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Catalytic elimination of formaldehyde (HCHO) was investigated over Cu-Al2O3 catalyst at room temperature. The results indicated that no oxidation of HCHO into CO2 occurs at room temperature, but the adsorption of HCHO occurs on the catalyst surface. With the increase of gas hourly space velocity (GHSV) and inlet HCHO concentration, the time to reach saturation was shortened proportionally. The results of the in situ DRIFTS, Density functional theory calculations and temperature programmed desorption(TPD) showed that HCHO was completely oxidized into HCOOH over Cu-Al2O3 at room temperature. With increasing the temperature in a flow of helium, HCOOH was completely decomposed into CO2 over the catalyst surface, and the deactivated Cu-Al2O3 is regenerated at the same time. In addition, although Cu had no obvious influence on the adsorption of HCHO on Al2O3, Cu dramatically lowered the decomposition temperature of HCOOH into CO2. It was shown that Cu-Al2O3 catalyst had a good ability for the removal of HCHO, and appeared to be promising for its application in destroying HCHO at room temperature.

To label mouse ES cells,a cell line derived from the inner cell mass of 3.5-day blastocysts,with enhanced green fluorescent protein (EGFP), the vector of pRex-1-EGFP was transferred into mouse ES cells by electroporation. The expressions of Rex-1 in undifferentiated and differentiated ES cells were detected by the microscopic observation of EGFP and by RT-PCR. The results showed that the EGFP gene was transferred into the mouse ES cell line, and the transfected cells in undifferentiated state showed high levels of EGFP expression. When the cells began to differentiate, the EGFP expressions were gradually reduced. A mouse ES cell line expressing EGFP under the control of Rex-1 gene promoter was generated. The cell line provides a powerful approach for the research of the process of mammalian development and for the screening of small molecules that can regulate this process.

Obesity is a clinical syndrome caused by genetic and environmental factors and has a relatively high heretability. Seven genes, of whose mutations each can independently result in severe human obesity, have been cloned. Six of them are involved in the appetite controlling by the central nervous system, and one is related to the regulation of adipocyte differentiation. Investigations into the genetic basis of human obesity are important for understanding the mechanism of obesity formation and for design and screening of anti-obesity drugs.

A cell model is desired for adipocyte differentiation investigation and for high-throughput screening of anti-obesity and anti-diabetes molecules from chemical resources due to the world wide epidemic of obesity and diabetes. In order to establish such a cell model, a plasmid of pPPARgamma2-promoter-EGFP was constructed by inserting a 660bp sequence of mouse PPARgamma2 promoter into the Ase I and Kpn I sites of pEGFP-N3 and transferred into 3T3-L1 preadipocyte cells. The cells were induced to differentiate and the expression of PPARgamma2 was detected by the microscopic observation of EGFP and by RT-PCR assays. The results showed that the EGFP gene expression patterns were similar to that of pPPARgamma2's, which indicated that the EGFP gene was transferred into the mouse 3T3-L1 preadipocyte cells, and its expression was under the control of pPPARgamma2 promoter. RT-PCR assays showed that the EGFP expression authentically represented the stable expression of PPARgamma2. In conclusion, a preadipocyte cell line expressing EGFP under the control of the promoter of adipocyte-specific expression gene PPARgamma2 was generated. The cell line provides a powerful approach for the research of adipocyte differentiation and for the high-throughput screening of anti-obesity and anti-diabetes chemicals.

Fat tissue and adipocytes have been exclusively investigated in the past two decades, especially in the last ten years, due to the following two reasons. Firstly, more and more studies showed that fat tissue is not only an organ for energy storage, but also an endocrine one that can secret many kinds of hormones or hormone-like peptides. Secondly, the established preadipocyte cell lines have been providing powerful tools for the in vitro research of adipocyte differentiation, because these immortal cell lines authentically represent, to a great extend, the in vivo situations of these cells and can be induced to differentiate into mature adipose cells with proper hormones. It has been demonstrated that there exists close relations between adipocyte differentiation and many physiological or pathological processes including saccharide and fat metabolism, energy balance, obesity, diabetes, hyperlipidemia and breast cancer. It is very important to make known the differentiation mechanisms of preadipocyte into adipocyte for understanding the above mentioned diseases and for screening anti-obesity and anti-diabetes drugs.

The preparation of ethanol-diesel fuel blends and their emission characteristics were investigated. Results showed the absolute ethanol can dissolve in diesel fuel at an arbitrary ratio and a small quantity of water(0.2%) addition can lead to the phase separation of blends. An organic additive was synthesized and it can develop the ability of resistance to water and maintain the stability of ethanol-diesel-trace amounts of water system. The emission characteristics of 10%, 20%, and 30% ethanol-diesel fuel blends, with or without additives, were compared with those of diesel fuel in a direct injection (DI) diesel engine. The experimental results indicated that the blend of ethanol with diesel fuel significantly reduced the concentrations of smoke, hydrocarbon (HC), and carbon monoxide (CO) in exhaust gas. Using 20% ethanol-diesel fuel blend with the additive of 2% of the total volume, the optimum mixing ratio was achieved, at which the bench diesel engine testing showed a significant decrease in exhaust gas. Bosch smoke number was reduced by 55%, HC emission by 70%, and CO emission by 45%, at 13 kW/1540 r/min. However, ethanol-diesel fuel blends produced a few ppm acetaldehydes and more ethanol in exhaust gas.

The uracil in DNA comes from either the misincorporation of dUTP in place of dTTP or deamination of cytosine. In the latter case, it can result in a GC to AT transition mutation if the uracil is not removed before DNA replication. Base excision repair (BER) is a major pathway for removing DNA lesions arising from endogenous processes as well as those induced by exposure to exogenous chemicals or irradiation. BER is initiated by DNA glycosylases that excise aberrant bases from DNA by cleavage of the N-glycosidic bond linking to the base of its deoxyribose sugar. Uracil N-glycosylase (UNG) is the enzyme responsible for the first step in the BER pathway that specifically removes uracil from DNA. The UNG gene undergoes both temporal and spatial regulation mainly at the level of transcription. Normally cancer cells undergo over-proliferation and up-regulate their UNG during tumorigenesis. In this study we examine the correlation between UNG level and carcinogenesis, and explore the possibility of using UNG as a marker for cancer diagnosis. Human UNG gene was amplified from the total RNA of the human choriocarcinoma cell line, JEG-3, by RT-PCR. After purification, the 942bp full-length UNG cDNA coding sequence was digested with EcoR I and Sal I, and cloned into the digested pET-21 to construct a recombinant vector, pUNG. The UNG protein was expressed under the control of T7 promoter in E. coli BL21 (DE3) cells induced with IPTG. After ultrasonic treatment, the cell lysate and precipitate were analyzed by SDS-PAGE and a 39kD band was detected. The plasmid was serially diluted at appropriate concentrations and employed as standards in the subsequent quantification. Total RNAs were extracted from 18 pairs of clinical samples, each pair contains a sample of esophageal squamous cell carcinoma (ESCC) tissue and its surrounding normal esophageal epithelia. The copy numbers of UNG mRNA in these RNA samples were determined by real-time quantitative RT-PCR using a Lightcycler (Roche). UNG was present in 13 cases of ESCC (13/18, n = 18) but absent in all of the normal tissues. The results indicated that there was a correlation between high level of UNG expression and the carcinogenesis of ESCC.

Sigma and pi polarized absorption spectra of Tm:YVO4 crystal have been measured at room temperature. Considering the difference of the sigma and pi polarized absorption spectra and the changing of the refractive index with different wavelengths, we calculate the intensity parameters of Tm3+ in crystal YVO4 which are omega 2 = 1.9416 x 10(-20) (cm2), omega 4 = 0.1568 x 10(-20) (cm2), omega 6 = 0.3963 x 10(-20) (cm2) by Judd-Ofelt theory. The spectra characteristic parameters, such as radiative transition rates, luminescence branching ratio, total radiative lifetime and integral cross-section are also calculated. The results show that the spontaneous rate of the transition 1D2-->3F4 is much higher than that of the transition 1D2 to other levels.

In order to get CgA gene antisense DNA transgenic mouse, we constructed the CgA gene antisense DNA plasmid pCAS2C and microinjected it into the female pronucleus of fertilized mouse eggs, and transplanted them into oviduct of the foster. Every offspring of the fosters was determined by the PCR method. The positive mice had a 300 bp DNA electrophoresis band. We selected two male positive mice from 50 offspring survived of the pseudomother. Then, two positive mice crossed with normal mice respectively to reproduce offspring of F1. All offspring of F1 were determined by PCR to select positive offspring. Positive offspring of F1 carried only one allele of pCAS2C (heterozygous pCAS2C/-). Positive F1 offspring were selfcrossed, 1/4 offspring of F2 carrying two unites of one allele pCAS2C (pCAS2C/pCAS2C) are homozygous. Then, all offspring of homozygous F2 crossed with normal mice, could produce 300 bp DNA electrophoresis band by PCR. Total RNA of brain tissue of transgenic mouse was used to RT-PCR method, the 300 bp DNA product was obtained. The result indicates that the reading frame of CgA antisense DNA of pCAS2C has expressed in the transgenic mice.

Of the three lambda chain subtypes made by inbred mice, chains of the lambda 1 subtype are much more frequent than those of the other subtypes (lambda 2,lambda 3) in antibodies (Ab) to those few antigenic structures that are known to elicit responses, in which lambda chains are the predominant type of light chain [(4-hydroxy-3-nitrophenyl)acetyl (NP) and dextran]. The reason for the frequency differences are not understood, and the large difference between the lambda 1 and lambda 3 frequencies is particularly puzzling, because in nearly all (about 95%) chains of these subtypes the N-terminal 97 or 98 amino acids are endoded by the same V lambda-gene segment. In an effort to identify an Ab response that has different lambda subtype frequencies, we analyzed the light chains of the Ab made by BALB/c and B6 mice in response to 2,4-dinitrophenylated chicken gamma globulin (DNP-CGG). We found that approximately 40% of the elicited anti-DNP molecules had lambda chains and of these approximately 40% were of the lambda 2 or lambda 3 subtype. Polyacrylamide gel electrophoresis indicated that the lambda 2 and lambda 3 chains were about equally abundant. Similar lambda subtype frequencies were found in the anti-DNP Ab produced by the hybridoma made with spleen cells from the same immunized mice. In the anti-DNP Ab elicited by DNP-CGG and in the anti-NP Ab elicited by NP-CGG the different lambda subtype frequencies (lambda 1/lambda 2 + lambda 3 = ca. 1.0-1.5 in anti-DNP and ca. 30 in anti-NP) were unaffected by immunizing mice with each of these antigens alone or with a mixture of the two. This finding, though preliminary, suggests that isotype-specific regulatory T cells are not responsible for the markedly different lambda subtype frequencies in anti-DNP and anti-NP Ab.

The relationship between "Spleen" and muscles was explored by determining the amount of muscular glycogen to indicate the stored energy in muscles. The amount of muscular glycogen in normal rats was 6.34 +/- 0.20 mg/g muscles, it was much more than that in Spleen deficiency rats caused by rhubarb (4.27 +/- 0.40 mg/g muscles). In order to observe the effects of Jian Pi Yi Qi decoction on Spleen deficiency, the Spleen deficiency rats were divided into two groups, one of which was treated with Jian Pi Yi Qi decoction as experimental group, the other with distilled water as control. After one week, the amount of muscular glycogen in experimental group was 5.35 +/- 0.16 mg/g muscles and in control 4.63 +/- 0.15 mg/g muscles. It showed that the rising of the amount of muscular glycogen in experimental group was more than that in control with statistic significance but it was still lower than that in normal rats.