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1.
Huan Jing Ke Xue ; 43(10): 4522-4535, 2022 Oct 08.
Article in Chinese | MEDLINE | ID: mdl-36224138

ABSTRACT

Natural colloids (NCs) are ubiquitous in sediments and soils, which could affect the environmental fate of antibiotics. Focusing on chloramphenicol (CAP), different sources of the sediments and soil samples were selected to research the sorption capacity of NCs with different relative molecular weights towards CAP, as well as the impactors, combined with a multi-method approach including cross-flow ultrafiltration, dynamic light scattering, UV-visible absorption spectroscopy, and three-dimensional excitation-emission matrix fluorescence spectroscopy. The results revealed that the low molecular weight (LMW) of NCs was associated with a low autochthonous origin and a higher humification degree. The high molecular weight (HMW) of NCs were mainly terrestrial sources, and the aromatic rings contained more oxygen-containing functional groups such as carboxyl, hydroxyl, and carbonyl groups. Four fluorescence components were identified using the parallel factor analysis model, and the humic-like substances were the primary fluorescent components. Moreover, based on batch experiments, the study investigated the sorption behavior of CAP by the different fractions of the solid samples. The results showed that the sorption processes of CAP were well fitted by the linear model and Freundlich model. The average sorption rate of CAP by the original solid samples and the solid samples with removed organic and inorganic carbon were 4.46%, 3.93%, and 6.61%, respectively, indicating that organic carbon played an important role in the sorption behavior of CAP. The results of the sorption experiments indicated that CAP was more easily adsorbed on the LMW NCs that had a high degree of humification and a more aliphatic chain on the aromatic rings. In addition, tryptophan-like protein substances in NCs showed the inhibiting effect on the sorption progress of CAP. Redundancy analysis indicated that the sorption of CAP by NCs in sediment and soil was mainly related to the source, aromatics, oxygen functional groups on aromatic rings, humification degree, and humic-like substances of NCs.


Subject(s)
Soil Pollutants , Soil , Adsorption , Anti-Bacterial Agents , Carbon/chemistry , Chloramphenicol , Colloids , Geologic Sediments/chemistry , Humic Substances/analysis , Oxygen/analysis , Soil Pollutants/analysis , Tryptophan
2.
Huan Jing Ke Xue ; 43(2): 847-858, 2022 Feb 08.
Article in Chinese | MEDLINE | ID: mdl-35075858

ABSTRACT

At present, there are few studies on the spectral characteristics of dissolved organic matter (DOM) in the sediments of the Poyang Lake basin. Therefore, excitation-emission matrix spectroscopy (EEMs) technology and ultraviolet-visible spectra combined with the parallel factor analysis (PARAFAC) were applied to investigate the fluorescent components and sources of DOM in sediments from Poyang Lake. The results showed that the DOM in sediments originated from both terrestrial and autochthonous sources with a high humification. Compared with the sub-lakes, the DOM from the main lake was characterized with a higher concentration of colored DOM, larger particle size, and higher aromaticity and humification degree. In addition, four fluorescence components of DOM in sediments were identified by the PARAFAC model, including three humic-like components (C1, C2, and C4) and one protein-like component (C3). The fluorescence intensity of the humic substances in the sub-lakes was higher than those in the main lake. Furthermore, the percentage of fluorescence abundance of C1 was the highest both in the sub-lakes (42%) and main lake (46%). The spatial distribution of the fluorescence intensity of the four components gradually increased from west to east, and the peak values were observed in the Duchang and Nanji Wetland. This may be related to the death of a large number of plants due to the rise in the water level during the wet season and human activities. Principal component analysis showed that although there were no significant differences in the four fluorescent components between the sub-lakes and the main lake, the humification degree of DOM in the sub-lakes was slightly higher than that in the main lake.


Subject(s)
Lakes , Water Quality , Dissolved Organic Matter , Factor Analysis, Statistical , Humans , Humic Substances/analysis , Lakes/analysis , Spectrometry, Fluorescence
3.
World J Clin Cases ; 6(11): 441-446, 2018 Oct 06.
Article in English | MEDLINE | ID: mdl-30294608

ABSTRACT

AIM: To investigate the diagnostic value of abnormal serum carbohydrate antigen 199 (CA199) level in acute cholangitis secondary to choledocholithiasis. METHODS: In this retrospective cohort study, the clinical data of 727 patients with choledocholithiasis admitted to the Third Affiliated Hospital of Zunyi Medical College from June 2011 to June 2017 were collected. Among these patients, 258 patients had secondary acute cholangitis and served as observation group, and the remaining 569 choledocholithiasis patients served as the control group. Serum liver function indexes and tumor markers were detected in both groups, and the receiver operating characteristic (ROC) curves were constructed for markers showing statistical significances. The cutoff value, sensitivity, and specificity of each marker were calculated according to the ROC curves. RESULTS: The results of liver function tests showed no significant differences between the two groups (P > 0.05). Tumor markers including serum CA125, CA153, carcinoembryonic antigen, and alpha fetoprotein levels were also not significantly different (P > 0.05); however, the serum CA199 level was significantly higher in the observation group than in the control group (P < 0.05). The ROC curve analysis showed that the area under the curve was 0.885 (95%CI: 0.841-0.929) for CA199, and the cutoff value of 52.5 kU/L had the highest diagnostic accuracy, with a sensitivity of 86.8% and a specificity of 81.6%. CONCLUSION: Abnormally elevated serum CA199 level has an important value in the diagnosis of acute cholangitis secondary to choledocholithiasis. It may be a specific inflammatory marker for acute cholangitis.

4.
Chin Med J (Engl) ; 128(17): 2273-7, 2015 Sep 05.
Article in English | MEDLINE | ID: mdl-26315071

ABSTRACT

BACKGROUND: The prevalence of childhood asthma has been increasing in China. This study aimed to compare the prevalence, diagnosis, and treatment of asthmatic children from urban and rural areas in Beijing, China. METHODS: Schools, communities, and kindergartens were randomly selected by cluster random sampling from urban and rural areas in Beijing. Parents were surveyed by the same screening questionnaires. On-the-spot inquiries, physical examinations, medical records, and previous test results were used to diagnose asthmatic children. Information on previous diagnoses, treatments, and control of symptoms was obtained. RESULTS: From 7209 children in rural areas and 13,513 children in urban areas who completed screening questionnaires, 587 children were diagnosed as asthma. The prevalence of asthma in rural areas was lower than in urban areas (1.25% vs. 3.68%, χ2 = 100.80, P < 0.001). The diagnosis of asthma in rural areas was lower than in urban areas (48.9% vs. 73.9%, χ2 = 34.6, P < 0.001). Compared with urban asthmatic children (56.5%), only 35.6% of rural asthmatic children received inhaled corticosteroids (P < 0.05). The use of bronchodilators was also lower in rural areas than in urban areas (56.5% vs. 66.4%, χ2 = 14.2, P < 0.01). CONCLUSION: The prevalence of asthma in children was lower in rural areas compared with children in the urban area of Beijing. A considerable number of children were not diagnosed and inadequately treated in rural areas.


Subject(s)
Asthma/epidemiology , Adolescent , Adrenal Cortex Hormones/therapeutic use , Beijing/epidemiology , Child , Child, Preschool , China/epidemiology , Cross-Sectional Studies , Humans , Infant , Infant, Newborn , Male , Prevalence , Surveys and Questionnaires
5.
Zhonghua Yi Xue Za Zhi ; 93(8): 574-8, 2013 Feb 26.
Article in Chinese | MEDLINE | ID: mdl-23663334

ABSTRACT

OBJECTIVE: To explore the prevalence, diagnosis and management of childhood asthma in Beijing urban area. METHODS: Multi-stage, stratified and random cluster sampling was used to recruit children born during November 1, 1995 to October 31, 2010 from Beijing or other provinces but residing in Beijing for over half a year. The same screening questionnaires for the third national epidemiological survey of children's asthma were distributed to parents of children at schools, kindergartens and communities during October 2010 to March 2011. Asthmatic children were picked among the screening-positive children based on on-the-spot inquiries, physical examinations, medical records and supporting test results. Further survey of asthmatics was carried out to investigate the diagnosis and treatment status of childhood asthma and other associated allergic diseases. All data required double entry by Epi-Info 3.5.3 software and were processed by SPSS 19.0. RESULTS: Among a total of 14 085 questionnaires, 13 513 were completed with a response rate of 95.94%. And 497 (3.68%) children were diagnosed with typical (n = 451, 3.34%) and cough variant (n = 46, 0.34%) asthma. Among them, 40.64% (202/497) were newly diagnosed and 59.36% (295/497) had been previously diagnosed with asthma. The prevalence of asthma was higher in boys than in girls (4.80% (345/1790) vs 2.40% (152/6323), χ(2) = 54.446, P < 0.01). The asthma prevalence of preschoolers (3 - < 7 years old) was the highest (5.05% (180/3563)). In the past two years, the symptoms of 69.42% (345/497) children persisted and the current two-year prevalence of asthma was 2.55% (345/13513). Among the 295 children with previous asthma, only 46.44% (137/295) received inhaled corticosteroids according to the Global Initiative for Asthma (GINA) and 82.37% (243/295) of them used antibiotics. CONCLUSIONS: The prevalence of asthma is 3.68% in children under 14 years old in Beijing urban area and it varies in children with different genders and ages. A considerable number of children are not diagnosed or treated properly. And the management of asthma requires further improvement.


Subject(s)
Asthma/epidemiology , Adolescent , Child , Child, Preschool , China/epidemiology , Female , Humans , Infant , Infant, Newborn , Male , Prevalence
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