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Asparagus officinalis is an economically and nutritionally important vegetable crop that is widely cultivated and is used as a model dioecious species to study plant sex determination and sex chromosome evolution. To improve our understanding of its genome composition, especially with respect to transposable elements (TEs), which make up the majority of the genome, we performed Illumina HiSeq2000 sequencing of both male and female asparagus genomes followed by bioinformatics analysis. We generated 17 Gb of sequence (12×coverage) and assembled them into 163,406 scaffolds with a total cumulated length of 400 Mbp, which represent about 30% of asparagus genome. Overall, TEs masked about 53% of the A. officinalis assembly. Majority of the identified TEs belonged to LTR retrotransposons, which constitute about 28% of genomic DNA, with Ty1/copia elements being more diverse and accumulated to higher copy numbers than Ty3/gypsy. Compared with LTR retrotransposons, non-LTR retrotransposons and DNA transposons were relatively rare. In addition, comparison of the abundance of the TE groups between male and female genomes showed that the overall TE composition was highly similar, with only slight differences in the abundance of several TE groups, which is consistent with the relatively recent origin of asparagus sex chromosomes. This study greatly improves our knowledge of the repetitive sequence construction of asparagus, which facilitates the identification of TEs responsible for the early evolution of plant sex chromosomes and is helpful for further studies on this dioecious plant. [ABSTRACT FROM AUTHOR]

Rationale: It is clear that lipid disorder and inflammation are associated with cardiovascular diseases and underlying atherosclerosis. Nur77 has been shown to be involved in inflammatory response and lipid metabolism. Objective: Here, we explored the role of Nur77 in atherosclerotic plaque progression in apoE−/− mice fed a high-fat/high cholesterol diet. Methods and Results: The Nur77 gene, a nuclear hormone receptor, was highly induced by treatment with Cytosporone B (Csn-B, specific Nur77 agonist), recombinant plasmid over-expressing Nur77 (pcDNA-Nur77), while inhibited by treatment with siRNAs against Nur77 (si-Nur77) in THP-1 macrophage-derived foam cells, HepG2 cells and Caco-2 cells, respectively. In addition, the expression of Nur77 was highly induced by Nur77 agonist Csn-B, lentivirus encoding Nur77 (LV-Nur77), while silenced by lentivirus encoding siRNA against Nur77 (si-Nur77) in apoE−/− mice fed a high-fat/high cholesterol diet, respectively. We found that increased expression of Nur77 reduced macrophage-derived foam cells formation and hepatic lipid deposition, downregulated gene levels of inflammatory molecules, adhesion molecules and intestinal lipid absorption, and decreases atherosclerotic plaque formation. Conclusion: These observations provide direct evidence that Nur77 is an important nuclear hormone receptor in regulation of atherosclerotic plaque formation and thus represents a promising target for the treatment of atherosclerosis. [ABSTRACT FROM AUTHOR]

Aims: Atherosclerosis is a chronic inflammatory disease and represents the major cause of cardiovascular morbidity and mortality. There is evidence that dihydrocapsaicin (DHC) can exert multiple pharmacological and physiological effects. Here, we explored the effect of DHC in atherosclerotic plaque progression in apoE−/− mice fed a high-fat/high-cholesterol diet. Methods and Results: apoE−/− mice were randomly divided into two groups and fed a high-fat/high-cholesterol diet with or without DHC for 12 weeks. We demonstrated that cellular cholesterol content was significantly decreased while apoA1-mediated cholesterol efflux was significantly increased following treatment with DHC in THP-1 macrophage-derived foam cells. We also observed that plasma levels of TG, LDL-C, VLDL-C, IL-1β, IL-6, TNF-α and CRP were markedly decreased while plasma levels of apoA1 and HDL-C were significantly increased, and consistent with this, atherosclerotic lesion development was significantly inhibited by DHC treatment of apoE−/− mice fed a high-fat/high-cholesterol diet. Moreover, treatment with both LXRα siRNA and PPARγ siRNA made the up-regulation of DHC on ABCA1, ABCG1, ABCG5, SR-B1, NPC1, CD36, LDLR, HMGCR, apoA1 and apoE expression notably abolished while made the down-regulation of DHC on SRA1 expression markedly compensated. And treatment with PPARγ siRNA made the DHC-induced up-regulation of LXRα expression notably abolished while treatment with LXRα siRNA had no effect on DHC-induced PPARγ expression. Conclusion: These observations provide direct evidence that DHC can significantly decrease atherosclerotic plaque formation involving in a PPARγ/LXRα pathway and thus DHC may represent a promising candidate for a therapeutic agent for the treatment or prevention of atherosclerosis. [ABSTRACT FROM AUTHOR]

Abstract: In order to identify amino acid residues crucial for the enzymatic activity of Δ8-sphingolipid desaturases, a sequence comparison was performed among Δ8-sphingolipid desaturases and Δ6-fatty acid desaturases from various plants. In addition to the known conserved cytb 5 (cytochrome b 5) HPGG motif and three conserved histidine boxes, they share additional 15 completely conserved residues. A series of site-directed mutants were generated using our previously isolated Δ8-sphingolipid desaturase gene from Brassica rapa to evaluate the importance of these residues to the enzyme function. The mutants were functionally characterized by heterologous expression in yeast, allowing the identification of the products of the enzymes. The results revealed that residues H63, N203, D208, D210, and G368 were obligatorily required for the enzymatic activity, and substitution of the residues F59, W190, W345, L369 and Q372 markedly decreased the enzyme activity. Among them, replacement of the residues W190, L369 and Q372 also has significant influence on the ratio of the two enzyme products. Information obtained in this work provides the molecular basis for the Δ8-sphingolipid desaturase activity and aids in our understanding of the structure–function relationships of the membrane-bound desaturases. [Copyright &y& Elsevier]

Abstract: The development of quantitative supercritical fluid extraction (SFE) methods for recovery of organochlorine pesticides from environmental samples requires three steps including analytes partition from the matrix into the bulk fluid, removal from the extraction cell and efficient collection. In early mass transfer studies, many empirical or theoretical models have been introduced to research the kinetic factors affecting extraction yields. In this study, the first time, the kinetic process of supercritical fluid extracting organochlorine pesticides (OCPs) from ginseng was simulated by Matlab/Simulink® interface based on the experimental data. The results showed that, within the permitted error range, the kinetic process simulation via Simulink® is another alternative approach, which is more convenient than conventional computer program. [Copyright &y& Elsevier]

The effect of nanometal powders (nano-grain-size aluminum powders and nanograin size nickel powders) on the ignition delay time of ammonium perchlorate composite propellants has been examined in detail within a carbon dioxide laser ignition system. A comparison of different experimental techniques for combustion-related properties evaluation, including burning rates, deflagration heat, and ignition temperatures of the ammonium perchlorate propellants containing nanometal powders is presented. A thermogravimetric analyzer is employed to investigate the thermal behavior of nano-grain-size and general-grain-size aluminum powders heated in air. The content of active aluminum in the combustion residue was measured by means of the titration. The results show that, with the cooperating effect of nanonickel powders, the addition of nanoaluminum powders in propellants can greatly increase the burning rate, shorten the ignition delay time, and improve the combustion efficiency of aluminum in the combustion of propellant. The individual application of nanometal powders (nanoaluminum or -nickel powders) displayed an intermediate effect, whereas the general-grain-size nickel powders had the least effect. The effect of nano-grain-size Al is determined to be on the solid-phase ignition of the propellant. The effect of nano-grain-size Ni is determined to be on the gas-phase ignition of propellant initially and the solid-phase ignition subsequently. [ABSTRACT FROM AUTHOR]

Transposable elements (TEs) and satellite DNAs, two major categories of repetitive sequences, are expected to accumulate in non-recombining genome regions, including sex-linked regions, and contribute to sex chromosome evolution. The dioecious plant, Humulus scandens , can be used for studying the evolution of the XX/XY 1 Y 2 sex chromosomes. In this study, we thoroughly examined the repetitive components of male and female H. scandens using next-generation sequencing data followed by bioinformatics analysis and florescence in situ hybridization (FISH). The H. scandens genome has a high overall repetitive sequence composition, 68.30% in the female and 66.78% in the male genome, with abundant long terminal repeat (LTR) retrotransposons (RTs), including more Ty3/ Gypsy than Ty1/ Copia elements, particularly two Ty3/ Gypsy lineages, Tekay and Retand. Most LTR-RT lineages were found dispersed across the chromosomes, though CRM and Athila elements were predominately found within the centromeres and the pericentromeric regions. The Athila elements also showed clearly higher FISH signal intensities in the Y 1 and Y 2 chromosomes than in the X or autosomes. Three novel satellite DNAs were specifically distributed in the centromeric and/or telomeric regions, with markedly different distributions on the X, Y 1 , and Y 2 chromosomes. Combined with FISH using satellite DNAs to stain chromosomes during meiotic diakinesis, we determined the synapsis pattern and distinguish pseudoautosomal regions (PARs). The results indicate that the XY 1 Y 2 sex chromosomes of H. scandens might have originated from a centric fission event. This study improves our understanding of the repetitive sequence organization of H. scandens genome and provides a basis for further analysis of their chromosome evolution process., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Zhang, Jia, Wang, Gao and Li.)

In recent years, fine particulate matter(PM 2.5 ) and ozone(O 3 ) have become the main air pollutants in cities in China. Volatile organic compounds(VOCs) are one of the important precursors of PM 2.5 , O 3 , and secondary organic aerosols. The establishment of VOCs emission inventory is therefore of great significance for controlling the amount of PM 2.5 and O 3 . To date, the coefficient method has been used, which has error transmission of activity level, parameter and model, leading to the uncertainty of emission inventory. Multivariate uncertainty quantitative analysis of VOCs emission inventory provides an accurate alternative which has not been reported in China. The bottom-up method is adopted to collect the activity level of each enterprise. The variables of pollution control measures are obtained from surveys conducted with enterprises. The VOCs emission inventory of Qingdao from industrial source is established using an optimized coefficient method. The uncertainty of the VOCs inventory on the impact of univariate and multivariate variables is simulated by combining the Monte Carlo method(MC) with Latin hypercube sampling method(LHS). The results show that the total VOCs emissions were 44700 tons from industrial sources in 2019(unoptimized coefficient method:31100 tons).The rubber and plastic industries, metal products, and oil/coal/other fuel processing contributed more VOCs, which accounted for 40.26% of the total emissions. The uncertainty of multivariate simulation is higher than that of single variable. The uncertainty from process(-9.72%-230.51%) and solvent using source(-14.14%-122.77%) is significantly higher than uncertainty from combustion source(-15.62%-36.41%). The main sectors affecting the uncertainty of the VOCs inventory include:the chemical, papermaking, and textile industries(emission factors); metal, automobile manufacturing, and chemical industries(removal rate, facility operating rate); industries of petroleum processing and ferrous metal smelting(too few samples). VOCs emissions are mainly distributed in the east of the West Coast New district, north of Dazhu Mountain, south of Jimo district, north of Chengyang district, northeast of Jiaozhou district, built-up area of Pingdu district, and southeast of Laixi district.

Adipocytes and immune cells are vital for the development of adipose tissue. Adipokines secreted by adipocytes regulate adipogenesis and body metabolism. Chemerin is one of the adipokines. However, the function and mechanism of chemerin in adipose tissue are not fully illuminated. Compared with wild type (WT) mice, Rarres2 -/- mice gained weight and significantly increased fat distribution in subcutaneous adipose tissue (SAT), rather than visceral adipose tissue (VAT) on high fat diet (HFD). PPARγ and C/EBPα, the master regulators of adipogenesis, were up-regulated in SAT and down-regulated in VAT in Rarres2 -/- mice comparing with WT mice. Inspite of chemerin deficiency or not, the ratio of adipocyte-progenitors to total cells and the differentiation capacity of adipocyte-progenitors were similar in SAT and VAT, but macrophage infiltration in VAT was more severe than in SAT in Rarres2 -/- mice. Furthermore, CD45 + immune cells supernatant from Rarres2 -/- SAT promoted the differentiation of adipocyte-progenitors and 3T3-L1 cells. Adipokine array assay of CD45 + immune cells supernatant revealed that metalloproteinase inhibitor 1 (TIMP1), an inhibitor of adipogenesis, was reduced in Rarres2 -/- SAT, but increased in Rarres2 -/- VAT. As we specifically knocked down chemerin in SAT, TIMP1 was down-regulated and adipogenesis was promoted with reducing infiltration of macrophages. The present study demonstrates that the effects of chemerin on adipose tissue is depot different, and specific knock down chemerin in SAT promote adipogenesis and improve glucose tolerance test (GTT) and insulin tolerance test (ITT). This suggests a potential therapeutic target for chemerin in the treatment of obesity related metabolic disorder., (© 2020 Chongqing Medical University. Production and hosting by Elsevier B.V.)

Abstract　　The promyelocytic leukemia (PML) gene encoded PML protein as a tumor suppressor protein, plays important roles in the occurrence and development of various cancers including acute promyelocytic leukemia. Recent studies have indicated that there are a variety of post-translational modifications of the PML protein, such as SUMOylation, ubiquitination, phosphorylation, and acetylation in cells. These modifications of the PML protein can directly affect the formation of PML nuclear bodies (PML-NBs), repair DNA damage, and modulate cell apoptosis. Furthermore, the abnormal modifications of PML not only result in the occurrence of hematopoietic tumors, but also are closely related to the drug-resistance of cancer. Therefore, investigating the post-translational modifications of PML is significant to uncover the mechanism of formation and functions of PML-NBs, thus contributing to the prevention and treatment of related hematopoietic tumors. In this review, the characteristics of the post-translational modifications of PML protein and the relationship between these modifications and functions of PML-NBs are summarized so as to provide the potential targets for the treatment of related cancers.

Classical forward genetic analysis relies on construction of complicated progeny populations and development of many molecular markers for linkage analysis in genetic mapping, which is both time- and cost-consuming. The recently developed MutMap is a new forward genetic approach based on high-throughput next-generation sequencing technologies. It is more efficient and affordable than traditional methods. Moreover, new extended methods based on MutMap have been developed: MutMap+, which is based on self-crossing; MutMap-Gap, which is used to recognize the causative variations occurring in genome gap regions; QTL-seq, a method similar to MutMap for mapping quantitative trait loci. These methods are free from constructing complicated mapping population, genetic hybridization and linkage information. They have greatly accelerated the identification of genetic elements associated with interested phenotypic variation. Here, we review the basic principles of MutMap, and discuss their future applications in next generation sequencing-based forward genetic mapping and crop improvement.

Chuangxinmycin (CM) from Actinoplanes tsinanensis was an antibiotic discovered by Chinese scientists about 40 years ago. It contains a new heterocyclic system of indole fused with dihydrothiopyran, whose biosynthetic mechanism remains unclear. CM is used as an oral medicine in the treatment of bacterial infections in China. The simple structure makes CM as an attractive candidate of structure modification for improvement of antibacterial activity. Recently, we analyzed the secondary metabolites of Actinoplanes tsinanensis CPCC 200056, a CM producing strain, as a natural CM analogue. We discovered the first natural CM analogue 3-demethylchuangxinmycin (DCM) as a new natural product. Compared to CM, DCM exhibited a much weaker activity in the inhibition of the bacterial strains tested. The finding provides valuable information for the structure-activity relationship in the biosynthesis of CM.

Adenosine triphosphate-binding cassette transporter A1 (ABCA1) is a crucial cholesterol transporter and plays a central role in the high density lipoproteins (HDL) cholesterol metabolism and lipid clearance from the foam cell. Lipoxin A4 (LXA4) is an endogenous lipid mediator that requires cell-cell interaction or cell-platelet interaction for its synthesis. The roles of LXA4 on inflammatory responses are well described, while its effects on mediating ABCA1 and underlying mechanisms remain unclear. In this study, we showed that LXA4 significantly increases expression of ABCA1 and LXRα in a dose-dependent manner in THP-1 macrophage-derived foam cells. Cellular cholesterol content was decreased while cholesterol efflux was increased by LXA4 treatment. However, after short interfering RNA of LXRα, the effects of LXA4 on ABCA1 expression and cholesterol metabolism were significantly abolished. These results provide evidence that LXA4 increases ABCA1 expression and promotes cholesterol efflux through LXRα pathway in THP-1 macrophage-derived foam cells.

Background: Population aging and the incremental use of high-tech instruments increase the demand for radiological examinations and treatments in medical services. The exposure of radiologists and other medical workers to medical treatment radiation may thus be increased., Objectives: The aim of the study was to explore the average number of cancer hospitalizations and use of hospitalization as cancer treatment for radiologists compared with that for family medicine physicians, as well as the trends in the annual average number of cancer hospitalizations among radiologists., Methods: Research data were obtained from the 2000-2010 Taiwan National Health Insurance Research Database. These samples collected for this study were unbalanced panel data., Results: The average number of cancer hospitalizations for radiologists from 2000 to 2010 ranged between 3.67 and 28.26‰. After controlling the effects of gender, age, hospital accreditation level and year using generalized estimating equations with a binomial distribution and logit link function, our study found that radiologists had non significant higher risk of cancer hospitalizations compared with family medicine physicians. However, the average number of cancer hospitalizations for radiologists showed an annual decline from 2000 to 2010., Conclusions: Compared with family medicine physicians, radiologists had non significant higher risk of cancer hospitalizations. The data period examined in this study was only 11 years. Considering the numerous new radiological procedures currently in use in modern medical treatments, the health status of medical radiation workers should be continuously monitored in the future.

The XY sex-determination system is crucial for plant reproduction. However, little is known about the mechanism of the origin and evolution of the XY sex chromosomes. It has been believed that a pair of autosomes is evolved to produce young sex chromosomes (neo-X chromosome and neo-Y chromosome) by loss of function or gain of function mutation, which influences the development of pistil or stamen. With the aggravation of the recombination suppression between neo-X and neo-Y and consequent expanding of the non-recombination region, the proto-sex chromosomes were finally developed to heteromorphic sex chromosomes. Accumulation of repetitive sequences and DNA methylation were probably involved in this process. Transposons, as the most abundant repetitive sequences in the genome, might be the initial motivation factors for the evolution of sex chromosome. Moreover, transposons may also increase heterochromatin expansion and recombination suppression of sex chromosome by local epigenetics modification. In this review, we summarize the function of transposon accumulation and the relationship between transposon and heterochromatization in the evolution of plant sex chromosome.

In 3T3-L1 preadipocyte differentiation, the CCAAT/enhancer-binding protein-β (C/EBPβ) is an important early transcription factor that activates cell cycle genes during mitotic clonal expansion (MCE), sequentially activating peroxisome proliferator-activated receptor-γ (PPARγ) and C/EBPα during terminal differentiation. Although C/EBPβ acquires its DNA binding activity via dual phosphorylation at about 12-16 h postinduction, the expression of PPARγ and C/EBPα is not induced until 36-72 h. The delayed expression of PPARγ and C/EBPα ensures the progression of MCE, but the mechanism responsible for the delay remains elusive. We provide evidence that G9a, a major euchromatic methyltransferase, is transactivated by C/EBPβ and represses PPARγ and C/EBPα through H3K9 dimethylation of their promoters during MCE. Inhibitor- or siRNA-mediated G9a downregulation modestly enhances PPARγ and C/EBPα expression and adipogenesis in 3T3-L1 preadipocytes. Conversely, forced expression of G9a impairs the accumulation of triglycerides. Thus, this study elucidates an epigenetic mechanism for the delayed expression of PPARγ and C/EBPα.

Objective: To establish an effective separation system of 2-DE for the proteome of caudal gland, and provide foundation for revealing the mechanisms of histological development and pharmacological activities., Method: The total proteins of caudal gland were extracted by TCA/acetone precipitation, phenol extraction/methanol-ammonium acetate precipitation and trizol-base method respectively and separated by immobilized pH gradient (IPG) strips prior to SDS-PAGE. Loading protein sample size and isoelectric focusing conditions were optimized. The gels were stained with Coomassie brilliant blue, scanned and then analyzed using PDQuest 8.0 analysis software., Result: The total proteins of caudal gland extracted by trizol-base method were the highest quality and could meet the needs of 2-DE. With 300 microg of proteins loaded on 7 cm pH 3-10 IPG strip followed by isoelectric focusing program II ,a satisfying 2-DE profiles were obtained. The total number of disticted protein spots was 209 with the optimized system., Conclusion: A well-resolved 2-DE patterns of caudal gland were obtained by this optimized system. This method could be applied to prepare other similar tissue sample and 2-DE studies.

Objective: The aim of this study was to access the relationship of osteolytic bone metabolic markers such as serum type I collagen carboxy-terminal telopeptide (sICTP), N-terminal cross-linked telopeptides of type I collagen (uNTx), urinary pyridinoline (uPyd) with the therapeutic effect in breast cancer patients with bone metastases., Methods: 120 patients with breast cancer were included in this study. The levels of sICTP, uNTx and uPYD were measured by ELISA assay. The differences were compared between patients with and without bone metastasis. The patients with bone metastasis were treated and followed up as clinically indicated., Results: The levels of all above mentioned biomarkers in patients with bone metastasis were significantly higher than that in patients without bone metastasis (P < 0.01). A significant correlation was found between each two markers (r > 0.5, P < 0.01). The biomarkers were examined again in 45 patients with bone metastasis after treatment to evaluate the treatment response. The median follow-up was 10 months. Based on clinical evaluation criteria, 25 patients were responders and 20 were non-responders. For responders, after 3 months treatment, the levels of the three bone markers were significantly reduced (P = 0.025, P < 0.001, P < 0.001). But for non-responders, with progression of bone lesions, the levels of the three markers were significantly raised (P = 0.011, P = 0.002, P = 0.002). By means of multiple logistic regression with stepwise selection, the uPyd and uNTx activities were closely correlated with treatment response (OR = 17.0, P = 0.019; OR = 16.7, P = 0.015), however, the sICTP did not show any correlation with treatment response P = 0.841)., Conclusion: The levels of sICTP, uNTx and uPyd may be used as indicators in assessment of the effect of antiresorptive treatment and evaluation of prognosis in breast cancer patient with bone metastases.

Effects of fullerene soot (FS) on the thermal decomposition and Fourier transform infrared spectrum (FTIR) of polyethylene glycol (PEG, molecular weight= 20,000) were investigated by thermal analysis (TG-DTG) and in-situ FTIR experiments. The results of thermal analytical experiments showed that the addition of FS postponed not only the initial decomposition temperatures but also the temperatures at maximum decomposition rate of PEG. The maximum decomposition peak temperatures increased and the maximum decomposition rates were lowered even with the addition of 0.1%FS. The in-situ FTIR experiments proved that there was no difference between the IR spectra of PEG and PEG with 10%FS. There wasn't any new chemical band formed but Vander waals force between FS and PEG. Although the addition of FS didn't influence the constitution of decomposition products of PEG, it obviously increased the decomposition temperature and the decomposition rate of PEG. Through the researches on condensed phase and gaseous phase FTIR spectrum of PEG and PEG with 10%FS, one could see that the effect of FS on the condensed phase FTIR spectrum of PEG was not obvious, but the addition of FS markedly enhanced the occurrence temperatures of most gaseous decomposition products of PEG. These results showed that the effect of FS on thermal decomposition of PEG was through the absorbance and desorption of gaseous phase decomposition products. With the temperature elevated, the gaseous products were gradually desorbed from the activity centers and the decomposition of PEG continued. The thermal decomposition peak of PEG was moved toward hi gher temperature with the addition of FS than that without FS.

Objective: To evaluate the efficacy and safety of docetaxel and capecitabine combination chemotherapy (DC regimen) for patients with anthracycline-resistant metastatic breast cancer., Methods: Thirty-two patients with anthracycline-resistant metastatic breast cancer were treated with a docetaxel and capecitabine combination regimen. All patients received oral administration of capecitabine at a dose of 1250 mg/m(2) twice daily, within 30 min after meal on D1 to D14, and intravenous infusion of docetaxel at a dose of 75 mg/m(2) on D1. The regimen was repeated every 3 weeks., Results: A total of 126 cycles of DC regimen were administered in the 32 cases, with a median of 4 cycles. The overall response rate was 46.9%. Among the 32 patients, there were complete response in 1, partial response in 14, stable disease in 11 and progressive disease in 6 cases. The median time to progression (TTP) was 5.6 months. The one-year survival rate was 56.3%. The effective cases in different metastatic organs were: 8 cases in the lung, 6 cases in the liver, 3 cases in the soft tissue and 3 cases in the lymph nodes. The common adverse reactions were myelosuppression, hand-foot syndrome, nausea and vomiting. Neutropenia was observed in 84.4% of the patients. Two patients developed degree IV myelosuppression., Conclusion: The combination chemotherapy regimen of docetaxel plus capecitabine is well-tolerated and effective for anthracycline-resistant metastatic breast cancer.

The mechanisms for AP of the main compositions of composite propellants with additives such as ammonium oxalate (AO), strontium carbonate (SC) and AO/SC were studied by FTIR and DSC. The analysis of FTIR shows that AO leads to a delay in the temperature for the disappearance of absorption peaks of AP. SC reacts with HClO4 from AP decomposition and produces more stabilized Sr(ClO4)2 in the condensed phase. FTIR proves the production of Sr(ClO4)2. The analysis of DSC shows that the temperature for high decomposition exothermic peak of AP with AO is increased, but there is no effect on the temperature for low decomposition exothermic peak of AP. Both the temperature for the low and high decomposition exothermic peaks of AP are increased by the addition of SC. Although the temperature for decomposition exothermic peak of AP is increased with the addition of AO/SC, the experimental result shows that SC and AO didn't produce synergetic effects for the high temperature decomposition of AP at low pressure. Based on the above experimental results, the mechanisms of inhibiting the decomposition of AP for AO and SC are discussed.

The thermal decomposition processes of 2-H-heptafluoropropane were investigated during a 30 second reaction time and at temperatures of 400, 500, 600, 700 and 800 degrees C using fast pyrolysis method and Fourier transform infrared spectra (FTIR) and gas chromatography/mass spectrometry (GC/MS) analytical techniques. The results indicate that the reaction temperatures have the obvious effects on the thermal decomposition of 2-H-heptafluoropropane. The 2-H-heptafluoropropane is steady at first three temperatures, whereas starts to obviously decompose at 700 degrees C and undergoes intense decomposition at 800 degrees C. At the same time, coke formation was observed on the surface of the reactor at 800 degrees C. Moreover, three cyclocompounds, 1,2-bis(trifluoromethyl) perfluoroindane, perfluoro(1-ethylideneindane) and octafluoronaphthalene, were for the first time discovered in the products of thermal decomposition at 800 degrees C. This demonstrates that 2-H-heptafluoropropane experiences not only simple decomposition, but also cyclization and the polymerization reactions under high temperature thermal decomposition conditions.

Objective: The liposomes containing extracts of Tripterygium wilfordii were prepared and the possibility of entrapment of complex chemicals by liposomes were studied., Method: The liposomes containing extracts of T. wilfordii were prepared by thin-film dispersion method, the effect of process parameters and composition of materials on the entrapment efficiency of the main components were studied. The stability of the liposomes dispersion was also evaluated., Result: The liposomes made by thin-film dispersion method were mostly small unilamellar vesicles and their particle size was 30 nm to approximately 50 nm. The optimum entrapment efficiency of tripterine and the total alkaloids were respectively 98.10% and 88.63% but the liposomes dispersion was unstable when kept at 4 degrees C., Conclusion: The complex chemicals can be entrapped by the liposomes, but its stability need to be improved furtherly.

Objective: To study the method of extraction of sex hormone from antler velvet with supercritical CO2., Method: Supercritical fluid extraction (SFE) was used to extract sex hormone from antler velvet and radioimmunoassay (RIA) was used to analyze the extracts. The chemical compositions in extracts were identified by GC-MS, TLC and HPLC, respectively., Result: The experimental results indicated that the extraction yield was 1.56% when 85% ethanol was used as co-solvent at temperature of 65 degrees C and extraction pressure of 30 MPa. Estradiol and progesterone in the extracts were 3.07, 776.18 ng x g(-1) respectively., Conclusion: It is feasible to extract hormone from antler velvet with supercritical CO2.

Objective: To establish the chromatographic fingerprint of supercritical carbon dioxide extract of Tripterygium wilfordii., Method: HPLC method was applied for quality assessment of T. Wilfordii, HPLC analysis was performed on Kromasil C18 (4. 6 mm x 250 mm, 5 microm) with the mixture of acetonitrile-1% per thousand H3PO4, as mobile phase in gradient mode. The samples were detected at UV of 267 nm with column temperature of 35 degrees C, analytic time was 80 min; Flow-rate was 1.0 mL x min(-1). The chromatographic fingerprint of ten batches of samples was determined, for establishing the chromatographic fingerprint of T. Wilfordii., Result: Indicating 27 peaks in common, identified 21 peaks with chemical reference and HPLC-MS, and the HPLC fingerprint was established., Conclusion: The method is steady and accurate with a good repeatability and can be used as a quality control method for T. Wilfordii.

The thermal decomposition of GAP and GAP/B in air and nitrogen were studied by FTIR and TG-DTG. The analysis by FTIR and TG-DTG shows that the azide group elimination reactions of GAP begin at about 170 degrees C and finish around 250 degrees C, and the depolymerization of GAP delays by 40 degrees C; Boron changes the mechanism of thermal decomposition process of GAP, and the results show that GAP/B starts losing mass between 55 and 70 degrees C, which is much earlier than GAP itself does. Furthermore, the depolymerization of GAP almost takes place at the same temperature with the azide group elimination. Some kinetics parameters of the reactions were calculated based on Kissinger's processing methods. The results show that the activation energies of the thermal decomposition of GAP and GAP/B are lower and the reactions are easier to occur under air. The possible reason is that the oxygen containing thermal decomposition of GAP has happened.

The thermal behavior of polyester-polyurethane and polyether-polyurethane in air atmosphere was investigated by using FTIR analysis in the temperature range from 20 to 400 degrees C. The thermal degradation behaviors of polyester-polyurethane and polyether-polyurethane in different atmospheres were investigated by using thermogravimetry analysis (TG) in the temperature range from 20 to 700 degrees C. The FTIR results together with the TG investigations showed that polyester-polyurethane has two degradation steps in air, but polyether-polyurethane has only one degradation step. The thermal analysis results also showed that the onset degradation temperature of polyether-polyurethane is lower than that of polyester-polyurethane, suggesting that the thermal stability of polyester-polyurethane is higher than polyether-polyurethane, and the onset degradation temperature of polyurethane in air is lower than that in nitrogen, suggesting that the presence of oxygen affects significantly the break of the polymeric chains.

Objective: To study the evidence of severe acute respiratory syndrome (SARS) infection among close contacts to SARS patients and the level of sera IgG antibody in SARS cases., Methods: Specific IgG antibody against SARS-CoV in serum samples from contacts to patients, five months before an SARS outbreak in Beijing. Neutralized test, ELISA and immunity adherence test were studied. Samples were collected after clinical onset of patients or close contacts to patients, for 22 - 24 weeks. 19 close contacts and 13 cases were included in the study., Results: In close contacts, all tests were negative on three methods. All SARS cases were positive except one by immunity adherence test. The neutralized antibody levels were from 1:16 to 1:203, with medium level of 1:43., Conclusion: According to our survey, there was no latent infection among close contacts. IgG antibody in sera continued to be at higher levels among SARS cases 22 - 24 weeks after onset.

Background & Objective: Oxaliplatin is effective for the advanced colorectal cancer (CRC) as a second-line drug; however, the efficiency and adverse reaction of oxaliplatin made in China are not yet clear. The aim of this project was to evaluate the efficacy and the toxicities of oxaliplatin made in China in the treatment of the patients with advanced CRC who were resistant to 5-fluorouracil (5-Fu)., Methods: The previously 5-FU-resistant patients with CRC were treated with single agent of oxaliplatin 130 mg/m(2), i.v., d1, repeated every 3 weeks., Results: A total of 31 cases with advanced CRC resistant to 5-Fu were enrolled, and 28 cases were valuable for efficacy assessment. One patient reached complete response (CR), 3 reached partial response (PR), and the overall response rate was 14.29% (with ITT equal to 12.9%). The major adverse effects were mild neuro-sensory toxicity, mild myelosuppression,and nausea/vomiting., Conclusion: The oxaliplatin made in China is effective in the treatment of advanced CRC resistant to 5-Fu, and the adverse effects are mild.