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Nitrated polycyclic aromatic hydrocarbons (NPAHs) are a family of toxicants wide spreading in the environment. In this study, quantitative structural-activity relationship (QSAR) models were developed for the prediction of mutagenicity of NPAHs. Structural descriptors were screened and multiple linear regression (MLR) were performed for developing the QSAR models. Totally 1706 descriptors were obtained based on structural optimization using density functional theory (DFT) at the CPCM-B3LYP/6-311+g (d,p) theoretical level in water. External and leave-one-out cross validation were performed to confirm the predictive ability and the models robustness, respectively. Totally 33 QSAR models were generated using one to eight descriptors, in which the model consisting of 4 descriptors, including Eelec, SIC2, RDF040v and GATS4v, has the highest correlation coefficient (R2=0.8755). This study will contribute to not only the prediction of the mutagenicity of NPAHs, but also the development of QSAR modeling methods of toxicants.

Rural revitalization strategy, precise poverty alleviation, and priority poverty alleviation in the destitute areas, are the three important new problems in rural poverty alleviation and the “three rural” work in recent years in China. Intellectual precision poverty alleviation , is not only the precise poverty alleviation based on the development of intellectual resources and the protection of agricultural intellectual property, but also the knowledge economy way to the rural revitalization strategy in poor areas. The Wuling mountain area is the national demonstration area of priority poverty alleviation, and one of China's important areas of tea producing. This paper analyzed the strategy of the protection of agriculture intellectual property rights of tea industry and intellectual precision poverty alleviation in this area, proposed several suggestions under the rural revitalization strategy, such as: to implement the intellectual property strategy of regions and leading enterprises; to develop agricultural intellectualization and knowledge economy; to inherit the traditional knowledge and cultural heritage; to implement standardization and agricultural industrialization; to construct the regional scientific and technological innovation system; to promote competitiveness and self-generating ability; to establish the geographical indication pillar industry of the regional characteristics; to dock the Belt and Road strategy; to implement regional brand strategy; to develop agricultural and rural informatization; to promote the “internet plus agriculture” intelligence precise poverty alleviation, etc. The paper stated the definition and basic idea of intellectual precision poverty alleviation.

Priority poverty alleviation in the destitute areas, precise poverty alleviation, and rural revitalization strategy, are the three important new problems in rural poverty alleviation and the “three rural” work in recent years in China. “The world's selenium capital” Enshi city is located in the Wuling mountain area, which is one of the main battlefields of the rural poverty alleviation in China, which has the characteristics of Se-rich industry and animal husbandry. This paper describes the selenium resources, animal husbandry industry, animal husbandry resources, national poverty villages and so on in the city. From the perspectives of industrialization, informatization, intellectualization and development of intellectual animal husbandry and knowledge economy, this paper studies the development and utilization of the intellectual resources in the animal husbandry and the strategy of intellectual precision poverty alleviation based on “internet + Se-rich animal husbandry” in Enshi. A few suggestions are put forward under the rural revitalization strategy.

Rural revitalization strategy, precise poverty alleviation and priority poverty alleviation in the destitute areas, are the three important new problems in the “three rural” work and rural poverty alleviation in recent years in China. Wufeng tujia autonomous county, Changyang tujia autonomous county, Zigui county in Yichang city, are located in the “main battlefield” of the national poverty alleviation — the Wuling mountain area. This paper introduces the agricultural intellectual property rights of the three counties' patents related to agriculture, trademarks, geographical indications, agricultural biological genetic resources, traditional knowledge, and new plant varieties. Based on the perspective of traditional knowledge, the paper analyzes the rural revitalization strategy and intellectual precision poverty alleviation, and puts forward ten suggestions.

Priority poverty alleviation in the destitute areas and precise poverty alleviation, are the two important new problems in rural poverty alleviation and the “three rural” work in recent years in China. Lichuan city has 50 national poverty villages, is located in the “main battlefield” of the national poverty alleviation—the Wuling mountain area. This paper introduces the agricultural intellectual property rights of the city's geographical indications, agricultural biological genetic resources, traditional knowledge, trademarks, patents related to agriculture and new plant varieties, analyzes the strategies of agricultural intellectual property protection and intelligent precision poverty alleviation under the rural revitalization strategy, and puts forward some suggestions.

Dispersion of nanoalumina in normal saline (NS) and phosphate buffered saline (PBS) was studied. The effects of different dispersing methods were investigated. The results showed nanoalumina was better dispersed in NS than PBS. And sonication was a more effective method that helped deaggregation compared with vortex oscillation. Finally, the influence of sonication time on the particle size and the stability of the sonicated NS suspension were studied using dynamic light scattering. The aggregation size was decreased to about 130 nm after ten-minute sonication and maintained when increasing sonication time. The particles would aggregate again during the storing time. The results of this study need to be taken into account prior to dosing in nanoalumina toxicology studies.

Objective: Skin damage induced by ischemia/reperfusion (I/R) is a multifactorial process that often occurs in plastic surgery. The mechanisms of I/R injury include hypoxia, inflammation, and oxidative damage. Hydrogen gas has been reported to alleviate cerebral I/R injury by acting as a free radical scavenger. Here, we assessed the protective effect of hydrogen-rich saline (HRS) on skin flap I/R injury. Methods: Abdominal skin flaps of rats were elevated and ischemia was induced for 3 h; subsequently, HRS or physiological saline was administered intraperitoneally 10 min before reperfusion. On postoperative Day 5, flap survival, blood perfusion, the accumulation of reactive oxygen species (ROS), and levels of cytokines were evaluated. Histological examinations were performed to assess inflammatory cell infiltration. Results: Skin flap survival and blood flow perfusion were improved by HRS relative to the controls. The production of malondialdehyde (MDA), an indicator of lipid peroxidation, was markedly reduced. A multiplex cytokine assay revealed that HRS reduced the elevation in the levels of inflammatory cytokines, chemokines and growth factors, with the exception of RANTES (regulated on activation, normal T-cell expressed and secreted) growth factor. HRS treatment also reduced inflammatory cell infiltration induced by I/R injury. Conclusions: Our findings suggest that HRS mitigates I/R injury by decreasing inflammation and, therefore, has the potential for application as a therapy for improving skin flap survival.

In this study, we discussed an efficient approach for the synthesis of camphorquinone from camphor by the continuous reaction of bromination and oxidation. The oxidation of 3-bromocamphor was catalyzed by Fe-porphyrins with air. The catalytic activity of iron-metallated functional porphyrins was investigated under optimization conditions. The results showed that this method was a milder alternative to the reported methods, with a simple, greener procedure in which the advantages were the utilization of air as the oxidant and the use of metalloporphyrins as catalysts.

The relationship between carcinogenicity and DNA interstrand cross-links of nitrosoureas is poorly defined. 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3- (2-chloroethyl)- 3- nitrosourea (ACNU, nimustine) is one of nitrosoureas used in the treatment of high-grade gliomas. It has the capability of causing DNA interstrand cross-links (ICLs) to kill cancer cells. But it can also cause the generation of secondary tumors with carcinogenic side effects. In present study, we investigated DNA interstrand cross-links, DNA double-strand breaks and cell cycle phase in NIH/3T3 cells from the primary mouse embryonic fibroblast cells induced by ACNU. This result indicated that the concentration of 60 and 75μg/ml of ACNU could be detected significantly ICLs, and the γ-H2AX has the ability to be a biomarker for DNA damage associated with ICLs induced by ACNU. The subgroup of nitrosoureas (CNUs) including 1-(4-amino -2-methyl-5- pyrimidinyl) methyl-3 -(2- chloroethyl) -3- nitrosourea (ACNU, nimustine), 1,3- Bis(2- chloroethyl)- 1- nitrosourea (BCNU, carmustine), 1-(2- chloroethyl)- 3- cyclohexyl- nitrosourea (CCNU, lomustine)

This study was conducted to investigate the efficiency of TiO2 photocatalytic nanomaterial as a novel environment-friendly disinfectant to control plant fungal diseases (Sphaerothecaf uliginea) by its photochemical sterilization ability in cucumber plants. Anatase nano-TiO2 sol, a neutral, viscous aqueous colloid of 1.4% TiO2, was synthesized by sol-gel method. Control efficiencies of nano-TiO2 sol in preventing from powdery mildew were measured by field experimental method with cucumber seedling naturally infected Sphaerothecaf uliginea. Results showed that spraying certain content of nano-TiO2 sol could form continuous and stable antibacterial films on blade surfaces which could not only significantly reduce lesion areas, disease incidences and disease indexes of powdery mildew but also make the leaves turn much greener. It was initially confirmed that nano-TiO2 sol could effectively delay and inhibit the development and pervasion of cucumber powdery mildew. These results indicate that nano-TiO2 sol can be developed as environment-friendly fungicide in preventing from plant disease developments.

The 4-aryl-1,4-dihydropyrazines were prepared via the cyclization of N,N-bisalkylated anilines with ammonium acetate. These reactions were aided by improvements in the synthesis of N,N-bisalkylated anilines which were alkylated with anilines using ethyl 2-diazo acetoacetate in a reaction catalyzed by rhodium acetate in the absence of oxygen. A possible mechanistic route is postulated on the basis of the isolation of the N-alkylation intermediates, which were determined to be N-aryloxamates by 1H NMR data and X-ray diffraction.

Phytoremediation is the use of vegetation for in situ treatment of contaminated soils, sediments, and water. It is best applied at sites with shallow contamination of metal pollutants. The term “assisted phytoextraction” usually refers to the process of applying a chemical additive to contaminated soil in order to increase the metal uptake by crop plants. In the process of phytoremediation, applying plant growth regulator can promote phytoextraction effects. This paper reviewed the effect of the plant growth regulator for the biological growth, plant transpiration and heavy metal stress. the increase in metal accumulation in upper parts of plant could be related to both the role of PGRs in the enhancement of plant resistance to stress (as toxic metals) and the increase in transpiration rate, i.e. flux of water-soluble soil components and contaminants by the regulation of stomatal opening.

Transpiration of plants has an important role in heavy metal absorption. When the transpiration is flourishing, plants accumulate more heavy metals, and its enrichment capability is also stronger.This article reviews the effect of the plant transpiration on hyperaccumulators of heavy metal uptake to lay a solid foundation for further research.

Tetraethyl 2,4,8,10-tetramethyl-6,12-bis(4-fluorophenyl)-3,9-dioxapentacyclo[6.4.0.0 2,7 .0 4,11 .0 5,10 ]dodecane-1,5,7,11-tetracarboxylate ( 1 , simplified as 6,12-bis(4-fluorophenyl)-3,9-dioxatetraasterane) was synthesized by [2 + 2] photocyclization of diethyl 2,6-dimethyl-4-(4-fluorophenyl)-4H-pyran-3,5-dicarboxylate ( 2 ) in solution. The NMR analysis of 1 is discussed in detail by the splittings and assignments of signals according to the three-dimensional structure. Single-crystal X-ray diffraction shows that 1 is situated on an inversion center. The molecular symmetry is close to C 2 h except for the terminal ethyl groups.

Copper(I)-catalyzed terminal alkyne-azide 1,3-cycloaddition reaction has emerged as one of the main strategies for the rapid creation and screening of a small molecular library. The present work describes the design and synthesis of a series of 1,2,3-triazol-4-yl-substituted 1,4-dihydro-4-oxo-1,5-napthyridine-3-carboxylic acids in which the hydrophobic and hydrophilic domains were efficiently incorporated by a click reaction. The structures of the desired products 8 and 12 were characterized by spectroscopic methods and their HIV integrase inhibitory activities were also screened.

Electrochemical synthesis of o -benzoquinone derivatives and their in situ transformation are one of the versatile approaches for the synthesis of derivatized catechols. In the present work, electrochemical oxidation of catechols 1a – 1d in the presence of a unique nucleophile, 4-amino-3-methyl-5-mercapto-1,2,4-triazole 3 , bearing two nucleophilic groups (–NH 2 and –SH), have been studied in phosphate buffer solutions using cyclic voltammetry and controlled-potential electrolysis (CPE) methods. The results show that only the mercapto group participated selectively in the Michael addition reaction and led to the formation of catechol substituted products of types 4 and 5 , bearing a free amino group, potentially useful for further chemical modifications, e.g. of interest in biomedical applications. Various electrolytic conditions, such as the nature of anode material, amount of passed charge, pH of the electrolytic solution and cell configuration (divided or undivided cell), were also investigated to optimize the yields of corresponding products.

Polyhydroxylated aromatic pyrimidinyl thioethers are important compounds due to their potential anti-HIV integrase activity. The present work describes an electrochemical synthetic strategy and environmentally benign approach for the synthesis of these compounds, superior to conventional chemical reactions. Thus, the electrochemical oxidation of 4-substituted catechols and caffeic acid, in the presence of 2-mercaptopyrimidine derivatives 2 , generates monopyrimidinylthio-substituted polyhydroxylated aromatics 3a – f in moderate yields. In the case of catechol itself and 3-substituted catechols, both mono- ( 3g – l ) and dipyrimidinylthio-substituted derivatives ( 4g – l ) were produced. Apparently, the anodic oxidation of catechol derivatives leads to nucleophilic addition products of types 3 and 4 , which are different from the traditional nucleophilic substitution reaction of aryl halides and thiols. The electrochemically induced reaction mechanism is also discussed.

The electrochemical synthesis of 5-purin-6′-ylthiocatechols was carried out by anodic oxidation of catechol derivatives 1a–1d in the presence of 6-mercaptopurine (2) in aqueous solution. Results of cyclic voltammetry and controlled-potential electrolysis indicated that the starting catechols were first oxidized to the corresponding o-benzoquinone, which underwent further Michael addition with 6-mercaptopurine to produce titled products 3a–3d following an EC (E=electrochemical and C=chemical step) mechanism. Such work further demonstrates the versatility of the anodic oxidation of catechols and their in-situ transformation for the synthesis of derivatized catechols.

The anodic oxidation of caffeic acid in the presence of sodium benzenesulfinate in aqueous solution was studied by cyclic voltammetry and controlled potential coulometry. The results showed that similar to other simple catechol derivatives where the substituents attached directly to the benzene ring, caffeic acid was oxidized to the corresponding o-benzoquinone which underwent further Michael-addition with sodium benzenesulfinate or sodium p-methyl benzenesulfinate to produce 6-arylsulfonyl caffeic acid derivative 7a or 7b.

Diketo acid derivatives are potent and selective HIV-1 integrase inhibitors. To investigate the detailed synthesis of those derivatives, a series of p/m-[p-(un)substituted phenylsulfonamido]phenyl β-diketo acid derivatives have been designed and synthesized. The quinoxalone derivatives as the potential bioisosteres of the biologically labile β-diketoacid pharmacophores have also been synthesized from reactions of the corresponding diketo acids with o-phenylenediamine. The structures of all diketo acid (ester) and quinoxalone derivatives were confirmed by 1H NMR, 13C NMR, IR, HRMS and/or MS (ESI). X-ray crystallographic analysis of 11b demonstrates a similar arrangement of the side chain of quinoxalone derivatives with the parent diketoacids due to the intramolecular hydrogen bond (O···H–N) and the sp2 hybridization configuration of the two nitrogen atoms of the quinoxalone ring.

3-[2-Oxo-2-(4-methyloxyphenylsulfonamidophenyl)ethylidene]-3,4-dihydro-1H-quinox-alin-2-one (4) was synthesized and characterized by 1H NMR,13C NMR, IR, and single-crystal X-ray diffraction techniques. The crystallographic results show that the composition of the title compound is C23H19N3O5S. It belongs to triclinic crystal system and P-1 space group, with a=7.273(6) A, b=9.092(7) A, c=15.928(13) A; α=85.135(11)°, β=78.297(10)°, γ=84.619(11)°, V=1024.4(14) A3, Z=2, D c=1.457 mg/m3, μ = 0.201 mm−1, F(000)=468, R=0.0597, wR=0.1438.

The reactivity of N -phosphoryl f -alanine differs from N -phosphoryl g -alanine and N -phosphoryl n -amino butyric acid enormously. N -phospho- f -alanine could self-activate to yield N -phosphopeptides either in aqueous or nonaqueous media, but not g - or n -amino acid analogues. The mechanism of the reaction is discussed.

In recent years β-amino acids have increased their importance enormously in defining secondary structures of β-peptides. Interest in β-amino acids raises the question: Why and how did nature choose α-amino acids for the central role in life? In this article we present experimental results of MS and 31P NMR methods on the chemical behavior of N-phosphorylated α-alanine, β-alanine, and γ-amino butyric acid in different solvents. N-Phosphoryl α-alanine can self-assemble to N-phosphopeptides either in water or in organic solvents, while no assembly was observed for β- or γ-amino acids. An intramolecular carboxylic–phosphoric mixed anhydride (IMCPA) is the key structure responsible for their chemical behaviors. Relative energies and solvent effects of three isomers of IMCPA derived from α-alanine (2a–c), with five-membered ring, and five isomers of IMCPA derived from β-alanine (4a–e), with six-membered ring, were calculated with density functional theory at the B3LYP/6-31G** level. The lower relative energy (3.2 kcal/mol in water) of 2b and lower energy barrier for its formation (16.7 kcal/mol in water) are responsible for the peptide formation from N-phosphoryl α-alanine. Both experimental and theoretical studies indicate that the structural difference among α-, β-, and γ-amino acids can be recognized by formation of IMCPA after N-phosphorylation. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem 94: 232–241, 2003

The anodic oxidation of caffeic acid in the presence of acetylacetone or methyl acetoacetate in aqueous solution has been studied by cyclic voltammetry and controlled-potential electrolysis techniques. The result showed that caffeic acid was oxidized to the corresponding o -benzoquinone, which underwent further Michael-addition with acetylacetone or methyl acetoacetate to produce caffeic acid derivative 3,4-dihydroxy-6-(1-acetylacetone)-yl cinnamic acid 4a or 3,4-dihydroxy-6-(1-acetyl-methylacetate)-yl cinnamic acid 4b .

The reaction of monocyclic oxyphosphorane compounds 1a, 1b, 1c, with ethylene glycol in pyridine was studied by 31P NMR. The results showed that compound 1a, with an unsaturated five-membered ring reacts slightly faster than compound lb with a saturated ring attached by two trans p-nitro phenyl groups, which reacts 100 times faster than the cis compound lc. To interpret the mechanism, hexacoordinated intermediates 3, and 4, were proposed. The properties of 3b, and 3c, as well as 1b, and 1c, were investigated on the basis of PM3 calculations. The calculations showed that there was about 2.9 kcal/mol difference between the active energy of the ester exchange reaction for compound 1b, and 1c, which matched well with our experimental results and provided more support to the proposed mechanism.

The title compound, C23H19N3O4S, a quinoxalone derivative, is the product of the condensation reaction of 4-[4-(4-methyl­phenyl­sulfonamido)phen­yl]-2,4-dioxobutanoic acid with o-phenyl­enediamine. Inter­molecular N—H⋯O hydrogen bonds and π–π stacking inter­actions stabilize the solid structure.

The title compounds (IV) are formed via cyclization of N,N-bisalkylated aniline derivatives (III) with ammonium acetate.

To predict the carcinogenicity of polycyclic aromatic hydrocarbons (PAHs) by cell transformation assay using BALB/c 3T3 cells and HPV16-E6E7-transfected BALB/c 3T3 cells (BALB/c-E6E7 cells).The cell transformation assays induced by PAHs using BALB-E6E7 cells and BALB/c 3T3 cells.The initiating and promoting activities of PAHs examined in a BALB-E6E7 cell transformation assay were similar to in a BALB/c 3T3 cell transformation assay, which was up to the standard of agents classified by the IARC. There were much more transformed foci appeared and much shorter time consumed to accomplish phenotypic alterations in the BALB/c-E6E7 cell transformation assay than in the BALB/c 3T3 cell transformation assay. The BALB/c-E6E7 cell transformation assay was superior to the BALB/c 3T3 cell transformation assay in cost and labor performance, the sensitivity of transformation response.The BALB/c-E6E7 cell transformation assay, with a satisfied prediction performance of initiating activity and promoting activity, would improve the overall process of safety and risk assessment of carcinogenicity.

Comparison investigations were performed for the enrichment method of lead in environmental waters, including coprecipitation, ion exchange and cloud point extraction (CPE). CPE was selected as the optimal enrichment method because of its less consumption of water sample, higher enrichment factor and simpler procedure than the other enrichment methods. Pb contents in the water samples from Tonghui River in Beijing were determined by high resolution continuum source graphite furnace atomic absorption spectrometry coupled with CPE enrichment. The results indicate that the limit of detection of the method is 0.08 microg x L(-1), the relative standard deviation (RSD) is 1.3% to 4.5% (n = 6), the recovery of Pb contents is 93% to 108%, and the enrichment factor of CPE method is 29. The Pb contents in the 13 water samples from Tonghui River all conform to the Environmental Quality Standards for Surface Water (Grade I). Moreover, the Pb content in the whole river exhibits a decreasing trend from Tongzhou district to Chaoyang district.

The contents of lead, cadmium and chromium were determined for 22 kinds of foods including cereals, vegetables, beverage, sea foods and dairy products by using high resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GFAAS). The methods for sample preparation, digestion, and quantitative analysis were established, by which satisfying analytical precision (RSD = 1.3%-4.9%) and recovery (95.1%-104.6%) were achieved. The results indicated that the contents of lead in tea leaves and chromium in shellfish were much higher than those in the other foods; the contents of cadmium in millet, leek and shellfish were relatively higher than the others. This work established reliable methods for quantitative analysis of heavy metals in foods, which provided experimental references for the constitution of food quality and safety standards. Meanwhile, the distributions of heavy metals in foods given by this work can be expected to enhance the consumers' consciousness of food safety.

Raman spectroscopy is an analytical techniques based on Raman scattering, which gives information of molecular vibration and rotation. Raman spectroscopy has been widely employed in the investigations of the structure of biomolacules, because it has many advantages over the common chemical analysis. Raman spectroscopy is non-destructive to the samples. Moreover, it requires simple sample preparation and small sample amount. Raman spectroscopy can be used not only for fast detections of damages of biological macromolecules, such as proteins, nucleic acids and lipids, but also for diagnosis and surgical treatments of cancer. By comparing the Raman spectra of normal tissue and cancer tissue, the differences in the characteristic absorption peaks between the two kinds of tissues can be confirmed, which provides significant information for final diagnosis of cancer and determination of the resection extent of tumor. This paper reviewed the researches on biomolecular damages by Raman spectral inspections. It described the applications of Raman spectral techniques, such as surface-enhanced Raman spectroscopy, Fourier transform Raman and UV resonance Raman spectroscopy, in the detection of protein secondary structures, membrane lipids and DNA damages. A prospect of the development of Raman spectroscopy in the future was given.

Exposure to lead causes a number of diseases, including mild mental retardation resulting from loss of IQ points, as well as increased blood pressure, gastrointestinal effects. Several other disease outcomes have been associated with exposure to lead, but evidence is considered insufficient at this time for a quantitative assessment of their impact on health to be made here. Lead, due to its multiplicity of uses (e.g. leaded petrol, lead in paints, ceramics, food cans, make-up, traditional remedies, batteries), is present in air, dust, soil and water to varying degrees. Each of these media can act as a route of human exposure, through ingestion or inhalation and, to a small degree for organic lead compounds, dermal absorption. Human exposure can be assessed directly, through body burden measurements (lead in blood, teeth or bone) or indirectly, by measuring levels of lead in the environment (air, dust, food or water).

Exposure to lead causes a number of diseases, including mild mental retardation resulting from loss of IQ points, as well as increased blood pressure, gastrointestinal effects. Several other disease outcomes have been associated with exposure to lead, but evidence is considered insufficient at this time for a quantitative assessment of their impact on health to be made here. Lead, due to its multiplicity of uses (e.g. leaded petrol, lead in paints, ceramics, food cans, make-up, traditional remedies, batteries), is present in air, dust, soil and water to varying degrees. Each of these media can act as a route of human exposure, through ingestion or inhalation and, to a small degree for organic lead compounds, dermal absorption. Human exposure can be assessed directly, through body burden measurements (lead in blood, teeth or bone) or indirectly, by measuring levels of lead in the environment (air, dust, food or water).

New method for rapid and quantitative analysis of 6-benzylaminopurine (6-BA) residues in sprout beans was studied by using FAST-SPE and portable surface-enhanced Raman spectroscopy (SERS). With homemade sprout bean samples as blank control, 6-BA solutions extracted from inserted-treatment samples showed typical characteristic Raman peaks at 1002 cm(-1) tested by SERS, and normalized 1002 cm(-1) intensities had a good linear relationship with gradient concentrations of 6-BA insert-standard solutions. The high concentration linear range was 0.5-14 microg x mL(-1), and the low one was 0. 1-2 microg x mL(-1). The quantitative detection limit was down to 0.02 mg x kg(-1) that was below the maximum allowable residues (MAL) of 0. 2 mg kg(-1) in related National Standard. The recoveries were 82.3%-95.1% and the RSD was below 5%. This method with portable equipment and simple pre-treatment showed good reproducibility, short test time-consuming and easy operating, and thus it would provide efficient and sensitive solutions for large-scale on-site and rapid detections.

Infrared spectroscopy (IR) is employed as an important tool in the investigation of biological macromolecules because of its high sensitivity and nondestructivity to samples. When proteins, lipids or nucleic acids are damaged, the position, shape and intensity of their IR characteristic absorption peaks will be significantly changed. This provides evidences for the determination of the damages of biomolecules, which further shed light on the clarification of the occurrence, development and early prevention of some diseases. In the present paper, the applications of IR to the detection of biomolecular damages are reviewed. Various IR techniques are introduced, including Fourier transform infrared spectroscopy (FTIR), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), Fourier transform infrared spectroscopy microscope and so on. A general review was performed for the application of IR technique to the qualitative and quantitative analysis of secondary structure of protein, fluidity of membrane lipid, interaction of drugs with DNA and so on. The existing problems of IR were pointed out and the prospect of IR technique in the field of biomedicine was discussed. It is expected that, in the future the researches involving IR techniques will be focused on the application in early diagnosis of diseases, instrumental combinations and quantitative techniques.

The contents of aluminum (Al) in four kinds of wheat flour food (noodle, dumpling wrapper, twisted cruller and soda biscuit) were determined by high resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GFAAS) combined with microwave digestion. The samples were completely digested by the mixture of HNO3 and H2O2 in closed polytetrafluoroethylene (PTFE) vessels. The conditions for microwave digestion, pyrolysis temperature and atomization temperature were optimized. The optimum experimental conditions were determined as follows. The microwave digestion was performed with HNO3/H2O2 7:1 (volume ratio), microwave power 1000 W and 190 degrees C for 40 minutes. The optimum pyrolysis temperature was 1350 degrees C and the optimum atomization temperature was 2400 degrees C. Magnesium nitrate solution with the concentration of 1 g x L(-1) was used as the matrix modifier. The correlation coefficient for the standard curve was 0.9999, the relative standard deviation (RSD) was from 1.7% to 2.4%, and the recovery for the samples was from 98.16% to 102.67%. The assay method for the determination of Al in wheat flour food established in this study has referential importance for the constituent of the correlated food standards.

To explore the antineoplastic effect in vitro of earthworm coelomic fluid (ECF)on growth inhibition and its mechanism for the tumor cell lines Siha, SW480, Colo205 and PC12.MTT colorimetric assay, flow cytometry and morphological analysis were used to test its antitumor activity on tumor cell lines and normal cell line Cos7 in vitro.ECF can inhibit the cell growth of Siha, SW480, Colo205, PC12 and Cos7. But different tumor cell lines showed different sensitivity.EFC can significantly inhibit the proliferation of tumor cells in vitro by inducing tumor cells apoptosis.

To optimize a pretreatment method of urine proteomics in children with primary nephrotic syndrome.Urine from children with primary nephrotic syndrome was treated in different pH and isolated by cold acetone precipitation for different durations. Then the amounts and kinds of proteins were compared by quantify, SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and two-dimensional electrophoresis (2-DE) in order to optimize a way to deal with urine protein.Most proteins were obtained at pH 2.7. The amounts of protein precipitated by acetone for 0.5 hr was obviously less than those precipitated for 1 and 2 hrs (P0.05), while there was no significant difference between the amount of protein precipitated for 1 and for 2 hrs. Protein precipitated by cold acetone for 1 hr at pH 2.7 was selected as the best pretreatment method. Satisfactory 2-DE maps can be acquired.Urine protein can be best obtained at pH 2.7 and precipitated by cold acetone for 1 hr.

A general and cost-effective method for the environmentally friendly oxidation of bromomethyl-substituted pyridine, quinoline and phenanthroline derivatives to the corresponding carboxylic acids is developed using less toxic Ph-I(O-Ac)2 and biologically relevant iron(III)porphyrins as catalysts.

To explore the antivirus function in vitro of earthworm coelomic fluid (ECF) by researching its effect on inhibiting respiratory syncytial virus (RSV).By the method of Hep-2 cell culture and using ribavirin as a positive control, the anti-RSV effect of ECF was investigated by observing cytopathic effect (CPE) with MTT colorimetric assay.In Hep-2 cells, the CC50 of ECF and ribavirin were 3.11 mg/ml and 1.35 mg/ml separately. In the experiment of ECF directly killing RSV, the IC50 of ECF was 184.1 microg/ml, SI was 16.87; In the experiment of ECF preventing RSV invasion, no antiviral function of ECF within the experimental concentration range was observed; In the experiment of ECF inhibiting RSV replication, the IC50 of ECF was 1555. 8 microg/ml, SI was 1.99.ECF couldn't prevent virus from invading into host cell, but showed direct killing-virus function and inhibition of the virus replication.