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The safety evaluation of timosaponin BII (TBII) in beagle dogs with toxicokinetic study was performed. For the acute oral toxicity study, the minimum lethal dose (MLD) of TBII was more than 2000 mg/kg and suggested the characteristics of absorption saturation. For the 28-day repeated dose oral toxicity and toxicokinetic studies, there was no significant effect on all test parameters except for prolonged APTT in the 60 and 180 mg/kg groups, which recovered after withdrawal. The increase of drug exposure of 180 mg/kg group was not proportional to the increase of administration dose, showing the characteristics of absorption saturation.

The aim of this research was to determine the chemical composition, antioxidant and antibacterial properties of the essential oils from Cynanchum chinense and Ligustrum compactum and isolation of antioxidant and antibacterial constituents from the essential oils. Thirty-eight components were identified in essential oils. Based on bioactivity-guided fractionation, guaiacol, linalool and 2-phenylethanol were isolated and identified as active constituents. Both L. compactum flower oil and 2-phenylethanol showed high antibacterial performance, with inhibition zone from 22.8 ± 0.8 to 11.9 ± 2.0 mm at highest concentration, and minimum inhibitory concentration values ranging from 0.25% to 1%. In both DPPH and ABTS assay, the active constituent guaiacol (IC50 = 4.15 ± 0.72 and 9.12 ± 0.98 μg mL(-1), respectively) exhibited high antioxidant activity, and the oils showed moderate antioxidant activity. These results indicate potential efficacy of active constituents and essential oils of L. compactum and C. chinense to control food-borne pathogenic and spoilage bacteria.

Timosaponin BII (TBII), a major steroidal saponin isolated from Anemarrhena asphodeloides Bge., displays a variety of promising pharmacological activities, such as neuroprotection, enhancement of learning and memory, vascular protection and inhibition of platelet aggregation; therefore, it has been developed as a pharmaceutical for prevention or treatment of dementia. Given the safety concerns surrounding timosaponins and the absence of studies on the safety of TBII, the potential toxicity of TBII was evaluated in toxicity and toxicokinetic studies in rats. In the acute oral toxicity study, loose stools were observed in rats receiving 4000 mg/kg, and the symptoms recovered within 1 day. In the 28-day repeated-dose oral toxicity and toxicokinetic study, rats receiving 540 mg/kg showed loose stools and a slight deceleration of body weight growth in both sexes, and the females also showed a slight decrease in food consumption. Moreover, urinalysis indicated reversible treatment-related toxicity in rats receiving 540 mg/kg. The toxicokinetic study demonstrated a dose-dependent increase in systematic exposure to TBII after 28 successive days of oral treatment with TBII. The accumulation coefficients of TBII were 4.35, 1.70 and 1.81, respectively, in rats that received 60, 180 and 540 mg/kg. The no-observed-adverse-effect level (NOAEL) is proposed to be 180 mg/kg.

In this paper wide-angle reflection and refraction data is used along Tanggu-Yutian profile and other five profiles intersecting with this profile, and the seismic sounding data was processed and interpreted comprehensively along Tanggu-Yutian profile. The purpose is to find out the basic features of 2-D velocity structure, spacial distribution of faults, geological structure condition of shallow and deep crust in the northwest margin of Bohai bay and its adjacent area. The result shows that obvious layered structure appears along the profile, the crustal thickness increases gradually from south to north, and the crustal velocity structures in different regions have obvious inhomogeneity in the lateral and vertical directions. The Moho is a slope between Tanggu and Ninghe near Bohai bay. The crustal depth deepens gradually towards north from 28 km in Tanggu to 31 km in Ninghe.

The authors processed the seismic refraction Pg-wave travel time data with finite difference tomography method and revealed velocity structure of the upper crust on active block boundaries and deep features of the active faults in western Sichuan Province. The following are the results of our investigation. The upper crust of Yanyuan basin and the Houlong Mountains consists of the superficial low-velocity layer and the deep uniform high-velocity layer, and between the two layers, there is a distinct, and gently west-dipping structural plane. Between model coordinates 180–240 km, P-wave velocity distribution features steeply inclined strip-like structure with strongly non-uniform high and low velocities alternately. Xichang Mesozoic basin between 240 and 300 km consists of a thick low-velocity upper layer and a high-velocity lower layer, where lateral and vertical velocity variations are very strong and the interface between the two layers fluctuates a lot. The Daliang Mountains to the east of the 300 km coordinate is a non-uniform high-velocity zone, with a superficial velocity of approximately 5 km/s. From 130 to 150 km and from 280 to 310 km, there are extremely distinct deep anomalous high-velocity bodies, which are supposed to be related with Permian magmatic activity. The Yanyuan nappe structure is composed of the superficial low-velocity nappe, the gently west-dipping detachment surface and the deep high-velocity basement, with Jinhe-Qinghe fault zone as the nappe front. Mopanshan fault is a west-dipping low-velocity zone, which extends to the top surface of the basement. Anninghe fault and Zemuhe fault are east-dipping, tabular-like, and low-velocity zones, which extend deep into the basement. At a great depth, Daliangshan fault separates into two segments, which are represented by drastic variation of velocity structures in a narrow strip: the west segment dips westward and the east segment dips eastward, both stretching into the basement. The east margin fault of Xichang Mesozoic basin features a strong velocity gradient zone, dipping southwestward and stretching to the top surface of the basement. The west-dipping, tabular-like, and low-velocity zone at the easternmost segment of the profile is a branch of Mabian fault, but the reliability of the supposition still needs to be confirmed by further study. Anninghe, Zemuhe and Daliangshan faults are large active faults stretching deep into the basement, which dominate strong seismic activities of the area.

In this paper wide angle reflection and refraction data is used to obtain the 2-D velocity structure, spatial distribution of faults, and geological structure condition along Wuqing-Beijing-Chicheng profile. The results reveal strong vertical and lateral heterogeneities in the crust. The crust has layered features and its thickness gradually increases from 31.0 km in Wuqing to 40.0 km in Yanqing. The strong variation of topography of the crustal interfaces appears around the Beijing area, and the Moho deepens rapidly in the northwest of Beijing area. Five shallow faults in the crust are inferred along this profile, based on the crustal velocity structures and the variations of the crustal interfaces

In this paper, the deep crustal structures in Wutai mountain area are studied by using deep seismic sounding (DSS) data obtained from wide-angle reflection/refraction profiles which pass through Shanxi down-faulted zone and Wutai mountain area. The results show that the crust in this area presents obviously layered structures. The boundary interface between upper and lower crust is determined by means of reliable intra-crust reflected waves P3 that can be traced continuously. The thickness of upper crust is 23~28km, and the depth of Moho discontinuity is 39~43 km. The Moho discontinuity in Wutai mountain area is the deepest in this region. In Wutai mountain and its adjacent areas, the crust structures have strong inhomogeneous characteristics. The large-scale low velocity bodies in upper crust and strong intra-crust reflected wave groups can be regarded as a sign of magma activity in deep crust. The breaking of intra-crust interfaces and the local discontinuation of seismic wave group Pm as well as existence of deep crustal faults and so on indicate that the crust in this region suffered violent squeeze, deformation, and tectonic activities. Therefore the complex topography and anomalous structural characteristics in deep and shallow crust have been formed in this region.

In this paper, the abnormal characteristics of the crustal structures in the seismic active region, Yanqing-Huailai and Zhangbei-Shangyi, are obtained by means of comprehensively interpreting and studying the data of deep seismic sounding profiles passing through the northwestern part of Zhangjiakou-Bohai seismic zone. The results show that the fluctuation of crystalline basement in the study region is obvious and that there exist considerable differences in depth in different geological units. The locally abrupt variation of crystalline basement depths may be regarded as a mark of existence of crystalline basement faults. These crystalline basement faults and deep crustal faults provide a pass for the magma upwelling, resulting in the strong inhomogeneity of crustal structures. These phenomena of the complex seismic reflected waves and locally discontinuous reflection zones with different energy indicate that the intensive squeeze and deformation of crust took place, which have led to the complex crustal structures and offered the dynamic source for the earthquake occurrence in this region. The low velocity bodies in different depths of crust and the local interface C1 in Zhangbei-Shangyi region may result from repeated magmatic activities. The certain stress accumulation in the brittle upper crust can cause the occurrence of earthquake under the action of local tectonic activity.

Reflected seismic waves from Moho discontinuity are recorded by a specially designed threedimensional observation system at the northeast edge of Qinghai-Tibet Plateau and the Moho geometry in the investigation region is reconstructed by three dimensional (3-D) inversion method. The 3-D structure images of Moho and deep crustal faults are obtained. Overall, the Moho discontinuity in survey region gradually slopes down from northeast to southwest direction, and in the interior of distinct blocks, the inclination pattern is different, which reflects the differences among different blocks and indicates that their complication degrees are not alike. The Moho geometry in Ordos block varies gently. Its interior structure is integral and hard. The dipping trend of Moho discontinuity at the arc tectonic zone takes a reverse, which may suggest that the Moho discontinuity suffered obvious torsional deformation under the action of compression and deforming tectonics. The Moho of Qinqi block presents comparatively steep dipping trend and at the contact zone where its southeast end meets with the arc zone, the Moho discontinuity shows local updoming, which may be regarded as a sign of strong crustal torsional deformation. To synthesize the two dimensional (2-D) and 3-D results suggests that the special and complex tectonic deformation environment provides the geological condition and deep background for the development as well as occurrence of Haiyuan strong earthquake with magnitude 8.6.

In this paper, the data from deep seismic reflection and wide angle reflection profiling completed in Sanhe-Pinggu strong earthquake (M=8.0) region are comprehensively studied and interpreted. The result shows that the layered crustal structures obtained by the two investigation methods are basically consistent. In Sanhe-Pinggu strong earthquake region, the fluctuation of basement structures is considerable, shallow faults well developed, and the thickness of upper crust and the depth of Moho discontinuity are 21–23km and 36–37km, respectively. Among several faults determined by this study, the Xiadian fault is a tectonic zone with obvious characteristic and coexistence of both shallow and deep faults. Surrounding the focus, anomalous velocity structures and complex geological tectonic environment mean that these positions are favorable for strong earthquake developing and occurring. The phenomena of Moho discontinuity fluctuation and rather thick overlapping reflection layers and existence of locally complex cuneiform reflection zones indicate that the strong compression and deformation of the crustal structures had taken place in this region, and these phenomena also reflect that magmatic activity put strong reformation on material and structures in lower crust to result in complicated deep crustal structures in the region which may be considered as deep background for the development and occurrence of Sanhe-Pinggu strong earthquake (M=8.0).

We have obtained tomographic images of P- and S-wave velocity structures and VP/VS perturbation at different depths benenth the Changbaishan Tianchi volcanic region by inversion of three-dimensional (3-D) fine velocity structure in the upper crust of the region. The inversion is based on reflected waves from Moho obtained by a 3-D seismic transmission experiment in the study area. The result shows that the heterogeneity of the velocity structure in the Tianchi volcanic region and its surrounding areas is closely related to the geological structure and existence of the magma system in the area. The distribution of obvious P-wave low-velocity anomalous bodies and high VP/VS perturbation image suggests that the media are in a “soft and high-temperature” state. This conclusion is consistent with the results of wide-spread geothermal anomaly and low Q-value structure obtained by other studies.

2-D crustal velocity structure and v P/v S are obtained by processing and interpretation of S-wave data from Maqen-Jingbian deep seismic sounding (DSS) profile. The result shows that there exist obvious differences in 2-D S-wave velocity structure and v P/v S ratio structure along the profile. The S-wave velocities are low and v P/v S ratio is high for the western section of the profile and Haiyuan region, while they are normal for the middle and eastern sections. The changes in lithologic characters of two major anomalous zones are discussed according to lateral variation of S-wave velocity structure and v P/v S ratio structure. It is concluded that the development and occurrence of the Haiyuan strong earthquake is not only related to tectonic activities, but also to lithologic characters of the region.

Using 2-D ray tracing software package, the crustal and upper-mantle velocity structure and deep features of the Changbaishan Tianchi volcanic region and its vicinity are studied through travel-time fitting and synthetic seismogram computation with deep seismic sounding (DSS) data acquired along the Changbai-Dunhua profile. The results show that the crust of this region is separated into the upper crust and the lower crust by the interface C2. The upper crust is 19–23km thick and P-wave velocity is 6.00–6.25 km/s. The lower crust is 12–17km thick, which is composed of a homogeneous velocity layer and a crust-mantle transition layer 6–9km thick. Crustal thickness is 31–33km in Dunhua and becomes gradually greater southeastwards to its maximum value of 39km in the Tianchi volcanic region. In the Tianchi volcanic region, there exists a low-velocity body in the crust, whose velocity is about 0.15 km/s lower than that of the adjacent medium. Results of seismic profiling, seismic tomography, and magnetotelluric sounding suggest that in Tianchi volcanic region there is a low-velocity, low-density, and low-resistivity anomalous body, which may indicate the existence of a magma chamber in the crust.

The magma system of Changbaishan-Tianchi Volcanic region is studied with three-dimensional deep seismic sounding (DSS) technique. The results show that the magma system of Changbaishan-Tianchi volcanic region, mainly characterized by low velocity of P wave, can be divided into three parts in terms of depth. At the depth range of 9–15 km, the distribution of the magma system is characterized by extensiveness, large scale and near-SN orientation. This layer is the major place for magma storage. From the depth of 15 km down to the lower crust, it is characterized by small lateral scale, which indicates the “trace” of magma intrusion from the upper mantle into the crust and also implies that the magma system most probably extends to the upper mantle, or even deeper. (less than 8–9 km deep), the range of magma distribution is even smaller, centering on an SN-oriented area just north of the Tianchi crater. If low velocity of P wave is related to the magma system, it then reflects that the magma here is still in a state of relatively high temperature. In this sense, the magma system of Changbaishan-Tianchi volcanic region is at least not “remains”, in other words, it is in an “active” state.

To establish a method for determining the content of 2,4-toluenediamine, a urinary metabolite of toluene diisocyanate, by gas chromatography.Urine samples were collected, and acidification, extraction, derivatization, separation with a capillary column, and detection with an electron capture detector were performed. The target compound was qualified by retention time and quantified by peak area.The concentration of 2, 4-toluenediamine showed a linear relationship with peak area within 0.0∼40 ng/ml, with a correlation coefficient 0.9995; the limit of detection was 0.44 ng/ml, the lower limit of quantification was 1.47 ng/ml, the relative standard deviation was 1.85%∼4.05%; the recovery rate was 97.98%∼99.28%.The method has the advantages of high sensitivity and high accuracy and can be used for determination of 2, 4-toluenediamine in urine.

To test the immunity of peritoneal monocytes against Plasmodium yoelii infected red blood cells (target cells).Saponinized Plasmodium yoelii infected red blood cells (SPRBC, Ghost erythrocyte) were used to immunize mice i.p twice. Three weeks later, the infected red blood cells were injected i.p.; 90 min later, the total peritoneal cells were isolated and washed for scanning electromicroscopy to observe the effects of the peritoneal monocyte to the target cell.The peritoneal cells of the immunized mice were activated after 90 min of the challenge of target cells. The size of the cell was not even and the pili on the cell surface turned to be long and densed. Cell interconnections were found among the cells. In some peritoneal monocytes, their cell plasma were scattered (omlette-like) or with the shape as "cellular bomb". The scattered or the sheeted pili and spredding cell plasma could adhere to the target cells which were perforated densely and damaged.The protective adaptive immunity exists in the peritoneal monocytes of immunized mice.

To observe the morphological characteristics of Plasmodium yoelii schizogony in their ghost erythrocytes.Saponify, hypotonic shock, and electron microscopy were used to observe the different fashions of erythrocytic parasites and their characteristic organellae in ghost erythrocytes.The malarial parasites and their fine structures were dramatically well preserved in the ghost erythrocytes, such as the ring-like early trophozoites, the brassiere-like early schizonts, the emerging buds on the surface of late schizonts, and the grape-cluster like late schizonts. The cytostome, food vacuole, and crystallized malarial pigments were found in the early trophozoites. The proliferations of nucleoplasma and nuclear membrane as well as and the clot-like nuclear division were followed by the budding during the schizogony.The saponify technique that makes the erythrocytic malaria parasites and their fine organellae to be dramatically revealed in their ghost erythrocytes, may be a useful method in the Plasmodium biological research and anti-malaria immunological researches.

To explore the characteristics of protective immunity against Plasmodium yoelii (P.y.) infection by asexual blood-stages cellular vaccine.The particulate vaccines were constructed by saponin or double-distilled-water lysed parasitic red blood cells and inoculated into BALB/c mice by intraperitoneal injection (i.p.). Each group was challenged by the lethal erythrocytic P.y. parasites, and then their parasitemia and survival rates were detected. Expressions of interleukin-4 (IL-4) and interferon-gamma (IFN-gamma) were detected by RT-PCR. ELISA showed the serum antibodies against the malaria challenge and their-subclasses. Special membrane protein was recognized by immunofluorescence assay.The vaccination with saponified erythrocytic parasites protected the immunized mice against P.y. challenge, while double-distilled-water lysed vaccine did not (P0.01). This protection was characterized by the increase of both IFN-gamma/IgG2a and IL-4/IgG1. Meanwhile, MHC class I alpha chain molecule was recognized on the membrane of infected-erthythrocyte.Saponified P.y. asexual blood-stage cellular vaccine has a significantly high protective immunity against this lethal P.y. malaria, and the immunity may be associated with the expression levels of IgG2a and IFN-gamma. MHC class I alpha chain on infected erythrocytes may play an important role in the successful immunization.