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1.
Anal Chem ; 96(6): 2514-2523, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38289041

RESUMO

The urine bioassay method for transuranium nuclides (237Np, 239,240,241Pu, 241Am, and 244Cm) is needed to quickly assess the potential internal contamination in emergency situations. However, in the case that the analysis of multiple radionuclides is required in the same sample, time-consuming/tedious sequential analytical procedures using multiple chromatographic separation resins would have to be employed for the separation of every single radionuclide. In this work, a rapid method for the simultaneous determination of transuranium nuclides in urine was developed by using triple quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS) combined with a single DGA resin column. The chemical behaviors of Np/Pu and Am/Cm on the DGA resin were consistent in 8-10 mol/L HNO3 and 0.005-0.02 mol/L NaNO2 when 242Pu and 243Am were selected as tracers for Np/Pu and Am/Cm yield monitoring. Based on their different reaction rates with O2, 237Np, 239,240,241Pu, 241Am, and 244Cm in the same solution were simultaneously measured by ICP-MS/MS in the same run. The elimination efficiency of 238U+ tailing (7.43 × 10-9), 238U1H16O2+/238U16O2+ (8.11 × 10-8) and cross contamination of 241Pu and 241Am (<1%) were achieved using 10.0 mL/min He-0.3 mL/min O2 even if the eluate was directly measured without any evaporation. The detection limits of transuranium nuclides were at the femtogram level, demonstrating the feasibility of ICP-MS/MS for simultaneous transuranic radionuclides urinalysis. The developed method was validated by analyzing the spiked urine samples.


Assuntos
Radioisótopos , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Radioisótopos/análise , Análise Espectral , Cromatografia , Urinálise
2.
Environ Sci Technol ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958591

RESUMO

As the number of coastal nuclear facilities rapidly increases and the wastewater from the Fukushima Nuclear Plant has been discharged into the Pacific Ocean, the nuclear environmental safety of China's marginal seas is gaining increased attention along with the heightened potential risk of nuclear accidents. However, insufficient work limits our understanding of the impact of human nuclear activities on the Yellow Sea (YS) and the assessment of their environmental process. This study first reports the 129I and 127I records of posthuman nuclear activities in the two YS sediments. Source identification of anthropogenic 129I reveals that, in addition to the gaseous 129I release and re-emission of oceanic 129I discharged from the European Nuclear Fuel Reprocessing Plants (NFRPs), the Chinese nuclear weapons testing fallout along with the global fallout is an additional 129I input for the continental shelf of the YS. The 129I/127I atomic ratios in the North YS (NYS) sediment are significantly higher than those in the other adjacent coastal areas, attributed to the significant riverine input of particulate 129I by the Yellow River. Furthermore, we found a remarkable 129I latitudinal disparity in the sediments than those in the seawaters in the various China seas, revealing that sediments in China's marginal seas already received a huge anthropogenic 129I from terrigenous sources via rivers and thus became a significant sink of anthropogenic 129I. This study broadens an insight into the potential impacts of terrigenous anthropogenic pollution on the Chinese coastal marine radioactive ecosystem.

3.
Anal Chem ; 95(34): 12931-12939, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37590167

RESUMO

As the most important plutonium isotopes, 238Pu, 239Pu, 240Pu, and 241Pu are normally measured by two to three techniques, which are tedious, time-consuming, and not suitable for rapid analysis in emergency situations. Recently, ICP-MS has become a competitive technique for the rapid measurement of 239Pu, 240Pu, and 241Pu. However, ICP-MS is difficult to measure 238Pu due to the serious isobaric interference of 238U. This work reports a rapid analytical method to solve this problem for the simultaneous determination of 238Pu, 239Pu, 240Pu, and 241Pu using triple-quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS) combined with chemical separation. Chemical separation achieved a high decontamination factor of 2.12 × 109 for the most critical interfering element, uranium, by using two sequential TK200 columns. The interferences of 238U1H+ and 238U+ were effectively eliminated by using 12 mL/min He-6 mL/min NH3 as the reaction gases in the octupole collision/reaction cell in ICP-MS/MS. Combined with chemical separation, the overall elimination efficiency of 238U1H+ reached 3.6 × 1017, which is 105 times better than the reported method. With the high 238U+ elimination efficiency of 1.12 × 104 in the ICP-MS/MS measurement, the overall removal efficiency of 238U+ reached 1013, guaranteeing accurate determination of femtogram-level 238Pu as well as 239Pu, 240Pu, and 241Pu in the samples containing milligram-level 238U. The detection time is reduced to minutes, well fulfilling the requirement of rapid analysis. This method is validated by analyzing the standard reference material and the spiked samples.

4.
Anal Chem ; 95(7): 3647-3655, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36763009

RESUMO

Accelerator mass spectrometry (AMS) is one of the most sensitive techniques used to measure the long-lived actinides. This is particularly of interest for determination of ultra-trace transuranium nuclides and their isotopic fingerprints for nuclear forensics. In this work, a new method was developed for simultaneous determination of transuranium nuclides (Np, Pu, Am, and Cm isotopes) by using 300 kV AMS after a sequential chemical separation of each group of actinides. 242Pu and 243Am were utilized as tracers for Np/Pu and Am/Cm yield monitoring. The results show that the chemical behaviors of Np and Pu on the TK200 column and those of Am and Cm on the DGA column were very consistent in 8-9 mol/L of HNO3 and 0.015-0.03 mol/L of NaNO2 media during the radiochemical separation. The AMS detection efficiencies for transuranium nuclides were also evaluated. The detection limits for all radionuclides are below femtogram level and even in attogram level for Pu and Cm isotopes. The established method has been successfully applied to accurately measure various transuranium nuclides in a single actinide radionuclide solution, demonstrating its feasibility for nuclear forensic investigation.

5.
Environ Sci Technol ; 57(27): 10070-10078, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37366000

RESUMO

Anthropogenic 129I, as a long-lived fission product and volatile radionuclide, can be used to investigate dispersion of air masses and the deposition of atmospheric pollution. Surface soil and soil core samples were collected from Northern Xinjiang and analyzed for 127I and 129I. The results show that 129I/127I atomic ratios in surface soil are inhomogeneous with a range of (2.07-106) × 10-9, and the maximum values in each soil core occurred at surface-subsurface layers (0-15 cm) at undisturbed sites. The dominant source of 129I in Northern Xinjiang is European nuclear fuel reprocessing plant (NFRP) releases, accounting for at least 70% of the total inventory; less than 20% of 129I originates from the global fallout of atmospheric nuclear weapons tests; less than 10% comes from the regional deposition of nuclear weapons tests at the Semipalatinsk site; and the regional deposition from the nuclear weapons tests at the Lop Nor site is insignificant. The European NFRP-derived 129I was transported to Northern Xinjiang via long-distance atmospheric dispersion with the westerlies through Northern Eurasia. The distribution of 129I in the surface soil in Northern Xinjiang is mainly controlled by topography, wind fields, land utilization, and vegetation coverage.


Assuntos
Radioisótopos do Iodo , Poluentes Radioativos da Água , China , Radioisótopos do Iodo/análise , Poluentes Radioativos da Água/análise , Solo
6.
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
7.
Neurosurg Rev ; 46(1): 280, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37875636

RESUMO

Extracerebral tumors often occur on the surface of the brain or at the skull base. It is important to identify the peritumoral sulci, gyri, and nerve fibers. Preoperative visualization of three-dimensional (3D) multimodal fusion imaging (MFI) is crucial for surgery. However, the traditional 3D-MFI brain models are homochromatic and do not allow easy identification of anatomical functional areas. In this study, 33 patients with extracerebral tumors without peritumoral edema were retrospectively recruited. They underwent 3D T1-weighted MRI, diffusion tensor imaging (DTI), and CT angiography (CTA) sequence scans. 3DSlicer, Freesurfer, and BrainSuite were used to explore 3D-color-MFI and preoperative planning. To determine the effectiveness of 3D-color-MFI as an augmented reality (AR) teaching tool for neurosurgeons and as a patient education and communication tool, questionnaires were administered to 15 neurosurgery residents and all patients, respectively. For neurosurgical residents, 3D-color-MFI provided a better understanding of surgical anatomy and more efficient techniques for removing extracerebral tumors than traditional 3D-MFI (P < 0.001). For patients, the use of 3D-color MFI can significantly improve their understanding of the surgical approach and risks (P < 0.005). 3D-color-MFI is a promising AR tool for extracerebral tumors and is more useful for learning surgical anatomy, developing surgical strategies, and improving communication with patients.


Assuntos
Realidade Aumentada , Neoplasias , Humanos , Imagem de Tensor de Difusão , Estudos Retrospectivos , Imageamento Tridimensional/métodos
8.
J Obstet Gynaecol Res ; 49(1): 128-140, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36288911

RESUMO

AIM: Preeclampsia (PE) is a common medical complication of pregnancy characterized by high blood pressure and proteinuria after the 20th gestational week. This study aimed to investigate the potency of the combination of curcumin and aspirin in the treatment of PE and explore the underlying mechanisms. MATERIAL AND METHODS: The PE model was constructed in female rats by administering 0.5 mg/mL N-nitro-L-arginine methyl ester from gestational days (GDs) 6 to 16. The pregnant female rats were divided into five groups according to the drug treatment. The curcumin or aspirin was given to the rats by tail vein injection (0.36 mg/kg) or gavage treatment (1.5 mg/kg BW/day) from GD4 to GD18. RESULTS: Treatment with curcumin and aspirin combination significantly reduced the systolic blood pressure and proteinuria in the PE rats. Meanwhile, in comparison to the PE rats treated with single-dose curcumin or aspirin, the rats treated with combined curcumin and aspirin showed significantly decreased sFlt-1, increased placental growth factor, and alleviated oxidative stress in both blood and placental tissues, which are abnormal in no-treated PE rats. Furthermore, dramatically decreased inflammatory cytokines secretion and TLR4 and NF-κB p65 expression in placental tissues were also observed in the PE rats with combined treatment compared to those of no-treated, signal-dose curcumin or aspirin-treated PE rats. CONCLUSIONS: Our results suggested that the combined treatment of curcumin and aspirin significantly ameliorates the symptoms of PE in rats, which is most likely due to the inhibition of the placental TLR4/NF-κB p65 signaling pathway.


Assuntos
Curcumina , Pré-Eclâmpsia , Humanos , Ratos , Feminino , Gravidez , Animais , Aspirina/farmacologia , Aspirina/uso terapêutico , NF-kappa B/metabolismo , Placenta/metabolismo , Curcumina/farmacologia , Curcumina/metabolismo , Curcumina/uso terapêutico , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/uso terapêutico , Fator de Crescimento Placentário/metabolismo , Transdução de Sinais , Proteinúria/tratamento farmacológico
9.
J Stroke Cerebrovasc Dis ; 32(8): 107192, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37216751

RESUMO

BACKGROUND: Decreased organ function and poor physical compensatory capacity in elderly patients diagnosed with spontaneous intracerebral hemorrhage (ICH) can make surgical treatment procedures challenging and risky. Minimally invasive puncture drainage (MIPD) combined with urokinase infusion therapy is a safe and feasible method of treating ICH. This study aimed to compare the treatment efficacy of MIPD conducted under local anesthesia using either 3DSlicer + Sina application or computer tomography (CT)-guided stereotactic localization of hematomas in elderly patients diagnosed with ICH. METHODS: The study sample included 78 elderly patients (≥ 65 years of age) diagnosed with ICH for the first time. All patients exhibited stable vital signs and underwent surgical treatment. The study sample was randomly divided into two groups, either receiving 3DSlicer+Sina or CT-guided stereotactic assistance. The preoperative preparation time; hematoma localization accuracy rate; satisfactory hematoma puncture rate; hematoma clearance rate; postoperative rebleeding rate; Glasgow Coma Scale (GCS) score after 7 days; and modified Rankin scale (mRS) score 6 months after surgery were compared between the two groups. RESULTS: No significant differences in gender, age, preoperative GCS score, preoperative hematoma volume (HV), and surgical duration were observed between the two groups (all p-values > 0.05). However, the preoperative preparation time was shorter in the group receiving 3DSlicer + Sina assistance compared to that receiving CT-guided stereotactic assistance (p-value < 0.001). Both groups exhibited significant improvement in GCS scores and reduction in HV after surgery (all p-values < 0.001). The accuracy of hematoma localization and puncture was 100% in both groups. There were no significant differences in surgical duration, postoperative hematoma clearance rate, rebleeding rate, postoperative GCS and mRS scores between the two groups (all p-values > 0.05). CONCLUSIONS: A combination of 3DSlicer and Sina is effective in accurately identifying hematomas in elderly patients with ICH exhibiting stable vital signs, thus simplifying MIPD surgeries conducted under local anesthesia. This procedure may also be preferred over CT-guided stereotactic localization in clinical practice due to its ease of use and accuracy in hematoma localization.


Assuntos
Anestesia Local , Hemorragia Cerebral , Idoso , Humanos , Anestesia Local/efeitos adversos , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/cirurgia , Drenagem/efeitos adversos , Hematoma/diagnóstico por imagem , Hematoma/etiologia , Hematoma/cirurgia , Punções
10.
Anal Chem ; 94(31): 10959-10966, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35878318

RESUMO

For efficient and accurate speciation analysis of 129I in the nitric acid solution of spent nuclear fuel in its reprocessing process, a sequential procedure for stepwise separation of different iodine species in 3 mol/L HNO3 was proposed based on the solvent extraction using CCl4 and mesitylene. Molecular iodine (I2) was first separated by solvent extraction using CCl4, and iodide (I-) remaining in the aqueous phase was oxidized to I2 by adding NaNO2 and then extracted to mesitylene. Finally, iodate (IO3-) was reduced to I2 using NH2OH·HCl and extracted to mesitylene. The separation efficiency of 98-99% for tracer amounts of 129I2, 129I-, and 129IO3- in 3 mol/L HNO3 and less than 2% crossover among different iodine species were achieved. The extraction process and mechanism of different iodine species in CCl4 and mesitylene were investigated, and the problem of crossover of different iodine species due to the low extraction efficiency of low concentration of iodine in nitric acid solution was solved. A direct transfer of IO3- from HNO3 to the mesitylene phase without conversion to I2 was observed, which was attributed to the iodination of mesitylene in the HNO3 medium. Addition of a stable iodine species carrier and repeated extraction significantly improved the separation efficiency of iodine species, making their quantitative separation achievable. This method provides an approach for speciation analysis of 129I in the acidic spent nuclear fuel solution, enabling us to investigate and control the behavior of volatile 129I in the spent nuclear fuel reprocessing process.


Assuntos
Iodetos , Iodo , Radioisótopos do Iodo , Ácido Nítrico , Solventes
11.
Anal Chem ; 94(33): 11582-11590, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35948028

RESUMO

93Mo is an important radionuclide in view of radioactive waste repository because of its long half-life and high mobility in the environment. 93Mo decays by electron capture without any measurable gamma ray emission. The concentration of 93Mo in most of the radioactive waste is many orders of magnitude lower than the major activation product radionuclides, which makes the accurate determination of 93Mo a big challenge. A new analytical method for the determination of 93Mo in sulfuric acid media from nuclear power reactor was developed. 93Mo was separated from most of the radionuclides by cation exchange chromatography followed by the removal of sulfate by CaSO4 precipitation. A further purification of 93Mo, especially from anion species of 51Cr and 125Sb, was achieved by anion exchange chromatography and a short alumina column separation. The chemical yield of 93Mo in the entire separation procedure reached about 75%, and the decontamination factors for all potential interfering radionuclides were 1.5 × 106-1.6 × 108. The purified 93Mo was measured by liquid scintillation counting through counting its low-energy Auger electrons. A detection limit of 2 mBq/g for 93Mo in 50 g sample was achieved by this method, which enables the quantitative determination of 93Mo in most of the radioactive samples in the decommissioning waste and coolant water of nuclear power reactors. The developed method has been successfully applied to determine 93Mo in coolant water of nuclear power reactors, providing a robust analytical approach of 93Mo for the radiological characterization of radioactive wastes.


Assuntos
Resíduos Radioativos , Ânions/análise , Resíduos Radioativos/análise , Radioisótopos , Ácidos Sulfúricos , Água/análise
12.
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
13.
Microb Pathog ; 162: 105352, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34883226

RESUMO

Avian infectious bronchitis (IB) was caused by infectious bronchitis virus (IBV), a coronavirus, which leads to enormous economic losses in the poultry industry. Studies have shown that lithium chloride (LiCl) is a good virus inhibitor. Through cell culture, virus infection, and RT-qPCR, we found that LiCl could down-regulate the apoptosis-related genes Caspase-3 and Bax, up-regulate Bcl-2, and down-regulate the inflammatory-related genes (NF-κB, NLRP3, TNF-α, and IL-1ß) via inhibiting virus replication. Finally, clinical trials showed that LiCl could inhibit IBV-induced apoptosis and inflammatory in chicken embryos as well as reduce the mortality and deformity rate of chicken embryos. The results showed that LiCl has antiviral activity against IBV and clinical effects. Further studies are required to explore the exact action mechanism of LiCl on IBV-induced apoptosis and inflammation.


Assuntos
Vírus da Bronquite Infecciosa , Doenças das Aves Domésticas , Animais , Apoptose , Embrião de Galinha , Galinhas , Inflamação/tratamento farmacológico , Cloreto de Lítio/farmacologia , Doenças das Aves Domésticas/tratamento farmacológico
14.
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
15.
Molecules ; 27(14)2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35889408

RESUMO

The determination of 241Am in the environment is of importance in monitoring its release and assessing its environmental impact and radiological risk. This paper aims to give an overview about the recent developments and the state-of-art analytical methods for 241Am determination in environmental samples. Thorough discussions are given in this paper covering a wide range of aspects, including sample pre-treatment and pre-concentration methods, chemical separation techniques, source preparation, radiometric and mass spectrometric measurement techniques, speciation analyses, and tracer applications. The paper focuses on some hyphenated separation methods based on different chromatographic resins, which have been developed to achieve high analytical efficiency and sample throughput for the determination of 241Am. The performances of different radiometric and mass spectrometric measurement techniques for 241Am are evaluated and compared. Tracer applications of 241Am in the environment, including speciation analyses of 241Am, and applications in nuclear forensics are also discussed.


Assuntos
Radiometria , Espectrometria de Massas/métodos , Radiometria/métodos
16.
Anal Chem ; 93(7): 3362-3369, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33550799

RESUMO

Our recent attempt to determine ultratrace-level 236U and 233U in small-volume seawater samples was challenged by high and unstable procedure blanks in our environmental radioactivity laboratory, which used to be a spent fuel research facility. Through intercomparison experiments with different laboratories and background checks on the chemical reagents and laboratory dust, the resuspended U-bearing dust was identified as the dominating source of the 236U and 233U contamination. With the implementation of background control (especially dust control) measures, the procedure blanks and detection limits of 236U and 233U for the radiochemical separation procedure have been significantly improved by three orders of magnitudes. With well-controlled blanks, the analytical precision for 236U and 233U predominantly relies on the AMS counting statistics. Background check and dust control are strongly recommended before the analyses of environmental-level long-lived radionuclides (such as 236U and 233U) that are conducted in the former or active nuclear facilities, even if clearance of radioactivity relevant for radioprotection was achieved.

17.
Nutr Cancer ; 73(6): 1040-1046, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32586129

RESUMO

Colorectal cancer (CRC) is the third most cancer-related death worldwide. This work aimed to identify potential hub genes and dysregulated pathways in the CRC by bioinformatics analysis. Three gene expression datasets were collected from GEO datasets, including tumor sample (N = 242) and adjacent nontumor tissue sample (N = 59). RankProd was used to discover the differential expressed genes between tumor and adjacent nontumor tissues for datasets generated by different laboratories. The gene set enrichment analysis conducted on the DE genes, followed by the protein-protein interaction (PPI) network. In total, 2,007 significant differential expression (DE) genes between tumor and adjacent nontumor tissues, include 1,090 upregulated genes and 917 downregulated genes in the tumor. The DE mRNAs are involved in cancer-related pathways. We comprehensively identified the CRC-related key mRNAs. Our data demonstrated combined different resources of transcriptomes will promote the understanding of the molecular mechanisms underlying CRC development and may be useful in discovering candidate molecular biomarkers for diagnosing, prognosis, and treating of CRC.


Assuntos
Neoplasias Colorretais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/genética , Biologia Computacional , Regulação Neoplásica da Expressão Gênica , Humanos , Mapas de Interação de Proteínas , RNA Mensageiro/genética , Transcriptoma
18.
Environ Sci Technol ; 55(13): 8918-8927, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34105953

RESUMO

A strongly stratified water structure and a densely populated catchment make the Baltic Sea one of the most polluted seas. Understanding its circulation pattern and time scale is essential to predict the dynamics of hypoxia, eutrophication, and pollutants. Anthropogenic 236U and 233U have been demonstrated as excellent transient tracers in oceanic studies, but unclear input history and inadequate long-term monitoring records limit their application in the Baltic Sea. From two dated Baltic sediment cores, we obtained high-resolution records of anthropogenic uranium imprints originating from three major human nuclear activities throughout the Atomic Era. Using the novel 233U/236U signature, we distinguished and quantified 236U inputs from global fallout (45.4-52.1%), Chernobyl accident (0.3-1.8%), and discharges from civil nuclear industries (46.1-54.3%) to the Baltic Sea. We estimated the total release of 233U (7-15 kg) from the atmospheric nuclear weapon testing and pinpointed the 233U peak signal in the mid-to-late 1950s as a potential time marker for the onset of the Anthropocene Epoch. This work also provides fundamental 236U data on Chernobyl accident and early discharges from civil nuclear facilities, prompting worldwide 233U-236U tracer studies. We anticipate our data to be used in a broader application in model-observation interdisciplinary research on water circulation and pollutant dynamics in the Baltic Sea.


Assuntos
Urânio , Poluentes Radioativos da Água , Países Bálticos , Sedimentos Geológicos , Humanos , Oceanos e Mares , Urânio/análise , Poluentes Radioativos da Água/análise
19.
Mol Biol Rep ; 48(1): 595-600, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33394235

RESUMO

We previously reported that Numb, a protein localized to clathrin-coated vesicles, regulates the membrane expression of metabotropic glutamate receptor 5 (mGluR5) and is critical to social behaviors. However, the distinct actions of Numb isoforms on mGluR5 have not been investigated. Here, we showed that the expression patterns of Numb-p72 and Numb-p65, two important isoforms of Numb, were distinct in HEK293T cells. Numb-p72, but not Numb-p65, bound to mGluR5α, and enhanced mGluR5 membrane expression by inhibiting its internalization. Our results suggest that a complete structure is required for Numb to bind to mGluR5 and to modulate mGluR5 trafficking.


Assuntos
Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Transporte Proteico/genética , Receptor de Glutamato Metabotrópico 5/genética , Movimento Celular/genética , Células HEK293 , Hipocampo/metabolismo , Humanos , Neurônios/metabolismo , Ligação Proteica/genética , Isoformas de Proteínas/genética
20.
Metab Brain Dis ; 36(8): 2461-2472, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34436746

RESUMO

Cerebral ischemia/reperfusion (I/R) injury remains a leading cause of death and disability. Long noncoding RNAs (lncRNAs) exert key functions in cerebral I/R injury. Here, we sought to elucidate the mechanism underlying the regulation of H19 in cerebral I/R cell injury. An in vitro model of cerebral I/R injury was created using oxygen-glucose deprivation/reoxygenation (OGD/R). The levels of H19, miR-1306-5p and B cell lymphoma-2 (Bcl-2)-like 13 (BCL2L13) were assessed by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. Cell viability and apoptosis were determined by the Cell Counting-8 Kit (CCK-8) assay and flow cytometry, respectively. The levels of lactate dehydrogenase (LDH) and cytokines were evaluated by enzyme-linked immunosorbent assays (ELISA). Direct relationships among H19, miR-1306-5p and BCL2L13 were verified by dual-luciferase reporter, RNA immunoprecipitation (RIP) and RNA pulldown assays. Our data showed that H19 and BCL2L13 were highly expressed in the cerebral I/R injury rats and OGD/R-triggered SK-N-SH and IMR-32 cells. The knockdown of H19 or BLC2L13 alleviated OGD/R-triggered injury in SK-N-SH and IMR-32 cells. Moreover, H19 silencing protected against OGD/R-triggered cell injury by down-regulating BCL2L13. H19 acted as a sponge of miR-1306-5p and BCL2L13 was a direct target of miR-1306-5p. H19 mediated BCL2L13 expression by sequestering miR-1306-5p. Furthermore, miR-1306-5p was a molecular mediator of H19 function. These results suggested that H19 silencing alleviated OGD/R-triggered I/R injury at least partially depending on the regulation of the miR-1306-5p/BCL2L13 axis.


Assuntos
MicroRNAs , RNA Longo não Codificante , Traumatismo por Reperfusão , Animais , Apoptose/genética , Glucose , MicroRNAs/genética , MicroRNAs/metabolismo , Oxigênio , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ratos , Traumatismo por Reperfusão/metabolismo
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