Publications (24)28.05 Total impact
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Article: Depletion of Bmi-1 enhances 5-fluorouracil-induced apoptosis and autophagy in hepatocellular carcinoma cells.
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ABSTRACT: 5-fluorouracil (5-FU) is one of the standard chemoradiotherapy regimens for hepatocellular carcinoma (HCC) treatment. B-cell-specific Moloney murine leukemia virus insertion site 1 (Bmi-1) has been demonstrated to regulate proliferation. Additionally, Bmi-1 overexpression has been identified in HCC cell lines and correlates with the advanced invasive stage of tumor progression and poor prognosis. In this study, we examined the effects of 5-FU treatment on cell growth in HCC cells with or without Bmi-1 depletion. The IC(50) values of 5-FU were significantly decreased to a greater extent in cells with Bmi-1 knockdown. Depletion of Bmi-1 increased sensitivity of the cells to 5-FU and increased apoptosis. Knockdown of endogenous Bmi-1 led to a substantial reduction in the levels of phospho-AKT and Bcl-2 with a concomitant increase in the levels of Bax. Additionally, 5-FU induced the conversion/turnover of microtubule-associated protein 1 light chain 3 (LC3). Knockdown of endogenous Bmi-1 led to an increase in the levels of Beclin-1 and the accumulation of LC3-II. Together, these findings reveal that Bmi-1 depletion enhanced the chemosensitivity of HCC cells by inducing apoptosis and autophagy, which is associated with the PI3K/AKT and Bcl-2/Beclin-1 pathways.Oncology letters 10/2012; 4(4):723-726. · 0.11 Impact Factor -
Article: A method for the establishment of a cell line with stable expression of the GFP-LC3 reporter protein.
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ABSTRACT: As the function of autophagy becomes evident in a number of diseases, including cancer and infection, it is crucial to construct macrophage cell lines with stable expression of the microtubule-associated protein light chain 3 (GFP-LC3). In this study, a mouse LC3 open-reading frame was amplified by RT-PCR, and cloned into the pEGFP-C1 plasmid for expression of the GFP-LC3 fusion protein. The recombinant plasmid was transfected into RAW264.7 cells using Lipofectamine 2000 reagent and stably transfected clones were selected by G418 screening. Autophagic puncta formation was observed by fluorescense microscopy. Additionally, we found that starvation treatment induced a significant increase in the number of autophagosomes, while wortmannin treatment significantly repressed the formation of autophagosomes. This study indicated that the RAW264.7 cell line stably expressing GFP-LC3 is available for use in a GFP-LC3 puncta formation assay, and may contribute to basic investigations of autophagic function or drug screening targeted at autophagy.Molecular Medicine Reports 07/2012; 6(4):783-6. · 0.42 Impact Factor -
Article: [Immune regulation of T-bet adjuvant on Ag85B DNA vaccine against Mycobacterium tuberculosis].
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ABSTRACT: To construct a novel Ag85B DNA vaccine based on the genetic adjuvant of T-bet known as Th1 transcription factor and to research the immunoregulation function of the DNA complex vaccine. Ag85B gene and T-bet gene were amplified by RT-PCR, and cloned into pcDNA3.1 plasmid to construct recombinant plasmids pcDNA3-Ag85B and pcDNA3-T-bet, respectively. The recombinant plasmids were transfected into RAW264.7 cells using Lipofectamine(TM); 2000 reagent to detect the expressions of Ag85B and T-bet proteins by Western blotting. BALB/c mice were immunized by three intramuscular inoculations with pcDNA3.1-FLAG-T-bet in combination with pcDNA3.1-FLAG-Ag85B. Two weeks after the last immunization, the anti-Ag85B antibody titres in sera were tested by ELISA. Meanwhile, spleen lymphocyte suspension was cultured in the context of Ag85B, and then the secretion of cytokines in the culture fluid was tested by ELISA. Plasmid proteins were successfully expressed in a dose-dependent manner. Additionally, T-bet/Ag85B complex not only induced obviously higher IgG2a titre with the lower IgG1, but also stimulated the increased secretion of IFN-γ and IL-2 with the concomitant repression of IL-4 and IL-10. T-bet can enhance Ag85B-specific IgG2a antibody response and convert T cell subsets to a Th1-predominant immune response.Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology 07/2012; 28(7):680-3. -
Article: T-bet acts as a powerful adjuvant in Ag85B DNA‑based vaccination against tuberculosis.
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ABSTRACT: Owing to the limitations of traditional Bacillus Calmette-Guerin vaccines and the low efficacy of DNA vaccines expressing single antigens of Mycobacterium tuberculosis, there is a pressing requirement for adjuvants capable of strengthing the immunogenicity and effectiveness of these vaccines against tuberculosis (TB). T-bet (TBX21) is a transcription factor, which controls the optimal development of type-1 immune responses responsible for the potent protection of vaccines against TB. However, little is known about the efficiency of the TB vaccine combined with T-bet. In this study, we report an approach to intensify the immunogenicity of Ag85B DNA-based vaccines using T-bet as an adjuvant. Balb/c mice were immunized by 3 intramuscular inoculations with pcDNA3.1-FLAG-T-bet in combination with pcDNA3.1-FLAG-Ag85B, and the immune responses were compared with those induced by vaccination with Ag85B DNA alone. We found that pcDNA3.1-T-bet-Ag85B not only induced evidently higher IgG2a antibody responses, but also increased the production of interferon-γ (IFN-γ) and interleukin (IL)-2 with the concomitant repression of IL-4 and IL-10 compared with pcDNA3.1-Ag85B alone or the empty vector. Thus, plasmid DNA coding for T-bet enhanced Ag85B-specific immune responses and shifted them to a predominant Th1-type immune response. In conclusion, T-bet is an efficacious Th1-inducing adjuvant in the context of the Ag85B DNA-based vaccination, and could also prove to be a promising candidate for DNA vaccine development against TB.Molecular Medicine Reports 04/2012; 6(1):139-44. · 0.42 Impact Factor -
Article: Gene/protein expression level, immunolocalization and binding characteristics of fatty acid binding protein from Clonorchis sinensis (CsFABP).
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ABSTRACT: Clonorchis sinensis fatty acid-binding protein (CsFABP) belongs to a multigene family of lipid-binding proteins and is considered to be a promising vaccine candidate for human clonorchiasis. In this study, binding characteristics of CsFABP have been examined for the first time. The recombinant CsFABP (rCsFABP) was found to bind 11-(dansylamino) undecanoic acid (DAUDA), causing a blue shift in the fluorescence emission from 543 to 531 nm with an excitation wavelength of 345 nm and a substantial increase in fluorescence intensity. Fluorimetric titration of rCsFABP with DAUDA exhibited an apparent dissociation constant (K (d)) of 1.58 ± 0.14 μM. In the competitive experiment, the rCsFABP efficiently bound saturated C(10)-C(18) fatty acids and unsaturated fatty acids (oleic acid and linoleic acid), and the latter presented the higher affinity. Furthermore, quantitative RT-PCR and western blotting analysis revealed that CsFABP mRNA and protein were differentially expressed throughout the developmental cycle stages of the parasite, which occur in the definitive host (metacercariae, adult worms, and eggs). In addition, immunolocalization assay showed that CsFABP was localized on the vitelline gland, tegument, intestine, seminal vesicle, eggs in uterus, ovary, and testicle of C. sinensis adult worm, as well as on the vitelline gland of metacercaria. Intriguingly, the surface tissue of the bile duct where C. sinensis resided in the infected Sprague-Dawley rat was also strongly labeled, implying that CsFABP may possibly mediate direct interactions with host cells as a component of excretory/secretory products.Molecular and Cellular Biochemistry 12/2011; 363(1-2):367-76. · 2.06 Impact Factor -
Article: Down-regulation of BMI-1 cooperates with artemisinin on growth inhibition of nasopharyngeal carcinoma cells.
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ABSTRACT: Artemisinin and its derivatives are well known antimalaria drugs, particularly useful for the treatment of infection of Plasmodium falciparum malaria parasites resistant to traditional antimalarial pharmaceuticals. Artemisinin has inhibitory effects on cancer cell growth and anti-angiogenetic activity, including many drug- and radiation-resistant cancer cell lines. Moloney murine leukemia virus insertion site 1 (BMI-1) has been shown to regulate proliferation by inhibiting p16(ink4a) transcription. It is well known that BMI-1 over-expression was found in nasopharyngeal carcinoma cell lines and correlated with advanced invasive stage of the tumor progression and poor prognosis. In the present investigation, we analyzed the inhibitory effects of artemisinin on proliferation of nasopharyngeal carcinoma cell lines (CNE-1 and CNE-2, well-differentiated cells, and poorly differentiated cells). We demonstrated that artemisinin induced G1 cell cycle arrest in CNE-1 and CNE-2 cells. Artemisinin inhibited BMI-1 both in protein and transcript levels. BMI-1 knockdown made the cells more sensitive to artemisinin with an increase in G1 phase, but over-expression of BMI-1 partially reversed the artemisinin-induced G1 cell cycle arrest. Depletion of BMI-1 was able to intensifying the increment of p16 and the reduction of CDK4 induced by artemisinin. In addition, over-expression of BMI-1 was capable of attenuating the increasing p16 and decreasing CDK4 in cells treated with artemisinin. Taking together, the BMI1-p16/CDK4 axis was involved in the artemisinin-driven G1 arrest in nasopharyngeal carcinoma cells, and these results indicated that a potential treatment that the combination of artemisinin and BMI-1 downregulation could enhance the growth inhibitory affects on nasopharyngeal carcinoma cells.Journal of Cellular Biochemistry 03/2011; 112(7):1938-48. · 2.87 Impact Factor -
Article: Clonorchis sinensis enolase: identification and biochemical characterization of a glycolytic enzyme from excretory/secretory products.
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ABSTRACT: Enolase plays a key role in energy metabolism and development of most organisms. We isolated a gene encoding enolase from Clonorchis sinensis (C. sinensis) adult cDNA library and expressed the recombinant protein in Escherichia coli. C. sinensis enolase (Csenolase) was identified as both an excretory/secretory product and a tegumental component of C. sinensis by western blot analysis. The transcriptional level of Csenolase was examined at adult worm, metacercaria, cercaria and egg of C. sinensis, and results showed that Csenolase is transcribed at the four life stages of C. sinensis while showing a significant higher expression level at the stage of adult worm. Immunohistochemical localization indicated that Csenolase was specifically deposited on the tegument of adult worm and cyst wall of metacercaria. Ligand blot assay revealed a specific characteristic of dose-dependent plasminogen-binding activity of Csenolase and kinetic parameters were explored using 2-phospho-D-glycerate (2-PGA) as the primary substrate by monitoring the conversion of nicotinamide-adenine dinucleotide (NADH) into nicotinamide adenine dinucleotide (NAD). In addition, Csenolase exhibited active enzyme activity in catalytic reactions while the anti-Csenolase serum inhibited the enzyme activity. In vitro incubation experiments revealed that Csenolase might play key roles in the growth of the parasites. In conclusion, Csenolase is an important glycolytic enzyme required for the development of C. sinensis, and may be a potential vaccine candidate and drug target against C. sinensis infection.Molecular and Biochemical Parasitology 03/2011; 177(2):135-42. · 2.55 Impact Factor -
Article: Molecular cloning, characterization, and immunolocalization of two lactate dehydrogenase homologous genes from Taenia solium.
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ABSTRACT: Two novel genes encoding lactate dehydrogenase A (LDHA) and B (LDHB) homologues, respectively, were identified from the cDNA libraries of adult Taenia solium (T. solium). The two deduced amino acid sequences both show more than 50% identity to the homologues for Danio rerio, Xenopus laevis, Schistosoma japonicum, Sus scrofa, Homo sapiens, et al. The identity of the amino acid sequence between TsLDHA and TsLDHB is 57.4%, and that of the nucleotide sequence is 61.5%. Recombinant TsLDHA homologue (rTsLDHA) and TsLDHB homologue (rTsLDHB) were expressed in Escherichia coli BL21/DE3 and purified. Though there were some differences in the sequence, the two LDH isozyme homologues show similarity in the conserved LDH domain, topological structure, primary immunological traits, localization on the tegument of T. solium adult, and partial physicochemical properties. The linear B-cell epitope analysis of TsLDHA and TsLDHB discovered a TsLDHA specific epitope. The purified rTsLDHA and rTsLDHB could be recognized by rat immuno-sera, serum from swine, or a patient infected with T. solium, respectively, but Western blot analysis showed cross-reactions, not only between these two LDH members but also with other common human tapeworms or helminths. The results suggested that the two LDH homologues are similar in the characteristics of LDH family, and they are not specific antigens for immunodiagnosis.Parasitology Research 02/2011; 109(3):567-74. · 2.15 Impact Factor -
Article: Molecular characterization and expression of the MYND-ZF gene from Clonorchis sinensis.
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ABSTRACT: The MYND-type zinc finger protein (MYND-ZF) is a large group of proteins containing the MYND domain which play an important role in protein-protein interactions. A cDNA clone encoding a novel MYND-ZF was isolated and identified from a Clonorchis sinensis (C. sinensis) adult cDNA library. The open reading frame of this novel cDNA sequence contains 1,440 base pairs with a putative protein of 479 amino acids showing a high homology with the MYND-ZF identified from other species. Recombinant CsMYND-ZF was expressed and purified from Escherichia coli BL21 (DE3). CsMYND-ZF transcripts were detected in the cDNA of adult worms and metacercariae but not in eggs of C. sinensis. Immunohistochemistry results revealed that CsMYND-ZF was deposited at the tegument of adult worms and metacercariae C. sinensis using anti-recombinant CsMYND-ZF serum. These findings may contribute to the development of a reliable diagnostic method.Parasitology Research 10/2010; 107(5):1249-55. · 2.15 Impact Factor -
Article: Th1 immunity is not required for the effect of lipopolysaccharide exposure on modifying asthmatic responses of mice before sensitization.
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ABSTRACT: Disequilibrium of Th1/Th2 is known as an important cause of allergic asthma with a biased Th2 type response. It has been shown that lipopolysaccharide (LPS) administration during post-sensitization modified the inflammation of asthma via upregulating the Th1 response that decrease the Th2 immunity. We would like to know if, during pre-sensitization, the elevated Th1 response is necessary for LPS exposure to modify the asthmatic response. During pre- or post-sensitization, 40 microg LPS were intraperitoneal injected (i.p.) to asthmatic mice sensitized and challenged by Dermatophagoides farinae (D. farinea). Inflammation was assessed by examining bronchoalveolar lavage fluid (BALF) for the number and identity of cells and by cytokine titers measured by ELISA. Semi-quantified RT-PCR was used to evaluate the level of Toll-like receptor 4 (TLR4) mRNA in dendritic cells (DCs) from bone marrow (BMDCs). These investigations demonstrated that LPS exposure during pre-sensitization inhibited the Th2 cytokine and inflammatory infiltration, the same as with LPS exposure during post-sensitization in allergic asthma mice. Contrary to post-sensitization LPS exposure, the Th1 cytokines were not upregulated by pre-sensitization with LPS. Finally, the study failed to show any significant difference between TLR4 mRNA expressed in BMDCs with the two times of LPS exposure. Our data suggest that elevated Th1 immunity is not required for the modification of the Th2 response induced by LPS exposure during pre-sensitization in asthmatic mice and that pre-sensitization differs from post-sensitization. Immune modulation with treatment is independent of TLR4 expression in BMDCs. This study implicates a potential way to protect from allergic disease and an inflammatory response.Chinese medical journal 04/2010; 123(8):1047-51. · 0.86 Impact Factor -
Article: Expression and immune response analysis of Schistosoma japonicum VAL-1, a homologue of vespid venom allergens.
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ABSTRACT: Many parasites such as trematodes and nematodes have been found to express members of a gene family variously termed as venom allergen-like protein (VAL) or sperm-coating protein (SCP)-like protein. The molecular functions of these proteins remain unclear. We isolated the corresponding gene from Schistosoma japonicum, which we designated as Sj-VAL-1. The cDNA of Sj-VAL-1 contains an open reading frame encoding 221 amino acids, the first 25 residues being a putative secretion signal. RT-PCR analysis confirmed that Sj-VAL-1 was transcribed mainly in cercariae and eggs stages. Western blot analysis indicated that Sj-VAL-1 protein was an egg excretory-secretory products (ES products). Immunofluorescence showed it was secreted by eggs, head gland, and penetration glands of cercariae. In S. japonicum-infected mice, Sj-VAL-1-specific antibody significantly increased 6 weeks after infection and a higher level of IgG1 antibody contrast to IgG2a antibody indicated that a polarized Th2 immune response could be induced by Sj-VAL-1. These findings suggest that Sj-VAL-1 must play a role in the interaction between parasite and host. Its role as a potential modulator of immune function or as a pathogenic factor of granuloma formation in schistosomiasis needs further study.Parasitology Research 03/2010; 106(6):1413-8. · 2.15 Impact Factor -
Article: Stage and tissue specific differences in SjBMI1, a Polycomb protein in Schistosoma japonicum.
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ABSTRACT: Polycomb group protein BMI1, plays a central role in the stem cell pluripotency and development in metazoans. A gene encoding BMI1 homologue in the Schistosoma japonicum (SjBMI1) was cloned and identified. The deduced amino acid sequence shows high identity to the homologues from Schistosoma mansoni and Homo sapiens. Quantitative real time polymerase chain reaction (RT-PCR) and Western blot analysis revealed that the SjBMI1 is highly expressed in adult worms and eggs, not in cercariae. By immunofluorescent studies, SjBMI1 was localized to testes, ovaries of mixed sex infected adult worms, but not of single sex infected adult worms. The study reveals the SjBMI1 expression profile in developmental stages and localization characteristic and provides a clue that it may be associated with reproductive development of S. japonicum.Parasitology Research 02/2010; 106(3):677-82. · 2.15 Impact Factor -
Article: Molecular cloning and characterization of a novel serpin gene of Clonorchis sinensis, highly expressed in the stage of metacercaria.
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ABSTRACT: The serpins are a superfamily of proteins (350-500 amino acids in size) that fold into a conserved structure. From about 3,475 unigenes of Clonorchis sinensis metacercaria, a novel gene-encoding serpin was identified and characterized. The opening reading frame is 1,149 bp encoding 382 amino acids. The deduced amino acid sequence shows high identity to previously reported serpins from C. sinensis and other helminthic parasites. A typical serpin signature was found by motif search. The recombinant C. sinensis serpin protein (rCsproSERPIN) was produced and purified. Semiquantitative analysis revealed that the transcripts of this serpin gene in metacercaria were much higher than that in adult worms and that the corresponding band of serpin protein in the crude soluble antigen of metacercaria probed by rat anti-CsproSERPIN serum was also much clearer compared with that of adult, suggesting that it plays an important role in the stage of C. sinensis metacercaria. Although we are not much clear about the detailed function of this serpin protein, the study that proteinase initiates metacercaria excystment gives a clue that it may participate in the encystment of cercaria.Parasitology Research 10/2009; 106(1):221-5. · 2.15 Impact Factor -
Article: [Study of Scutellaria baicalensis and Baicalin against antimicrobial susceptibility of Helicobacter pylori strains in vitro].
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ABSTRACT: To compare the antimicrobial activities of Scutellaria baicalensis and Baicalin against Helicobacter pylori (H. pylori) in vitro. The crude alcohol extraction of Scutellaria baicalensis was obtained by successive extractions with ethanol. Baicalin was extracted by using organic extraction methods and the purity was analyzed by high-performance liquid chromatography (HPLC). The crude alcohol extraction of Scutellaria baicalensis and Baicalin were used in broth dilution assays to test for antibacterial properties. The content of Baicalin was 5.01 g from 100 g Scutellaria baicalensis. The purity of Baicalin was 96.8%. The crude alcohol extraction of Scutellaria baicalensis and Baicalin were tested for their ability to inhibit H. pylori in vitro by using broth dilution assays. The MIC50 and MIC90 of Baicalin against ten strains of H. pylori were 1.04 and 1.30 mg/ml respectively. The MIC50 and MIC90 of the crude product against ten strains of H. pylori were 2.60 and 3.26 mg/ml respectively. The Baicalin and Scutellaria baicalensis are bactericidal against H. pylori. The antimicrobial activity of Baicalin is greater than that of Scutellaria baicalensis.Zhong yao cai = Zhongyaocai = Journal of Chinese medicinal materials 06/2008; 31(5):707-10. -
Article: [Detonation temperature measurement of epoxypropane using instantaneous spectrum method].
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ABSTRACT: After solving the problems of synchronization of the measuring system and the avoidance of false trigger signal, the instantaneous emission spectrum of epoxypropane with an exposure time of 2 micros and a resolution of 0.2 nm was acquired from a side window of a shock tube at the very moment when the epoxypropane transformed from deflagration to detonation. The measuring system consists of an advanced intensified charge-coupled-device spectroscopic detector, a digital delay generator DG535, an explosion shock tube and optical fibers. The DDT process was monitored by pressure transducers. After correcting the intensity of the spectrum obtained, the background curve of the heat radiation intensity of the detonation was given immediately. The detonation temperature of 2 416 K for epoxypropane was derived from fitting the curve with Planck blackbody formula by least squares principle. The detonation temperature of epoxypropane can provide an experimental datum for analyzing the microscopic mechanism of DDT process.Guang pu xue yu guang pu fen xi = Guang pu 04/2008; 28(3):490-3. · 0.84 Impact Factor -
Article: [The effect of rural exposure on allergic asthma in Anhui province].
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ABSTRACT: To establish the evidence of exposure to rural areas would reduce the risk of atopic asthma and sensitization. A cross-sectional survey was carried out in 2986 school-age children and their parents completed standardized questionnaires on atopic asthma and sensitization, wheezing. A radioallergosorbent technique-fluorescence enzyme immunoassay (RAST-FEIA) was used to measure the level of specific IgE in serum. The risks of atopic and non-atopic asthma (OR = 0.45, 95% CI:0.13-0.96 and OR=0.41, 95% CI:0.15-0.95), atopic sensitization. and wheezing (OR= 0.32, 95% CI:0.11-0.62; OR =0.44, 95% CI:0.13-0.91) were lower in subjects living in village area compared with those living in towns. The risks of atopic asthma and sensitization were lower in subjects exposed to stables in first year (OR=0.23, 95% CI:0.04-0.91 and OR =0.32, 95% CI:0.17-0.78) and were lowest in those exposed continually until the age of 6 (OR = 0.21, 95% CI:0.03-0.87 and OR = 0.31, 95% CI:0.15-0.78) compared with those non-exposed in the first 6 years. Exposure to rural environment might have a protective effect on children against atopic asthma and sensitization while continual exposure could strengthen the effects.Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 04/2008; 29(3):245-7. -
Article: Shock-induced fast reactions of zinc nanoparticles and RDX
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ABSTRACT: Fast reactions of zinc nanoparticles and RDX were investigated in normal incident shock waves. The emergence time and emission spectra intensity of partial products such as NO2, H, C2, O, CO, CH2O, CO2, H2O and ZnO were observed by a TDS5054 oscilloscope. The results indicate that NO2 appears first in each experiment, which is in agreement with the theoretical results. The addition of zinc nanoparticles to RDX can not only shorten the ignition delay time by 20% but also double the shockwave diffusion velocity to 2180 ± 50 m s−1 and triple the temperature to 2020 ± 60 K. The emergence time of products shortens by around 10–40% and the emission spectra intensity of H2O and CH2O rises by about three times and one times, respectively. CO2, H2O and O2 in various concentrations were introduced into the zinc–RDX reaction, respectively, which indicate that O2 made the ignition delay time shorten by over 30%, the effect of H2O was not prominent while CO2 made the ignition delay time lag by around 30%. The results indicate that the Zn–O2 reaction mainly occurs in O2, CO2 and H2O.Journal of Physics D Applied Physics 01/2008; 41(4):045501. · 2.54 Impact Factor -
Article: [Spectrum studies of ignition characteristic in quick reaction of benzene].
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ABSTRACT: A new optical spectroscopy system consisting of a monochromator, photomultiplier tubes (PMT), piezoelectric pressure sensor and digital phosphor oscilloscope was established to study spectrum and ignition delay time of benzene in quick reaction in a high temperature shock tube. A new method of determining ignition delay time of energetic materials behind incident shock wave is proposed. Several important products, such as H, C2 and CH, were determined in sequence of emergence time. The reaction mechanism of formation of carbon was introduced when benzene was driven under shock compression. The results indicate that in spite of the variety of Mach number, atom H always emerged first, indicating that the pyrolysis of benzene started with C-H bond instead of C-C bond. The results show that applying spectrum techniques can preferably study the ignition characteristic of benzene in quick reaction. Measuring ignition delay time by means of a prior emerged intermediate product (atom H) is more accurate than that with white color technique widely used home and abroad, and furthermore, can obviously reduce the times of experiment.Guang pu xue yu guang pu fen xi = Guang pu 01/2008; 27(12):2396-8. · 0.84 Impact Factor -
Article: [Study on the relations between concentration of endotoxin in dwelling and atopic asthma in school-age children].
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ABSTRACT: To explore the effect of endotoxin concentration in dwellings on the prevalence of atopic asthma in children. Standardized questionnaires of asthma were distributed to the parents of 2986 school children aged between 8 and 12 years and endotoxin content in children's mattress was measured by a kinetic limulus assay. A radioallergosorbent technique--fluorescence enzyme immunoassay (RAST-FEIA) was used to measure the level of specific IgE in serum. Complete data was available for 904 children with males more than females. There were both negative associations seen between endotoxin levels and both atopic asthma (OR = 0.48, 95% CI: 0.32-0.72, P < 0.05) and atopic sensitization (OR = 0.65, 95% CI: 0.49-0.94, P < 0.05) but not with non-atopic asthma and wheeze. Comparing with normal people, patients with atopic sensitization, atopic wheeze and atopic asthma had a higher levels of endotoxin (M-W U: 15 138.0, P < 0.01, M-W U: 4858.0, P < 0.01, M-W U: 4041.0, P < 0.01). Exposure to endotoxin in early lives of children might have a protective effect on atopic asthma and sensitization.Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 04/2007; 28(4):354-7. -
Article: [Using instantaneous spectra to determine dominant species in the DDT process of epoxypropane].
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ABSTRACT: After solving problems of weak light detection, the calibration of the spectral sensitivity of the measuring system, and the synchronization of the measuring system, instantaneous emission spectra of epoxypropane in the process of deflagration to detonation transition (DDT) with the exposure time of 2-8 micros and the resolution of 0. 2 nm were acquired from six different side windows of an explosion shock tube. Using the corrected spectral data, curves of the optical radiant intensity of main reaction products versus the DDT distance from the ignition point were obtained. These curves provided information about the evolution of the reaction and the products during the DDT process. Results indicate that the chemical reaction rate of the gaseous fuel and the corresponding concentrations of intermediate products increased gradually at the deflagration stage, but at the moment of deflagration to detonation transition, the reaction rate increased rapidly and the concentrations! of products increased sharply. Among these main products, concentration increments of molecule CO, and radicals CHO and OH were greater than other products, which means that CO, CHO and OH are the dominant species that affect the DDT process greatly.Guang pu xue yu guang pu fen xi = Guang pu 10/2006; 26(9):1569-72. · 0.84 Impact Factor
Top co-authors
Top Journals
Institutions
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2011
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Guangzhou First People's Hospital
Guangzhou, Guangdong Sheng, China
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2009–2010
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Sun Yat-Sen University
Guangzhou, Guangdong Sheng, China
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2007
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Anhui Science and Technology University
Bengbu, Anhui Sheng, China
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