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1.
Ecotoxicol Environ Saf ; 268: 115732, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38000301

RESUMEN

Glutathione plays a critical role in plant growth, development and response to stress. It is a major cellular antioxidant and is involved in the detoxification of xenobiotics in many organisms, including plants. However, the role of glutathione-dependent redox homeostasis and associated molecular mechanisms regulating the antioxidant system and pesticide metabolism remains unclear. In this study, endogenous glutathione levels were manipulated by pharmacological treatments with glutathione synthesis inhibitors and oxidized glutathione. The application of oxidized glutathione enriched the cellular oxidation state, reduced the activity and transcript levels of antioxidant enzymes, upregulated the expression level of nitric oxide and Ca2+ related genes and the content, and increased the residue of chlorothalonil in tomato leaves. Further experiments confirmed that glutathione-induced redox homeostasis is critical for the reduction of pesticide residues. RNA sequencing analysis revealed that miRNA156 and miRNA169 that target transcription factor SQUAMOSA-Promoter Binding Proteins (SBP) and NUCLEAR FACTOR Y (NFY) potentially participate in glutathione-mediated pesticide degradation in tomato plants. Our study provides important clues for further dissection of pesticide degradation mechanisms via miRNAs in plants.


Asunto(s)
Plaguicidas , Solanum lycopersicum , Antioxidantes/metabolismo , Solanum lycopersicum/genética , Disulfuro de Glutatión/metabolismo , Glutatión/metabolismo , Oxidación-Reducción , Plaguicidas/metabolismo , Plantas/metabolismo , Homeostasis , Estrés Oxidativo
2.
Huan Jing Ke Xue ; 44(2): 646-657, 2023 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-36775589

RESUMEN

In order to explore the composition and source characteristics of non-polar organic compounds (NPOCs) in atmospheric fine particulate matter in the Yangtze River Delta region, 129 PM2.5 samples were collected at the Regional Atmospheric background station in Lin'an from December 2019 to November 2020. Including polycyclic aromatic hydrocarbons (PAHs), n-alkanes, and hopanes, the main sources of organic aerosols were investigated using molecular tracers, eigen ratios, and orthogonal matrix factorization models. The results showed that the average annual mass concentration of PM2.5 in Lin'an was approximately (32.36±20.44) µg·m-3, and the average annual mass concentration of NPOCs was approximately (59.05±40.39) ng·m-3, showing the seasonal characteristics of being high in winter and low in summer. n-alkanes mainly came from fossil fuels and biomass (grass, wood, etc.) burning, followed by cuticle wax emission from higher plants. PAHs mainly came from the mixed contribution of non-fossil sources such as coal burning motor vehicle emissions and biomass combustion. Hopanes were mainly derived from motor vehicle emissions, which were also affected by coal burning in winter. Backward trajectory cluster analysis and potential source analysis showed that Lin'an was mainly affected by external air mass transport. Combined with the orthogonal matrix-factor decomposition model, NPOCs observed during the sampling period were analyzed, and non-fossil sources such as coal burning sources, transportation emission sources, and biomass combustion were obtained. In winter, transportation sources were the main source, accounting for 59%. In spring and summer, coal burning was the main source, accounting for 58% and 57%, respectively. In autumn, biomass combustion and other non-fossil sources dominated, accounting for 64%.

3.
Huan Jing Ke Xue ; 43(6): 2858-2866, 2022 Jun 08.
Artículo en Chino | MEDLINE | ID: mdl-35686755

RESUMEN

Carbonaceous aerosol is an important component of atmospheric fine particles that has an important impact on air quality, human health, and climate change. In order to explore the long-term changes in carbonaceous aerosol under the background of emission reduction, this study measured the mass concentrations of organic carbon (OC) and elemental carbon (EC) of PM2.5, which collected in the northern suburbs of Nanjing for five years (December 17, 2014 to January 5, 2020). The results showed that the five-year average ρ(OC) and ρ(EC) were (10.2±5.3) µg·m-3 and (1.6±1.1) µg·m-3, accounting for 31.1% and 5.2% of PM2.5, respectively. OC and EC concentrations were both high in winter and low in summer. According to the nonparametric Mann-Kendall test and Sen's slope, the mass concentrations of OC and PM2.5 decreased significantly[OC:P<0.0001, -0.79 µg·(m3·a)-1, -0.29%·a-1; PM2.5:P<0.0001, -4.59 µg·(m3·a)-1, -1.58%·a-1]. Although EC had an upward trend, the significance and range of change were not obvious[P=0.02, 0.05 µg·(m3·a)-1, 0.02%·a-1]. OC and EC decreased significantly during winter from 2014 to 2019[OC:P<0.0001, -2.05 µg·(m3·a)-1, -0.74%·a-1; EC:P=0.001, -0.15 µg·(m3·a)-1, -0.05%·a-1], and the decline was more obvious than the whole. The correlation between OC and EC showed that the sources in winter and summer were more complex than those in spring and autumn. According to the characteristic ratio of OC and EC, the contribution of coal combustion and biomass burning decreased from 2015 to 2019, whereas the impact of industrial sources and vehicle emissions became more significant. Corresponding to this was the obvious decline in OC and the slight recovery of EC. The OC/EC ratio was over 2.0, indicating that there was secondary pollution in the study area. Further calculation revealed that the variation in SOC was consistent with that in OC, showing a significant decrease[P<0.0001, -0.47 µg·(m3·a)-1, -0.17%·a-1]. The average mass concentration of SOC was (5.0±3.5) µg·m-3, accounting for 49.2% of OC. These changes indicate clear effects of the prevention and control of air pollution in Nanjing in recent years. Furthermore, future control can focus on the emissions of VOCs to reduce secondary pollution.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Carbono/análisis , Monitoreo del Ambiente , Humanos , Material Particulado/análisis
4.
Huan Jing Ke Xue ; 43(6): 2895-2905, 2022 Jun 08.
Artículo en Chino | MEDLINE | ID: mdl-35686759

RESUMEN

The non-polar compounds in atmospheric fine particles (PM2.5) mainly include polycyclic aromatic hydrocarbons (PAHs) and normal alkanes (n-alkanes), etc., which are usually used to identify the source of the air pollution and have a great important impact on human health and the environment. To study the pollution characteristics and sources of non-polar organic aerosols in the background point PM2.5 in Guangxi, from November 2017 to October 2018, 17 types of PAHs and 20 types of n-alkanes were analyzed on PM2.5 samples collected in the field. It was found that the annual average concentrations of PAHs and n-alkanes were 4.28±4.25 ng·m-3 and 13.7±14.72 ng·m-3, respectively. The seasonal change was as follows:winter[(7.86±5.19) ng·m-3, (27.51±16.90) ng·m-3]>spring[(2.73±1.76) ng·m-3, (7.64±4.71) ng·m-3]>autumn[(2.34±145) ng·m-3, (7.01±4.55) ng·m-3]>summer[(1.91±1.67) ng·m-3, (3.98±3.12) ng·m-3]. In PAHs, 5-ring and 6-ring molecules accounted for more than 60%, followed by low- and medium-ring molecules (4-ring and 3-ring). The high molecular weight of n-alkanes was relatively high (C29>C31>C27), and the odd and even carbon numbers were significantly different. In addition, combined with the feature ratio method, principal component analysis method, and backward trajectory joint verification, it was found that 41.5% of non-organic aerosols in winter were affected by maritime traffic emissions and ocean source transportation, and 36.7% of the pollution was explained by the coal burning and local biomass burning; 25.2% of the pollution in spring came from biomass combustion and transportation, and 45.0% was attributed to marine transportation in the southern part of the study area and higher plant wax emissions pollution; 53.4% of pollution in summer came from polluted ship emissions, and 10.6% of pollution came from transportation in Southwest Thailand Source transportation. The organic aerosols at the background sites in Guangxi were affected by the combined effects of local emissions and transmission sources.


Asunto(s)
Contaminantes Atmosféricos , Hidrocarburos Policíclicos Aromáticos , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Alcanos/análisis , China , Monitoreo del Ambiente , Humanos , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis
5.
Ecotoxicol Environ Saf ; 233: 113296, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35158253

RESUMEN

Glutathione (GSH) biosynthesis and regeneration play a significant role in the metabolism of chlorothalonil (CHT) in tomatoes. However, the specific regulatory mechanism of GSH in the degradation of CHT remains uncertain. To address this, we investigate the critical regulatory pathways in the degradation of residual CHT in tomatoes. The results revealed that the detoxification of CHT residue in tomatoes was inhibited by buthionine sulfoximine and oxidized glutathione pretreatment, which increased by 26% and 46.12% compared with control, respectively. Gene silencing of γECS, GS, and GR also compromised the CHT detoxification potential of plants, which could be alleviated by GSH application and decreased the CHT accumulation by 33%, 25%, and 21%, respectively. Notably, it was found that the jasmonic acid (JA) pathway participated in the degradation of CHT regulated by GSH. CHT residues reduced by 28% after application of JA. JA played a role downstream of the glutathione pathway by promoting the degradation of CHT residue in tomatoes via nitric oxide signaling and improving the gene expression of antioxidant and detoxification-related enzymes. This study unveiled a crucial regulatory mechanism of GSH via the JA pathway in CHT degradation in tomatoes and offered new insights for understanding residual pesticide degradation.


Asunto(s)
Solanum lycopersicum , Ciclopentanos , Glutatión/metabolismo , Solanum lycopersicum/genética , Nitrilos , Oxilipinas/metabolismo
6.
Opt Express ; 29(23): 37464-37475, 2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34808817

RESUMEN

A four-mode 2D/3D switchable display using a 1D/2D convertible liquid crystal (LC) lens array is proposed in this paper. The LC lens array is composed of two orthogonal LC lens arrays, with a λ/2 film in the middle to rotate the polarization by 90°. Based on the LC lens array, a four-mode 2D/3D switchable display is realized, which is switchable between the turn-off and turn-on states: when the operating voltage V1 = 0, V2 = 0, the display operates in mode I, which is 2D display; when the operating voltage V1 = 0, V2 = 0, the display operates in mode II, and the 3D display effect is in x direction; when the operating voltage V1 = 0, V2 = 0, the display operates in mode III, and the 3D display effect is in y direction; when the operating voltage V1 = 0, V2 = 0, the display operates in mode IV, the 3D display effect is in x-y plane. Experimental results indicate that the LC lens array has simple fabrication process, low operating voltage (∼5.4V), and short focal length. Moreover, based on the designed LC lens array, the 2D/3D switchable display shows no moiré pattern.

7.
Diabetes Ther ; 11(3): 701-710, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32020552

RESUMEN

INTRODUCTION: The aim of this study was to compare the efficacy of vildagliptin as add-on therapy to short-term continuous subcutaneous insulin infusion (CSII) with CSII monotherapy in hospitalized patients with type 2 diabetes mellitus (T2DM). METHODS: A total of 200 hospitalized patients with inadequately controlled T2DM were randomized into groups, with one group receiving CSII monotherapy (CSII group, n =100) and the other group receiving CSII plus vildagliptin as add-on (CSII + Vig group, n = 100). Of these, 191 completed the 7-day trial (CSII group, n = 99; CSII + Vig group, n = 92) and included in the analysis. The glycemic control and variability of the patients were measured using all-day capillary blood glucose (BG) monitoring. Weight and fasting C-peptide levels were evaluated before and after the interventions. RESULTS: Mean BG concentrations during the whole treatment period were lower and the time to reach target BG was reduced in the CSII + Vig group compared with the CSII group (9.89 ± 3.37 vs. 9.46 ± 3.23 mmol/L, P < 0.01; 129 ± 4 vs. 94 ± 5 h, P < 0.01, respectively). Similarly, the indicators of glycemic variability, namely the standard deviation of BG and the largest amplitude of glycemic excursion, were significantly decreased in the CSII + Vig group compared with the CSII group (2.68 ± 1.05 vs. 2.39 ± 1.00 mmol/L, P < 0.01; 7.19 ± 2.86 vs. 6.23 ± 2.73 mmol/L, P < 0.01, respectively). CONCLUSIONS: Short-term CSII with vildagliptin as add-on therapy may be an optimized treatment for hospitalized patients with T2DM compared with short-term CSII monotherapy.

8.
Nan Fang Yi Ke Da Xue Xue Bao ; 36(11): 1546-1549, 2016 Nov 20.
Artículo en Chino | MEDLINE | ID: mdl-27881348

RESUMEN

OBJECTIVE: To analyze the clinical factors that contribute to lowered bone mineral density (BMD) of the lumbar vertebrae in type 2 diabetic patients. METHODS: Forty type 2 diabetic patients with osteoporosis and 40 age- and gender-matched healthy individuals, selected using propensity score method, were examined for BMD of the L1 to L4 vertebrae and the left femur. Age, gender, course of the disease, body mass index (BMI), fasting blood glucose, serum calcium, serum phosphate, urinary calcium, and urinary phosphate were compared between the two groups. RESULTS: BMD of the L1 to L4 vertebras was significantly lower in the diabetic group than in the healthy individuals (P<0.05). In the diabetic patients, BMD showed an obvious difference between male and female patients and was negatively correlated with the course of the disease but positively with BMI, fasting blood glucose, urinary calcium and urinary phosphate; BMD was not correlated with age, serum calcium or serum phosphate in these patients. CONCLUSION: Osteoporosis in type 2 diabetic patients is closely related with gender, BMI, course of the disease and poorly controlled glucose level.


Asunto(s)
Densidad Ósea , Diabetes Mellitus Tipo 2/complicaciones , Osteoporosis/complicaciones , Absorciometría de Fotón , Glucemia/análisis , Índice de Masa Corporal , Calcio/sangre , Calcio/orina , Estudios de Casos y Controles , Femenino , Humanos , Vértebras Lumbares/patología , Masculino , Fosfatos/sangre , Fosfatos/orina
9.
Comput Intell Neurosci ; 2016: 9891382, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27057159

RESUMEN

For improving convergence rate and preventing prematurity in quantum evolutionary algorithm, an allele real-coded quantum evolutionary algorithm based on hybrid updating strategy is presented. The real variables are coded with probability superposition of allele. A hybrid updating strategy balancing the global search and local search is presented in which the superior allele is defined. On the basis of superior allele and inferior allele, a guided evolutionary process as well as updating allele with variable scale contraction is adopted. And H ε gate is introduced to prevent prematurity. Furthermore, the global convergence of proposed algorithm is proved by Markov chain. Finally, the proposed algorithm is compared with genetic algorithm, quantum evolutionary algorithm, and double chains quantum genetic algorithm in solving continuous optimization problem, and the experimental results verify the advantages on convergence rate and search accuracy.


Asunto(s)
Algoritmos , Inteligencia Artificial , Simulación por Computador , Teoría Cuántica
10.
Mol Med Rep ; 13(6): 5077-83, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27109489

RESUMEN

Synucleinopathies and abnormalities in the nerves of the enteric nervous system are hypothesized to be involved in age-associated motility disorders. The aim of the present study was to investigate the expression of various antigens, including α­synuclein (Syn) and its post­translational modified forms, in the human colon at various ages. In addition, the study aimed to correlate the expression of Syn with neurodegeneration. Immunohistochemistry was used to detect the expression of neurofilament (NF), Syn, as well as its nitrated (N) form in the healthy colonic tissue of 12 young (34.08±5.12 years), 10 middle­aged (51.80±3.52 years), and 11 elderly (75.82±7.70 years) individuals. To the best of our knowledge, the current study is the first to demonstrate the presence of N­Syn in the colonic tissue. N­Syn was identified in the upper layer of the mucosa and submucosa layer. Furthermore, Syn (wild­type) was present in the mucosa and submucosa. The number of NF­positive neurons in the submucosal layer declined significantly with age (P<0.01). In addition, Syn and N­Syn significantly increased during aging (P<0.01). Furthermore, a negative correlation was identified between neuron number and synucleinopathies, indicating the abnormal accumulation of both wild-type Syn and N­Syn in the mucosa, submucosa, muscle layer and myenteric plexus. The present study demonstrates that the Syn pathology may be linked to colic neuronal degeneration during normal aging, and this link may cause functional deficits.


Asunto(s)
Colon/inervación , Colon/metabolismo , Degeneración Nerviosa/metabolismo , Procesamiento Proteico-Postraduccional , alfa-Sinucleína/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Plexo Mientérico/metabolismo , Plexo Mientérico/patología , Neuronas/metabolismo , Neuronas/patología , Plexo Submucoso/metabolismo , Plexo Submucoso/patología
11.
Oncol Lett ; 3(2): 391-394, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22740918

RESUMEN

Langerhans cell histiocytosis (LCH) is a rare disease of unknown etiology characterized by oligoclonal proliferation of Langerhans cells. The diagnosis of LCH is complicated by the fact that it may involve multiple organ systems and its clinical presentation and course varies, ranging from an isolated to a multisystem disease. We report a 35-year-old male with LCH involving multiple systems, including the bones, lungs, spleen, liver and bile ducts, whose first clinical presentation was liver dysfunction. The patient was diagnosed following a skull biopsy that revealed infiltration of Langerhans cells. However, a liver biopsy revealed sclerosing cholangitis (SC) with no signs of Langerhans cell infiltration, and the clinical manifestations of the involved organs were atypical, leading to a delayed diagnosis. The patient was in partial remission following chemotherapy. In conclusion, findings of this case may aid our understanding of the pathophysiology of LCH and in improving its diagnosis and treatment.

12.
Zhonghua Er Ke Za Zhi ; 47(8): 628-31, 2009 Aug.
Artículo en Chino | MEDLINE | ID: mdl-19951500

RESUMEN

OBJECTIVE: To investigate the changes of neutrophils in airway inflammation in children with severe asthma. METHOD: Children with mild to moderate asthma (n=23), severe asthma (n=16) and healthy control subjects (n=16) underwent lung function tests and sputum induction. The sputum specimens were assayed for cellular differential count, the supernatant and peripheral blood were assayed for the concentrations of IL-8 by "sandwich" enzyme linked immunosorbent assay (ELISA). Sputum supernatant, IL-8 and mifepristone were assessed for their abilities to prolong the in vitro survival of blood-derived neutrophils. RESULT: The percentage of sputum neutrophils was significantly higher in severe asthmatics [59.54 (41.99-74.65)%] than mild-moderate asthmatics [30.03 (15.94-47.71)%] and healthy control subjects [29.72(16.53-45.74)%] (P < 0. 01); the level of IL-8 in sputum was significantly higher in severe asthmatics [2907.78 (331.67 - 3457.93) ng/L] than mild-moderate asthmatics [287.58 (130.75-656.84) ng/L] and healthy control subjects [179.2 (58.55-346.59) ng/L] (P < 0.01); the percentages of neutrophilic apoptosis respectively cultured with LPS [(10.57 +/- 1.97)%], severe asthmatics supernatant [(11.82 +/- 2.96)%], IL-8 [(10.47 +/- 1.93)%], dexamethasone [(9.93 +/- 1.95)%], severe asthma supernatant + mifepristone [(12.15 +/- 2.86)%] in vitro were lower than that cultured with PBS [(17.98 +/- 2.27)%], healthy control supernatant [(17.37 +/- 2.50)%], mild-moderate asthmatics supernatant [(16.35 +/- 3.26)%], mifepristone [(17.89 +/- 2.38)%], and dexamethasone + mifepristone [(17.06 +/- 2.59)%] (P < 0.01). CONCLUSION: Suppression of neutrophilic apoptosis seems to play a potential role in airway neutrophilic inflammation in severe asthmatics, and the level of IL-8 in sputum was significantly higher in patients with severe asthmatics.


Asunto(s)
Apoptosis , Asma/metabolismo , Asma/patología , Neutrófilos/citología , Adolescente , Asma/fisiopatología , Estudios de Casos y Controles , Niño , Femenino , Humanos , Inflamación , Interleucina-8/metabolismo , Recuento de Leucocitos , Masculino , Sistema Respiratorio/metabolismo , Sistema Respiratorio/patología , Esputo/metabolismo
13.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 24(2): 186-8, 2007 Apr.
Artículo en Chino | MEDLINE | ID: mdl-17407078

RESUMEN

OBJECTIVE: To investigate the polymorphism of Kell blood group system in Chinese and to find a suitable method for large scale screening. METHODS: An analysis method of polymerase chain reaction-restriction fragment-single strand conformation polymorphism (PCR-RF-SSCP) combined with heteroduplex was established to detect abnormal sample in KEL exon 7-9 area, then sequencing was used to find out the mutation site. RESULTS: Two mutations were found from 500 samples: 966G > A mutation in exon 9 and C > A mutation in 67th site of intron 7, both with no amino acid change. The mutation rate was 4/1000. No mutation was found as missed in using PCR-RF-SSCP combined with heteroduplex. CONCLUSION: PCR-RF-SSCP combined with heteroduplex is confirmed as an effective, economical and simple method, it is quite suitable for large scale population screening study with unclear gene background and unavailable positive controls. Since there is special polymorphism for Kell blood group system in Chinese, further study is needed.


Asunto(s)
Análisis Heterodúplex/métodos , Sistema del Grupo Sanguíneo de Kell/genética , Reacción en Cadena de la Polimerasa/métodos , Pueblo Asiatico/genética , China , Humanos , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo Conformacional Retorcido-Simple
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