: This observational study included 31 eyes of 29 participants diagnosed with RAM based on fundus fluorescein angiography in Tianjin Medical University Eye Hospital. Multimodal imaging modalities, including fundus photography, fluorescein angiography, and OCTA, were used to examine RAMs. The demographic and clinical characteristics of the RAMs were recorded. RESULTS: Depending on the fundus fluorescein angiography examination, 40 cases of RAM were confirmed in 29 patients. Twenty-three patients were female (79%), and six patients were male (21%). Two patients had binocular RAM, and four eyes had more than one RAMs. Relying on the OCTA technology, RAMs have four different vascular morphology types (i.e., distended, meshed, malformed, and occult types). In the distended type, round or encircled thrombi caused asymmetrical or symmetrical distention of retinal arteriolar, leading to separate true lumen and false thrombus lumen in RAM. In the meshed type, the meshed or dendritic vascular network around the RAM was likely to be the neovascularization due to the ischemia and hypoxia of the arteriolar wall. Finally, in the malformed and occult type, the RAM usually regressed, and the retinal arterioles were remodeled to distorted or normal arterioles accompanied by capillary degradation. CONCLUSION: Relying on the OCTA technology, we found that the RAMs have four different types of vascular morphology. Each group of RAM has different vascular features. The application of OCTA in patients with RAM furthers our understanding of the vasculature of RAMs.


Assuntos
Macroaneurisma Arterial Retiniano , Masculino , Feminino , Humanos , Tomografia de Coerência Óptica/métodos , Vasos Retinianos , Angiofluoresceinografia/métodos , Retina , Fundo de Olho
6.
Angew Chem Int Ed Engl ; 62(26): e202304256, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37186137

RESUMO

Although the incorporation of 2D perovskite into 3D perovskite can greatly enhance intrinsic stability, power conversion efficiency (PCE) of 2D/3D perovskite is still inferior to its 3D counterpart due to poor carrier transport kinetics resulted from the quantum and dielectric confinement of 2D component. To overcome this issue, the electron acceptor molecule 1,2,4,5-tetracyanobenzene (TCNB) was introduced to trigger intermolecular π-π interaction in 2D perovskite along with the electronic doping of 2D/3D perovskite to improve charge transfer efficiency. By virtue of high electron affinity, TCNB can undergo electron transfer reaction and subsequently establish π-π interaction with 1-naphthalenemethylammonium (NMA) cations, greatly strengthening lattice rigidity and reducing exciton binding energy. Transmission electron microscopy results demonstrate that 2D phases are mainly distributed at grain boundaries, reducing defect density and weakening nonradiative recombination. Meanwhile, the p-type doping of perovskite by TCNB optimizes energy level alignment at perovskite/hole transport layer interface. Consequently, PCE of champion device is significantly boosted to 24.01 %. The unencapsulated device retains an initial efficiency close to 94 % after exposure to ambient environment for over 1000 h. This work paves a novel path for designing new mixed-dimensional perovskite solar cells with high PCE and superior stability.


Assuntos
Elétrons , Oxidantes , Cinética
7.
Anal Chem ; 94(27): 9835-9843, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35771968

RESUMO

Atmospheric iodine cycling is of significance in climate change and environmental and health impacts. To better explore speciation transformation of atmospheric stable and radioactive iodine, an ultra-sensitive analytical method was established for determination of 129I and 127I in particulate, gaseous inorganic, and gaseous organic species, which was conducted with a self-designed cascade sampling apparatus, followed by their separation with a pyrolysis system and accelerator mass spectrometry and ICP-MS measurements. Combustion protocols for three sampling matrices and NaOH concentration for iodine trapping were optimized to achieve a safe analytical procedure with a high chemical yield of iodine. Based on the lowest concentrations of 129I and 127I, a suitable activated carbon product for adsorption of gaseous organic iodine was carefully selected. The detection limits of the three species were 0.30-2.21 ng m-3 for 127I and 0.05-0.22 × 105 atoms m-3 for 129I. This newly established method was successfully applied to analyze the levels and species of 129I and 127I in ambinet air from Xi'an, China, from May to August, 2020. Gaseous organic iodine was found to be the dominant species of 127I and 129I, accounting for about half of total iodine, and gaseous inorganic iodine and particulate iodine accounted for one-quarter each during the whole sampling period. Speciation variation of 129I and 127I indicates that speciation transformation apparently occurred at the turn of spring and summer, mainly between particulate and gaseous organic iodine. This study has implications on delicate tracing of the atmospheric behavior of iodine with long-lived anthropogenic 129I.


Assuntos
Poluentes Atmosféricos , Iodo , Neoplasias da Glândula Tireoide , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Gases/análise , Humanos , Iodetos/análise , Radioisótopos do Iodo , Material Particulado/análise
8.
Environ Sci Technol ; 56(17): 12298-12306, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35947771

RESUMO

Anthropogenic 129I has been dispersed all over the world and could be utilized as an oceanographic tracer based on its conservative nature in the ocean. The first datasets of 129I and 127I were obtained by analysis of seawater of 36 water columns collected in the western South China Sea during August-September 2018. The measured 129I concentrations decreased with depth from (0.93-1.61) × 107 atoms/L in the upper 200 m to (0.04-0.14) × 107 atoms/L at 1500 m, indicating a clear anthropogenic source in the upper layer, mainly originated from the global fallout. The riverine input of the deposited 129I on the catchment area of the Mekong River is an important source besides the direct deposition in the seas. The water mass with high 129I from the Mekong River water moves to the east at 11°N by the North Nansha Current in the surface layer (2-25 m). The exponentially decreasing 129I level with depth indicates that the vertical dispersion of 129I from the upper to the lower layer was mainly through slow diffusion, and the deep water at more than 1500 m was not significantly contaminated by the upper layer water at least in the past 70 years.


Assuntos
Radioisótopos do Iodo , Poluentes Químicos da Água , China , Monitoramento Ambiental , Radioisótopos do Iodo/análise , Oceanos e Mares , Água do Mar , Água , Poluentes Químicos da Água/análise
9.
Mol Biol Rep ; 49(8): 7507-7519, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35622308

RESUMO

INTRODUCTION: Glioma is the most common malignant brain tumor in adults. The effects of conventional treatment regimens are still limited to prolonging the survival of patients. Histone deacetylases (HDACs) are potential targets for tumor treatment. Pracinostat is a new type of HDAC inhibitor (HDACi) that has a significant antitumor effect on a variety of tumors. Thus, we aim to investigate the role of pracinostat in human glioma and explored its underlying mechanism. METHODS: Cell viability, proliferation and apoptosis of human glioma cell lines were measured by Cell Counting kit 8 and flow cytometry. Pathway verification and protein interaction were determined by quantitative real-time polymerase chain reaction, Western blotting and immunofluorescence staining. Transwell technology was used to assess the migration and invasion of cells. Clinical significance of TIMP3, MMP9 and MMP2 in glioma was analyzed through The Cancer Genome Atlas (TCGA) database and the Genotype-Tissue Expression (GTEx) database. RESULTS: Functionally, pracinostat not only inhibited proliferation and induced apoptosis but also inhibited migration and invasion in human glioma cell lines. Mechanistically, pracinostat increased the expression of TIMP3 and decreased the expression of MMP2, MMP9 and VEGF in human glioma cells in vitro and in vivo. In addition, pracinostat inhibited both the PI3K/Akt signaling pathway and the STAT3 pathway. CONCLUSIONS: Our results strongly support the potential clinical use of pracinostat as a novel therapy for human glioma in the near future.


Assuntos
Glioma , Inibidores de Histona Desacetilases , Adulto , Apoptose , Benzimidazóis , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Glioma/tratamento farmacológico , Glioma/genética , Glioma/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Fenótipo , Fosfatidilinositol 3-Quinases/genética
10.
BMC Surg ; 21(1): 405, 2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34837986

RESUMO

BACKGROUND: Hemangiopericytoma (HPC), also known as solitary fibrous tumor (SFT), is a type of soft tissue sarcoma with a special aggressive behavior. The HPC/SFT is locally aggressive with possibility of late recurrence locally or distant extraneural metastasis. The most common location of this HPC/SFT is the lower extremities. The HPC/SFT in the central nervous system (CNS) is very rare, and compared with the brain, it is rarer in the spinal region. However, clinicians also lack an overall understanding of the diagnosis of HPC/SFT in the spinal cord. CASE PRESENTATION: In this study, we report a rare case of primary cervical spine HPC/SFT in a 53-year-old woman. Two to three weeks before admission, she experienced pain and numbness in her left upper extremity. After computerized tomography (CT) and magnetic resonance imaging (MRI), a gross total resection was performed. Obvious neurological improvement was observed postoperatively. The pain and numbness in the patient's left upper limb were relieved subsequently. We then reviewed the literature on HPC/SFT, such as its clinical presentation, imaging characteristics, treatment, and follow-up. CONCLUSIONS: Diagnosis of HPC/SFT relies on magnetic resonance spectroscopy, enhanced CT, and MRI. Postoperative radiotherapy is strongly recommended to reduce the HPC/SFT recurrence. Immunohistochemical analysis can also help in the differential diagnosis. However; early and long-term follow-up is necessary for patients.


Assuntos
Hemangiopericitoma , Tumores Fibrosos Solitários , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Diagnóstico Diferencial , Feminino , Hemangiopericitoma/diagnóstico por imagem , Hemangiopericitoma/cirurgia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Tumores Fibrosos Solitários/diagnóstico por imagem , Tumores Fibrosos Solitários/cirurgia
11.
Proc Natl Acad Sci U S A ; 114(51): 13394-13399, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29196526

RESUMO

Membrane phase behavior has been well characterized in model membranes in vitro under thermodynamic equilibrium state. However, the widely observed differences between biological membranes and their in vitro counterparts are placing more emphasis on nonequilibrium factors, including influx and efflux of lipid molecules. The endoplasmic reticulum (ER) is the largest cellular membrane system and also the most metabolically active organelle responsible for lipid synthesis. However, how the nonequilibrium metabolic activity modulates ER membrane phase has not been investigated. Here, we studied the phase behavior of functional ER in the context of lipid metabolism. Utilizing advanced vibrational imaging technique, that is, stimulated Raman scattering microscopy, we discovered that metabolism of palmitate, a prevalent saturated fatty acid (SFA), could drive solid-like domain separation from the presumably uniformly fluidic ER membrane, a previously unknown phenomenon. The potential of various fatty acids to induce solid phase can be predicted by the transition temperatures of their major metabolites. Interplay between saturated and unsaturated fatty acids is also observed. Hence, our study sheds light on cellular membrane biophysics by underscoring the nonequilibrium metabolic status of living cell.


Assuntos
Retículo Endoplasmático/metabolismo , Microdomínios da Membrana/metabolismo , Animais , Células COS , Chlorocebus aethiops , Retículo Endoplasmático/ultraestrutura , Ácidos Graxos/metabolismo , Células HeLa , Humanos
12.
Small ; 14(16): e1704517, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29575525

RESUMO

Combining the advantage of metal, metal sulfide, and carbon, mesoporous hollow core-shell Sb/ZnS@C hybrid heterostructures composed of Sb/ZnS inner core and carbon outer shell are rationally designed based on a robust template of ZnS nanosphere, as anodes for high-performance sodium-ion batteries (SIBs). A partial cation exchange reaction based on the solubility difference between Sb2 S3 and ZnS can transform mesoporous ZnS to Sb2 S3 /ZnS heterostructure. To get a stable structure, a thin contiguous resorcinol-formaldehyde (RF) layer is introduced on the surface of Sb2 S3 /ZnS heterostructure. The effectively protective carbon layer from RF can be designed as the reducing agent to convert Sb2 S3 to metallic Sb to obtain core-shell Sb/ZnS@C hybrid heterostructures. Simultaneously, the carbon outer shell is beneficial to the charge transfer kinetics, and can maintain the structure stability during the repeated sodiation/desodiation process. Owing to its unique stable architecture and synergistic effects between the components, the core-shell porous Sb/ZnS@C hybrid heterostructure SIB anode shows a high reversible capacity, good rate capability, and excellent cycling stability by turning the optimized voltage range. This novel strategy to prepare carbon-layer-protected metal/metal sulfide core-shell heterostructure can be further extended to design other novel nanostructured systems for high-performance energy storage devices.

13.
Acc Chem Res ; 49(8): 1494-502, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27486796

RESUMO

Innovations in light microscopy have tremendously revolutionized the way researchers study biological systems with subcellular resolution. In particular, fluorescence microscopy with the expanding choices of fluorescent probes has provided a comprehensive toolkit to tag and visualize various molecules of interest with exquisite specificity and high sensitivity. Although fluorescence microscopy is currently the method of choice for cellular imaging, it faces fundamental limitations for studying the vast number of small biomolecules. This is because common fluorescent labels, which are relatively bulky, could introduce considerable perturbation to or even completely alter the native functions of vital small biomolecules. Hence, despite their immense functional importance, these small biomolecules remain largely undetectable by fluorescence microscopy. To address this challenge, a bioorthogonal chemical imaging platform has recently been introduced. By coupling stimulated Raman scattering (SRS) microscopy, an emerging nonlinear Raman microscopy technique, with tiny and Raman-active vibrational probes (e.g., alkynes and stable isotopes), bioorthogonal chemical imaging exhibits superb sensitivity, specificity, and biocompatibility for imaging small biomolecules in live systems. In this Account, we review recent technical achievements for visualizing a broad spectrum of small biomolecules, including ribonucleosides and deoxyribonucleosides, amino acids, fatty acids, choline, glucose, cholesterol, and small-molecule drugs in live biological systems ranging from individual cells to animal tissues and model organisms. Importantly, this platform is compatible with live-cell biology, thus allowing real-time imaging of small-molecule dynamics. Moreover, we discuss further chemical and spectroscopic strategies for multicolor bioorthogonal chemical imaging, a valuable technique in the era of "omics". As a unique tool for biological discovery, this platform has been applied to studying various metabolic processes under both physiological and pathological states, including protein synthesis activity of neuronal systems, protein aggregations in Huntington disease models, glucose uptake in tumor xenografts, and drug penetration through skin tissues. We envision that the coupling of SRS microscopy with vibrational probes would do for small biomolecules what fluorescence microscopy of fluorophores has done for larger molecular species.


Assuntos
Sondas Moleculares/metabolismo , Microscopia Óptica não Linear/métodos , Alcinos/química , Aminoácidos/metabolismo , Animais , Radioisótopos de Carbono , Deutério , Ácidos Graxos/metabolismo , Células HeLa , Humanos , Sondas Moleculares/química , Nucleosídeos/metabolismo , Proteínas/metabolismo , Vibração
14.
Anal Chem ; 87(13): 6937-44, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26043960

RESUMO

A new analytical method has been developed for speciation analysis of (127)I and (129)I in aerosols collected on polypropylene (PP) filter paper. Iodide, iodate, NaOH soluble iodine, and insoluble iodine were separated from aerosols using sequential extraction, chromatography separation, and alkaline ashing and measured using inductive coupled plasma mass spectrometry (ICP-MS) for (127)I and accelerator mass spectrometry (AMS) for (129)I. Parameters affecting the leaching efficiency and stability of iodine species, such as leaching time and temperature, amount of alkaline reagent for ashing, ashing temperature and time, and iodine protective agent, were investigated and optimized. It was observed that long time water leaching would change inorganic iodine species due to photochemical oxidation of iodide on the PP filter surface. NaOH leaching can only extract less than 60% of iodine from the studied aerosol filters even under heating, implying that total (129)I in aerosol might be underestimated by NaOH leaching. The addition of a reductive agent significantly reduced the loss of iodine during alkaline ashing from more than 35% to 4%, efficiently improving the separation efficiency of iodine in aerosols. Speciation analysis of (129)I and (127)I in aerosol samples collected at Risø, Denmark using the developed method shows that the measured values of total (129)I and (127)I are in good agreement with the sum of all iodine species for each isotope, confirming the reliability of the proposed method. Similar distribution patterns between (129)I and (127)I species show that iodine is enriched in NaOH leachable and insoluble species and depleted in water-soluble species, as observed in all aerosol samples.

15.
Environ Sci Technol ; 49(2): 1017-24, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25522224

RESUMO

Aerosol samples were collected from Tsukuba, Japan, soon after the 2011 Fukushima nuclear accident and analyzed for speciation of radiocesium and radioiodine to explore their chemical behavior and isotopic ratios after the release. Most (134)Cs and (137)Cs were bound in organic matter (53­91%) and some in water-soluble fractions (5­15%), whereas a negligible proportion of radiocesium remained in minerals. This pattern suggests that sulfate salts and organic matter may be the main carrier of Cs-bearing particles. The (129)I in aerosol samples is contained in various proportions as soluble inorganic iodine (I(­) and IO3(­)), soluble organic iodine, and unextractable iodine. The measured mean (129)I/(131)I atomic ratio of 16.0 ± 2.2 is in good agreement with that measured from rainwater and consistent with ratios measured in surface soil samples. Together with other aerosols and seawater samples, an initial (129)I/(137)Cs activity ratio of ∼4 × 10(­7) was obtained. In contrast to the effectively constant (134)Cs/(137)Cs activity ratios (1.04 ± 0.04) and (129)I/(131)I atomic ratios (16.0 ± 2.2), the (129)I/(137)Cs activity ratios scattered from 3.5 × 10(­7) to 5 × 10(­6) and showed temporally and spatially different dispersion and deposition patterns between radiocesium and radioiodine. These findings confirm that (129)I, instead of (137)Cs, should be considered as a proxy for (131)I reconstruction.


Assuntos
Poluentes Radioativos do Ar/análise , Radioisótopos de Césio/análise , Acidente Nuclear de Fukushima , Radioisótopos do Iodo/análise , Monitoramento de Radiação/métodos , Poluentes Radioativos do Solo/análise , Aerossóis , Japão
16.
Angew Chem Int Ed Engl ; 54(34): 9821-5, 2015 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-26207979

RESUMO

Glucose is a ubiquitous energy source for most living organisms. Its uptake activity closely reflects cellular metabolic demand in various physiopathological conditions. Extensive efforts have been made to specifically image glucose uptake, such as with positron emission tomography, magnetic resonance imaging, and fluorescence microscopy, but all have limitations. A new platform to visualize glucose uptake activity in live cells and tissues is presented that involves performing stimulated Raman scattering on a novel glucose analogue labeled with a small alkyne moiety. Cancer cells with differing metabolic activities can be distinguished. Heterogeneous uptake patterns are observed with clear cell-cell variations in tumor xenograft tissues, neuronal culture, and mouse brain tissues. By offering the distinct advantage of optical resolution but without the undesirable influence of fluorophores, this method will facilitate the study of energy demands of living systems with subcellular resolution.


Assuntos
Glucose/metabolismo , Glucose/farmacocinética , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Vibração , Animais , Sobrevivência Celular , Glucose/análogos & derivados , Células HeLa , Humanos , Camundongos , Análise Espectral Raman , Distribuição Tecidual
17.
J Stroke Cerebrovasc Dis ; 23(10): 2607-2613, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25287657

RESUMO

BACKGROUND: Many diseases include microRNAs (miRNAs) as reported biomarkers. The significance of circulating miRNAs for early diagnosis of acute stroke in humans is unknown. We aim to determine whether circulating miRNAs potentially serve as novel biomarkers for acute stroke. METHODS: We prospectively recruited patients with acute stroke and those with nonstroke disease. Patients with acute stroke were identified using magnetic resonance imaging (MRI) for early diagnosis. If the patient suffered from acute stroke that was detected with diffusion-weighted imaging, the patient was defined as an MRI(+) patient. Otherwise, it was defined as an MRI(-) patient. Circulating miRNAs were measured by miRNA microarray and real-time polymerase chain reaction (PCR) analysis. RESULTS: A total of 136 patients were included in the study. Testing by miRNA microarray and real-time PCR analyses showed that hsa-miR-106b-5P and hsa-miR-4306 were present with markedly high abundance in patients of acute stroke, whereas hsa-miR-320e and hsa-miR-320d were present with quite low abundance in patients compared with healthy individuals. Compared with healthy individuals, the miRNAs were increased as in patients with acute stroke as follows: hsa-miR-106b-5P, 3.63-fold in MRI(-) patients and 23.90-fold in MRI(+) patients; hsa-miR-4306, 3.19-fold in MRI(-) patients and 5.30-fold in MRI(+) patients; hsa-miR-320e, .33-fold in MRI(-) patients and .13-fold in MRI(+) patients; and hsa-miR-320d, .23-fold in MRI(-) patients and .07-fold in MRI(+) patients. CONCLUSIONS: Elevated hsa-miR-106b-5P and hsa-miR-4306 and decreased hsa-miR-320e and hsa-miR-320d in plasma may be novel biomarkers for the early detection of acute stroke in humans.


Assuntos
Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética , Diagnóstico Precoce , MicroRNAs/genética , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Humanos , Masculino , MicroRNAs/sangue , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/patologia
18.
Invest Ophthalmol Vis Sci ; 65(1): 19, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38190128

RESUMO

Purpose: Apolipoprotein A1 (APOA1) is a potential crucial protein and treatment goal for pathological myopia in humans. This study set out to discover the function of APOA1 in scleral remodeling in myopia and its underlying mechanisms. Methods: A myopic cell model was induced using hypoxia. Following loss- and gain-of function experiments, the expression of the myofibroblast transdifferentiation-related and collagen production-related factors Forkhead box M1 (FOXM1), APOA1, and methyltransferase-like 3 (METTL3) in the myopic cell model was examined by quantitative reverse transcription polymerase chain reaction (RT-qPCR) and western blotting. The proliferation and apoptosis were determined by Cell Counting Kit-8 assay and flow cytometry, respectively. Chromatin immunoprecipitation (ChIP) was employed to examine FOXM1 enrichment in the METTL3 promoter, methylated RNA immunoprecipitation (Me-RIP) to examine the N6-methyladenosine (m6A) modification level of APOA1, and photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation (PAR-CLIP) to examine the binding between METTL3 and APOA1. Results: Hypoxia-induced human scleral fibroblasts (HSFs) had high APOA1 and FOXM1 expression and low METTL3 expression. FOXM1 knockdown elevated METTL3 expression and downregulated APOA1 expression. FOXM1 was enriched in METTL3 promoter. APOA1 or FOXM1 knockdown or METTL3 overexpression reversed the hypoxia-induced elevation in vinculin, paxillin, and α-smooth muscle actin (α-SMA) levels and apoptosis and the reduction in collagen, type I, alpha 1 (COL1A1) level and cell proliferation in HSFs. METTL3 or YTH N6-methyladenosine RNA binding protein F2 (YTHDF2) knockdown or APOA1 overexpression reversed the impacts of FOXM1 knockdown on vinculin, paxillin, α-SMA, and COL1A1 expression and cell proliferation and apoptosis. Conclusions: FOXM1 elevated the m6A methylation level of APOA1 by repressing METTL3 transcription and enhanced APOA1 mRNA stability and transcription by reducing the YTHDF2-recognized m6A methylated transcripts.


Assuntos
Apolipoproteína A-I , Miopia Degenerativa , Humanos , Paxilina , Vinculina , Fatores de Transcrição , Hipóxia , Metiltransferases/genética , Proteína Forkhead Box M1/genética , Proteínas de Ligação a RNA
19.
Sci Total Environ ; 926: 171777, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38499094

RESUMO

The transport and deposition pathways of anthropogenic radionuclides at the global scale, particularly volatile 129I, remain somewhat elusive due to a dearth of comprehensive investigations. To gain a better understanding of the transport dynamics and deposition mechanism of anthropogenic 129I in the terrestrial environment, one hundred surface soil samples collected from northeast China were analyzed for 129I and 127I concentrations in this study. Our findings reveal that 129I/127I atomic ratios in the mid-eastern Inner Mongolia (MIM) were approximately an order of magnitude higher than the rest of the investigated area. This is, besides the global fallout and the long-range transport of 129I released from the European nuclear reprocessing plants via westerly winds, possibly attributed to the dust with high 129I levels from the East Asian arid regions. In addition to the significant dust-induced 129I input, the unique meteorological conditions and topographical features in the MIM synergistically contribute to the pronounced accumulation and deposition of 129I in this region. This study will provide novel insights into the transport and deposition mechanism of anthropogenic radionuclides, which is significant for the assessment of anthropogenic nuclear activities on the environment in the future.

20.
J Hazard Mater ; 465: 133095, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38056270

RESUMO

In recent years, various materials have been used to adsorb and remove perfluoroalkyl compounds from water. However, most of these materials have limited applications due to their high cost, complex synthesis, inadequate selectivity and sensitivity, and, even worse, the possibility of introducing secondary pollution. Here, under mild conditions, we prepared an inexpensive imidazolium chloride and nitrogen-rich polymer (TAGX-Cl) with a high cationic loading rate and a high yield (>82%). The adsorbent exhibits excellent pH tolerance (pH=1-9) and achieves nearly 99.9% removal of nine perfluoroalkyl carboxylic acids (PFCAs) within 120 min. Experimental data and theoretical simulations confirmed that synergistic electrostatic interactions, hydrogen bonds, and P-π interactions control the adsorptive ability of TAGX-Cl. This work provides a practical strategy for PFCAs removal.

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