傣药“雅解沙把”抗变态反应的实验研究

目的:研究傣药"雅解沙把"对抗变态反应的作用。方法:采用小鼠异种被动皮肤过敏反应(PCA)、组胺所致豚鼠瘙痒法和DNFB所致小鼠耳廓皮肤迟发型超敏反应(DTH)实验,探讨"雅解沙把"的抗变态反应作用。结果:"雅解沙把"能显著抑制小鼠异种被动皮肤过敏反应,提高豚鼠对磷酸组织胺的致痒阈,并能抑制DNFB诱导的DTH。结论:"雅解沙把"具有抗Ⅰ、Ⅳ型变态反应作用。

Effects of Oleanolic Acid on the Immune Complex Allergic Reaction and Inflammation

When oleanolic acid (OA) was administered ig before and after sensitization on d 1 to d 5 and d 11 to d 17,it had no apparent effect on Arthus reaction.When it was administered at 48,24 and 1 h before challenge,however,Arthus reaction was significantly inhibited.OA showed markedly suppressive effects on reversible passive Arthus reaction and leukocyte migratory response.It could significantly stabilize erythrocyte membrane,inhibit the swelling of the rat's hind paw induced by in- jecting mycostatin,reduce the acid phosphatase content in the inflammatory exudate,suppress the syn- thesis or release of PGE,histamine,LTB4 and kinin,and the phlogistic action of PGE_2,histamine,5- HT and kinin.In addition,it could decrease the content of malonyldialdehyde (MDA) in hepatic tissue of alcohol-intoxicated mice,and increase the activity of catalase (CAT) in hepatic tissue of mice.OA had no apparent effect on the activity of super-oxide dismutase (SOD) in rat serum,on the content of immune complex in serum of rat with Arthus reaction,on the phagocytosis of monocytc-macrophage system,on the clearance of enzyme-containing immune complex by macrophage,or on the activity of total complement.

Establishment of BALB/c Mice Model for Food Allergy to Chinese Lobsters

[Objective] This study aimed to establish Balb/c mice model for food allergy caused by Chinese lobsters through using intraperitoneal injection for sensitization and explore methods for in vitro identification and evaluation of food allergy caused by Chinese lobsters. [Method] The 40 male Bal/c mice were divided into ovalbumin（OVA） positive control group, Coca＇s solution negative control group, blank control group and model group. Balb/c mice model was established by intraperitoneally injection of immunized Balb/c mice with OVA or Chinese lobster crude protein with aluminum hydroxide adjuvant. IgE and histamine levels in serum after the second challenge were determined by ELISA method, and the specific IgE antibody titer was determined by passive cutaneous anaphylaxis test（PCA）; additionally, spleen index and histological changes in the small intestine, as well as food allergy symptoms after challenge were also calculated or observed. [Results] After the last challenge, IgE content was（236.75 ±73.39） μg/L in the Chinese lobster crude protein group, revealing no difference with that in the OVA group, but significantly higher than that in either the Coca＇s solution group or the blank control group（P 0.01）;histamine content in serum in the Chinese lobster crude protein group was（406.55±232.79）, significantly higher than that in the blank control group（P0.01）. In the passive cutaneous anaphylaxis test, IgE antibody titer reached 1/16 after the last challenge in the Chinese lobster crude protein group. Spleen index in both Chinese lobster crude protein group and OVA group was significantly greater than that in either the Coca＇s solution group or the blank control group（P0.01）. What＇s more, infiltration of inflammatory cells like lymphocytes and eosnophils at the lamina propria of intestinal mucosa was also observed both Chinese lobster crude protein group and OVA group. [Conclusion] This study established Balb/c mice model for food allergy caused by Chinese lobsters; serum IgE and ELISA assay and specific IgE antibody titer in PCA test can be used for the in vitro identification and evaluation of food allergies caused by Chinese lobsters.

Studies on the relationship between the point mutation of ras oncogenes and the prognosis of patients with gastric cancer

AIM To study the relationship between the point mutation of ras oncogenes and the prognosis of patients with gastric cancer.

HOUSE DUST MITE ALLERGEN (Derp1 AND Blot5) LEVELS IN ASTHMATICS' HOME IN HONGKONG

To measure Derp1 and Blot5 allergen levels in asthmatics’ homes in Hongkong. Methods Seventy houses were enrolled for a mite indoor environment study. Dust samples were obtained from two sites of each patients’ house: bed and floor. Derp1 and Blot5 levels were quantified by a two-site monoclonal antibody-based ELISA technique. Results The levels of Derp1 allergens found in bed (geometric mean (GM) 3.43 μg/g of dust; 95%CI, 1.89-4.96 μg/g) and on the floor (GM 1.12 μg/g of dust; 95%CI, 0.71-1.53 μg/g) indicated significant differences (P = 0.005). However, the levels of Blot5 allergens found in bed (GM 19.00 μg/g of dust; 95%CI, 0.89-38.90 μg/g) and on the floor (GM 6.14 μg/g of dust; 95%CI, 0.40-11.90 μg/g) showed no statistically significant difference. In addition, in regards to the exposure index for Derp1 and Blot5 allergens found in bed and on the floor, 17.6% in bed and 8.6% on the floor had levels of Blot5 ≥ 10 μg/g of dust, higher than those obtained for Derp1 (7.2% and 0% in bed and on the floor respectively, P < 0.05); higher percentages in bed and on the floor (25.0% and 35.7%) were observed for levels of Blot5 = 0 μg/g of dust as compared with Derp1 in bed and on the floor (4.3% and 14.5% respectively, P < 0.05). Conclusions Derp1 and Blot5 are the major allergens found in this regional study, Blot5 is a more potent allergen in Hongkong, probably reflecting the high level of exposure to Blomia tropicalis (Bt). Bt and Dermatophagoides pteronyssinus(Dp) allergens should be included for precise diagnosis and effective immuno-therapeutic treatment of mite allergy in Hong-kong.

Airborne Pollen Grains Of Afyon, Turkey

The airborne pollen grains of Afyon have been studied for a two_year period (1999-2000) with a Durham sampler. A total of 14 367 pollen grains belonging to 40 taxa have been identified and recorded with some unidentified ones. Of them, 6 732 were identified in 1999 and 7 635 in 2000. Of the total pollen grains, 69.67% were arboreal, 26.64% non_arboreal and 3.68 % unidentified. The majority of the investigated pollen grains were from Pinus, Gramineae, Cupressaceae, Platanus , Chenopodiaceae/Amaranthaceae, Quercus, Ailanthus, Moraceae, Juglans , Salix, Cedrus and Rosaceae. The highest level of pollen grains was in May.

Fabrication of wavy γ-TiAl based sheet with foil metallurgy

A 0.7 mm-thick wavy γ-TiAl sheet with fully lamellar microstructure was fabricated by hot pressing Ti/Al alternate foils with heat treatment of 640 °C, 15 h＋850 °C, 35 h＋1350 °C, 2 h. The intermetallic compounds formed during heat treatments were identified by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. TiAl3 was the only observed phase at the Ti/Al interface when Al foils were not consumed. After being annealed at 850 °C for 35 h, the microstructure was composed of α-Ti, α2-Ti3Al, γ-TiAl and TiAl2. A fully lamellar microstructure formed after annealing at 1350 °C. Most of the angles between the lamellar interface and the sheet plane are below 30°. Using thinner starting foils is favorable to produce sheets with fine microstructure.

Concentrations of gastric mucosal cytokines in children with food allergy and Helicobacterpylori infection

AIM： To measure the concentrations of chosen cytokines in the antrum mucosa depending on the kind of harmful pathogenic factors and to compare the concentrations with the values of controls without allergy and coexisting Helicobacter pylori （H pylori） infection. METHODS： The patients （97 children） were divided into three groups according to the data obtained from the case history, to the main cause of the disease and to the dominant clinical symptoms. Group Ⅰ： children with food allergy （Fa）; group Ⅱ： children infected with H pylori; group Ⅲ （control group）： children with functional disorders of the alimentary tract （without Fa and Hp infection）. H pylori infection was determined by the presence of anti-Hp antibodies in serum （ELISA method） and urease test performed during endoscopic examination. Cytokine concentration in homogenates of gastric mucosa was detected by ELISA method. RESULTS： The IL-2 concentration in gastric mucosa bioptates was the highest in children with Hp infection （116.5±179.5 pg/mg of the protein） and Fa and Hp infection （98.1±101.0 pg/mg）, while decreased in children with Fa （44.8±50.3 pg/mg） and controls （45.7±23.5 pg/mg）. The lowest mean concentration of IFN-y was observed in children with Hp infection （18.9±16.4 pg/mg）, with Fa and Hp infection （25.5±27.7 pg/mg）, with Fa （40.6±39.7 pg/mg） and controls （49.9±33.4 pg/mg）. The highest IL-4 concentrations were observed in children with Hp infection （35.3±52.8 pg/mg） and in children with Fa and Hp infection （37.2±51.7 pg/mg）, while lower IL-4 concentration （23.64-35.8 pg/mg） was found in children with Fa compared to the controls （22.7±13.8 pg/mg）. The analysis of IL-4 concentrations in children with Hp infection regarding the intensity of gastritis showed the highest value （62.2±61.2 pg/mg） in mild and moderate gastritis. The concentrations of IL-5 in the gastric mucosa of children with or without Fa did not differ significantly and were comparable to the control group. The highest mean IL-8 value was observed in Hp-infected children with or without Fa. The highest concentration of mucosal IL-10 was detected in children with Hp infection （79.3±41.2 pg/mg） and decreased in children with Fa and Hp infection （50.1±18.8 pg/mg） and in children with Fa （39.9±35.5 pg/mg）. The intensity and activity of the inflammation did not affect IL-10 concentrations in the gastric mucosa. In children with Hp infection, TNF-α concentration was the highest （45.9±49.3 pg/mg） and in children with Fa and Hp infection was low （45.3±32.6 pg/mg）, whereas decreased in children with Fa （21.7±34.2 pg/mg） and in controls （31.6±14.5 pg/mg）. CONCLUSION： The morphological changes of the gastric mucosa in children with Hp infection are comparable to those in children with Fa and coexisting Hp infection. Cytokine concentration in children with Fa and Hp infection is significantly different in IFN-7, IL-2, IL-8, and TNF-α.

EFFECTS OF SDS,PBS SOLUTIONS UPON FLUORESCENCE VALUES OF DERMATOPHAGOIDES PTERRONYSSINUS RADIOALLERGOSORBENT TEST INHIBITION

Objective To explore the effects of SDS, PBS re-dissolvent solutions on fluorescence values of radioallergosorbent test (RAST) inhibition. Methods Dermatophagoides pterronyssinus allergen immunoCAP and UniCAP 100 System were used. The Sera Pool consisted of 20 Dermatophagoides pterronyssinus allergic patients sera, their specific IgE fluorescence values were between 12 505 and 24 776. Results Fluorescence value percentages decreased: 62.9%, 54.1%, 43.5%, 6.7%, 3.7%, 2.6%, 2.2%, and 1.4% respectively, when SDS concentrations were at 2%, 1%, 0.5%, 0.25%, 0.1%, 0.05%, 0.025%, and 0.01%. Fluorescence values decreased more than 5% with SDS concentrations equal to 0.25% or higher. PBS in 0.1 and 0.01 mol/L concentrations decreased fluorescence values 2.9% and 0.9% respectively. Conclusions SDS is a commonly used surfactants in allergen extract and re-dissolvent prepared allergen precipitation for RAST inhibition. Thus effects of surfactants (e.g. SDS) upon the RAST inhibition tests must be considered when they were used as re-dissolvent agents to improve protein resolution in RAST inhibition.

Study on drilling mechanism and optimization of percussion-extruding DTH hammer bit

The authors tested the percussion-extruding Down-the-hole(DTH)hammer bit with five different structures and mainly analyzed the drilling mechanism between conical bit and stepped bit.In addition,aiming at "the pile effect" in combination with the advantage of stepped bit,we design a new cam spinning bit and test it outdoors.The result shows that using cam spinning bit can solve the problem of "the pile effect",which can also obtain higher drilling efficiency than using conical bit in high confining pressure strata.It is characterized by novel structure and high drilling speed as well as good guiding,and it is significant for improving efficiency in percussion-extruding drilling technique.

POLYMER-SUPPORTED SINGLE AND MIXED AMMONIUM AND PHOSPHONIUM SALTS AS CATALYSTS FOR PHASE-TRANSFER REACTIONS

In this study was to investigate, by phase-transfer catalysis, the activity of single and mixed ammonium and phosphonium salts grafted on a 揼el-type?styrene-7% divinylbenzene copolymer in the oxidation of benzyl alcohol with hydrogen peroxide. A wide variety of catalysts with different quaternary groups and different quaternary chain length substituents were examined. The activity of single 搊nium?salts increases as a consequence of the association of ammonium and phosphonium salts grafted on the same polymeric support. The activity of polymer-supported ammonium and phosphonium salts increases with the number of carbon atoms contained in the alkyl radicals of the onium and of the functionalization degree with phosphonium groups.

Mixed signals in trends of variance in high-elevation tree ring chronologies

Increases in climate variability, including extremes, may be expected with anthropogenic climate change, but some evidence is contrary. The issue is important because the consequences of variability can be critical for ecosystems. It has long been known and often rehearsed that ecological consequences of increased variability may be greater than those that result from expected changes in mean temperature and precipitation. Tree rings have been useful indicators of ecological response to climate change and used as proxies for climate variability;work in the Rocky Mountains, USA, has been particularly informative. Chronologies from two high elevation species ranging over 2500 km were analyzed for changes in variance through time. These spatially extensive and disaggregated tree ring records do not show a consistent pattern of change in variance over the past 500 or 100 years; heteroscedasticity has recently been greater. A lack of consistent response in growth over a period encompassing changes in mean climate indicates that mountain environments, with inconsistent trends in temperature and precipitation,may be too complex to act as sentinels.

TLR4 -2242 T→C variant increases transcriptional activity of its promoter

Objective:To investigate the effects of -2242,-1892 and -1837 single nucleotide polymorphisms(SNPs) on toll-like receptor 4(TLR4) promoter activity.Methods:Polymerase chain reaction(PCR) and site direct mutation technology were used to construct TLR4 basic promoter and -2242C,-1892A and -1837G mutate promoter plasmids.Dual-Luciferase Reporter assay system was used to detect the activity of constructed promoter following human embryonic kidney(HEK) 293 cells were transiently cotransfected with the constructed plasmids and the control plasmid pRL-CMV.Results:In HEK293 cells,the activity of -2242C mutate promoter was higher than -2242T promoter,and there was no significant difference when both -1892A and -1837G mutate promoter compared with -1892G and -1837A promoter,respectively.Conclusion:It is implied that -2242T→C base variation can enhance the activity of TLR4 promoter,while -1892 and -1837 SNPs have no effect on TLR4 promoter activity.

RNA interference against interleukin-5 attenuates airway inflammation and hyperresponsiveness in an asthma model

Interleukin-5 (IL-5) accompanies the development of airway inflammation and hyperresponsiveness through the activation of eosinophils. Therefore, interference of IL-5 expression in lung tissue seems to be an accepted approach in asthma therapy. In this study, we designed a small interfering RNA (siRNA) to inhibit the expression of IL-5. The siRNAs against IL-5 were constructed in a lentivirus expressing system, and 1.5×106 IFU (inclusion-forming unit) lentiviruses were administered intratracheally to ovalbumin (OVA)-sensitized murine asthmatic models. Our results show that lentivirus-delivered siRNA against IL-5 efficiently inhibited the IL-5 messenger ribonucleic acid (mRNA) expression and significantly attenuated the inflammation in lung tissue. Significant decrease of eosinophils and inflammatory cells were found in peripheral blood, bronchoalveolar lavage fluid (BALF), and lung tissue. In addition, significant inhibition of airway hyperresponsiveness (AHR) was found in the mice treated with siRNA against IL-5. These observations demonstrate that siRNA delivered by means of the lentivirus system is possibly an efficacious therapeutic approach for asthma.

A facile hydrothermal preparation and photoluminescence study of ZnO micro/nanostructures on Zn foils

ZnO micro/nanostructures with various morphologies were grown via hydrothermal etching of Zn foil.Controlling the reaction temperature and time,rod-like,pencil-like,tube-like and flowerlike ZnO micro/nanostructures could be prepared directly on the Zn foil surface at temperatures 100-180℃ with excellent reproducibility.X-ray diffraction patterns indicated that these ZnO micro/nanostructures were hexagonal.Possible mechanisms for the variation of morphology are discussed.Moreover,photoluminescence spectra of the as-grown samples revealed that all of them consist of UV emission band at around 392 nm.

Mechanistic study and kinetic properties of the CF_3CHO+Cl reaction

Theoretical investigations have been carried out on the mechanism and kinetics for the reaction of CF 3 CHO + Cl using duallevel direct dynamics method. The potential energy surface information was obtained at the MCQCISD/3//MP2/cc-pVDZ level and the kinetic calculations were done using variational transition state theory with interpolated single-point energy (VTST-ISPE) approach. The calculated results show that the reaction proceeds primarily via the H-abstraction channel, while the Cl-addition channel is unfavorable due to the higher barriers. The improved canonical variational transition-state theory (ICVT) with the small-curvature tunneling correction (SCT) was used to calculate the rate constants. The theoretical rate constants at room temperature are in general agreement with the experimental values. A three-parameter rate constant expression was fitted over a wide temperature range of 200-2000 K.

The roles of heterogeneous chemical processes in the formation of an air pollution complex and gray haze

Urban and regional air pollutions are characterized by high concentrations of secondary pollutants such as photo-oxidants （mainly ozone） and fine particulate matter, which are formed through chemical reactions of the primary pollutants emitted from various sources. The accumulation of these pollutants under stagnant meteorological conditions results in the formation of gray haze, reducing visibility and causing major impacts on human health and climate. In an air pollution complex, the co- existence of high concentrations of primary and secondary gaseous and particulate pollutants provides a large amount of reac- tants for heterogeneous reactions on the surface of fine particles; these reactions change the oxidizing capacity of the atmos- phere, as well as chemical compositions along with the physicochemical and optical properties of particulate matter, thereby accelerating formation of the air pollution complex and gray haze. Using in situ technologies, such as diffuse reflectance infra- red Fourier-transform spectroscopy and single-particle Raman spectroscopy, we systematically investigated the reaction kinet- ics and mechanisms of gaseous pollutants （i.e., NO2, SO2, 03, and formaldehyde） on the surfaces of the major components of atmospheric particles such as CaCO3, kaolinite, montmorillonite, NaC1, sea salt, A1203, and Tit2. We found that the main re- action products were sulfate, nitrate, or formate, which can change the hygroscopicity and light extinction parameters of those particles significantly. By analyzing the reaction kinetics of these heterogeneous reactions, we identified synergetic mechanisms of the three ternary reaction systems, ,i.e., NOE-particles-H2O, SO2-particles-O3, and organics/SO2-particles-UV illumination. These synergetic mechanisms can provide experimental and theoretical bases for understanding the feedback mechanisms and nonlinear processes in the formation of an air pollution complex and gray haze.

Kinetic calculation for the reaction of H with Si_2H_6 using the variational transition state theory

The reaction of disilane with atomic hydrogen has been studied. This reaction involves both substitution and abstraction. Calculations show that the hydrogen abstraction is the strongest competing channel. The canonical variational transition state theory with a small curvature tunneling correction (SCT) has been used for the kinetic calculation. The theoretical results are in good agreement with the available experimental data. Comparing the reactions of atomic hydrogen with disilane and silane, it can be seen that the reactivity of the Si-H bond is higher in Si2H6than that in SiH4.