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Tourmaline is a class of boron-bearing aluminosilicate minerals. It has a complex chemical component and stable chemical property, and is difficult to decompose by wet methods. The high content of B2O3 makes it difficult to simultaneously determine major and minor elements in tourmaline. X-ray Fluorescence Spectrometry (XRF) was applied to determine Na2O, MgO, Al2O3, SiO2, P2O5, K2O, CaO, TiO2, V2O5, Cr2O, MnO, TFe2O3 in tourmaline samples with fusion sample preparation in this study. The dilution ratio of 1:10 was set for the sample to flux lithium tetraborate-lithium metaborate-lithium fluoride (quality ratio of 4.5:1:0.4) in order to eliminate the particle size effect and mineral effect. When the tourmaline reference materials were unavailable, soil, stream sediment and different types of rock reference materials were used to establish calibration curves. The accuracy of the method was verified using reference materials that have chemical compositions similar to tourmaline. The relative standard deviation (RSD, n=11) was less than 4.2%. The proposed method was used to determine four different tourmaline samples, the results were in good agreement with the values obtained by wet chemical methods. This method solved the problem that tourmaline is difficult to decompose and eliminated the interference effect of boron. The analytical results are accurate and reliable. Compared with other methods, this method is easy to operate and has a short analytical time.

Objective: To study the mechanism underlying the inhibitory effects of peroxisome proliferator-activated receptor γ (PPARγ) agonists on transforming growth factor β1 (TGF-β(1))-induced scarring of skin., Methods: Fibroblasts isolated from healthy adult skin were cultured in vitro and divided into blank control group (serum-free DMEM culture), TGF-β(1) group (with stimulation of 10 ng/mL TGF-β(1) for 48 hours), troglitazone group (with the same treatment as in TGF-β(1) group after stimulation of 10 µmol/L troglitazone for 2 hours), and 15-dioxygen prostaglandin J2 (15d-PGJ2) group (with the same treatment as in TGF-β(1) group after stimulation of 10 µmol/L 15d-PGJ2 for 2 hours) according to the stimulation added into DMEM. The expression of connective tissue growth factor (CTGF) was determined with Western blot. The mRNA levels of CTGF, matrix metalloproteinase-1 (MMP-1) and platelet-derived growth factor (PDGF) were determined with real-time fluorescence RT-PCR. Data were processed with one-way analysis of variance., Results: The expression of CTGF at mRNA and protein levels in skin fibroblasts were significantly increased in TGF-β(1) group as compared with control group; while expression of CTGF at mRNA and protein levels in 15d-PGJ2 and troglitazone groups were significantly decreased as compared with that in TGF-β(1) group. The mRNA level of MMP-1 in TGF-β(1) group (0.193 ± 0.051) was obviously lower than that in blank control group (1.281 ± 0.195, F = 12.811, P < 0.01), while the mRNA levels of MMP-1 in troglitazone group (0.417 ± 0.043) and 15d-PGJ2 group (0.485 ± 0.027) were significantly increased as compared with that in TGF-β(1) group (F = 12.811, P values all below 0.01). The mRNA level of PDGF in TGF-β(1) group (1.044 ± 0.237) was obviously higher than that in control group (0.349 ± 0.057, F = 16.848, P < 0.01), while the levels in troglitazone group (0.677 ± 0.055) and 15d-PGJ2 group (0.511 ± 0.017) were significantly decreased as compared with that in TGF-β(1) group (F = 16.848, P values all below 0.01)., Conclusions: The inhibitory effect of activated PPARγ on the expression of CTGF induced by TGF-β(1) may be the main mechanism of its inhibitory effect on TGF-β(1)-induced scarring on skin, and its influence on MMP-1 and PDGF may also be one of the underlying mechanisms.

3T3-L1-adipocytes produce the adipocyte complement related protein of 30 kD (ACRP30), which is exclusively expressed in differentiated adipocytes. Decreased expression of ACRP30 correlates with insulin resistance in mouse models of altered insulin sensitivity. Adiponectin, the human homologue of ACRP30, circulates in human plasma at high levels. Plasma adiponectin levels have been reported to be decreased in some insulin-resistant states, such as obesity and type II diabetes mellitus. Here, full-length adiponectin and its C-terminal globular head domain (gAdiponectin) were expressed in Escherichia coli and gAdiponectin was used to immunize a rabbit to obtain polyclonal antiserum with titer of 10,000. Adiponectin was detected in human plasma with the use of gAdiponectin anti-serum by Western blot analysis, which was also detected by gACRP30 anti-serum. Injection in alloxan-treated rats with purified recombinant fusion adiponectin or gAdiponectin transiently abolished hyperglycemia. So adiponectin and gAdiponectin might have activity as a glucose lowering agent and potentially as a therapeutic for metabolic disease. All these results suggested that the recombinant protein had biological activity, and provided a useful tool in further studies.

The gene C17orf25 was isolated from the liver by RACE PCR. nudt9 gene was screened by yeast two-hybrid method in MatchMaker human HeLa cDNA library. NUDT9 is an enzyme that has pyrophosphatase activity with ADP-ribose as its substrate. Fusion expression of C17orf25 and GFP and computer analysis showed that C17orf25 was probably located in mitochondria. Furthermore, C17orf25 may suppress the cell growth by interaction with NUDT9.

An expression release system for heterogeneous proteins in Escherichia coli mediated by the colicin release gene(kil gene) was constructed. The system is based on the ability of the Kil protein to release periplasmic proteins into the growth medium. beta-lactamase, an E.coli periplasmic protein, and prolyl endopeptidase (PEP), a periplasmic protein of Aeromonas punctata subsp. punctata were used as report proteins. Commonly, these two proteins are seldom released into the growth medium. The results indicated that the released amounts of the beta-lactamase and of the prolyl endopeptidase were nearly 5 fold and 4 fold than control, respectively.

A novel engineered strain G830 adoptable to high-cell-density fermentation by integrating bacterial hemoglobin vhb (Vitreoscilla hemoglobin gene) into thr operon in the chromosome of PA1 blocking Pta-Ack metabolic pathway through the homologous recombination between the homologous fragments of integrated plasmid and that of chromosome. The engineered strain G830 was characterized by phenotype observation, PCR, thr mutant, acetate acid detection, Western blotting and VHb activity assays. In high dentity fermentation, the cellular respiration, energy metabolism, highest bacterial density and dry bacteria weight of the G830 strain were markedly better than control strains PA1 and BL21. The expression of recombinant prolyl endopeptidase (PEP) in G830 and PA1 under the above condition was high and stable. Their growth situation and fermentation parameters were similar with their parental strains without plasmids, and resided plasmids maintained stably in those strains. It revealed that the integral VHb and acetate metabolism pathway (Pta-Ack) block improved the growth of host strain under low-dissolved-oxygen conditions, enhanced the recombinant proteins production and reduced the accumulation of acetate harmful to bacterial growth. In conclusion, the novel engineering strain G830 was adoptable to high cell density fermentation.

A 3D artificial protein, a salmon calcitonin hexa-polymer, a salmon calcitonin octo-polymer and a human prourokinase, was expressed in the cytoplasma of E.coli GJ980(trxB(-)) mutant. These recombinant proteins containedcysteine residues of different length ranging from 12-22 residues. The mutation was mapped to the gene for thioredoxin reductase(trxB) and was found to eliminate the activity of this enzyme, which was thought to contribute to the sulfhydryl reducing potential of the cytoplasm. Recombinant salmon calcitonin hexapolymer, salmon calcitonin octo-polymer and human prourokinase had more soluble form in cytoplasm of GJ980 mutants than in wild-type strain, while 3D-protein, which has nocysteine residue, still remain in insoluble form. Results indicate the GJ980(trxB(-)) strain allowed the formation of disulphide bonds in the cell cytoplasm which is believed to encourage correct folding and soluble expression of the recombinant proteins.