1.Investigation of Human Exposure Levels of Volatile Organic Compounds and Effects on Health
Xiang GAO ; Zhipeng BAI ; Yan YOU
Journal of Environment and Health 1992;0(04):-
Objective To investigate the exposure level of VOCs in different population and the health effects. Methods In 2005, a questionnaire survey relating to inhalation exposure assessment of VOCs and housing decoration characteristics was carried out in 200 newly decorated apartments (628 residents), 30 house decoration workers and 20 painting workers of an automobile manufacture factory. Indoor concentrations of formaldehyde, BTEX-compounds and TVOC were measured in typical apartments, offices, houses in where the decoration workers were operating, the painting workshops, and public indoor environments. Average daily exposure doses and potential doses for common people at home (non-occupational exposure group) and workers in occupational environments (occupational exposure group) to formaldehyde and BTEX-compounds and TVOC were estimated by combining the survey results with monitoring data. Results The percentages of whom having different discomfortable symptoms in the workers in the painting workshop were higher than that in common people (P
2.Radiation Protection of Low Dose CT Scanning in Orbit
Gang WANG ; Yan BAI ; Jiansi XIANG ; Shuqing ZHENG
Journal of Practical Radiology 2001;0(07):-
Objective To study radiation protection of low dose CT scanning in orbit. Methods 126 cases of orbital disease were scanned by original standard parameter (130 kV,100 mA) and two different low dose parameters (130 kV,50 mA and 30 mA) respectively. All the images were reconstructed by different Kernels. The image quality and difference of the CTDIw (weighted CT dose index) of each group were compared. Results CTDIw was 30% of that of the conventional scanning and least when 130 kV 30 mA,but the difference of the image quality compared with that by conventional scanning was highly statistical significance (P0.05). Conclusion Low dose CT scanning (50mA) in orbit not only can assure the image quality but also can decrease the radiation dose.
3.Recent advances in the study of a novel Omicron variant of SARS-CoV-2
HONG Zi-qiang ; SHENG Yan-nan ; JIN Da-cheng ; BAI Xiang-dou ; CUI Bai-qiang ; GOU Yun-jiu
China Tropical Medicine 2022;22(10):991-
Abstract: Due to the continued emergence of multiple variants of SARS-CoV-2, the ongoing pandemic has resulted in severe mortality over the past two years. After the Alpha, Beta, Gamma and Delta variants, the most recent new variant of concern (VOC) strain to emerge is Omicron (B.1.1.529), which evolved as a result of the accumulation of a large number of mutations. The Omicron variant, which has a much higher transmission rate than the Delta variant, soon replaced the Delta variant and others, is now the dominant variant worldwide. The emergence of Omicron poses new challenges for the prevention and control of COVID-19 and has raised a number of concerns worldwide. Recently, cases of Omicron infection have been reported in several parts of China, and therefore this paper provides a comprehensive analysis and summary of the epidemiology and immune escape mechanisms of the Omicron variant. We also suggest some therapeutic strategies against the Omicron variant, including rapid diagnosis, genome analysis of emerging variants, ramping up of vaccination drives and receiving booster doses, updating the available vaccines, designing of multivalent vaccines able to generate hybrid immunity, up-gradation of medical facilities and strict implementation of adequate prevention and control measures need to be given high priority to handle the on-going COVID-19 pandemic successfully.
5.Processing Technology Research of Fermentation and Purification of SUMO Protease UlP1
Xiu-Ping FENG ; Bai-Rong DU ; Dong-Mei YAN ; Xiang-Feng ZHAO ; Xun ZHU ;
China Biotechnology 2006;0(02):-
Nowadays,small peptides are always expressed in the form of fusion protein.The expression product contains many superfluous amino acids which can affect the biological functions of small peptides even expressed by GST fusion protein expression system.SUMO protease can cut SUMO fusion protein expressed by fusion expression system without any amino acid residues left on target protein thus become a hot topic in this field.Recombinant His-UlP1/pET3c/BL21(DE3)engineering strain was constructed by genetic engineering technology and the expression conditions were optimized in shake flaks.The process of high density fermentation was explored and different purification conditions were detected by chromatography.The results showed that SUMO protease could be expressed well after inducing the engineering strain by IPTG of 1.0mmol/L at 30℃ for 6 hours.The expression level of the strain in fermentation pots could reach 24.3% analyzed by SDS-PAGE.The purity of SUMO protease was more than 98% after further purification by cation exchange chromatography.The yield was 355mg SUMO protease per liter fermentation liquid.Western blot analysis demonstrated that there were immune reactions between IlP1 and 6?His antibodies,so it has established a good foundation for large-scale industralazation in the future.
6.Effects of aluminum on the intracellular calcium concentration and the expression of calcium channels in the hippocampus of rats
Rui, REN ; Yang, ZHANG ; Xiao-feng, ZHANG ; Yan-ping, WU ; Bai-xiang, LI
Chinese Journal of Endemiology 2009;28(5):501-504
Objective To dynamically investigate the effects of aluminum on the concentration of free intracellular Ca2+([Ca2+]i) and the expression of calcium channels in the hippocampus of rats. Methods Healthy 64 Wistar rats were taken as the experimental objects. And these rats were randomly divided into 16 groups according to their weights, and were instilled with AlCl3 at 0(control),37.3,74.7 and 248.7 mg/kg respectively. The experimental time exposed to AlCl3 was 45,75,120 d, among which the rats were given AlCl3 for 120 d fed normally for 30 d. The hippoeampus were segregated on day 45,75,120 and 150 d and the[Ca2+]i of hippocampus of rats were detected by fluorospectrophotometer. The expression of Ryanodine receptor 2 (RyR2) mRNA and α1C ubunit of L-type calcium ehannels(L-Ca2+α1C) mRNA were detected by RT-PCR analysis. Results [Ca2+]i was increased by AlCl3 in a dose-and time-dependant manner(F=23.136 and 19.089, P<0.01). There was a synergistic effect between the dose and time in [Ca2+]i (F=2.270, P<0.05). In time of 120,150 days, the [Ca2+]i of rats hippocampus in 37.3[(299.3±48.7), (342.7±35.3)nmol/L], 74.7[(391.2±47.9), (408.1±42.8)nmol/L] and 248.7 mg/kg group[(397.9±55.8), (405.2±22.7)nmol/L] significantly increased compared with control group [(195.1±29.9), (209.1±30.6)nmol/L; P<0.01]. The expression of RyR2 mRNA and L-Ca2+α1C mRNA were increased by AlCl3(F=23.301 and 60.812, P<0.01). The experimental time could lower the expression of L-Ca2+ α1C mRNA (F=6.088, P<0.01), but had no influences on the expression of RyR2 mR NA (F=1.361, P>0.05). There was interaction between the dose of AlCl3 and the time in the expression of L-Ca2+α1C mRNA (F=5.876,P< 0.01). On day 75,120 and 150 of the experiment, the expression of L-Ca2+α1C mRNA in rat hippocampus of 74.7 (1.03±0.16,1.18±0.18,0.92±0.11) and 248.7 mg/kg group(1.89±0.26, 1.25±0.10, 1.07±0.14) also increased compared with control group(0.63±0.09,0.78±0.16,0.69±0.11; P<0.05 or <0.01). On day 45,75, 120 and 150 of the experiment, the expression of RyR2 mRNA in 74.7(0.49±0.06,0.51±0.07,0.57±0.11, 0.47±0.11), 248.7(0.47±0.03,0.52±0.09, 0.70±0.10, 0.78±0.09)mg/kg AlCl3 groups was highly increased compared with control group (0.24±0.07, 0.32±0.04, 0.30±0.06, 0.27±0.06; P<0.05 or<0.01). Conclusion Al increases [Ca2+]i by increasing the expression of the RyR2 mRNA and L-Ca2+α1C mRNA, thus exerts an irreversible neuronal toxicity.
7.Effect of aluminum on concentration of calcium in cells of the cerebral cortex.
Rui REN ; Bai-xiang LI ; Yang ZHANG ; Xiao-feng ZHANG ; Shu-ying GAO ; Yan-ping WU
Chinese Journal of Industrial Hygiene and Occupational Diseases 2006;24(3):182-183
Aluminum
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toxicity
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Animals
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Animals, Newborn
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Calcium
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metabolism
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Cerebral Cortex
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drug effects
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metabolism
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Dose-Response Relationship, Drug
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Female
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Male
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Rats
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Rats, Wistar
8.Relationship Between PET/CT Maximum Standardized Uptake Value, Tumor Markers and Prognosis of Lung Cancer
Xiaoyi DUAN ; Lu BAI ; Yan LI ; Weishan ZHANG ; Xiang LIU ; Yang LI ; Youmin GUO
Chinese Journal of Medical Imaging 2015;23(8):582-586
Purpose To compare the relationship between the maximum standardized uptake value (SUVmax) of PET/CT imaging and tumor markers in lung cancer, and to provide evidence for the comprehensive assessment of non small cell lung cancer. Materials and Methods The results of PET/CT imaging, serum carcinoembryonic antigen (CEA), cytokeratin-19 fragment antigen 21-1 (CYFRA21-1) and neuronspecific enolase (NSE) of 179 patients with non small cell lung cancer were analyzed, subjects were then divided into different groups according to their clinical features and pathological types, the differences of SUVmax and tumor markers'' level were compared between different groups, and their correlations with tumor histological type, differentiation and the clinical stages were also analyzed.Results SUVmax of the tumor was related with lesion size,≥3 cm tumors'' SUVmax were significantly higher than that of <3 cm tumors (P<0.01), SUVmax and serum NSE level were related with tumor differentiation, and these in low differentiation group were higher than those in high and medium differentiation group (P<0.05,P<0.01). In addition, SUVmax, CEA, CYFRA21-1 and NSE had no correlation with gender, age, pathological type and clinical stage (P>0.05).Conclusion SUVmax and NSE have a certain relationship with tumor differentiation in non small cell lung cancer patients, thus can be used as a reference index for prognosis of indirect prediction of lung cancer.
9.Correlations between quality indexes of chest compression
Feng-Ling ZHANG ; Li YAN ; Su-Fang HUANG ; Xiang-Jun BAI
World Journal of Emergency Medicine 2013;4(1):54-58
BACKGROUND: Cardiopulmonary resuscitation (CPR) is a kind of emergency treatment for cardiopulmonary arrest, and chest compression is the most important and necessary part of CPR. The American Heart Association published the new Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care in 2010 and demanded for better performance of chest compression practice, especially in compression depth and rate. The current study was to explore the relationship of quality indexes of chest compression and to identify the key points in chest compression training and practice.METHODS: Totally 219 healthcare workers accepted chest compression training by using Laerdal ACLS advanced life support resuscitation model. The quality indexes of chest compression, including compression hands placement, compression rate, compression depth, and chest wall recoil as well as self-reported fatigue time were monitored by the Laerdal Computer Skills and Reporting System.RESULTS: The quality of chest compression was related to the gender of the compressor. The indexes in males, including self-reported fatigue time, the accuracy of compression depth and the compression rate, the accuracy of compression rate, were higher than those in females. However, the accuracy of chest recoil was higher in females than in males. The quality indexes of chest compression were correlated with each other. The self-reported fatigue time was related to all the indexes except the compression rate.CONCLUSION: It is necessary to offer CPR training courses regularly. In clinical practice, it might be better to change the practitioner before fatigue, especially for females or weak practitioners. In training projects, more attention should be paid to the control of compression rate, in order to delay the fatigue, guarantee enough compression depth and improve the quality of chest compression.
10.Preparation of curcumin-EC sustained-release composite particles by supercritical CO2 anti-solvent technology.
Wei-li BAI ; Ting-yuan YAN ; Zhi-xiang WANG ; De-chun HUANG ; Ting-xuan YAN ; Ping LI
China Journal of Chinese Materia Medica 2015;40(2):226-230
Curcumin-ethyl-cellulose (EC) sustained-release composite particles were prepared by using supercritical CO2 anti-solvent technology. With drug loading and yield of inclusion complex as evaluation indexes, on the basis of single factor tests, orthogonal experimental design was used to optimize the preparation process of curcumin-EC sustained-release composite particles. The experiments such as drug loading, yield, particle size distribution, electron microscope analysis (SEM) , infrared spectrum (IR), differential scanning calorimetry (DSC) and in vitro dissolution were used to analyze the optimal process combination. The orthogonal experimental optimization process conditions were set as follows: crystallization temperature 45 degrees C, crystallization pressure 10 MPa, curcumin concentration 8 g x L(-1), solvent flow rate 0.9 mL x min(-1), and CO2 velocity 4 L x min(-1). Under the optimal conditions, the average drug loading and yield of curcumin-EC sustained-release composite particles were 33.01% and 83.97%, and the average particle size of the particles was 20.632 μm. IR and DSC analysis showed that curcumin might complex with EC. The experiments of in vitro dissolution showed that curcumin-EC composite particles had good sustained-release effect. Curcumin-EC sustained-release composite particles can be prepared by supercritical CO2 anti-solvent technology.
Carbon Dioxide
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chemistry
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Cellulose
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administration & dosage
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analogs & derivatives
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chemistry
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Curcumin
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administration & dosage
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chemistry
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Delayed-Action Preparations
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Solubility
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Solvents
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Technology, Pharmaceutical