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Volatile organic compounds (VOCs) do great harm to human health, and also have some impact on air quality. Cooking is one of the important sources of VOCs, so the study of cooking emissions is of great significance. By simulating the heating of oil and cooking, the characteristics and chemical composition of VOCs emissions for different types of oil fumes were analyzed by gas chromatography-mass spectrometry (GC-MS), using different oils, seasonings, and dishes as variables. The results show that the emission factors of the oils range from 0.81 to 2.53 g·kg -1 , and the emissions are dominated by halogenated hydrocarbons and alkanes. The emission factors of the seasonings range from 25.06 to 40.18 g·kg -1 , and the seasonings mainly emit alkanes. The quantity of emissions from chili fried meat is much higher than that of tomato scrambled eggs, and the chili fried meat mainly emits halogenated hydrocarbons, while tomato scrambled eggs mainly emit aromatic hydrocarbons and alkanes.

RNA interference has been considered as an effective gene silencing method in basic and preclinical investigations. The aims of the present study were to construct a lentiviral vector expressing a short hairpin RNA (shRNA) targeting the murine CC chemokine receptor 3 (mCCR3), and to investigate its effects on the proliferation and apoptosis of mouse eosinophils. A recombinant lentiviral vector expressing four fragments of mouse CCR3 shRNA (pLVX‑mCCR3‑1+2+3+4‑shRNA) was constructed using subcloning techniques. This novel lentivirus was then packaged into 293T cells by co‑transduction with plasmids, including Baculo p35, pCMV R8.2 and VSV. The interference effects of the vector were verified using polymerase chain reaction (PCR) and western blot analyses. The effects of the interference on the proliferation and apoptosis of mouse eosinophils were investigated using 3‑(4,5‑dimethylthiazol‑2‑yl)‑5‑(3‑carboxymethoxyphenyl)‑2‑(4‑sulfophenyl)‑2H‑tetrazolium and terminal deoxynucleotidyl transferase dUTP nick end labeling methods, respectively. The results of the PCR and western blot analyses confirmed that the novel recombinant vector, pLVX‑mCCR3‑1+2+3+4‑shRNA, had high efficiency in inhibiting the mRNA and protein expression levels of mCCR3 in mouse eosinophils. The downregulation of mCCR3 significantly inhibited proliferation of the eosinophils. Furthermore, the present study found that the downregulation of mCCR3 significantly promoted apoptosis of the eosinophils. Therefore, the downregulation of mCCR3 led to the inhibition of proliferation and induction of apoptosis in mouse eosinophils. The predominant characteristics of allergic rhinitis are eosinophil infiltration and release of inflammatory mediators, which appear in a variety of clinical manifestations. The results of the present study indicate that mCCR3 silencing may serve as a putative approach for the treatment of allergic rhinitis.

Objective: Through construction of a lentiviral expression vector of chemokine receptor 3 (CCR3)RNA interference (RNAi) of mouse, to further study the function of CCR3 gene on eosinophils., Methods: Focused on the CCR3 gene sequences, RNAi target sequences were designed, then the target sequences of Oligo DNA were synthesized and annealed to double stranded DNA, which was subsequently connected to pLVX-shRNA2-m vector digested by MluI, SacI, EcoRI, HindIII, BamHI and Xho I, short hairpin RNA lentiviral vectors were constructed. Short hairpin RNA lentiviral vectors were constructed. 293T cells and eosinophils were transfected by shRNA lentiviral vector, and virus titer was determined. The expression of the CCR3 gene in eosinophils was identified by quantitative-PCR., Results: The lentiviral vector of shRNA-mCCR3-oligonucleotide chain was inserted correctly. Infection efficiency of 293T cells observed under fluorescence microscope was more than 90%, the virus titer was 4×10(8) TU/ml. CCR3 interference rate was 86.7%., Conclusion: A lentiviral vector of CCR3-gene RNAi was constructed successfully by the genetic engineering technology, and it provides a condition for further research in vitro and vivo.

Objective: To investigate the influence of inhaled glucocorticoid on the pathological change of the nasal mucosa in allergic rhinitis., Methods: One hundred and eighty Sprague-Dawley (SD) rats were selected. According to the random number table, these animals were randomly divided into two groups: the control Group A and the experimental group. There were 60 rats in Group A and 120 rats in experimental group. First of all, the rats in experimental group were sensitized by intra-peritoneal injection with ovalbumin (OVA), enhanced and local stimulated. Next, the rats in the experimental group were randomly divided into B and C groups. The number of rats in each group was 60. Group B still had the intranasal dropping on each side with OVA in the same volume and concentration twice a week. The rats in Group C also had the intranasal dropping on each side with OVA in the same volume and concentration twice a week. But, at the same time, these animals had fluticasone propionate (FP) nasal spray each side 50 microl/per day. While doing intra-peritoneal injection with physiological saline in the same volume and intranasal dropping on the rats in normal Group A. Ten rats from each group were randomly selected to be killed at the end of first, second, fourth, eighth, twelfth and sixteenth weeks after treatment. One from the ten rats in each group was used for micro-vascular casting of nasal mucosa, and the remaining nine were used for pathological examination., Results: The model of the rats in experimental group was established successfully. After allergen stimulation, the nasal mucosa showed metaplasia of the goblet cells, epithelial denudation, inflammatory cells infiltration especially eosinophils, hyperplasia of the number of gland and density of micro-blood vessels. The capillary became netted. Cilia of epithelial shed to different extent and were uneven, and the layers of reticular formation of basal membrane became thick, and collagen deposition and fabric hyperplasia were seen under the electron microscope. In Group B, due to continuously contact with allergen, the mucosa remodeling enhanced. In Group C, glucocorticoid controlled the symptoms of allergic rhinitis better, but the cilia of epithelial shed, metaplasia of the goblet cells, inflammatory cells infiltration, hyperplasia of gland and micro-blood vessels, collagen deposition and fabric hyperplasia also could be seen in rat nasal mucosa., Conclusions: The pathological change of the nasal mucosa was found in allergic rhinitis. If the allergen was continuously contacted, the pathological change aggravated. Glucocorticoid could control the symptoms of allergic rhinitis better and reverse the mucosa pathological change to some extent, but it could not retro-converse or repair the nasal mucosa while the irreversibile change had occurred.

Objective: To investigate hepatitis B virus (HBV) subtypes in patients chronically infected with genotype B or C of hepatitis B virus in Guizhou and to study the relationship between the subtypes and the progression of their liver diseases., Methods: Using PCR, 309 bp gene fragments in the HBV p region were amplified. The products of PCR were digested by VspI, NciI, BstEII and subjected to agarose gel electrophoresis. The subtypes of C1 and C2 were detected by restriction fragment length polymorphism (RFLP). B subtype was determined by direct sequencing of PCR product. One hundred seventy-eight patients with genotype B or C HBV infection in Guizhou, including 50 asymptomatic carriers (ASC), 100 chronic hepatitis (CHB), 14 liver cirrhosis (LC), and 14 hepatocellular carcinoma (HCC) patients were examined. The relationship between HBV C subtypes and the progression of their liver diseases was studied by analyzing the HBeAg positivity, HBV DNA loads and ALT levels of the patients., Results: Of 84 patients with HBV genotype C, 27 (32.14%) and 56 (66.67%) were subtype C1 and C2, respectively. In 94 genotype B, 93 (98.94%) were subtype Ba and only one was subtype Bj. Subtype C1 showed a trend of gradual decrease from ASC and CHB to LC/HCC groups. In contrast, subtype C2 showed a gradual increase (trend) in the same order. The HBeAg positivity was significantly lower in subtype C1 than that in subtype C2. The ALT levels and HBV DNA loads were higher in patients with subtype C2 than those in subtype C1, however no statistical significance was found in these primes (t=0.95, 0.79)., Conclusion: Subtype Ba is major and subtype C2 is more common in Guizhou. The distribution of subtype C1 and C2 are different in various stages of liver disease. The PCR-RFLP method is simple and accurate and can be used in a large-scale survey.

Objective: To establish a mismatched polymerase chain reaction restricted fragment length polymorphism (mPCR-RFLP) method for detection of hepatitis B virus (HBV) mutation in precore A1896, and compare with direct sequencing for evaluating its applicability., Methods: According to the principle of mPCR, 194bp gene fragments in HBV precore region was amplified. The products of PCR were digested by Bsu36I and subjected to agarose gel electrophoresis. A method for detecting procore A1896 mutation was established by restricted fragment length polymorphism. Totally 134 sera were analyzed by both mPCR-RFLP and direct sequencing methods. Two sera which were identified having mixed infection with precore wild and mutant strains by mPCR-RFLP also were analyzed by cloning and sequencing., Results: From 134 sera, 117 could be analyzed for HBV precore 1896 situation by mPCR-RFLP method, 109 could be analyzed by sequencing. In 101 sera which could be analyzed by the two methods, 54 were mutant strains and 47 were wild strains. The results of both methods were completely compatible. There was no significant difference in detective rate of HBV precore A1896 mutation between the two methods. The sequences of five clones from one serum which was identified precore mutant by mPCR-RFLP were all A1896 mutant strains. Another serum was identified as mixed infection by mPCR-RFLP, one clone was A1896 mutant strain and four were G1896 wild strains. The results of mPCR-RFLP were verified by cloning., Conclusion: Compared with sequencing, the mPCR-RFLP method is simple, accurate and can be used in large-scale surveys and clinical research.

Objective: To investigate the distribution of hepatitis B virus (HBV) precore A1896 and basic core promoter (BCP)T1762/A1764 mutations in Guizhou area., Methods: 482 patients with chronic HBV infection, belonging to 4 nationalities, including 225 asymptomatic carriers (ASC), 158 chronic hepatitis (CH), 57 liver cirrhosis (LC), 42 hepatocellular carcinoma (HCC), from 4 areas of Guizhou province were examined. HBV A1896 and T1762/A1764 mutations were determined by direct sequencing and restriction fragment length polymorphism (RFLP). HBV genotypes were determined by PCR-RFLP based on S gene. The relationship among these mutations and genotype and the progression of liver disease were studied by multi-normal logistic regression analysis., Results: A1896 and T1762/A1764 mutations were detected 23.03% and 29.67% among 482 patients. These mutations were more prevalent in Hans than in Dong, Miao and Buyi minorities (P < 0.01, respectively). The mutations of A1896 and T1762/ A1764 were more commonly seen in HBeAg negative than in HBeAg positive patients (P < 0.01, respectively). The mutation of T1762/A1764 was significantly higher in genotype C than in genotype B (P < 0.01). There were significantly statistical differences in the detective rate of A1896 and T1762/ A1764 mutations between patients with HCC, LC and CH, ASC. The distribution of these mutations in Guiyang (31.79% and 41.06%) was higher than in Zunye (10.94%, 14.06%), Duyun (8.64%, 11.11%) or Kaili (2.86%, 2.86%). However, there was no statistical difference by multi-normal logistic regression analysis after controlling the influence of HBeAg statu, genotype and clinical types., Conclusion: The distributions of A1896 and T1762/A1764 mutations were different in some nationalities of Guizhou province. The mutation of T1762/A1764 was more commonly seen in genotype C than in genotypr B. These mutations were closely related to progression of chronic liver diseases. Hepatitis B virus; Genotype; Restriction fragment length polymorphism

Objective: To study the relationships between hepatitis B virus (HBV ) pre-S region mutations and their genotypes and the stages of liver disease of the patients., Methods: The entire HBV pre-S1 and pre-S2 genes were amplified by polymerase chain reaction (PCR). The amplified products were digested by NlaIII restriction enzyme. A detecting method for pre-S2 start codon mutation was established according to the restriction fragment length polymorphism (RFLP) analysis. Pre-S region deletion was revealed by polyacrylamide gel electrophoresis (PAGE). Fourteen sera having pre-S deletions or pre-S2 start codon mutations and wild strains were directly sequenced. HBV genotypes were determined by RFLP based on S-gene PCR products. One hundred sixty serum samples were collected from patients with HBV related diseases and they were determined by the above methods. The relationships between HBV pre-S region mutations and their genotypes and the stages of liver disease of the patients were analysed., Results: Of the 160 sera, genotype B and C were identified in 81 and 79 respectively. The detected ratios of pre-S2 start codon and pre-S deletion mutations were significantly higher in genotype C than in genotype B (43.04% vs 1.23%, 36.71% vs 19.75%, P<0.05, respectively). The detection rates of pre-S2 start codon mutation were significantly different in different groups: from 50.00% (HCC), 39.47% (LC), 8.00% (CH), to ASC (0). The detection rates of pre-S deletion mutations among patients with HCC (53.13%), LC (42.11%), CH (18.00%) and ASC (7.50%) also varied significantly. The results obtained from sequencing and PCR-RFLP/PAGE were completely compatible. Multivariate analysis indicated that genotype C (OR=6.26, P<0.01) and advanced liver disease (OR=11.99, P<0.01) were significant variables for pre-S mutations development., Conclusion: The pre-S2 start codon and pre-S deletion mutations are more common in genotype C than in genotype B. These mutations are closely related to the progression of liver disease.

Objective: To investigate the distribution of hepatitis B virus (HBV) genotype in Guizhou and to study the relationship between the genotype and the progression of liver disease., Methods: 786 patients with chronic HBV infection, from 4 cities of Guizhou, including 346 asymptomatic carriers (ASC), 313 chronic hepatitis (CH), 77 liver cirrhosis (LC), 50 hepatocellular carcinoma (HCC) were examined. HBV genotype was determined by restriction fragment length polymorphism analysis and the subtypes were determined by direct sequencing of PCR product in 94 patients with HBV B genotype, the relationship between HBV genotype and the progression of liver disease was studied by multifactor analysis such as HBeAg positivity, HBV DNA load and ALT level., Results: Of the 786 patients, 7 (0.89%), 497 (63.23%), 275 (34.99%), and 7 (0.89%) belonged to genotype A, B, C, D, respectively. There was statistically significant difference in the distribution of genotype B among Kaili (96.04%), Zunyi (78.79%), Duyun (64.52%) and Guiyang (53.14%) (P< 0.01). Genotype C was more prevalent in Guiyang than in other three cities (P < 0.01, or P < 0.05). Out of 94 genotypes B, 93 (98.94%) belonged to subtype Ba, only one was subtype Bj. There were statistically significant difference in the distribution of genotype B and C among various stage of liver disease (P < 0.05 or P < 0.01). Genotype B showed a gradual decrease from ASC, CH, LC to the HCC group while in contrast, genotype C showed a gradual increase in the same order. The ALT levels and the mean age were significantly higher and older in patients with genotype C than those in genotype B (P < 0.01 or 0.05). The HBeAg positivity was significantly lower in genotype C than that in genotype B (P < 0.025)., Conclusion: Data showed that there were genotype A, B, C and D existing in Guizhou. Genotype B was the major one but genotype C was more commonly seen. In genotype B, subtype Ba appeared to be predominant. The geographic distribution of genotype B and C were different in some cities of Guizhou. Compared to genotype B, genotype C was associated with the development of more severe liver damage.