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ABSTRACT: T cell DNA methylation levels decline with age, activating genes such as KIR and TNFSF7 (CD70), implicated in lupus-like autoimmunity and acute coronary syndromes. The mechanisms causing age-dependent DNA demethylation are unclear. Maintenance of DNA methylation depends on DNA methyltransferase 1 (Dnmt1) and intracellular S-adenosylmethionine (SAM) levels, and is inhibited by S-adenosylhomocysteine (SAH). SAM levels depend on dietary micronutrients including folate and methionine. SAH levels depend on serum homocysteine concentrations. T cell Dnmt1 levels also decline with age. We hypothesized that age-dependent Dnmt1 decreases synergize with low folate, low methionine or high homocysteine levels to demethylate and activate methylation-sensitive genes. T cells from healthy adults ages 22-81, stimulated and cultured with low folate, low methionine, or high homocysteine concentrations showed demethylation and overexpression of KIR and CD70 beginning at age approximately 50 and increased further with age. The effects were reproduced by Dnmt1 knockdowns in T cells from young subjects. These results indicate that maintenance of T cell DNA methylation patterns is more sensitive to low folate and methionine levels in older than younger individuals, due to low Dnmt1 levels, and that homocysteine further increases aberrant gene expression. Thus, attention to proper nutrition may be particularly important in the elderly.
Experimental gerontology 04/2010; 45(4):312-22. · 3.34 Impact Factor
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ABSTRACT: Recent studies have shown that NS-398, a highly selective COX-2 inhibitor, can enhance the inhibition effects of cisplatin on adenocarcinoma cell proliferation, but the mechanism is still unknown. The aim of this study is to explore the mechanism about the synergistic effects of NS-398 and cisplatin to human lung adenocarcinoma cell line.
Differentially expressed proteins were separated in human lung adenocarcinoma cells treated with NS-398 and/or cisplatin by immobilized pH gradient-based two-dimensional gel electrophoresis (2-DE), then 19 out of obtained proteins were identified by peptide mass fingerprint (PMF) based on matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) and database searching.
There were 22 down-regulated proteins and 2 up-regulated proteins in NS-398+cisplatin combination group compared with control groups. Finally six proteins were identified, in which some were cytokeratins, some were associated with proliferation and apoptosis, and the others were involved in metabolism of tumor cells.
The down-regulation of HSP90 and triosephosphate isomerase may be related to the synergistic effects of NS-398 and cisplatin on human lung adenocarcinoma cells.
Zhongguo fei ai za zhi = Chinese journal of lung cancer 08/2007; 10(4):263-8.
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ABSTRACT: To establish a rapid polymerase chain reaction (PCR)method for detection of staphylococcus aureus in milk, ice cream and meat.
Two pairs of oligonucleotide primers were designed with thermo nuclease gene nuc and surfaced-associated fibrinogen-binding protein gene ClfA to detect staphylococcus aureus. Fifty-two staphylococcus aureus and thirty-one non staphylococcus aureus were amplified by PCR to verify the specificity. Various numbers of bacteria were added into milk, ice cream and meat. After enrichment, DNA extracted in different time was amplified by PCR to verify detection limit.
Each primer pair allows specific detection. The limit of detection was 10 cfu/g (ml) in three kinds of food. Whole procedure of detection could be finished in 24 hours.
A rapid, sensitive and specific PCR method can be applied detecting staphylococcus aureus in milk, ice cream and meat.
Wei sheng yan jiu = Journal of hygiene research 04/2007; 36(2):183-6.
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ABSTRACT: In recent years, many investigations have showed that COX-2 inhibitors not only inhibit the growth of tumor cells but also enhance the cytotoxicity of anticancer drugs, such as NS-398, a selective COX-2 inhibitor. But the effect of NS-398 combined with chemotherapy agent cisplatin on growth of lung adenocarcinoma cells and its mechanism are still unknown. The aim of this study is to investigate the effect of NS-398 combined with cisplatin on proliferation of human lung adenocarcinoma cell lines, and to explore their mechanisms.
Synergistic effect of NS-398 and cisplatin on proliferation of human lung adenocarcinoma cell lines was detected by MTT growth assay, and data were analyzed by SPSS general linear models procedure to determine the IC₅₀ of each drug alone. Combined index (CI) was analyzed to determine the combined effect of drugs. Apoptosis and cell cycle distribution were detected by fluorescence staining of Acridine orange (AO) and Ethidium bromide (EB) and flow cytometry.
The various concentration of NS-398 in combination with cisplatin resulted in the reduction of IC₅₀ of cisplatin by 48.25%-62.44% in A549 cells, and by 43.34%-69.61% in SPC-A-1 cells. The CI of NS-398 and cisplatin in the two cell lines ranged from 0.4 to 0.9, which indicated that they acted in slight synergistic to synergistic pattern. The apoptotic rate at 24h and 48h in the combined groups was significantly higher than those of the control groups, and the S-phase cell fractions at 48h and 72h were obviously higher than those of the control groups. There was a positive correlation between apoptotic rate and S-phase cell fraction in the combined groups (r=0.882,P= 0.01).
NS-398 can improve growth inhibition of cisplatin on lung adenocarcinoma cells, and the two agents act in synergistic way. This synergistic effect may be related to apoptosis pathway.
Zhongguo fei ai za zhi = Chinese journal of lung cancer 02/2005; 8(1):8-13.
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Yepeng Li,
Chunhui Han,
Yanjun Li,
Yuwei Li,
Xi Zhao,
Kai Zhong,
Tingjun Chen,
Ming Zhang,
Fucheng Fan,
Yong Tao,
Rong Ji
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ABSTRACT: To study impact of extra waters on immunosystem in mice-alkaline ionized water, mineral-ecology water, activated water, and pure water.
According to Function Assessment and Experiment for Function Food, 1996, the ratio of spain and body weight, the ratio of thymus and body weight, the delayed type hypersensitivity (DTH), the phagocytosing functions by cock RBC, the plaque forming cell (PFC) and HC50 testing were assessment with 120 male Balb/c mice of 17.8 - 23.3 g (group I), the mice were divided into four group, and drank daily the four kinds of waters respectively until 50 days. The lymph cell transformation by ConA and NK cell activity were assessment with other l20 male Balb/c mice of 17.8 - 23.3 g (group II), the mice were divided into four group and drank daily the four kinds of waters respectively until 50 days. The phagocytosing functions by carbon powder were assessment with other 120 female Balb/c mice of 16.7 - 22.0 g (group III) were divided into four group and drank daily the four kinds of waters respectively until 50 days. The data were statisticed by Stata soft.
Other three waters compared with the pure water: (1) Alkaline ionized water and activated water can alleviate the body weight increase of male Balb/c mouse (P < 0.01 & P < 0.05), but alkaline ionized water, mineral-ecology water, activated water don't impact on the female Balb/c mouse body weight (P > 0.05). (2) Activated water can remarkably increase the ratio of thymus and body weight (P < 0.05), and increase the phagocytosing ability by cock RBC (P < 0.01), and increase the NK cell activity (P < 0.01). (3) The three extra waters don't impact on other items for the Balh/c mouce.
The study must be continued to impact on immunosystem in mice for extra waters.
Wei sheng yan jiu = Journal of hygiene research 08/2004; 33(4):422-5.
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ABSTRACT: A new and an efficient method for analyzing kojic acid in aspergillus oryzae ferment by ion-pair reversed-phase high performance liquid chromatography was developed. The kojic acid was well separated on a C18 column using methanol-0.01 mol/L disodium hydrogen phosphate and 2 mmol tetrabutylammonium bromide (4:96) as the mobile phase, followed by an UV detection at 226 nm. The detection limit was 0.012 microgram/ml. The spiked recoveries in wort-yeast culture, wort-peptone culture and potato-yeast-sugar culture were 98.2%, 103.4% and 97.2%, respectively. The RSD values were 0.51%, 0.45% and 0.43% respectively.
Wei sheng yan jiu = Journal of hygiene research 08/2003; 32(4):384-5.
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ABSTRACT: In order to evaluate the anti-radiation effect of TPP (tea polyphenols), 60 female Kunming mice were chosen as group I for WBC (white blood cell) count, and another 60 female Kunming mice were set as group II for survival test. TPP was administrated orally to the mice. The results revealed that no significant difference was observed in the number of white blood cells in every test after the irradiation compared with that of the control group. Consequently, TPP showed no observably effect on the protection of the number of WBC against high dose irradiation. However, Mice survival rate of 0.83 ml/kg BW group and 25.0 ml/kg BW group are remarkably higher than that of the control group(P < 0.01). On the contrary, the control group had no survivor 30 days after the irradiation. This suggested that TPP can increase the survival rate evidently on mice after irradiation.
Wei sheng yan jiu = Journal of hygiene research 10/2002; 31(5):394-5.
