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1.
Huan Jing Ke Xue ; 44(12): 6586-6597, 2023 Dec 08.
Article in Chinese | MEDLINE | ID: mdl-38098386

ABSTRACT

Temperature is a key meteorological factor affecting ozone formation. In general, a positive correlation is observed between ozone and temperature, that is, ozone concentration increases with the increase in temperature. However, this relationship may change at extremely high temperatures. When the temperature exceeds a threshold value, the ozone concentration tends to decrease, which is referred to as an ozone suppression event. Ozone suppression events lead to greater uncertainties in the prediction of future air quality under climate change. Based on the national air quality monitoring data, reanalysis data, and meteorological observation data, this study used the Z test to systematically analyze the spatio-temporal characteristics of the critical temperature(Tx) and frequency of ozone suppression events in China during the warm season(April to September) from 2013 to 2020 and further analyzed the possible influencing factors for the occurrence of ozone suppression events. The results showed that approximately 18% of the sites in China experienced ozone suppression events in the warm season from 2013 to 2020. The sites with a high frequency of ozone suppression events were mainly distributed in the central and western regions of China, such as Sichuan, Xinjiang, and Shaanxi, with an average frequency of ten times per year. The critical temperature(Tx) ranged from 19.2 to 39.3℃, and the Tx of most sites showed an increasing trend from 2013 to 2020. The high values of Tx were mainly distributed in the central and western regions such as Sichuan, Chongqing, Hunan, and Hubei, whereas the low values of Tx were concentrated in the Qinghai-Tibet Plateau. Contrary to the interannual trend of Tx, the frequency of ozone suppression events decreased significantly in the Beijing-Tianjin-Hebei Region and exhibited a characteristic of "increase-decrease-increase" in the Fenwei Plain, the Yangtze River Delta, and the Chengdu-Chongqing regions. The most significant effect of extreme high temperature on ozone suppresion was found in the Pearl River Delta Region. In addition, ozone precursors(e.g., NO2) and meteorological conditions(wind speed and direction) were possible factors affecting the occurrence of ozone suppression events.

2.
Huan Jing Ke Xue ; 43(1): 160-169, 2022 Jan 08.
Article in Chinese | MEDLINE | ID: mdl-34989500

ABSTRACT

With the rapid development of urbanization, ozone (O3) pollution is an ongoing occurrence in the Pearl River Delta (PRD) region in China. The effective control of O3 pollution is a great challenge owing to the nonlinear relationship between O3 and precursor emissions and the effect of meteorological conditions. Based on the regional air quality model CAMx-OSAT (ozone source apportionment technology), O3 formation regimes were determined, and inter-city transportation across PRD was quantified under different transmission channels. The results showed that spatial differences were observed for the O3 formation regimes under different transmission channels. The VOCs-sensitive regime was mainly located in the central areas of the PRD region, and the NOx-sensitive regime was distributed in the suburban areas of the PRD regions under calm wind conditions. When the northeast wind was prevailing, the polluted air mass of the urban agglomeration was transmitted southwesterly downward, resulting in the downwind areas being transformed to VOCs-sensitive; the upwind areas were still NOx-sensitive. Under the southeast wind, the VOCs-sensitive regime had a banding distribution along the southeast-northwest direction, and the remaining areas were NOx-sensitive. With the influence of transmission channels, downwind cities were significantly affected by the transmission of upwind urban agglomerations (41%-87%), whereas the local formation was the main contributor under the calm wind conditions (60%-87%). To explore the relationship between O3 and precursor emissions, a series of sensitivity tests were designed. The results showed that maximized areas (20%-36%) with reductions in O3 can be achieved by reducing VOCs and NOx in the corresponding sensitive regimes, and the maximized level with the reduction in O3 can be fulfilled by reducing VOCs in the VOCs-sensitive regime. For the typical city Jiangmen, the area that met the standard increased the most under the calm wind (11%) and southeast wind (8%) conditions when VOCs and NOx were reduced in the corresponding sensitive regimes. Additionally, under northeast wind conditions, reducing VOCs in the VOCs-sensitive regime can more effectively control O3, as the area up to the standard increased by 140%.


Subject(s)
Air Pollutants , Air Pollution , Ozone , Volatile Organic Compounds , Air Pollutants/analysis , China , Environmental Monitoring , Ozone/analysis , Rivers , Volatile Organic Compounds/analysis
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 40(3): 499-503, 2009 May.
Article in Chinese | MEDLINE | ID: mdl-19627014

ABSTRACT

OBJECTIVE: To establish a diagnostic model for systemic lupus erythematosus (SLE) using proteiomic fingerprint techology. METHODS: Blood samples were collected from 64 cases of SLE, 30 cases of rheumatoid arthritis (RA), 30 cases of Sjogren's syndrome (SS), 25 cases of systemic sclerosis (SSc), as well as 83 healthy controls. Proteomic spectra of these 232 serum samples were generated by proteomic fingerprint technology. Diagnostic model was established by a machine learning algorithm called decision boosting. The sensitivity and specificity of the diagnostic model was validated with a blinded testing set. RESULTS: Sixty differential protein peaks (P<0.05) between SLE and control subjects were indicated, 28 of them were up regulated and 32 were down regulated in SLE patients. The algorithm identified a cluster pattern segregating SLE from non-SLE with sensitivity of 91% and specificity of 92%. The discriminatory diagnostic pattern correctly identified SLE. A sensitivity of 78% and specificity of 96% for the blinded test were obtained when comparing SLE vs non-SLE. CONCLUSION: This diagnostic model using proteiomic fingerprint techology appears to be a promising tools with high sensitivity and specificity in diagnosis of SLE.


Subject(s)
Blood Proteins/analysis , Lupus Erythematosus, Systemic/diagnosis , Proteomics/methods , Biomarkers/analysis , Blood Proteins/genetics , Female , Humans , Lupus Erythematosus, Systemic/blood , Male , Models, Biological , Sensitivity and Specificity
4.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 40(3): 504-7, 512, 2009 May.
Article in Chinese | MEDLINE | ID: mdl-19627015

ABSTRACT

OBJECTIVE: To investigate the proteomic characteristics of systemic lupus erythematosus (SLE) in a SLE family from Sichuan, China which consisting of 7 members with 3 SLE cases, and to find the proteins correlated with the heredity of SLE. METHODS: A total of 153 serum samples were collected from 7 members including 3 SLE sisters in this SLE family, 63 individual SLE patients, as well as 83 healthy controls. The diagnosis of SLE is based on the American College of Rheumatology criteria (1997). All serum samples were analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) combined with magnetic beads technology. Serum protein profiles were obtained by MALDI-TOF-MS combined with magnetic beads in order to identify predictive biomarkers of risk of suffering SLE. The resulting spectra were analyzed with Biomarker Wizard software 3.1.0. RESULTS: Four discriminative mass/charge (m/z) proteins serving as pathogenic biomarkers were identified on arrays for family SLE cases versus individual SLE and healthy controls. The protein level of peak intensities at m/z of 9342.23 was significantly greater in SLE family group compared with that in individual SLE patients and healthy controls (P<0.05), those of individual SLE patients were significantly greater compared with healthy controls (P<0.05); the proteins level of peak intensities at m/z of 4094.03, 5905.35 and 7973.53 in SLE family group were significantly lower compared with that in individual SLE patients and healthy controls (P<0.05), those of individual SLE patients were significantly lower compared with healthy controls (P<0.05). CONCLUSION: The proteins of m/z of 9342.23, 4094.03, 5905.35 and 7973.53 maybe play a great role in assemble pathogenesis of SLE and predict the risk of suffering SLE. The higher protein level of m/z of 9342.23 and the lower protein level of m/z of 4094.03, 5905.35 and 7973.53, the higher risk of sufferring with SLE.


Subject(s)
Blood Proteins/analysis , Lupus Erythematosus, Systemic/genetics , Proteomics/methods , Adolescent , Adult , Aged , Biomarkers/analysis , Blood Proteins/genetics , China , Female , Humans , Lupus Erythematosus, Systemic/blood , Male , Middle Aged , Pedigree , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Young Adult
5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 40(2): 190-4, 2009 Mar.
Article in Chinese | MEDLINE | ID: mdl-19462887

ABSTRACT

OBJECTIVE: To evaluate the anticancer effect of liposome plus Ad-Endostatin complex on human ovarian serous cystocarcinoma. METHODS: The recombinant endostatin was expressed in the SKOV3 cells transfected with constructed adenovirus. The nude mice models with human ovarian serous cystocarcinoma were divided into six groups randomly: (1) Ad-hEndo-H plus liposome group (abbreviation: lipo+Ad-hEndo-H), i.v. administration of 1 x 10(9) pfu (plaque-forming units) recombinant adenovirus plus 200 microg liposome (n=5); (2) Ad-hEndo-L plus liposome group (abbreviation: lipo+Ad-hEndo-L), i.v. administration of 1 x 10(8) pfu recombinant adenovirus plus 20 microg liposome (n=5); (3) Ad-hEndo group, i.v. administration of 1 x 10(9) pfu recombinant adenovirus (n=4) (4) Ad-null plus liposome group, i.v. administration of 1 x 10(9) pfu adenovirus plus 200 microg liposome (n=4); (5) liposome group, i.v. administration of liposome 200 microg (n=4) (6) NS group, i.v. administration of equal volume of normal saline as above (n=4). The tumor size was monitored every 7 days. All of the nude mice were sacrificed 49 days after the tumor establishment. The tumors were removed and weighted. The micro-vessel density (MVD) was counted and the apoptotic cells were measured in the tumors tissue by TUNEL. The effect of the antibody of adenovirus was investigated with the SKOV3 cells transfected with liposome-complexed adenovirus. RESULTS: The tumors of the mice in the lipo+Ad-hEndo-H and lipo+Ad-hEndo-L groups weighted 54.74% and 70.65% lighter than the NS controls, respectively (P < 0.05). The tumors in the lipo+Ad-hEndo-L and lipo+Ad-hEndo-H groups had fewer MVD and more apoptotic cells than those in the other groups (P < 0.05). The antibody of adenovirus had less impact on the adenovirus capability of transfect when it was combined with liposome than without liposome. CONCLUSIONS: The liposome plus Ad-Endostatin complex inhibits the growth of human ovarian serous cystocarcinoma effectively. Lower dose of repeated injection of adenovirus with liposome is preferable.


Subject(s)
Adenoviridae/genetics , Endostatins/genetics , Genetic Therapy/methods , Liposomes/therapeutic use , Ovarian Neoplasms/therapy , Animals , Apoptosis/drug effects , Cations , Cell Proliferation/drug effects , Cystadenocarcinoma, Serous/therapy , Drug Delivery Systems , Endostatins/metabolism , Endostatins/therapeutic use , Female , Genetic Vectors/therapeutic use , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasm Transplantation , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Recombinant Proteins/therapeutic use
6.
World J Gastroenterol ; 14(4): 622-6, 2008 Jan 28.
Article in English | MEDLINE | ID: mdl-18203298

ABSTRACT

AIM: To test the clinical significance of antineutrophil cytoplasmic antibody (ANCA) in evaluation of adult Henoch-Schonlein purpura (HSP) patients presenting mainly with abdominal symptoms. METHODS: Twenty-eight consecutive HSP patients who presented predominantly with abdominal symptoms were enrolled in this study. Control subjects included 27 age- and sex-matched patients with peptic ulcer disease, colon cancer, acute gastroenteritis, irritable bowel syndrome and colonic polyps. ANCA was measured by indirect immunofluorescence (IIF) in all patients, and follow-up ELISA was performed in patients with positive IIF tests. RESULTS: ANCA was detected in 9 HSP patients by IIF (2 were positive for c-ANCA and 7 were positive for p-ANCA). No ANCA was found in the control group. The sensitivity and specificity of a positive ANCA test (either c- or p-ANCA) were 32.1% and 100% respectively. Only one out of the 9 patients with positive ANCA by IIF had positive ANCA by ELISA and the antigen was myeloperoxidase (MPO). The patients positive for ANCA had higher HSP clinical scores, and were more likely to have renal function impairment. Patients with late purpura development were also associated with more severe clinical manifestations. CONCLUSION: A positive ANCA test is associated with more severe symptoms in HSP. After inflammatory bowel disease is excluded, a positive ANCA test provides a clue to the diagnosis of HSP presenting predominantly with abdominal symptoms.


Subject(s)
Antibodies, Antineutrophil Cytoplasmic/blood , Gastrointestinal Diseases/diagnosis , Gastrointestinal Diseases/immunology , IgA Vasculitis/diagnosis , IgA Vasculitis/immunology , Adult , Biomarkers/blood , Female , Gastrointestinal Diseases/etiology , Humans , IgA Vasculitis/complications , Male , Predictive Value of Tests , Sensitivity and Specificity , Severity of Illness Index
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