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1.
Environ Res ; 252(Pt 3): 119009, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38679277

ABSTRACT

Fine particulate matter (PM2.5) harms human health and hinders normal human life. Considering the serious complexity and obvious regional characteristics of PM2.5 pollution, it is urgent to fill in the comprehensive overview of regional characteristics and interannual evolution of PM2.5. This review studied the PM2.5 pollution in six typical areas between 2014 and 2022 based on the data published by the Chinese government and nearly 120 relevant literature. We analyzed and compared the characteristics of interannual and quarterly changes of PM2.5 concentration. The Beijing-Tianjin-Hebei region (BTH), Yangtze River Delta (YRD) and Pearl River Delta (PRD) made remarkable progress in improving PM2.5 pollution, while Fenwei Plain (FWP), Sichuan Basin (SCB) and Northeast Plain (NEP) were slightly inferior mainly due to the relatively lower level of economic development. It was found that the annual average PM2.5 concentration change versus year curves in the three areas with better pollution control conditions can be merged into a smooth curve. Importantly, this can be fitted for the accurate evaluation of each area and provide reliable prediction of its future evolution. In addition, we analyzed the factors affecting the PM2.5 in each area and summarize the causes of air pollution in China. They included primary emission, secondary generation, regional transmission, as well as unfavorable air dispersion conditions. We also suggested that the PM2.5 pollution control should target specific industries and periods, and further research need to be carried out on the process of secondary production. The results provided useful assistance such as effect prediction and strategy guidance for PM2.5 pollution control in Chinese backward areas.


Subject(s)
Air Pollutants , Air Pollution , Environmental Monitoring , Particulate Matter , Particulate Matter/analysis , China , Air Pollution/analysis , Air Pollutants/analysis , Environmental Monitoring/methods , Quality Improvement , Particle Size
2.
PeerJ ; 11: e15268, 2023.
Article in English | MEDLINE | ID: mdl-37214095

ABSTRACT

Background: The prevalence of Helicobacter pylori (H. pylori) keeps rising while the eradication rate continues to decline due to the increasing antibiotic resistance. Regional variations of antimicrobial resistance to H. pylori have been recommended by guidelines in recent years. This study aims to investigate the antibiotic resistance rate of H. pylori and its association with infected subjects' characteristics in Liaoning Province, an area in north China. Methods: Gastric tissues from 178 H. pylori positive participants without previous antibiotic use within four weeks were collected for H. pylori culture. Antibiotic susceptibility to furazolidone (AOZ), tetracycline (TC), levofloxacin (LFX), metronidazole (MET), clarithromycin (CLA), and amoxicillin (AMX) were examined with the agar dilution method. Associations between H. pylori resistance and patient characteristics were further analysed. Results: No resistance was observed in AOZ or TC. For LFX, MET, CLA, and AMX, the overall resistance rates were 41.10%, 79.14%, 71.78%, and 22.09% respectively. There were significant differences between resistance to CLA and MALToma (P = 0.021), and between resistance to MET and age (P < 0.001). Conclusions: The primary resistant rates of LEX, MET, CLA, and AMX were relatively high in Liaoning. Treatment effectiveness improvement could be achieved by prior antimicrobial susceptibility tests before antibiotic prescription.


Subject(s)
Helicobacter Infections , Helicobacter pylori , Humans , Helicobacter Infections/drug therapy , Drug Resistance, Bacterial , Anti-Bacterial Agents/pharmacology , Clarithromycin/pharmacology , Metronidazole , Amoxicillin , Levofloxacin/pharmacology , Tetracycline/pharmacology , China/epidemiology , Risk Factors
3.
J Sep Sci ; 43(7): 1284-1296, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31916672

ABSTRACT

Agarwood, a species of resinous heartwood, is a precious medicinal plant and a type of rare natural spice, which is widely used in medicine, cosmetics, religious activities, and other fields. In this study, agarwood samples from eight different regions across four countries were analyzed by comprehensive two-dimensional gas chromatography-quadrupole time-of-flight mass spectrometry. A total of 232 species were identified (the match factors of these compounds were above 750). The main compounds of agarwood are oxygenated sesquiterpenes and chromones. The compositions of India1 and Malaysia2 were significantly different from those of other samples, which might be attributed to the different production processes of agarwood. For further investigation, factor analysis was conducted for six agarwood samples. The results showed that the data classification possessed a regional characteristic; according to the retention time and relative content, characteristic compositions were determined by factor scores. Finally, the differences of characteristic compositions were simply analyzed, and the reasons were speculated.


Subject(s)
Chromones/analysis , Sesquiterpenes/analysis , Thymelaeaceae/chemistry , Gas Chromatography-Mass Spectrometry/instrumentation
4.
Zhongguo Zhong Yao Za Zhi ; 41(10): 1797-1802, 2016 May.
Article in Chinese | MEDLINE | ID: mdl-28895323

ABSTRACT

In the present research, 674 wild medicinal material samples of Phellodendri amurensis Cortex were collected from 31 sampling sites in the whole distribution of its original plant Phellodendron amurense. The samples were collected under the premise that the stem diameter of sampling plant, sampling position and time were controlled. And the sampling sites were set at the interval of a latitude. The content of 6 kinds of active ingredients, palmatine chloride, berberine hydrochloride, phellodendrine chloride, jatrorrhizine hydrochloride, magnoflorine, chlorogenic acid, etc in the medicinal material samples were determined, and the results showed that the content of most active ingredients in the medicinal materials showed significant differences due to the difference of sampling sites. Among them, the medicinal materials from Liaoning region had the highest content of active ingredients, followed by Beijing and Jilin regions, and that from Heilongjiang region had the lowest content. The study has important directive significance to the exploration of environmental factors for the formation of active constituent and artificial planting regionalization of high quality Phellodendri amurensis Cortex.


Subject(s)
Alkaloids/analysis , Chlorogenic Acid/analysis , Phellodendron/chemistry , Berberine , Berberine Alkaloids , China , Drugs, Chinese Herbal , Plants, Medicinal/chemistry
5.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-250487

ABSTRACT

In the present research, 674 wild medicinal material samples of Phellodendri amurensis Cortex were collected from 31 sampling sites in the whole distribution of its original plant Phellodendron amurense. The samples were collected under the premise that the stem diameter of sampling plant, sampling position and time were controlled. And the sampling sites were set at the interval of a latitude. The content of 6 kinds of active ingredients, palmatine chloride, berberine hydrochloride, phellodendrine chloride, jatrorrhizine hydrochloride, magnoflorine, chlorogenic acid, etc in the medicinal material samples were determined, and the results showed that the content of most active ingredients in the medicinal materials showed significant differences due to the difference of sampling sites. Among them, the medicinal materials from Liaoning region had the highest content of active ingredients, followed by Beijing and Jilin regions, and that from Heilongjiang region had the lowest content. The study has important directive significance to the exploration of environmental factors for the formation of active constituent and artificial planting regionalization of high quality Phellodendri amurensis Cortex.

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