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Status of study on biological and toxicological effects of nanoscale materials

Science china Chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2 & JIA Guang3.1. Laboratory for Bio-environmental health sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of sciences, beijing 100049, china 2. College of Chemistry and Molecular Engineering, peking university, beijing 100871, china 3. department of occupational and environmental health sciences, school of Public health, peking university,{13. 1. Laboratory for Bio-environmental health sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences 100049 Beijing China 2. College of Chemistry and Molecular Engineering Peking University 100871 Beijing China 3. department of occupational and environmental health sciences School of Public Health Peking University 100083 Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

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Hydroxyl radicals induced by quartz particles in lung alveolar macrophages: the role of surface iron

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Progress in Natural Science:Materials International 2006年第10期16卷 1038-1044页

作者： LI Yi, ZHU Tong, GUO Xinbiao and SHANG Yu ( State Key Joint Laboratory for environmental Simulation & Pollution Control, peking university, beijing 100871, {3. occupational & environmental health sciences, school of Public health, peking university health Science Center, beijing 100083. china) [a]State Key Joint Laboratory for environmental Simulation & Pollution Control Peking University Beijing China [b]occupational & environmental health {3. School of Public Health Peking University Health Science Center Beijing China

Previous studies have shown that hydroxyl radical generation is a key step in the mechanism of pathogenic process caused by airborne particles to the lung. However, there is no direct evidence for dose-response relationship between airborne particles and hydroxyl radical generation. In this study, hydroxyl radicals generated in lung alveolar macrophages exposed to quartz particles were measured using a highly sensitive capillary electrophoresis-fluorescence detection method. The results demonstrated that quartz particles induced the generation of hydroxyl radical in a dose-dependent manner, and the amount of the hydroxyl radicals was 10-10 mol/10 cells. The viability of alveolar macrophages exposed to quartz particles decreased with the increase of quartz concentration, showing a clear dose-response relationship. Hydroxyl radical scavenger mannitol could increase the viability of quartz-treated cells, suggesting that hydroxyl radical contributed directly to cell death. In this study this contribution accounted for about 5%-20% of cell death. The hydroxyl radical generating potential was found to be related to surface iron content of the quartz particles.

关键词： inhalable quartz hydroxyl radical capillary electrophoresis dose-response relationship iron.

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The regular representation and regular covariant representation of crossed products of Woronowicz C^(*)-algebras

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Science china Mathematics 2005年第9期48卷 1245-1259页

作者： ZHANG Xiaoxia~(1,2) & GUO Maozheng~(1,3. 1. school of Mathematical sciences,peking {3.,beijing 100871,china 2. department of Mathematics,Yantai {3.,Yantai 264005,china 3. LMAM,peking {3.,beijing 100871,china 1. school of Mathematical sciences Peking University 100871 Beijing China 2. department of Mathematics Yantai University 264005 Yantai China 3. LMAM Peking University 100871 Beijing China

In this paper,it is shown that the regular representation and regular covariant representation of the crossed products A×α G correspond to the twisted multiplicative unitary operators,where A is a Woronowicz C~*-algebra acted upon by a discrete group ***,it is also shown that the regular covariant C~*-algebra is the Woronowicz C~*-algebra which corresponds to a multiplicative ***,an explicit description of the multiplicative unitary operator for C(SU_q(2) )×α (?) is given in terms of those of the Woronowicz C~*-algebra C(SU_q(2) ) and the discrete group G.

关键词： multiplicative unitary operator, Woronowicz C*-algebra, crossed product.

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The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, china

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Science china Earth sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3. ZHANG Jie2, SONG Linhua1 & BAO Haosheng2 1. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, beijing 100101, {3. 2. department of Geography, Nanjing university, Nanjing 210093. {3. 3. school of Earth sciences and Resources, {3. university of Geosciences, beijing 100083. china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China department of Geography Nanjing University Nanjing 210093 China school of Earth sciences and Resources China University of Geosciences Beijing 100083 China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, china, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (3.) and minor-scale (10-3.10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, china.

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Effects of estrogen on gastrocnemius muscle strain injury and regeneration in female rats

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Acta Pharmacologica Sinica 2004年第11期 105-110页

作者： Xin FENG, Guo-zhen LI, Sheng WANGdepartment of occupational and environmental {3., Public {3. school, peking university {3. Science Center, beijing 100083. china

AIM: To study the effects of estrogen on muscle damage and regeneration after acute passive gastrocnemius muscle strain injury in female Sprague-Dawley rats. METHODS: Rats were divided into 5 groups: ovariectomized, strained and treated with low-dosage estradiol (20 μg/d) (Elow), treated with high-dosage estradiol (200 μg/d) (Ehigh), treated with oil placebo (Oil), strained with no ovariectomy (Strain), and sham operated with no strain and no ovariectomy (Con). Muscle damage index [plasma creatine kinase (CK)], antioxidant indexes [glutathione (GSH), Vitamin E (Vit E), total antioxidant capability (TAC)], and muscle regeneration index (desmin) were investigated at 7 d. RESULTS: The plasma CK activity increased but GSH, Vit E, and TAC levels decreased after muscle strain injury (Strain vs Con P<0.05). Plasma CK activity was the greatest while GSH, Vit E, and TAC were the lowest in the Oil group among the five groups (P<0.01). Plasma CK in the Ehigh and Strain groups was lower than that in the Elow group

关键词： estrogen skeletal muscle muscle injury antioxidant regeneration desmin

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Dehydration melting of solid amphibolite at 2.0 GPa: Effects of time and temperature

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Science china Earth sciences 2005年第8期48卷 1120-1133页

作者： ZHOU Wenge1, XIE Hongsen1, LIU Yonggang1, ZHENG Xiaogang1, ZHAO Zhidan2 & ZHOU Hui3.1. Laboratory of Material in the Earth’s Interior, Institute of Geochemistry, Chinese Academy of sciences, Guiyang 550002, china 2. department of Geology, china university of Geosciences, beijing 100083. china 3. department of Geology, peking university, beijing 100871, china 1. Laboratory of Material in the Earth’s Interior Institute of Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. department of Geology China University of Geosciences 100083 Beijing China 3. department of Geology Peking University 100871 Beijing China

Two sets of dehydration-melting with a natural solid amphibolite, collected from North Himalayan structure zone, Tibet, have been carried out in multi-anvil apparatus at 2.0 GPa and 800―1000℃, for 12―200 h. One is keeping the pressure at 2.0 GPa and the annealing time of 12 h, changing the temperature (800―1000℃). The other is keeping the pressure at 2.0 GPa and temperature at 850℃, varying the annealing time (12―200 h). The products are inspected with microscope and electron probe. The results indicate that at 2.0 GPa, annealing time of 12 h, garnets, melts and clinopyroxenes occur in amphibolite gradually with increasing temperature and the chemical compositions of melt vary from tonalite to granodiorite, and then to tonalite. However, at 2.0 GPa and 850℃, with the annealing time increasing, the garnets, melts and cli-nopyroxenes also occur in amphibolite gradually and the chemical compositions of melt vary from tonalite to granodiorite. In both cases, melts interconnect with each other when the contents of melt are over the 5 vol.%. the viscosities of the melt produced in amphibolite at temperature higher than 850℃ are on a level with 104 Pa·s. The interconnected melt with such a viscosity may segregate from the source rock and form the magma over reasonable geological time. Therefore, it is believed that at the lower part of the overthickened crust, the tonlitic and grano-dioritic magma may be generated through the dehydration melting of amphibolite.

关键词： solid amphibolite, high pressure, high temperature, time, partial melting.

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Some basic concepts and problems on the petrogenesis of intra-plate ocean island basalts

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Chinese Science Bulletin 2009年第22期54卷 4148-4160页

作者： NIU Yaoling1,2,3.1 department of Earth sciences, Durham university, Durham DH1 3.E, UK 2 {3. of Earth sciences and Resources, china university of Geosciences, beijing 100083. china 3.{3. of Earth and Space sciences, peking university, beijing 100871, china department of Earth sciences Durham University Durham DH1 3LE UK school of Earth sciences and Resources China University of Geosciences Beijing 100083 China school of Earth and Space sciences Peking University Beijing 100871 China

Basaltic magmatism that builds intra-plate ocean islands is often considered to be genetically associated with "hotspots" or "mantle plumes". While there have been many discussions on why ocean island basalts (OIB) are geochemically highly enriched as an integral part of the mantle plume hypothesis, our current understanding on the origin of OIB source material remains unsatisfactory, and some prevailing ideas need revision. One of the most popular views states that OIB source material is recycled oceanic crust (ROC). Among many problems with the ROC model, the ocean crust is simply too depleted (e.g., [La/Sm]PM > 1) OIB. Another popular view states that the enriched component of OIB comes from recycled continental crust (RCC, i.e.; terrigenous sediments). While both CC and OIB are enriched in many incompatible elements (e.g., both have [La/Sm]PM >>1), the CC has characteristic enrichment in Pb and deletion in Nb, Ta, P and Ti. Such signature is too strong to be eliminated such that CC is unsuitable as source material for OIB. Plate tectonics and mantle circulation permit the presence of ROC and RCC materials in mantle source regions of basalts, but they must be volumetrically insignificant in contributing to basalt magmatism. The observation that OIB are not only enriched in incompatible elements, but also enriched in the progressively more incompatible elements indicates that the enriched component of OIB is of magmatic origin and most likely associated with low-degree melt metasomatism. H2O and CO2 rich incipient melt may form in the seismic low velocity zone (LVZ). This melt will rise because of buoyancy and concentrate into a melt rich layer atop the LVZ to metasomatize the growing lithosphere, forming the metasomatic vein lithologies. Erupted OIB melts may have three components: (1) fertile OIB source material from depth that is dominant, (2) the melt layer, and (3. assimilation of the metasomatic

关键词：岩石成因论海洋 OIB 矿物学

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Role of inositol 1,4,5-trisphosphate receptors in α1-adrenergic receptorinduced cardiomyocyte hypertrophy

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Acta Pharmacologica Sinica 2006年第7期27卷 895-900页

作者： Da-li LUO~(2,3.5) Jian GAO~2 Xiao-mei LAN~3.Gang WANG~4 Sheng WEI~4 Rui-ping XIAO~4 Qi-de HAN~3. department of Pharmacology,school of Chemical Biology & Pharmaceutical sciences,Capital {3. of Medical sciences,beijing 100069,china 3.Institute of Cardiovascular Science at health Science Center,peking {3. beijing 100083.china 4 Institute of Molecular Medicine and College of Life Science,peking {3.,beijing 100871,china department of Pharmacology School of Chemical Biology & Pharmaceutical Sciences Capital University of Medical Sciences Beijing 100069 China Institute of Cardiovascular Science at health Science Center Peking University Beijing 100083 China Institute of Molecular Medicine and College of Life Science Peking University Beijing 100871 China

Aim:Intracellular Ca2+plays pivotal roles in diverse cellular functions,includinggene transcription that underlies cardiac remodeling during stress ***,the role of inositol 1,4,5-trisphosphate receptors（IP3.s）in the media-tion of cardiac intracellular Ca2+and hypertrophic growth remains *** with neonatal rat ventricular myocytes suggests that activation of IP3.smay be linked to α1adrenergic receptor（α1AR）increased stereotyped Ca2+sparkoccurrence and global Ca2+***,we hypothesized that Ca2+releasethrough IP3.s was necessary for α1AR-stimulated cardiac ***:We used myoinositol 1,4,5-trisphosphate hexakis（butyryloxymethyl）ester（IP3.M）,a membrane-permeant ester of IP3.to activate IP3.s directly,and Fluo 4/AM tomeasure intracellular Ca2+***:IP3.M(10μmol·L-1)mimicked theeffects of phenylephrine,a selective agonist of α1AR,in increments in local Ca2+spark release（especially in the perinuclear area）and global Ca2+*** importantly,IP3. inhibitors,2-aminoethoxydiphenyl borateand Xestospongin C,abolished the IP3.M-induced Ca2+responses,and signifi-cantly suppressed α1AR-induced cardiomyocyte hypertrophy assayed by cellsize,[3.]leucine incorporation and atrial natriuretic factor gene expression,dur-ing sustained（48 h）phenylephrine ***:These results,therefore,provide cellular mechanisms that link IP3. signaling to α1AR-stimulatedgene expression and cardiomyocyte hypertrophy.

关键词： inositol 1,4,5-trisphosphate receptors Ca2+sparks α1 adrenergic stimulation cardiac hypertrophy

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Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central china: Constraints from geochemistry and melt inclusions

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Science china Earth sciences 2005年第8期48卷 1146-1157页

作者： SU Li1,2, SONG Shuguang3.& ZHOU Dingwu1 1. Key Laboratory of Continental Dynamics of the Ministry of Education, department of Geology, Northwestern university, Xi’an 710069, china 2. The Geological Lab Center, china university of Geosciences (beijing), beijing 100083. china 3. Key Laboratory of Orogenic Belts of the Ministry of Education, department of Geology, peking university, beijing 100871, china 1. Key Laboratory of Continental Dynamics of the Ministry of Education Department of Geology Northwestern University 710069 Xi’an China 2. The Geological Lab Center China University of Geosciences 100083 (Beijing)Beijing China 3. Key Laboratory of Orogenic Belts of the Ministry of Education Department of Geology Peking University 100871 Beijing China

The Songshugou dunite body, which occupies an area of about 20 km2, is the largest ultramafic massif in the eastern Qinling orogenic belt, Central china. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2O3. CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

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Antitumor and anti-angiogenic activity of Ganoderma lucidum polysaccharides peptide

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Acta Pharmacologica Sinica 2004年第6期25卷 131-136页

作者： Qi-zhen CAO, Zhi-bin LIN1 department of Pharmacology, health Science Center, peking university,{3. department of Pharmacology Health Science Center Peking University

AIM: To investigate the antitumor and anti-angiogenic activity of Ganoderma lucidum polysaccharides peptide (GLPP). METHODS: Antitumor effect of GLPP was observed in tumor-bearing mice in vivo. At the same time, the effects of GLPP on proliferation of tumor cells and human umbilical cord vascular endothelial cell (HUVEC) were detected by MTTassay in vitro. Subsequently, spleen lymphocytes proliferation of nude mice was stimulated by LPS or ConA. To investigate the anti-angiogenic effect of GLPP, GLPP 80 μg per disc and GLPP-treated serum 10 μL per disc were added to the chick chorioallantoic membrane (CAM) respectively in vivo. RESULTS: GLPP 50, 100, and 200 mg/kg inhibited growth of Sarcoma 180 in BALB/c mice markedly by 3..2 %, 45.2 %, and 61.9 %, respectively. GLPP which was directly added to the cultured medium did not inhibit PG cell proliferation in vitro; but GLPP-treated serum 50, 100, 200 mg/kg potently inhibited PG cell proliferation by 22.5 %, 26.8 %, and 3..3.%, respectively; and reduced the xenograft (human lung carcinoma cell PG) in BALB/c nude mice greatly in vivo by 55.5 %, 46.0 %, and 46.8 %, respectively. Lymphocytes proliferation of nude mice could be stimulated by LPS 5 mg/Lbut not by ConA 2.5 mg/L, indicating that GLPP could not promote the T lymphocyte proliferation and neutral red phagocytosis of peritoneal macrophages of nude mice. The CAM assay showed that GLPP and GLPP-treated serum had anti-angiogenic effect. GLPP (1, 10, and 100 mg/L) inhibited HUVEC proliferation in vitro with the inhibitory rate of 9.4 %, 15.6 %, and 40.4 %, respectively. CONCLUSION: GLPP has antitumor and anti- angiogenic activity. The anti-angiogenesis of GLPP may be a new mechanism underlying its anti-tumor effects.

关键词： Ganoderma lucidum polysaccharides sarcoma 180 adenocarcinoma lung neoplasms lympho- cyte proliferation peritoneal macrophages angiogenesis nude mice

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