沟纹硬皮地蛛粗毒的多肽成分初探

通过高效液相色谱结合MALDI-TOF-TOF质谱对沟纹硬皮地蛛粗毒所含多肽成分进行分离和鉴定.从沟纹硬皮地蛛粗毒中一共鉴定到105种毒素多肽.大多数毒素多肽的分子质量分布范围在1 000~3 500 u(占总数84.8%),还有一部分毒素多肽的分子质量分布范围在3 500~4 500和6 500~8 500 u.与其他蜘蛛种类比较,沟纹硬皮地蛛毒素多肽的分子质量分布特征均不相同,这体现了地蛛科蜘蛛毒液成分的特异性.

Unveiling osteoprotective potential of biologically active naringenin in rats with dexamethasone-induced osteoporosis

Objective To investigate the protective effects of naringenin(NRG)against dexamethasone(DEX)-induced osteoporosis(OP)in rats.Methods Molecular docking of NRG was done with AutoDock Vina 1.2.0 software.Forty-eight female Wistar rats were randomly divided into six groups(n=8 each):normal control(NC),DEX(7 mg/kg,i.m.),NRG-low(NRG-L;25 mg/kg,i.g.),NRG-medium(NRG-M;50 mg/kg,i.g.),NRG-high(NRG-H;100 mg/kg,i.g.),and alendronate(ALN;0.25 mg/d,i.g.)groups.OP was induced by administering DEX once a week for five weeks in all groups except NC group.Begining in the third week after the initial DEX administration,the rats in NRG-L,NRG-M,NRG-H,and ALN groups received the corresponding treatments daily for three weeks,while NC and DEX groups received no additional treatment.Serum samples were collected at the end of the experiment for biochemical,bone turnover,antioxidant,lipid profile,and inflammatory cytokine analyses.Femur bones underwent physical parameter testing and histopathological examination.Results The molecular docking results illustrated that NRG docked with calcitonin(CT),lowdensity lipoprotein(LDL),bone morphogenetic protein(BMP),vascular endothelial growth factor(VEGF)receptor,forkhead transcription factors,and osteoprogenitor cells showed good binding energy.In rats administered with 25,50,and 100 mg/kg NRG,there was a significant enhancement in serum biochemical indices,characterized by a reduction in tartrate-resistant acid phosphatase(TRAP),parathyroid hormone(PTH),and an elevation in osteocalcin(OC)and CT levels(P<0.05,P<0.01,and P<0.001,respectively).Despite no significant changes in thickness,weight,and length(P>0.05),there was a marked increase in bone mineral density(BMD)(P<0.01,P<0.001,and P<0.001,respectively).Antioxidant enzyme markers showed significant upregulation,with higher glutathione,superoxide dismutase,and catalase,and a concurrent decrease in malondialdehyde(MDA)(P<0.05,P<0.01,and P<0.001,respectively).The lipid profile also improved significantly,with lower cholesterol(CH),triglycerides(TG),and low-density lipoprotein(LDL)levels,and an increase in high-density lipoprotein(HDL)level(P<0.05,P<0.01,and P<0.001,respectively).Inflammatory cytokine levels were reduced,as evidenced by decreases in tumor necrosis factor(TNF),interleukin(IL)-6,and IL-1β(P<0.05,P<0.01,and P<0.001,respectively).Furthermore,histological alterations revealed obvious improvements,and the body weight of rats treated with NRG showed an increase compared with DEX group.Conclusion These findings imply that NRG exhibited a protective effect against DEX-induced OP in rats as it promotes the bone formation process by increasing the number of bone turnover markers including OC and CT,and restoring of antioxidant status,lipid metabolism,and inflammatory markers.

一种来源于蜘蛛毒液的新型Nav1.7多肽抑制剂的发现与鉴定

Nav1.7特异性地表达在外周伤害性感觉神经元。临床遗传学、动物模型和药理学研究表明,Nav1.7是一个重要的镇痛药物开发靶点。本研究以沟纹硬皮地蛛(Calommata signata Karsch)毒液为研究对象,通过电刺激采集毒液、反相高效液相色谱分离纯化、质谱鉴定、蛋白质测序以及全细胞膜片钳记录等方法,筛选并鉴定到一种对Nav1.7有抑制作用的新型多肽毒素,命名为APTX-1。质谱鉴定该多肽毒素的分子质量为7815.2 Da;其N端前10位氨基酸序列为ASCKQVGEEC。APTX-1抑制Nav1.7电流具有浓度依赖性,其半数抑制浓度为(0.46±0.08)μmol/L。通道动力学分析显示,APTX-1并不影响Nav1.7的翻转电位、电压依赖性稳态激活曲线和失活曲线,表明该多肽毒素并不影响Nav1.7的离子选择性和电压依赖性。综上所述,本研究获得了一个新型Nav1.7调制剂,并探究了其对Nav1.7的作用特点,为靶向Nav1.7的镇痛药物研发提供了潜在先导分子。

Relation Analysis of Several Agronomic Traits and Single Plant Lint Yield in Upland Cotton with High Quality

[ Objective] The purpose was to study the correlation between main agronomic traits and single plant lint yield in upland cotton with high quality. [ Method] Twenty-four upland cotton lines with high quality were analyzed for single plant lint yield and 10 agronomic traits in a randomized, complete block at the agriculture experimental station of JXAU, Nanchang, China in 2007. They were divided into three types （ high, medium, low yield） based on single plant lint yield by Ward＇s method. A total of 11 traits of three types were compared. Correlation a- nalysis and stepwise regression analysis of 10 agronomic traits to single plant lint yield were carried out. [ Result] There existed statistically sig- nificant difference in bolls per plant, ~int percentage, lint index, fruit node numbers, growth period for three yield types. The high yield type ex- hibited the highest bolls per plant, lint percentage and lint index, the lowest fruit node numbers and the shortest growth period. Bolls per plant, boll weight and single plant lint yield were significantly and positively correlated. Fruit node numbers and single plant lint yield were significantly and negatively correlated. Bolls per plant, boll weight, and fruiting position number were the most important factors influencing single plant lint yield of upland cotton lines with high quality. [ Conclusion ] The results will have certain significance for the development of upland cotton variety with high quality.

Study on Soil Microbiotic Crust and Its Influences on Sand-fixing Vegetation in Arid Desert Region

Based on secular fixed_site data in the artificial sand_fixing vegetation district at the southeast fringe of the Tengger Desert, the formative characteristics of soil microbiotic crusts and its influences on vegetation dynamics were analyzed. Once sand barrier and artificial vegetation have stabilized the surface of the sifting sand, could form aeolian deposition crust and then evolve into algae_dominated crust. Such processes result from the interactions of physical effects of atmospheric dust and silt deposition on sand surface, sinking and raindrop impact, and soil microorganism activities. Under the condition of less than 200 mm precipitation, the presence of microbiotic crust changes the soil hydraulic conductivity, alters the temporal and spatial distribution of the limited precipitation in sand layer and leads to the decline of deep_rooted shrubs. The development of microbiotic crust and subsurface soil affects the plant growth and seed rain distribution, as a result, the diversity of plant species gradually tend to become saturated and finally affects the vegetation stability.

Synthesis of 3 Nitrogen containing Function Substituted Lanosterol Derivatives Inhibitors of (S) Adenosyl L Me thionine:Δ 24(25) Sterol Methyltransferase

Syntheses of 3 ketolanosterol, 3 acetolanosterol, 3 oximolanosterol, 3α and 3β aminolanosterol were described The products have been fully characterized on the basis of their chromatographic (TLC R f, GLC RRTc) and spectral (IR, MS, 1 H NMR, 13 C NMR) properties

A preliminary study on the teratogenesis of dexamethasone and the preventive effect of vitamin B_(12 )on murine embryonic palatal shelf fusion in vitro

Excessive dexamethasone (Dex) administrated into pregnant mice during critical periods of palatal development can produce a high incidence of cleft palate. Its mechanisms remain unknown. Vitamin B12 has been shown to antagonize the tera- togenic effects of Dex, which, however, remains controversial. In this study, we investigated the effects of Dex and vitamin B12 on murine embryonic palatal shelf fusion using organ culture of murine embryonic shelves. The explanted palatal shelves on em- bryonic day 14 (E14) were cultured for 24, 48, 72 or 96 h in different concentrations of Dex and/or vitamin B12. The palatal shelves were examined histologically for the morphological alterations on the medial edge epithelium (MEE) and fusion rates among different groups. It was found that the palatal shelves were not fused at 72 h or less of culture in Dex group, while they were completely fused in the control and vitamin B12-treated groups at 72 and 96 h, respectively. The MEE still existed and proliferated. In Dex+vitamin B12 group the palatal shelves were fused at each time point in a similar rate to controls. These results may suggest that Dex causes teratogenesis of murine embryonic palatal shelves and vitamin B12 prevents the teratogenic effect of Dex on palatogenesis on murine embryos in vitro.

Comparison and Evaluation of Several Dermatophagoides Pteronyssinus Allergen Extracts for Skin Prick Test

Objective To evaluate the significance of several Dermatophagoides pteronyssinus allergen extracts for skin prick test(SPT) in patients allergic to Dermatophagoides pteronyssinus.Methods Two hundred and nineteen patients enrolled in Peking Union Medical College Hospital underwent SPT and serum specific IgE assay to detect the Dermatophagoides pteronyssinus allergen.Three kinds of house dust mite allergen extracts were used for SPT,including the Dermatophagoides pteronyssinus extract prepared by our laboratory(group A),standardized Dermatophagoides pteronyssinus extract(group B),and mixed extracts of Dermatophagoides pteronyssinus and Dermatophagoides farinae(group C).Human serum specific IgE result was regarded as the reference standard for diagnosis of Dermatophagoides pteronyssinus allergy.The receiver operating characteristic(ROC) curve was used to evaluate the diagnostic performance of SPT with the extracts of three groups.Results SPT results showed that the median wheal diameter of group A,group B,and group C was 0.43,0.35,and 0.28 cm,respectively,with significant difference among three groups(P<0.05).The difference was significant between group A and B(P<0.01) as well as group A and C(P<0.01),but not between group B and C(P>0.05).There was no local urticaria or systemic allergic reactions following the procedure of SPT.Local reaction was observed in 5 patients and delayed reaction was in 2 patients of group A.As for group B and C,local reaction occurred in 3 cases and delayed reaction in 2 cases in each group.The area under ROC curve of SPT with extract in group A,group B,and group C was 0.765,0.801,and 0.782,respectively.Based on the detection results of serum specific IgE,the sensitivity of SPT in diagnosis of Dermato-phagoides pteronyssinus allergy with extract of group A,group B,and group C was 92.4%,87.0%,and 81.5%,and the specificity was 60.6%,73.2%,and 74.8%,respectively.Conclusion The Dermatophagoides pteronyssinus extract for SPT prepared by our laboratory offers good sensitivity and specificity comparable to commercially available allergen extracts,and it may be an appropriate candidate for clinical screening and diagnosis of Dermatophagoides pteronyssinus allergy.

Geographic variation and genetic performance of Picea koraiensis in growth and wood characteristics

Eight provenances of 19-year-old Picea koraiensis Nakai from the provenancetrials of Maoershan (45°20′N, 127°30′E), Liang-shui (47°10′N, 128°53′E) and Jiagedaqi(50°24′N, 124°07′E) in Northeast China were investigated to analyze the genetic variation ingrowth characteristics (tree height and diameter) and wood characteristics (tracheid length,tracheid diameter, tracheid wall thickness, annual ring width as well as wood density). Greatvariation in height growth and breast height diameter growth was observed among the provenances, andalong with the increase of tree age, these provenances presented different geographic adaptability.The growth characteristics of Picea koraiensis stand at age of 10 in Maoershan and Liangshuiprovenance trials had a positive correlation with longitude, and with increase of tree age to 15 and19, the tree growth of the provenances displayed a significant positive correlation with latitudeas well as altitude. For wood characteristics, great variation was also found among the provenances.There exists a close relation between growth characteristics and wood properties of the provenance.The height and breast height diameter growth of the provenance had a positive correlation withtracheid diameter and annual ring width, and a negative correlation with tracheid wall thickness andwood density. Genetic performance of the provenance in all above characteristics was alsoinvestigated in order to provide more useful information for comprehensive selection of this speciesfor pulpwood and plywood production.

Mesomechanics coal experiment and an elastic-brittle damage model based on texture features

To accurately describe damage within coal, digital image processing technology was used to determine texture parameters and obtain quantitative information related to coal meso-cracks. The relationship between damage and mesoscopic information for coal under compression was then analysed. The shape and distribution of damage were comprehensively considered in a defined damage variable, which was based on the texture characteristic. An elastic-brittle damage model based on the mesostructure information of coal was established. As a result, the damage model can appropriately and reliably replicate the processes of initiation, expansion, cut-through and eventual destruction of microscopic damage to coal under compression. After comparison, it was proved that the predicted overall stress-strain response of the model was comparable to the experimental result.

Sea Turtles in Vietnam： On the Edge of Extinction

Five species of foraging and breeding sea turtles have been identified in Vietnam, they are Green turtle （Chelonia mydas）, Loggerhead turtle （Caretta caretta）, Olive ridley turtle （Lepidochelys olivacea）, Hawksbill turtle （Eretmochelys imbricata） and Leatherback turtle （Dermochelys coriacea）. Among them, with the exception of Loggerhead turtle （Caretta caretta）, four species have been being lay eggs on the beaches along the country. However, these populations have been strongly suffered by human activities for decades. The number of foraging and breeding Hawksbill and Leatherback sea turtles has dramatically decreased, and Olive Ridley turtle has almost disappeared on their traditional nesting beaches. Beside the reason of harvesting eggs and nesting turtles by catch or by purpose, the developments in coastal areas where sea turtles laying eggs such as in shrimp aquaculture, tourist resort and residential area developments etc., also contributed to this decline of sea turtles. Despite the fact that the recent raising awareness programs on protection and conservation of the sea turtle were very well done with the participation of many organizations and provinces, this important animals still face the risk of extinction in Vietnam.

Susceptibility of pine stands to bark stripping by chacma baboons Papio ursinus in the Eastern Highlands of Zimbabwe

The aim of this study was to determine the susceptibility, intensity and distribution of pine trees to bark stripping by chacma baboons Papio ursinus in three plantations in the Eastern Highlands of Zimbabwe. The number of plots/ha, stripped trees/ plot and stripped trees/ha was recorded during the pre-rainy, rainy and post-rainy seasons from August 2006 to May 2007. During data collection, altitude, aspect, season and other site predictor variables （e. g., roads and fire traces, water points, indigenous vegetation conservation areas, crop felds, human settlements, wattle scrubs, rocky areas, open grasslands, earlier stripped sites and roost sites） were recorded for each plot in association with selected predictor variables within plantation estates. Data on the number of stripped plots/ha, stripped trees/plot and stripped trees/ha were analysed as dependent variables using the Generalised Linear Model （GLM） through SPSS version 15 （2006） to determine which predictor variables were significantly related to bark stripping. Differences between means were tested using Bonferroni tests with a 5 % level of significance. Our findings show that bark stripping of pine trees by baboons occurred at all altitudes and aspects. Overall, the number of bark stripped trees/ha did not significandy vary by season. The number of bark stripped plots/ha was lower during the pre-rainy season than the rainy season, whereas the number of bark stripped trees/plot was higher during the pre-rainy than the rainy season. Bark stripping of pines occurred more often in the vicinities of areas with abundant food and water

Consumption and species preference for house construction wood in central highlands of Ethiopia–implications for enhancing tree growing

A study was conducted in central Ethiopian highland in 2008 to investigate the consumption of house construction wood, the tree species preference for construction wood and the forthcoming conditions of this forest product and possible strategies for future availability. Twenty-four iron-roofed houses and twenty-eight thatch-roofed houses belonging to thirty-six farm households were investigated for types, volumes and sources of construction wood used. It was found that an average farmhouse with a floor space of 57 m^2 consumed about 13.7 m^3 of wood. Both floor space and wood consumptions vary with house types An average iron-roofed house with floor space of 51.9 m^2 consumed 16.8 m^3 of wood and an average thatch-roofed house with mean floor space of 28.6 m^2 consumed 3.2 m^3 of wood. Family size and floor space were the major factors influencing construction wood consumption. An average living house was composed of woods of 39.3% ,luniperus procera, 5.6% Cupressus lusitanica, 29.2% Eucalyptus globulus and 26% Eucalyptus camaldulensis. The wood volume from the first two species and half that of the third species were obtained from state forest which is currently banned from any construction wood extraction and hence there is a shortage of around 59.5% of woods. We suggest the promotion of various tree planting approaches to increase the wood supply and the use of alternative local materials like soil bricks for house construction.

Holocene Paleoseismic Activity Along the Northern Piedmont Fault of the Hengshan Mountain, South of Datong Basin in Shanxi Province

Our field investigation indicates that the northern piedmont fault of the Hengshan Mountain has dislocated proluvial fan and terrace I of the gully mouth on the northern border of the Hengshan Mountain. Stratigraphic age data indicates that the surface layer in the middle and rear part of the proluvial fan and on the terrace I of the gully mouth on the mountain border consists of sediments of about 5200～6800a B.P. The Hezhuang and Niucaoyu trenches excavated in the front of Hengshan Mountain revealed that 3 paleoseismic events have occurred along the northern piedmont fault of Hengshan Mountain since the early Holocene. The 3 paleoseismic events occurred in 2260±190～4370±150a BP, nearly 5628±150a BP, and 8083±250～8430±720a BP, respectively, and their recurrence interval is 2313a,2628a and 2471a on average. The coseismic vertical displacement produced by these events is 1 0～3 0m. The elapsed time of the latest movement along the fault has exceeded the recurrence interval of these paleoearthquakes. Thus, there exists the possibility of strong earthquake occurrence along the fault from now onward, so the fault is in need of observation.

A Survey on TCM Treatment of Polymyositis and Dermatomyositis

Polymyositis is an illness characterized by inflammation of the muscle(s) with uncertain etiological causes. Most of the physicians think that viral infection, disturbances of immune functions and/or pathological vascular changes might be responsible for the condition.

New method of calculating formation parameters of low permeability gas reservoir

The data of modified isochronal testing of gas well is just used to calculate gas well deliverability. Fully utilizing well test data make it possible to obtain formation parameters, such as gas well deliverability, effective permeability and skin factor at the same time. Based on transient flow theory, the pressure drawdown equation of gas unsteady seepage can be deducted. One simulated case is used to illustrate the applicability of the proposed method. The result of analyzed case shows that the proposed method can provide accurate estimate of formation permeability and skin factor compared with the method of Homer curves.

Clinical, brain electric earth map, endothelin and transcranial ultrasonic Doppler findings after hyperbaric oxygen treatment for severe brain injury

目的 探讨高压氧治疗重型颅脑损伤的疗效及机制。方法 重型颅脑损伤患者 35例为治疗组 ,2 0例为对照组 ,观察高压氧治疗前后临床 (GCS)、脑电地形图 (BEAM)、血内皮素 (ET)、经颅多普勒超声 (TCD)及预后 (GOS)的变化。结果 治疗组患者经高压氧治疗后临床 (GCS)、脑电地形图及预后均明显改善 ,与对照组相比有统计学意义。高压氧治疗 1个疗程后 ,治疗组血内皮素由 91 2 4± 12 18ng/L下降到 6 8 88± 14 37ng/L(P <0 0 1) ;经颅多普勒超声示大脑中动脉Vm也由 6 4 2± 4 8cm/s下降到 51 6± 4 2cm/s(P <0 0 1) ;同时 ,大脑中动脉VsPI也明显下降。统计学有显著性意义 (P <0 0 1)。结论 高压氧治疗能够明显改善重型颅脑损伤患者的临床、脑电地形图及预后 ,并且通过降低急性期血内皮素、改善大脑中动脉血流速度及血管阻力来改善重型颅脑损伤后脑血管痉挛及脑缺血缺氧。同时 ,降低颅内压是高压氧治疗重度颅脑损伤的重要机制之一。

恐龙没有灭绝

满天的星星调皮地眨着眼睛.望着星星我睡意全无,满脑子的恐龙跑来跑去,折腾得我无法合眼.我这个"龙的传人",居然无法探究出"恐龙灭绝之谜",真苦恼."砰"一声巨响,一架碟形飞形物停在我的窗前,一个"怪物",不,是外星人,它穿窗而过站在我的床前,恐惧一下子揪住了我的心.

Development of Soil Crusts Under Simulated Rainfall and Crust Formation on a Loess Soil as Influenced by Polyacrylamide

This study evaluated the morphological characteristics and dynamic variation in characteristics of soil crust and iden-tified the relationships between soil crust and splash erosion under simulated rainfall.The effect of polyacrylamide (PAM) on soil aggregate stabilization and crust formation was also investigated.A laboratory rainfall simulation experiment was carried out using soil sample slices.The slices were examined under a polarized light microscopy and a scanning electron microscope (SEM).The results revealed that the soil crusts were thin and were characterized by a greater density,higher shear strength,finer porosity,and lower saturated hydraulic conductivity than the underlying soil.Two types of crusts,i.e.,structural and depositional crusts,were observed.Soil texture was determined to be the most important soil variable influ-encing surface crust formation;depositional crust formation was primarily related to the skeleton characteristics of the soil and happened when the soil contained a high level of medium and large aggregates.The crust formation processes observed were as follows:1) The fine particles on the soil surface became spattered,leached,and then rough in response to raindrop impact and 2) the fine particles were washed into the subsoil pores while a compact dense layer concurrently formed at soil surface due to the continual compaction by the raindrops.Therefore,the factors that influenced structural crust formation were a large amount of fine particles in the soil surface,continual impact of raindrops,dispersion of aggregates into fine particles,and the formation of a compact dense layer concurrently at the soil surface.It was concluded that the most important factor in the formation of soil crusts was raindrop impact.When polyacrylamide (PAM) was applied,it restored the soil structure and greatly increased soil aggregate stabilization.This effectively prevented crust formation.However,this function of PAM was not continuously effective and the crust reformed with long-term rainfall.In conclusion,this study showed that soil micromorphological studies were a useful method for evaluating soil crust formation.