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Large-scale disasters can disproportionately impact different population groups, causing prominent disparity and inequality, especially for the vulnerable and marginalized. Here, we investigate the resilience of human mobility under the disturbance of the unprecedented ‘720’ Zhengzhou flood in China in 2021 using records of 1.32 billion mobile phone signaling generated by 4.35 million people. We find that although pluvial floods can trigger mobility reductions, the overall structural dynamics of mobility networks remain relatively stable. We also find that the low levels of mobility resilience in female, adolescent and older adult groups are mainly due to their insufficient capabilities to maintain business-as-usual travel frequency during the flood. Most importantly, we reveal three types of counter-intuitive, yet widely existing, resilience patterns of human mobility (namely, ‘reverse bathtub’, ‘ever-increasing’ and ‘ever-decreasing’ patterns), and demonstrate a universal mechanism of disaster-avoidance response by further corroborating that those abnormal resilience patterns are not associated with people’s gender or age. In view of the common association between travel behaviors and travelers’ socio-demographic characteristics, our findings provide a caveat for scholars when disclosing disparities in human travel behaviors during flood-induced emergencies.

The complex micro-interfacial interaction theories of heavy metal ions such as Pb(II) and Cd(II) adsorption on fine sediment in aqueous solution were not systematically investigated. The aim of this work was to reflect the micro-interfacial adsorption characteristics. Sediment samples were collected from an estuary. The Isothermal and kinetics adsorption experiment were done to acquire the data. Isothermal, kinetics, film diffusion and intraparticle diffusion models were adopted to fit the adsorption experimental data. The results indicated that the Langmuir, Freundlich and Temkin models were suitable for analyzing the isothermal experimental data. The maximum adsorption capacities of Pb(II) and Cd(II) on the sediment were 1.1377 and 0.9821 mg·g−1, respectively. The qm and KL of the Langmuir model, Kf and nF of the Freundlich model, and b and A of the Temkin model all exhibited a power function relationship with the initial adsorbate concentration. The pseudo-second-order model provided a better fit for the experimental kinetics data compared with the fit of the pseudo-first-order and Elovich models. The pseudo-second-order parameters k2 and qe of Pb(II) and qe of Cd(II) both had a power function relationship with adsorption time, additionally, the k2 of Cd(II) had an exponential function relationship with adsorption time. The liquid-film diffusion parameters kfd of Pb(II) and Cd(II) were 0.0569 and 0.1806 min−1, respectively. The intraparticle diffusion parameter kid values of Pb(II) and Cd(II) were 0.0055 mg·g−1·min1/2 and 0.0049 mg·g−1·min1/2, respectively. The physical significance of the model parameters showed that Pb(II) adsorption on sediment was stronger than Cd(II). The results of this study provided a theoretical reference for the micro-interfacial mechanism of heavy metal ion adsorption on sediment.

The factors affecting debris flow runout volume changed considerably in the Wenchuan earthquake area. The main characteristic parameters for calculating the debris flow runout volume, namely, channelized landslide dam volume are first used to establish empirical models. A new empirical statistical model is established by applying a multivariate regression analysis to the runout volumes of dam-break and non-dam-break debris flows. Additionally, FLO-2D is used to simulate the debris flow runout volumes under the non-dam-breaking and dam-breaking scenarios. When the rainfall frequency is P = 1%, the predicted runout volumes in the Huaxi gully are 24.48 × 104 m3 under the non-dam-breaking scenario and 43.41 × 104 m3 under the dam-breaking scenario. The runout volume in the dam-breaking scenario is 6.07 × 104 m3 more than 1.77 times that in the non-dam-breaking scenario. The predicted runout range of the dam-breaking scenario is 1.16 times that of the non-dam-breaking scenario. The predicted alluvial fan areas and average accumulation depths in the dam-breaking scenario are larger than those in the non-dam-breaking scenario. The predicted runout volume of the dam-breaking scenario is 5.58 × 104 m3 which is less than the actual surveyed volume (48.99 × 104 m3). The relative error and accuracy of the numerical simulation results are −11.39 and 88.61% for the dam-breaking scenario. The new runout volume model was developed in catchments with abundant loose materials in the Wenchuan earthquake area and can thus be applied to debris flow gullies in meizoseismal areas with newly fractured regolith and abundant loose material to estimate runout volumes. The results of this study will help authorities select safe sites for future rehabilitation and relocation projects and can also be used as an important basis for debris flow risk management.

This study represents an approach to assess the hydrologic effectiveness of low impact development (LID) practices based on the expected runoff process with different objectives and land utilization. The proposed approach is to simulate runoff hydrograph rather than several indices (e.g., runoff initiation, peak flow, and runoff volume) to avoid the uncertainties under a certain rainfall scenario. A rainfall-runoff model of a residential district in China, constructed based on the stormwater management model (SWMM), is auto-calibrated (validated) based on 12 (25) observed rainfall and runoff events using model-independent parameter estimation (PEST). The priority sites and parameters for LID practices for different objectives are auto-calculated using PEST based on the calibrated model and different expected runoff processes. The expected runoff processes are simulated from the calibrated model with four impervious cover scenarios corresponding to 5-year, 2-h duration design storm. The study illustrates that (i) the proposed approach can auto-optimize runoff manage strategies based on LID practices and land; (ii) the design parameters of LID practices can be auto-calculated and that simulated runoff processes are in near perfect agreement with expected runoff processes; (iii) this approach can auto-optimize any specific parameters of the SWMM and LID practices without changing those determined parameters. Our simple, but quantitative, approach for identifying potential LID sites and design parameters based on land can better inform the hydrologic effectiveness of LID practices for managing runoff.

In this work, fluorinated graphene nanoscrolls (FGN) were synthesized via facile chemical methods under simple and mild conditions. Interestingly, the formation of the featured FGN was significantly solvent sensitive. Experimental results indicated that in the presence of aprotic solvent, for example, N,N dimethylformamide (DMF), the reaction system inclined to form the interesting FGN nanostructures. The structure and morphology of the prepared FGN were detailed characterized by atomic force microscopy (AFM), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-ray diffraction (XRD) etc. The obtained FGN was used as a cathode material for primary lithium ion batteries with superior discharge specific capacity (eg. 979.3 mAhg-1), stable discharge platform and high energy density (eg. 2287.9 Wh kg-1), which fosters it a high density, low cost and durable candidate for cathode material for lithium ion batteries..

Water plays an essential role in social and economic sustainable development, and the relationship between socio-economic development and water resources sustainable utilization has been an important issue in water resources management. We aim to propose a water resources vulnerability assessment index with the dimensions of exposure, sensitivity and adaptability, and establish a water resources system model over the Pearl River Delta network river region based on the Vulnerability Scoping Diagram (VSD) framework and System Dynamics (SD) model. The city of Zhongshan, which is located in the Pearl River Delta is used as a case study. The vulnerability of the water resources in Zhongshan from 2021 to 2050 is simulated in four different scenarios (normal, technical innovation, social economic improvement, and comprehensive development models). The results showed that the vulnerability in all four scenarios span three grades in 30 years, including moderately vulnerable, slightly vulnerable, and not vulnerable. Among them, similar trends were found between scenarios 1 and 3, and between scenarios 2 and 4. Furthermore, the vulnerability level in scenarios 2 and 4 was lower than that in scenarios 1 and 3. The vulnerability of both scenarios 2 and 4 decreased first and then increased, with the average values of 24.64 and 27.63, respectively. Scenario 2 experienced 7 years of not vulnerable (2034 to 2040) and 23 years of slightly vulnerable (2021–2033, 204–2050), scenario 4 experienced 5 years of not vulnerable (2032–2036), 21 years of slightly vulnerable (2021–2031, 2037–2046), and 4 years of moderately vulnerable (2047–2050). Although the vulnerability of scenario 4 was slightly worse than scenario 2, its adaptability to economic and social development, water resources, and water environment was much higher than scenario 2. Considering the extent of socio-economic development and the level of adaptability of the local water resources and water environment, the study concluded that the comprehensive development model is more suitable for cities in the network river area. In this scenario, sustainable water use and management can be made possible through policy regulation that encourages higher water efficiency, sewage reuse rate, and centralized sewage treatment rate.

This study aimed to explore the effects of postnatal low-concentration arsenic exposure on learning, social skills and frontal cortex neurogenesis in rats. Water-based arsenic exposure rat models were established on postnatal days 4–10 (P4-P10). The experimental animals were divided into four groups: the control group, a 15 μg/L As 2 O 3 water group, a 30 μg/L As 2 O 3 water group, and a 45 μg/L As 2 O 3 water group. Cognitive function was examined with the Morris water maze, anxiety-like behavior with the open field test and light-dark box test, and social skills with a social interaction test. The frontal cortices of pups from each experimental group were sectioned at various time points after arsenic exposure. The morphologies and neurogenesis of the neurons in the frontal cortices were observed by hematoxylin-eosin staining, Nissl staining, and doublecortin (DCX) immunostaining. Significant positive correlations between arsenic concentration and deficits in learning and social skills were found, and the arsenic exposure groups showed significant increases in anxiety-like behavior compared with the control group (all Ps ). Abnormal morphologic changes in the external granular layer and external pyramidal layer were positively correlated with the water arsenic concentration in the acute phase of arsenic exposure. However, at five weeks after arsenic exposure, the frontal cortex morphology was restored. Moreover, immunohistochemistry revealed that compared to the control group, the groups that were exposed to arsenic exhibited significantly higher levels of DCX expression in the external granular and external pyramidal layers (all Ps 0.001). Furthermore, the 30 μg/L and 45 μg/L arsenic exposure groups still showed some DCX expression at five weeks after exposure. In conclusion, postnatal low-concentration arsenic exposure impaired learning and social skills and increased anxiety-like behaviors, and abnormal frontal cortex neurogenesis may be the mechanism underlying these effects.

This paper presents an energy management model for electric vehicles (EVs) and thermostatically controlled loads (TCLs) in intelligent energy systems based on the transactive control of aggregators. The management strategy will penetrate through three physical layers of electricity networks: transmission layer, distribution layer, and behind-meter layer. In the proposed framework, the aggregated EVs are modeled as a battery energy storage system (BESS), and the aggregated TCLs are modeled as a virtual energy storage system (VESS) at the behind-meter layer. A deep learning method, namely a hybrid of convolutional neural networks and long short-term memory (CNN-LSTM), is used to forecast the local loads of EVs and TCLs. The aggregators can dispatch these controllable loads directly as demand management to fit the predicted load curve. Peer-to-peer (P2P) trading is realized at the distribution level, and distributed optimization is utilized since the information between each aggregator is opaque. The primal problem is decoupled into subproblems of aggregators. The sub-gradient method is employed to update the multipliers of each decomposed Lagrange function. After the local energy transaction is cleared at the distribution level, wind generators and thermal generators are centrally dispatched at the transmission level based on the conventional optimal power flow model. The proposed hierarchy framework is verified in the IEEE 30-bus system. Simulation results reveal that the scalability issue of single-layer centralized dispatch can be well addressed, and end-users’ information privacy can be protected. The coordinated management of EVs and TCLs also brings in economic and environmental benefits.

This work investigates the adsorption of Cu ions in sediments by conducting batch experiments, including isothermal experiments and adsorption kinetics experiments. Data from isothermal experiments were analyzed using the Langmuir, Freundlich and Temkin models, and the experimental kinetic data were fit using pseudo-first-order, pseudo-second-order, Elovich, liquid film diffusion and intra-particle diffusion models. The Langmuir model resulted in the best fit for the equilibrium data, which indicated that the adsorption capacity of Cu ions on the sediment was 1.0403 mg g −1 with a K L value of 4.2877 L mg −1 . The Freundlich and Temkin models also provided good fits, and the n F and A values were 3.8565 and 66.9964 L mg −1 , respectively, indicating stronger adsorption intensities and adsorption energies between the Cu ions and the sediment. Compared with the pseudo-first-order and Elovich models, the pseudo-second-order model was more appropriate for describing the adsorption kinetics, indicating the chemisorption nature of adsorption. The adsorption kinetic process can be divided into film diffusion, pore diffusion and adsorption reactions. The controlling step for the adsorption kinetics changed with the development of the adsorption process. The entire adsorption process took 180 min. Film diffusion was the controlling step for the first 20 min. During the 20 to 60 min period, the pore diffusion gradually increased and the film diffusion decreased so that both phenomena coexisted. Pore diffusion was the controlling step during the 60–180 min period.

Background: Bilinguals are people that can use two languages for oral communication. Many bilinguals have specific language-associated cortical regions. This study aimed to analyze the cortical positioning features of vocal, semantic, and graphemic task zones in unskilled late Chinese (first)-English (second) (ULCE) bilinguals using the blood-oxygen-level dependent functional magnetic resonance imaging (BOLD-fMRI) technique. Methods: Twelve ULCE bilinguals were assigned Chinese-English (C-E) vocal, semantic, and graphemic tasks; SPM8 software was used to compare and investigate the brain activation maps towards different language tasks and to calculate their corresponding lateralization indexes (LIs). Results: These three language tasks in simple Chinese could activate most traditional language zones, which all exhibited obvious left-deviated activation dominance. A simple English task could also activate most traditional language zones, but only the semantic task appeared to have obvious left-deviated lateralization. However, none of the three tasks displayed any specific language zones between Chinese and English on the group level. Conclusions: Vocal, semantic, and graphemic tasks can all activate multiple brain regions in the language network and reflect their respective cognitive processing characteristics. Bilingual processing in ULCE bilinguals has similar neural mechanisms, but the left-deviated lateralization is not obvious when performing English vocal and graphemic tasks.

Background The mental health and quality of life in children with asthma have attracted widespread attention. This study focused on the evaluation of mental health conditions and their clinical characteristics in Chinese children with asthma. Methods A total of 261 children with asthma aged 6 to 16 years old and 261 age- and gender-matched children from the general population were recruited to participate in this study from Guizhou Provincial People’s Hospital. The parents of all subjects were interviewed using the MINI Kid and were required to finish a clinical characteristics questionnaire. Logistic regression analysis was performed to evaluate risk factors. Results The prevalence of mental health conditions in the asthma group was significantly higher than that in the control group (26.4% vs 14.6%, P ). A total of 10 mental health conditions was identified in the asthma group, the most common of which was ADHD (11.5%; 30/261), followed by oppositional defiant disorder (ODD) (10.7%; 28/261), separation anxiety disorder (6.1%; 16/261), social anxiety disorder (3.8%; 10/261), specific phobias (2.3%; 6/261), agoraphobia without panic (1.5%; 4/261), (mild) manic episodes (1.1%; 3/261), major depressive episodes (MDEs) (0.8%; 2/261), movement (tic) disorder (0.8%; 2/261), and dysthymia (0.4%; 1/261). A total of 6 neuropsychiatric conditions was detected in the control group, including ODD (5.7%; 15/261), ADHD (4.6%; 12/261), social anxiety disorder (3.1%; 8/261), seasonal anxiety disorder (SAD) (2.3%; 6/261), specific phobias (1.1%; 3/261), and agoraphobia without panic (0.4%; 1/261). The prevalence rates of ODD, ADHD, and SAD differed significantly between the two groups (P 3 years (OR = 2.948, 95% CI 1.580–5.502) were independent risk factors for the presence of mental health conditions in asthmatic children. Conclusions Children with asthma have a higher rate of mental health conditions than non-asthmatic children. Standardized diagnosis and treatment may help reduce the risk of neuropsychiatric conditions.

Additional file 1: This file included the “Introduction to the diagnostic sensitivity of the Chinese version of the MINI Kid for different neuropsychiatric diseases” and “The demographics and asthma clinical characteristics questionnaire”.

Urban inundation is a serious challenge that increasingly confronts the residents of many cities, as well as policymakers. Hence, inundation evaluation is becoming increasingly important around the world. This comprehensive assessment involves numerous indices in urban catchments, but the high-dimensional and non-linear relationship between the indices and the risk presents an enormous challenge for accurate evaluation. Therefore, an approach is hereby proposed to qualitatively and quantitatively evaluate inundation risks in urban drainage systems based on a storm water management model, the projection pursuit method, the ordinary kriging method and the K-means clustering method. This approach is tested using a residential district in Guangzhou, China. Seven evaluation indices were selected and twenty rainfall-runoff events were used to calibrate and validate the parameters of the rainfall-runoff model. The inundation risks in the study area drainage system were evaluated under different rainfall scenarios. The following conclusions are reached. (1) The proposed approach, without subjective factors, can identify the main driving factors, i.e., inundation duration, largest water flow and total flood amount in this study area. (2) The inundation risk of each manhole can be qualitatively analyzed and quantitatively calculated. There are 1, 8, 11, 14, 21, and 21 manholes at risk under the return periods of 1-year, 5-years, 10-years, 20-years, 50-years and 100-years, respectively. (3) The areas of levels III, IV and V increase with increasing rainfall return period based on analyzing the inundation risks for a variety of characteristics. (4) The relationships between rainfall intensity and inundation-affected areas are revealed by a logarithmic model. This study proposes a novel and successful approach to assessing risk in urban drainage systems and provides guidance for improving urban drainage systems and inundation preparedness.

Pumped-storage power plant(PSPP) is a special form of power supply. It is expected that the installed capacity of PSPP in China will reach 90GW by 2025. This paper summarizes the development of PSPP in China, and analysis the influencing factors of the configuration of PSPP, introduces the typical operation mode of PSPP and the existing problems in its development, and puts forward relevant policy suggestions for the development of PSPP.

Extreme precipitation occurs frequently because of hydrological variability, resulting in humid cities facing serious waterlogging problems. Previous studies about rainstorms had emphasized on spatial–temporal distribution characteristics, but rarely on rainfall pattern (RP). With a typical humid city in southern China, such as Guangzhou City in Guangdong Province as the research object, hourly precipitation data from January 2009 to October 2014 are collected from five meteorological stations in Guangzhou. The data are counted and classified by fuzzy mode recognition method according to seven typical rainfall patterns (STRP) and the Huff rainfall pattern (Huff RP). Subsequently, the distributive characteristics of urban rainstorm pattern (RSP) are analyzed. The main results obtained are as follows: (1) annual rainstorm days have high positive correlation with rainfall days, and the annual amount of rainstorm contributes to 7.5–50.5% of the annual total rainfall in Guangzhou, (2) large-scale rainfall is highly possible to occur in Guangzhou, (3) most rainstorms in Guangzhou are unimodal, of which the frontal peak is more than 70%, and (4) STRP are appropriate for RSP division in Guangzhou City.

Transport of contaminants with sediment is closely connected with the complex surface morphology of particles in the hydro-environment. Based on a large number of experimental results of sediment morphology, we present the concept of mathematical sand which can address the complex surface morphology of suspended sediment. The sand particle can be represented mathematically by a Fourier series that can simulate the shape and size of real particles. The parameters of Fourier series were determined by around 1036 sediment images obtained by a scanning electron microscopy (SEM). Moreover, the distribution of phosphorus on the surface of a mathematical sand particle was proposed based on the statistical results of measured particle's surface element distribution. The study provided a novel method to explore the relation between the sediment particles and the contaminants.

Water security is an important component of regional security and sustainable development and it significantly affects regional development strategies. Flood security, water resource security, and water environment security are the basic elements of a water security system. These elements exhibit dynamic and complex characteristics. System dynamics (SD) is a qualitative and quantitative simulation and analysis method for system integration. SD is applicable to complex system research and has achieved significant results in water security system research. This study initially collected literature on water security research and application in recent years, and then verified the progress and deficiencies in current research. Our research on water security focuses on managing and predicating a single subsystem. Our research on flood control and disaster mitigation focuses on managing and forecasting floods. Our research on water resource security focuses on water resource management, carrying capacity, and planning, as well as on sustainable water utilization. Finally, our research on water environment security includes water quality management, water pollution control, early warning systems, and water ecology. The SD method can properly solve the complicated relations in a water security system but exhibits limitations in the following aspects: research on large systems; influence of social environment changes; uncertainties in water security; and the methods, means, and influence of natural environment changes on water security.

Sediment particle surface morphology affects phosphorus adsorption. This paper studied the phosphorus adsorption on sediment particle by using a Scanning Electron Microscope (SEM) and an Energy Dispersive X-ray Spectroscopy (EDS). Sediment samples from the Yangtze, Yellow and Yongding rivers in China were chosen to measure the particle surface morphology, surface gray scale and element distribution maps. These samples were firstly cleaned and put into phosphate solution for adsorption. Both the Langmuir equation and Freundlich equation were used for descriptions of adsorption-desorption isotherms for sediments. Particles were then dried and scanned. The results show that the adsorption of phosphorus depends on the surface morphology of particles. Phosphorus exists mostly in the ridges and channels, while a few exist in the slopes, and casually in the peaks, passes and pits.

Most natural sediment particles have numerous pores and a complex surface texture which facilitates their adsorption of contaminants. Particle surface structure, therefore, is an important instrumental factor in the transport of contaminants, especially in water environments. This paper reports on the results of adsorption-desorption experiments to analyze polluted sediment surface pore tension characteristics performed on samples from the bottom of Guanting Reservoir. In our analysis, the Frenkel-Halsey-Hill (FHH) equation is applied to calculate the fractal dimensions of particles to quantify the surface roughness and pore tension characteristics. The results show that the surface fractal dimensions of sediment particle surfaces normally measure from 2.6 to 2.85. The volume of pores smaller than 10 nm changes significantly after being contaminated with pollutants and the fractal dimension decreases because the pores adsorb the contaminants.

The contraction and desensitization induced by albaconol and the influence of capsazepine, capsaicin and extracellular Ca2+ were investigated to see whether the actions were mediated via a specific VR receptor in guinea pig trachea spiral strips in vitro. Both albaconol and capsaicin were contractors of tracheal smooth muscle, but albaconol was not so potent as capsaicin, with -log (M) EC50 values of 4.23 +/- 0.18 (n = 10) and 7.33 +/- 0.21 (n = 10) respectively. 2.5 microM capsazepine competitively antagonized the contractile response to albaconol and capsaicin. Albaconol increased the contraction induced by a low dose of capsaicin (10(-10) to 10(-9) M), but non-competitively antagonized the contraction induced by a high dose of capsaicin (10(-8) to 10(-3) M). Either albaconol (1 or 100 mM) or capsaicin (3 or 10 microM) was able to desensitize the isolated guinea pig bronchi to subsequent addition of albaconol. Capsazepine (5.0 microM) significantly prevented the desensitization induced by either albaconol (1 or 100mM) or capsaicin (3 or 10 microM). Extracellular Ca2+ was essential for albaconol to induce excitation, but it did not affect albaconol- or capsaicin-induced desensitization. In summary, the results from the present study suggest that albaconol induces contraction and desensitization of guinea pig trachea in vitro as a partial agonist for VR.

The effects of plumbagin were investigated on platelet aggregation in vitro and ex vivo, on the binding of thrombin-stimulated platelets to neutrophils, and platelet aggregation induced by intact neutrophils and N-formyl-methionyl-leucyl-phenylalanine (fMLP) or platelet activating factor (PAF) activated neutrophils, by use of the methods of Hamburger, McEver and Born, respectively. The results showed that plumbagin in vitro significantly inhibited adenosine diphosphate (ADP)-, arachidonic acid (AA)-, or platelet activating factor (PAF)-induced platelet aggregation, in a concentration-dependent manner. The medium inhibitory concentrations (IC 50 ) were 39.4, 82.7 and 38.1 microM, respectively. Intragastric plumbagin at 10 mg/kg markedly suppressed platelet aggregation induced by ADP, AA, or PAF. Plumbagin decreased the binding between thrombin-stimulated platelets and neutrophils with an IC 50 of 62.9 microM. Plumbagin significantly inhibited washed platelet aggregation stimulated by fMLP- or PAF-activated neutrophils. The IC 50 values were 54.3 and 47.6 microM, respectively. On the other hand, plumbagin and aspirin increased the inhibition of intact neutrophils on AA-induced platelet aggregation. It is suggested that plumbagin inhibited platelet aggregation in vitro and ex vivo, suppressed the binding of activated platelets to neutrophils, inhibited platelet aggregation induced by activated neutrophils, and increased inhibition of intact neutrophils on platelet reactivity. Abbreviations. DMSO:dimethyl sulphoxide fMLP: N-formyl-methionyl-leucyl-phenylalanine ADP:adenosine diphosphate AA:arachidonic acid PAF:platelet activating factor

Six diterpene alkaloids with an atisine-type C-20-skeleton isolated from the Chinese herbal medicines Spiraea japonica var. acuta and S. japonica var. ovalifolia, as well as eight derivatives of spiramine C and spiradine F were evaluated for the ability to inhibit aggregation of rabbit platelets induced by arachidonic acid, ADP, and platelet-activating factor (PAF) in vitro. The results showed that 12 of the 14 atisine-type diterpene alkaloids significantly inhibited PAF-induced platelet aggregation in a concentration-dependent manner, but had no effect on ADP- or arachidonic acid-induced aggregation, exhibiting a selective inhibition. It is the first report that C-20-diterpene alkaloids inhibit PAF-induced platelet aggregation. However, spiramine C1 concentration-dependently inhibited platelet aggregation induced by PAF, ADP and arachidonic acid with IC50 values of 30.5 +/- 2.7, 56.8 +/- 8.4 and 29.9 +/- 9.9 muM, respectively, suggesting a non-selective antiplatelet aggregation action. The inhibitory effect of spiramine C1 on arachidonic acid was as potent as that of aspirin. Primary studies of the structure-activity relationships for inhibition of PAF-induced aggregation showed that the oxygen substitution at the C-15 position and the presence of an oxazolidine ring in spiramine alkaloids were essential to their antiplatelet aggregation effects. These results suggest that the atisine-type alkaloids isolated from S. japonica are a class of novel antiplatelet aggregation agents. (C) 2002 Elsevier Science B.V All rights reserved.

The cerebroprotective effects of copper aspirinate [dimeric copper(II) bis(o-acetoxybenzoate)] were investigated in gerbils subjected to 10-min global cerebral ischemia followed b 60-min reperfusion. The results showed that intragastric copper aspirinate (7.5, 15.0 and 30.0 mg Kg−1 ) markedly promoted the recovery of the electroencephalogram amplitude, attenuated the increase of lipid peroxide content and the decrease of superoxide dismutase activity in the cortex during ischemia-reperfusion injury. It suggested that copper aspirinate possesses potential neuroprotective properties, the mechanism of which might be related to an increase of the activity of endogenous superoxide dismutase.

Bis(alpha-furancarboxylato)oxovanadium(IV) (BFOV) is a new orally active anti-diabetic organic vanadium complex. In the previous studies, we found that BFOV exhibited a glucose-lowering activity following oral administration to type 1-like diabetic mice induced by alloxan and rats induced by streptozotocin, and the mechanism was not related to enhancing the insulin synthesis and secretion. Since the enhancement of insulin sensitivity is involved in one of the mechanisms by which vanadium exerts its anti-diabetic effects, BFOV has been further tested on fat-fed/streptozotocin-treated rats, a type 2-like diabetic animal model, in the present study. The results showed that 4 weeks of BFOV treatment significantly improved hyperglycemia, glucose intolerance and hyperinsulinemia, as well as increased insulin sensitivity index in the fat-fed/streptozotocin-diabetic rats. Furthermore, BFOV efficiently activated glucokinase, increased hepatic glycogen content and suppressed phosphoenolpyruvate carboxykinase gene expression in the liver and kidney of the diabetic rats, which contributed to augmentation of hepatic glucose disposal and maintenance of blood glucose homeostasis. These findings suggested that BEOV had anti-diabetic and insulin-sensitizing effects in the diabetic rats, exhibiting the potential to be developed as a new therapeutic agent for the treatment of type 2 diabetes.

Spiramine T, an atisine-type diterpene alkaloid isolated from the Chinese herbal medicine Spiraea japonica var. acuta (Rosaceae), was shown to have neuroprotective effects on cerebral ischemia-reperfusion injury. In this study, the effects of spiramine T on antioxidant enzymes and nitric oxide production were evaluated in gerbils subjected to global forebrain ischemia (10 min) and reperfusion (5 days). Spiramine T (1.0 and 2.0 mg kg(-1) i.p.) markedly reduced the content of lipid peroxide (LPO), increased the glutathione peroxidase (GSH-PX) activity, and inhibited the increase of nitric oxidase (NOS) activity and nitric oxide production in the cortex during ischemia-reperfusion in gerbils. These results suggested that the neuroprotective effects of spiramine T were related to modulation of endogenous antioxidant enzymatic activities and reduction of the formation of nitric oxide. (C) 2002 Elsevier Science B.V. All rights reserved.

The neuroprotective effects of spiramine T, an atisine-type diterpenoid alkaloid isolated from the Chinese herbal medicine Spiraea japonica var, acuta (Rosaceaee), on cerebral ischemia-reperfusion injury produced by 10-min bilateral occlusion of the common carotid arteries followed by 5-day reperfusion in gerbils were investigated. Intravenous spiramine T (0.38, 0.75, and 1.5 mg.kg(-1)) markedly reduced the stroke index, enhanced the recovery of EEG amplitude during reperfusion and decreased the concentrations of cortex calcium and LPO in a dose-dependent manner. However, no significant effects on water and sodium contents were observed. These results suggested that spiramine T exhibited protective effects on cerebral ischemia-reperfusion injury in gerbils, and its mechanism might be related to reducing calcium accumulation and lipid peroxidation. This is the first report on spiramine T as a natural product with neuroprotective effects.

Chemical investigation of the basic fraction from the roots of Spiraea japonica var, acuta has resulted in the isolation of three new diterpene alkaloids, spiramines X (1), Y (2) and Z (3), along with five known compounds, spiradine F (4), and spiramines A, B, P (5), and U (6). The structures of 1-3 were determined by spectral and chemical methods. Antiplatelet aggregation activities of compounds (1-6) were tested.

Spiramine Q, a diterpene, was isolated from a Chinese herbal plant Spiraea japonica var. incisa Yu. Born's and Wan HY's methods were used to investigate effects of spiramine Q on rabbit platelet aggregation and serotonin release, respectively. Its antithrombotic effect in mice was also evaluated by Myers' method. Spiramine Q selectively inhibited arachidonic acid-induced platelet aggregation in vitro or ex vivo, and decreased serotonin secretion from rabbit platelets. Spiramine Q (5 mg/kg) decreased the mouse mortality caused by injection of 80 mg/kg arachidonic acid in the tail vein. The results suggested that spiramine Q showed potent antiplatelet and antithrombotic activites.

The efficacy of copper aspirinate against thrombotic diseases has been tested in animal models. The results show that copper aspirinate, following ig pretreatment for 7 days at 0.012mmol/kg markedly prolonged the bleeding time and inhibited the mortality induced by arachidonic acid (AA) in mice. On cereral ischemia model pretreatment with 0.018mmol/kg copper aspirinate ig significantly increased survival of animals and the density of intact hippocampal CA1 cells and decreased brain calcium concentration. Its anticerebral ischemia activity was superior to or equal to nimodipine. It is, therefore, suggested that copper aspirinate is very promising in becoming an antithrombotic drug in preventing and treating thrombotic diseases.

Antitumor activity of the adduct between Carboplatin and α-cyclodextrin has been tested against Sarcoma 180 (S180) and Ehrlich ascites carcinoma (EAC) murine tumors. The preliminary toxicity has also been evaluated by histological examinations of the treated animals. The results show the adduct has less antitumor efficacy than and similar toxicity to Carboplatin.