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1.
Cell Biol Toxicol ; 40(1): 22, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38630149

ABSTRACT

Uremic encephalopathy (UE) poses a significant challenge in neurology, leading to the need to investigate the involvement of non-coding RNA (ncRNA) in its development. This study employed ncRNA-seq and RNA-seq approaches to identify fundamental ncRNAs, specifically circRNA and miRNA, in the pathogenesis of UE using a mouse model. In vitro and in vivo experiments were conducted to explore the circRNA-PTPN4/miR-301a-3p/FOXO3 axis and its effects on blood-brain barrier (BBB) function and cognitive abilities. The research revealed that circRNA-PTPN4 binds to and inhibits miR-301a-3p, leading to an increase in FOXO3 expression. This upregulation results in alterations in the transcriptional regulation of ZO-1, affecting the permeability of human brain microvascular endothelial cells (HBMECs). The axis also influences the growth, proliferation, and migration of HBMECs. Mice with UE exhibited cognitive deficits, which were reversed by overexpression of circRNA-PTPN4, whereas silencing FOXO3 exacerbated these deficits. Furthermore, the uremic mice showed neuronal loss, inflammation, and dysfunction in the BBB, with the expression of circRNA-PTPN4 demonstrating therapeutic effects. In conclusion, circRNA-PTPN4 plays a role in promoting FOXO3 expression by sequestering miR-301a-3p, ultimately leading to the upregulation of ZO-1 expression and restoration of BBB function in mice with UE. This process contributes to the restoration of cognitive abilities.


Subject(s)
Blood-Brain Barrier , Cognition , Forkhead Box Protein O3 , MicroRNAs , RNA, Circular , Humans , Brain Diseases , Endothelial Cells , Forkhead Box Protein O3/genetics , Forkhead Box Protein O3/metabolism , MicroRNAs/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 4 , RNA, Circular/genetics
2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 31(1): 179-182, 2023 Feb.
Article in Chinese | MEDLINE | ID: mdl-36765496

ABSTRACT

OBJECTIVE: To explore the carrier rate, genotype and phenotype of α-thalassemia fusion gene in Huadu district of Guangzhou, Guangdong province of China, and provide data reference for the prevention and control of thalassemia. METHODS: A total of 10 769 samples who were screened for thalassemia in Maternal and Child Health Hospital of Huadu District from July 2019 to November 2020 were analyzed retrospectively. Blood cell analysis and hemoglobin (Hb) electrophoresis were performed. Thalassemia genes were analyzed by gap-PCR and PCR-reverse dot blot hybridization (PCR-RDB). RESULTS: A total of 9 cases with α-thalassemia fusion gene were detected in 10 769 samples (0.08%). There were 7 cases with fusion gene heterozygote, 1 case with compound of α-thalassemia fusion gene and Hb G-Honolulu, 1 case with compound of α-thalassemia fusion gene and Hb QS. The MCV results of 4 samples of blood cell analysis were within the reference range, the Hb A2 value of 1 case was decreased, and there were no other abnormalities found. CONCLUSION: The α-thalassemia fusion gene is common in Huadu district of Guangzhou, and heterozygotes are more common, and current screening methods easily lead to misdiagnosis.


Subject(s)
alpha-Thalassemia , beta-Thalassemia , Humans , alpha-Thalassemia/genetics , Retrospective Studies , beta-Thalassemia/genetics , Genotype , Phenotype , Heterozygote , China , Mutation
3.
Sci Total Environ ; 783: 146982, 2021 Aug 20.
Article in English | MEDLINE | ID: mdl-33866170

ABSTRACT

The occurrence of mutagenic and carcinogenic N-nitrosamines in drinking water is of great concern. In this study, dynamics and removal of nine N-nitrosamines in three drinking water treatment systems of a southern city of China are monitored during one year of sampling. The impacts of physicochemical treatment units on the removal and generation of N-nitrosamines were evaluated. The O3 and KMnO4 based pre-oxidation units have caused an increase in N-nitrosamines concentration, with O3 showing the substantial generation of N-nitrosamines. The carbon filter and ultrafiltration membrane units were found effective in removing N-nitrosamine precursors. These drinking water treatment systems have been useful in removing N-nitrosamine precursors; meanwhile, a slight decrease was found in already formed N-nitrosamines concentration. However, N-nitrosomorpholine (NMOR) and N-nitrosodiphenylamine (NDPhA) were found resistant toward all kinds of physicochemical treatments, and negligible changes in concentration were noted in all drinking water treatment systems. The distribution networks in the city provided an effective contact period to residual chlorine and precursors, which caused an increase in N-nitrosamines concentration. Overall, N-nitrosodimethylamine (NDMA) and N-nitroso-diethylamine (NDEA) have been found near the cancer risk threshold (10-6) in all of the drinking water treatment systems, while the remaining seven N-nitrosamines were found below the risk level.


Subject(s)
Drinking Water , Nitrosamines , Water Pollutants, Chemical , Water Purification , China , Drinking Water/analysis , Nitrosamines/analysis , Renal Dialysis , Water Pollutants, Chemical/analysis
4.
Sci Total Environ ; 771: 144850, 2021 Jun 01.
Article in English | MEDLINE | ID: mdl-33548702

ABSTRACT

Delivering drinking water with stable quality in metropolitan cities is a big challenge. This study investigated the year-long dynamics of dissolved organic matter (DOM) in the tap water and source water of a metropolitan city in southern China using fluorescence spectroscopy. The DOM detected in the tap water, and source water of Shenzhen city was season and location-dependent. A year-long cyclic trend of DOM was found with predominate protein-like fluorescence in the dry season compared to the humic-like enriched DOM in the wet season. A general DOM pattern was estimated by measuring the shift in dominant fluorescence regions on the excitation-emission matrix (EEM). The difference in fluorescent DOM (FDOM) composition (in terms of the ratio of protein-like to humic-like fluorescence) was above 200% between wet and dry seasons. The taps associated with reservoirs receiving water from the eastern tributary of Dongjiang River showed significant changes in protein-like contents than the taps with source water originating from the western part of the river. This study highlights the importance of optimizing drinking water treatment plants' operational conditions after considering seasonal changes and source water characteristics.


Subject(s)
Humic Substances , Rivers , China , Cities , Humic Substances/analysis , Spectrometry, Fluorescence , Water
5.
Sci Total Environ ; 771: 145409, 2021 Jun 01.
Article in English | MEDLINE | ID: mdl-33548708

ABSTRACT

The presence of carcinogenic N-nitrosamines and dissolved organic matter (DOM) in freshwater is a significant concern from the perspective of public health and drinking water treatment plant operation. This study investigated the N-nitrosamines concentration and their precursors' distributions, and DOM composition in four reservoirs located in a southern city of China. A total of 22 renowned precursors were identified. Precursors from industrial and pharmaceutical origins were found to be dominant in all reservoirs; however, traces of pesticide-based precursors, i.e. pirimicarb and cycluron were also found. The distribution of nine N-nitrosamines was substantially different among the reservoirs. N-Nitrosodibutylamine (NDBA), N-Nitrosopiperidine (NPIP), N-Nitrosodimethylamine (NDMA), and N-Nitrosopyrrolidine (NPYR) were abundantly present in all reservoirs. Most of N-nitrosamines except NDMA and N-nitrosodiethylamine (NDEA) were far below the generally accepted cancer risk of 10-6, and NDMA/NDEA were found close to the risk level (10-6). Anthropogenic DOM was dominant in three reservoirs as depicted by a higher biological index (BIX) than the humification index (HIX). By the principle component analysis, BIX appeared as an indicator of N-nitrosamines (except NDEA and NPIP). A strong and direct relationship was observed between the NDMA-formation potential (FP) and concentration of total N-nitrosamines (∑NA), and BIX. These results confirmed that the anthropogenic activities were the leading source of DOM and N-nitrosamines in this city based on land-use.

6.
Water Res ; 183: 116125, 2020 Sep 15.
Article in English | MEDLINE | ID: mdl-32650297

ABSTRACT

This study aims to extend and demonstrate the application of fluorescence spectroscopy for monitoring the water quality of three differently operated full-scale drinking water treatment plants located in the Shenzhen city (China). A ratio of fluorescent dissolved organic matter (FDOM), which describes relative changes in humic-like to protein-like fluorescence, was used to explain mechanisms behind the physicochemical processes. The fluorescence components obtained through individual and combined parallel factor analysis (PARAFAC) modeling revealed the presence of humic-like (C1) and protein-like (C2) structures in the DOM. The C1/C2 ratio provided a direct relationship between the seasonal variations and DOM composition. Wet season generated DOM enriched with humic-like fluorescence, while dry season caused a higher release of protein-like fluorescence. The fluorescence ratio presented unique patterns of DOM in treatment trains. The chemical pretreatment and disinfection unit processes showed a higher tendency to remove the humic-like fluorescence. However, the C1/C2 ratio increased during physical treatment processes such as coagulation-precipitation and sand filtration, indicating preferential removal of protein-like fluorescence. The DOM composition in influent directly (R2 = 0.77) influenced the relative intensities of fluorescence components in the treated water. Compared to the dry season, the wet season caused significant changes in DOM composition and produced treated water enriched with humic-like fluorescence. This fluorescence ratio offers an approach to explore the role of different treatment units and determine the factors affecting the composition of DOM in the surface water and drinking water treatment plants.


Subject(s)
Drinking Water/analysis , Water Purification , China , Factor Analysis, Statistical , Humic Substances/analysis , Spectrometry, Fluorescence , Water Quality
7.
Water Res ; 183: 116096, 2020 Sep 15.
Article in English | MEDLINE | ID: mdl-32717651

ABSTRACT

N-nitrosamines have been identified as emerging contaminants with tremendous carcinogenic potential for human beings. This study examined the seasonal changes in the occurrence of N-nitrosamines and N-nitrosodimethylamine formation potential (NDMA-FP) in drinking water resources and potable water from 10 drinking water treatment plants in a southern city of China. The changes in N-nitrosamines are well correlated with dissolved organic matter (DOM), particularly fluorophores, which were measured and compared between traditional fluorescence indices and excitation-emission matrix coupled with parallel factor analysis (EEM-PARAFAC). Four of N-nitrosamine species including N-nitrosodimethylamine (NDMA), N-Nitrosodibutylamine (NDBA), N-Nitrosopyrrolidine (NPYR), and N-Nitrosodiphenylamine (NDPhA) are found to be abundant compounds with an average of 29.5% (26.7%), 20.0% (25.2%), 18.9% (16.0%), and 9.0% (9.9%) in the source (and treated) water, respectively. The sum of N-nitrosamines concentration is recorded to be low in the wet season (July-September), whereas the dry season (October-December) provided opposite impacts. EEM-PARAFAC modeling indicated the predominance of humic-like component (C1) in the wet season while in the dry season the water was dominant in protein-like component (C2). All the N-nitrosamines excluding NDPhA and N-Nitrosomorpholine (NMOR) showed a strong association with protein-like component (C2). In contrast, humic-like C1, which was directly influenced by rainfall, was found to be a suitable proxy for NMOR and NDPhA. The results of this study are valuable to understand the correlation between different N-nitrosamines and DOM through adopting fluorescence signatures.


Subject(s)
Drinking Water/analysis , Nitrosamines/analysis , Water Pollutants, Chemical/analysis , China , Chromatography, Liquid , Factor Analysis, Statistical , Humans , Humic Substances , Seasons , Spectrometry, Fluorescence , Tandem Mass Spectrometry
8.
ChemSusChem ; 13(1): 39-58, 2020 Jan 09.
Article in English | MEDLINE | ID: mdl-31696641

ABSTRACT

The selective electrochemical CO2 reduction (ECR) to CO in aqueous electrolytes has gained significant interest in recent years due to its capability to mitigate the environmental issues associated with CO2 emission and to convert renewable energy such as wind and solar power into chemical energy as well as its potential to realize the commercial use of CO2 . In view of the thermodynamic stability and kinetic inertness of CO2 molecules, the exploitation of active, selective, and stable catalysts for the ECR to CO is crucial to promote the reaction efficiency. Indeed, plenty of electrocatalysts for the selective ECR to CO have been explored, of which Ag is known as the most promising electrocatalyst for large-scale ECR to CO due to several competitive advantages including high catalytic performance, low price, and rich reserves compared with other metal counterparts. To provide useful guidelines for the further development of efficient catalysts for the ECR to CO, a comprehensive summary of the recent progress of Ag-based electrocatalysts is presented in this Review. Different modification strategies of Ag-based electrocatalysts are highlighted, including exposure of crystal facets, tuning of morphology and size, introduction of support materials, alloying with other metals, and surface modification with functional groups. The reaction mechanisms involved in these different modification strategies of Ag-based electrocatalysts are also discussed. Finally, the prospects for the development of next-generation Ag-based electrocatalysts are proposed in an effort to facilitate the industrialization of ECR to CO.

9.
Anal Chem ; 89(4): 2216-2220, 2017 02 21.
Article in English | MEDLINE | ID: mdl-28192948

ABSTRACT

Here, a g-C3N4 nanosheet modified microwell array providing enhanced electrochemiluminescence (ECL) and better visible sensitivity was prepared to simultaneously analyze total (membrane and intracellular) cholesterol at single cells. The detection limit for ECL visualization of hydrogen peroxide at microwell array was improved to be 500 nM that guaranteed the detection of low concentration cholesterol at single cells in parallel. To achieve single cell cholesterol analysis, the individual cells cultured at the microwell array were exposed to cholesterol oxidase generating hydrogen peroxide for luminescence analysis of membrane cholesterol, and then treated with triton X-100, cholesterol esterase, and cholesterol oxidase to produce hydrogen peroxide from intracellular cholesterol for luminescence determination. The observation of the luminescence spots at microwells in these two steps confirmed the codetection of membrane and intracellular cholesterol at single cells. The inhibition of intracellular acyl-coA/cholesterol acyltransferase (ACAT) resulted in less intracellular cholesterol storage (less luminescence) and more membrane cholesterol (more luminescence). The correlation of the luminescence intensity with the amount of cholesterol confirmed that our assay could simultaneously monitor membrane and intracellular cholesterol pools at different cellular states, which should offer more information for the study of cholesterol-related pathways at single cells.


Subject(s)
Cholesterol/analysis , Luminescent Measurements/methods , Nanostructures/chemistry , Nitriles/chemistry , Cell Membrane/metabolism , Cholesterol/metabolism , Cholesterol Oxidase/metabolism , Electrochemical Techniques , HeLa Cells , Humans , Hydrogen Peroxide/analysis , Limit of Detection , Microarray Analysis , Octoxynol/chemistry , Single-Cell Analysis , Sterol Esterase/metabolism , Sterol O-Acyltransferase/antagonists & inhibitors , Sterol O-Acyltransferase/metabolism
10.
Int Immunopharmacol ; 40: 106-114, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27588910

ABSTRACT

Transmembrane protein 16A (TMEM16A), a channel underlying the calcium-activated chloride channel (CaCC) currents, has been shown to be a key regulator of mucus overproduction in airway epithelial cells. However, the precise molecular mechanism involved in the TMEM16A-mediated mucus secretion remains unclear. In the present study, we inquired into a novel signaling mechanism for TMEM16A driving mucin 5AC (MUC5AC) production in human airway epithelial cells. Following treatment for 24-48h with type 13 interleukin (IL-13), an upregulation of TMEM16A expression in both mRNA and protein levels was observed in human bronchial epithelial cell line (HBE16), while signal transducer and activator of transcription 6 (STAT6) inhibition could decrease this elevated expression, suggesting that the regulation of TMEM16A expression by IL-13 was via a STAT6-based transcriptional mechanism. Further investigation of the HBE16 cells revealed that TMEM16A knockdown or specific chloride channel inhibitor T16Ainh-A01 could suppress the CaCC currents and consequently reduce the extracellular regulated kinase (ERK1/2) phosphorylation, accompanying a dramatical decrease in MUC5AC expression. Moreover, pretreated with PD98059, an inhibitor of ERK1/2, the HB16 cells showed a remarkable diminution in TMEM16A-mediated MUC5AC expression. Altogether, STAT6-TMEM16A-ERK1/2 signal pathway and TMEM16A channel activity are required for the IL-13-induced TMEM16A mediated mucus production.


Subject(s)
Chloride Channels/metabolism , Epithelial Cells/drug effects , Interleukin-13/pharmacology , MAP Kinase Signaling System/drug effects , Mucin 5AC/metabolism , Neoplasm Proteins/metabolism , STAT6 Transcription Factor/metabolism , Anoctamin-1 , Bronchi/cytology , Cell Line , Chloride Channels/genetics , Epithelial Cells/metabolism , Humans , Neoplasm Proteins/genetics , RNA, Small Interfering/genetics , STAT6 Transcription Factor/genetics
11.
PLoS One ; 11(4): e0153993, 2016.
Article in English | MEDLINE | ID: mdl-27092937

ABSTRACT

Rice is a model plant species for the study of cellulose biosynthesis. We isolated a mutant, S1-24, from ethyl methanesulfonate (EMS)-treated plants of the japonica rice cultivar, Nipponbare. The mutant exhibited brittle culms and other pleiotropic phenotypes such as dwarfism and partial sterility. The brittle culms resulted from reduced mechanical strength due to a defect in thickening of the sclerenchyma cell wall and reduced cellulose content in the culms of the S1-24 mutant. Map-based gene cloning and a complementation assay showed that phenotypes of the S1-24 mutant were caused by a recessive point mutation in the OsCESA7 gene, which encodes cellulose synthase A subunit 7. The missense mutation changed the highly conserved C40 to Y in the zinc finger domain. The OsCESA7 gene is expressed predominantly in the culm at the mature stage, particularly in mechanical tissues such as vascular bundles and sclerenchyma cells, consistent with the brittle phenotype in the culm. These results indicate that OsCESA7 plays an important role in cellulose biosynthesis and plant growth.


Subject(s)
Gene Expression Regulation, Plant/genetics , Glucosyltransferases/genetics , Mutation, Missense/genetics , Oryza/genetics , Plant Proteins/genetics , Zinc Fingers/genetics , Amino Acid Sequence , Carbohydrate Metabolism/genetics , Cell Wall/genetics , Cellulose/genetics , Chromosome Mapping/methods , Cloning, Molecular/methods , Molecular Sequence Data , Phenotype , Plant Development/genetics , Sequence Alignment
12.
Shanghai Kou Qiang Yi Xue ; 17(5): 552-4, 2008 Oct.
Article in Chinese | MEDLINE | ID: mdl-18989603

ABSTRACT

PURPOSE: To evaluate the quality of direct digital radiograph according to its application in dentistry. METHODS: 1195 patients with dental caries, periodontal diseases, periapical diseases, trauma of teeth or hypodontia were tested with Trophy elitys Radio Visio Graphy(RVG) and the quality of the tests was evaluated at four levels. RESULTS: It was convenient to operate RVG and easy to save the images, which reduced the amount of X-rays. 1587 pictures were taken, among which 92.3% was at level I, 6.3% was at level II,1.14% was at level III and level IV. CONCLUSIONS: The quality of the images at different positions is good, which can meet the requirement for clinical diagnosis. However, the radiography receptor should be improved for better images.


Subject(s)
Dental Caries/diagnostic imaging , Radiography, Dental, Digital , Humans , Radiographic Image Enhancement
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