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Ping Lin

Publications and source records attributed to Ping Lin.

32 records · Page 2Linked to original sources
PubMed2005

[Studies on the enhancement of DC vaccine to mouse Lewis lung cancer by CpG oligonucleotides].

OBJECTIVE: To investigate whether CpG ODN can affect the antitumor responses of DC-tumor cell vaccine against Lewis lung cancer. METHODS: CpG oligonucleotides 1826 (ODN 1826) were used to promote maturation of DCs in vitro. By fusing DCs with Lewis lung carcinoma L3-8 cells, DC-based tumor cell vaccines were developed. To determine the immune responses to the vaccines, T cell proliferation and cytotoxicity were done in vitro. Therapeutic and prophylactic immunization with DC vaccines were performed in C57BL/6 mice bearing Lewis lung carcinoma. RESULTS: Bone marrow cells cultured in the presence of GM-CSF and IL-4 plus additional ODN 1862 appeared typical morphology of DCs. FACS analyses showed that the mean fluorescence index (MFI) of CD40 expression of DCs stimulated with and without CpG ODN was 24 and 11, respectively, and that of CD86 expression was 75 and 33, respectively. IL-12 secreted by DCs cultured with ODN 1826 was 10-fold as high as that without ODN 1826. Significant T-cell proliferation and T cell-mediated cytotoxicity against L3-8 was induced in vitro. Marked inhibition of tumor growth in L3-8 bearing mice was observed upon prophylactic and therapeutic immunizations with the vaccine. CONCLUSION: CpG ODN can enhance the antitumor responses of DC vaccine by promoting DC maturation.

Animals↗
PubMed2005

[Analysis of essential oil components by GC/FTIR and GC/MS].

The volatile components of clary sage (Salvia sclarea L.) oil were identified by gas chromatography-Fourier transform infrared spectroscopy (GC/FTIR) and gas chromatography-mass spectrometry (GC/MS). The application of GC/FTIR in analysis of essential oil was mainly discussed. The accuracy of qualitative analysis for essential oil was improved by such technique asthe reconstruction of different spectra regions Gram-Schmidt Fourier transforms infrared spectroscopy, and the application of subtracting of Fourier transforms infrared spectroscopy, and the mass spectrometry.

Chromatography, Gas↗
PubMed2004

Pathophysiological significance of a reaction in mouse gastrointestinal tract associated with delayed-type hypersensitivity.

AIM: To explore the pathophysiological significance of delayed type hypersensitivity (DTH) reaction in mouse gastrointestinal tract induced by an allergen 2,4-dinitrochlorobenzene (DNCB). METHODS: BALB/c mice were randomly divided into control and DTH(1-6) groups. After sensitized by DNCB smeared on the abdominal skin, the mice were challenged with DNCB by gavage or enema. The weight, stool viscosity and hematochezia were observed and accumulated as disease active index (DAI) score; the gastrointestinal motility was represented by active charcoal propulsion rate; the colon pathological score was achieved by macropathology and HE staining of section prepared for microscopy; and the leukocyte migration inhibitory factor (LMIF) activity was determined by indirect capillary assay of the absorbance (A) of migrated leukocytes. RESULTS: Active charcoal propulsion rates of small intestine in the DNCB gavages groups were significantly higher than that in the control group (P<0.01). The DAI scores and pathological score in DNCB enema groups were also higher than that in the control group (P<0.05), and there were significant rises in LMIF activity in DNCB enema groups as compared with control groups (P<0.01). CONCLUSION: Mouse gastrointestinal DTH reaction could be induced by DNCB, which might facilitate the mechanism underlying the ulcerative colitis.

Animals↗
PubMed2004

New 1- and 2-dimensional polymeric structures of cyanopyridine complexes of Ag(I) and Cu(I).

Polymeric transition metal chalcogenides have attracted much attention because of their possible unusual properties directly derived from their extended structures. The molecules n-cyanopyridine (n = 2, 3, and 4) and pyridine-3,4-dicarbonitrile are found to function as bidentate or monodentate (only pyridine nitrogen donor atom) ligands in the coordination of silver(I) and copper(I) ions, respectively. The mode of coordination depends on the anion and the crystallization conditions and has been elucidated in all cases by single-crystal X-ray crystallography. We report here the syntheses, structural characterization, and electrical properties of six new polymers, [Ag(2)(2-cyanopyridine)(2)(NO(3))(2)](n)(1), [Ag(4)(3-cyanopyridine)(8)(SiF(6))(2)(H(2)O)(2)](n) (2), [Ag(3-cyanopyridine)(2)(NO(3))](n)(3), [Ag(pyridine-3,4-dicarbonitrile)(2)(NO(3))](n)(4), [Cu(I)(4-cyanopyridine)(2)(SCN)](n)(5), and [Cu(I)(pyridine-3,4-dicarbonitrile)(2)(SCN)](n)(6). Compounds 1 and 2 exhibit novel two-dimensional networks, while 3-6 have one-dimensional chain structures, in which 3 is a single-stranded helix. Room-temperature conductivities of 1, 2, 4, and 6 have been measured and are 3.1 x 10(-)(7), 2.7 x 10(-)(7), 7.4 x 10(-)(6), and 4.3 x 10(-)(5) S.cm(-)(1), respectively. The effect of temperature on the conductivities has been investigated.

Journal Article↗
PubMed2003

Fast analysis of nicotine related alkaloids in tobacco and cigarette smoke by megabore capillary gas chromatography.

A novel fast megabore capillary gas chromatographic (MCGC) method for analysis of 7 nicotine related alkaloids in tobacco and cigarette smoke, including nicotine, nornicotine, myosmine, nicotyrine, anabasine, anatabine and 2,3-dipyridyl, was developed. The use of megabore capillary column GC methodology, equipped with flame ionization detector (FID), provided rapid, unambiguous nicotine related alkaloids analysis. One gram flue-cured tobacco (or Cambridge filter pad), 20 ml ether, and 5 ml 10% sodium hydroxide solution, added with n-heptadecane as the internal standard, were placed in a flask, and the flask was capped and placed in an ultrasonic bath for 15 min. A 1 microl volume was analyzed by capillary GC operating in split-injection mode on a mega bore Simplicity-5 column. This simple procedure was compared with the previously reported packed column GC method and the Griffith still-colorimetric method. The application of the method for analysis of various flue-cured tobaccos and cigarette smoke was discussed.

Alkaloids↗
PubMed2002

Calnuc, an EF-hand Ca(2+)-binding protein, is stored and processed in the Golgi and secreted by the constitutive-like pathway in AtT20 cells.

Calnuc is an ubiquitous, EF-hand Ca(2+) binding protein found in the cytoplasm where it binds to Galphai3, in the Golgi lumen where it constitutes a Ca(2+) storage pool, and secreted outside the cell. Here we investigated the pathway of secretion of calnuc in AtT20 cells. We found by pulse-chase experiments that calnuc is synthesized in the endoplasmic reticulum, transported to the Golgi where it remains greater than 12 h and undergoes posttranslational modification (O-glycosylation and sulfation) followed by secretion into the culture medium. We examined if calnuc is secreted by the constitutive or regulated secretory pathway in AtT20 cells. By immunofluorescence and immunogold labeling, endogenous calnuc is found in immature secretion granules (ISG) but not mature regulated secretory granules (RSG), whereas overexpressed calnuc-green fluorescent protein (GFP) is found in both ISG and RSG, where it colocalizes with ACTH. Neither calnuc nor calnuc-GFP are released by the regulated secretory pathway, suggesting that endogenous calnuc and calnuc-GFP are progressively removed from ISG and RSG during granule maturation. We conclude that calnuc is secreted via the constitutive-like pathway and represents a useful endogenous marker for this pathway in AtT20 cells. Together, these observations indicate that calnuc has a unique itinerary as it is retained in the Golgi and is then constitutively secreted extracellularly where it may influence cell behavior via its Ca(2+)-binding properties.

Adrenocorticotropic Hormone↗
PubMed2002

Subcellular daunorubicin distribution and its relation to multidrug resistance phenotype in drug-resistant cell line SMMC-7721/R.

AIM: To investigate the correlation between subcellular daunorubicin distribution and the multidrug resistance phenotype in drug-resistant cell line SMMC-7721/R. METHODS: The multidrug resistant cell line SMMC-7721/R, a human hepatocellular carcinoma cell line, was established. Antisense oligonucleotides (AS-ODN) were used to obtain different multidrug resistance phenotypes by inhibiting the expression of mdr1 gene and/or multidrug resistance-related protein gene(mrp) using Lipofectamine as delivery agent. Expression of mdr1 and mrp genes was evaluated by RT-PCR and Western blotting. Intracellular daunorubicin (DNR) concentration was measured by flow cytometry. Subcellular DNR distribution was analyzed by confocal laser scanning microscopy. Adriamycin (ADM) and DNR sensitivity was examined by MTT method. RESULTS: Low level expression of mdr1 and mrp mRNAs and no expression of P-Glycoprotein(P-gp) and multidrug resistance-related protein (P(190)) were detected in parental sensitive cells SMMC-7721/S, but over-expression of these two genes was observed in drug-resistant cell SMMC-7721/R. The expression of mdr1 and mrp genes in SMMC-7721/R cells was down-regulated to the level in the SMMC-7721/S cells by AS-ODN. Intracellular DNR concentration in SMMC-7721/S cells was 10 times higher than that in SMMC-7721/R cells. In SMMC7721/S cells intracellular DNR distributed evenly in the nucleus and cytoplasm, while in SMMC-7721/R cells DNR distributed in a punctate pattern in the cytoplasm and was reduced in the nucleus. DNR concentration in SMMC-7721/R cells co-transfected with AS-ODNs targeting to mdr1 and mrp mRNAs recovered to 25 percent of that in SMMC7721/Scells. Intracellular DNR distribution pattern in drug-resistant cells treated by AS-ODN was similar to drug-sensitive cell, and the cells resistance index (RI) to DNR and ADM decreased at most from 88.0 and 116.0 to 4.0 and 2.3, respectively. Co-Transfection of two AS-ODNs showed a stronger synergistic effect than separate transfection. CONCLUSIONS: P-gp and P(190) are two members mediating MDR in cell line SMMC7721/R. Intracellular drug concentration increase and subcellular distribution change are two important factors in multidrug resistance (MDR) formation. The second factor, drugs transport by P-gp and P(190) from cell nucleus to organell in cytoplasm, may play a more important role.

Antibiotics, Antineoplastic↗
PubMed2002

[Change of moisture retention in sandy soil after planting mixed forest of Populus spp. and Robinia pseudoacacia].

The change of soil moisture retention after planting mixed forest of Populus spp. and Robinia pseudoacacia was studied by comparative method. The results showed that soil moisture retention, spatial distribution of soil pore, and soil water capacity were improved and increased in sandy soil after Populus spp. and Robinia pseudoacacia being planted, and the improvement in the mixed forest of Populus spp. and R. pseudoacacia was greater than that in the pure forest of Populus spp. or R. pseudoacacia. The basic reason of soil moisture retention being improved was the increment of soil organic matter, which improved soil pore condition.

Ecosystem↗
PubMed2002

[Autocrine regulation for transforming growth factor-beta 1 by fibroblast in vitro].

OBJECTIVE: To explore the autocrine regulation for the transforming growth factor-beta 1(TGF-beta 1) by the fibroblasts in vitro. METHODS: Fibroblasts were cultured in vitro which isolated from the normal prepuce by circumcision. TGF-beta 1 concentration were determined with ELISA for the different passages and the different time at the same passage. RESULTS: The TGF-beta 1 concentration was different for the distinct passage of fibroblasts and achieved the peak (450 ng/L) at the sixth passage. Among the same fibroblasts, the TGF-beta 1 concentration was different in the various days and passage of the summit (680 ng/L) on the fifth day, which was 2.5 times as high as that of the first day. CONCLUSION: The fibroblasts possess the ability of autocrine of the TGF-beta 1 and have some regularity. It will provide the theory basis for the research about TGF-beta 1 regulation mechanism and the medical application about salvia miltiorrhiza.

Cell Division↗
PubMed1998

Syntheses and Characterizations of a Series of Tetradecanuclear Molybdenum(Tungsten)/Copper/Sulfur Heterobimetallic Cluster Compounds.

Using sulfide ion to substitute the weakly copper(I)-philic ligands of MS(4)(-)(n)()(2)(-)O(n)()/Cu(+) compounds, (M = Mo, W; n = 0, 1), we have prepared and characterized four novel tetradecanuclear clusters having the general formula [(n-Bu)(4)N](4)[M(4)Cu(10)S(16)E(2)E']H(2)O, (M = Mo, E = E' = O for complex 1; M = W, E = (1)/(2)O + (1)/(2)S, E' = O, for complex 2; M = Mo, E = S, E' = (1)/(2)O + (1)/(2)S for complex 3; M = W, E = E' = S, for complex 4). Crystal structures of compounds 1-4 were determined; they are isomorphous and crystallized in the orthorhombic space group Pna2(1), with a = 26.6997(2) Å, b = 19.3133(4) Å, c = 21.4577(4) Å, V = 11064.9(3) Å(3), Z = 4 for [(n-Bu)(4)N](4)[Mo(4)Cu(10)S(18)O].H(2)O (3) and with a = 26.8141(8) Å, b = 19.4412(6) Å, c = 21.4039(5) Å, V = 11157.8(5) Å(3), Z = 4 for [(n-Bu)(4)N](4)[W(4)Cu(10)S(19)].H(2)O (4). The cluster cores have approximate sigma symmetry. The anions 1-4 may be viewed as consisting of one incomplete cubane-like Cu(3)MS(3)E fragment, one trigonal prism-type Cu(3)MS(4), and two butterfly-type Cu(2)MS(3)E' fragments, bridged by two &mgr;(3)-S and one &mgr;(4)-S atoms. There are two (&mgr;(3)-S)Cu(3) configurations in the compounds. Infrared, Raman, and UV/vis spectra of the above compounds are discussed, and the main absorption bands are assigned. (95)Mo NMR spectra and cylic voltammograms are investigated and compared with those of other compounds, (95)Mo NMR spectra show that in the solution there are three kinds of coordination environments of Mo in complexes 1 and 3, and cyclic voltammograms indicate that complexes 1-4 have irreversible electrochemical reductions.

Journal Article↗