Inflammation is closely related to stroke prognosis, and high inflammation status leads to poor functional outcome in stroke. DNA methylation is involved in the pathogenesis and prognosis of stroke. However, the effec...Inflammation is closely related to stroke prognosis, and high inflammation status leads to poor functional outcome in stroke. DNA methylation is involved in the pathogenesis and prognosis of stroke. However, the effect of DNA methylation on stroke at high levels of inflammation is unclear. In this study, we constructed a hyperinflammatory cerebral ischemia mouse model and investigated the effect of hypomethylation and hypermethylation on the functional outcome. We constructed a mouse model of transient middle cerebral artery occlusion and treated the mice with lipopolysaccharide to induce a hyperinflammatory state. To investigate the effect of DNA methylation on stroke, we used small molecule inhibitors to restrain the function of key DNA methylation and demethylation enzymes. 2,3,5-Triphenyltetrazolium chloride staining, neurological function scores, neurobehavioral tests, enzyme-linked immunosorbent assay, quantitative reverse transcription PCR and western blot assay were used to evaluate the effects after stroke in mice. We assessed changes in the global methylation status by measuring DNA 5-mc and DNA 5-hmc levels in peripheral blood after the use of the inhibitor. In the group treated with the DNA methylation inhibitor, brain tissue 2,3,5-triphenyltetrazolium chloride staining showed an increase in infarct volume, which was accompanied by a decrease in neurological scores and worsening of neurobehavioral performance. The levels of inflammatory factors interleukin 6 and interleukin-1 beta in ischemic brain tissue and plasma were elevated, indicating increased inflammation. Related inflammatory pathway exploration showed significant overactivation of nuclear factor kappa B. These results suggested that inhibiting DNA methylation led to poor functional outcome in mice with high inflammation following stroke. Further, the effects were reversed by inhibition of DNA demethylation. Our findings suggest that DNA methylation regulates the inflammatory response in stroke and has an important role in the functional outcome of hyperinflammatory stroke.展开更多
A novel yet simple, rapid and robust thermometric endpoint titration (TET) method for the determination of sodium in various foodstuffs is described. Sodium reacts exothermically with aluminium in the presence of an e...A novel yet simple, rapid and robust thermometric endpoint titration (TET) method for the determination of sodium in various foodstuffs is described. Sodium reacts exothermically with aluminium in the presence of an excess of potassium and fluoride ions to form NaK2AlF6 (“elpasolite”). This reaction forms the basis of a ro- bust, reliable analytical procedure suitable for routine process control. The reaction of calcium under similar conditions (to form KCaAlF6) suggests that potentially, calcium may interfere in the determination of sodium in some foodstuffs. Results of an investigation suggest that at molar ratios [Ca]/[Na] < 0.85, an error of <1% of the measured value of sodium is incurred.展开更多
Objective To investigate the expression of TET2 mRNA and protein in the bone marrow mononuclear cells （BMMNC） of patients with myelodysplastic syndrome （MDS） and its clinical significance. Methods The expression o...Objective To investigate the expression of TET2 mRNA and protein in the bone marrow mononuclear cells （BMMNC） of patients with myelodysplastic syndrome （MDS） and its clinical significance. Methods The expression of TET2 mRNA and protein in bone marrow mononuclear cells （BMMNC） of 32 patients with MDS and 20 healthy donors was examined by qPCR and Western blot. Results The expression of TET2 mRNA in BMMNC was down-regulated in MDS patients compared with the donor group [（0.41±0.28）% vs. （1.07±0.56）%] （P〈0.001）. Compared with lower expression group （TET2〈0.4） [（6.53±6.17）%], patients with higher expression of TET2 ≥0.4） presented significantly lower proportion of bone marrow blasts [（1.21±1.56）%1 （P〈0.05）. The expression of TET2 mRNA in BMMNC of MDS patients was inversely correlated with malignant clone burden （t=--0.398, P〈0.05） and IPSS r=-0.412, P〈0.05）. The expression of TET2 protein was down-regulated in MDS patients compared with that in the donor group. Conclusions The mRNA and protein expression of TET2 in BMMNC of MDS patients is decreased, which might be useful as an important parameter for the evaluation of MDS clone burden.展开更多
基金supported by the National Natural Science Foundation of China,No.82171270 (to ZL)Public Service Platform for Artificial In telligence Screening and Auxiliary Diagnosis for the Medical and Health Industry,Ministry of Industry and Information Technology of the People's Republic of China,No.2020-0103-3-1 (to ZL)+3 种基金the Natural Science Foundation of Beijing,No.Z200016 (to ZL)Beijing Talents Project,No.2018000021223ZK03 (to ZL)Beijing Municipal Committee of Science and Technology,No.Z201 100005620010 (to ZL)CAMS Innovation Fund for Medical Sciences,No.2019-I2M-5-029 (to YongW)。
文摘Inflammation is closely related to stroke prognosis, and high inflammation status leads to poor functional outcome in stroke. DNA methylation is involved in the pathogenesis and prognosis of stroke. However, the effect of DNA methylation on stroke at high levels of inflammation is unclear. In this study, we constructed a hyperinflammatory cerebral ischemia mouse model and investigated the effect of hypomethylation and hypermethylation on the functional outcome. We constructed a mouse model of transient middle cerebral artery occlusion and treated the mice with lipopolysaccharide to induce a hyperinflammatory state. To investigate the effect of DNA methylation on stroke, we used small molecule inhibitors to restrain the function of key DNA methylation and demethylation enzymes. 2,3,5-Triphenyltetrazolium chloride staining, neurological function scores, neurobehavioral tests, enzyme-linked immunosorbent assay, quantitative reverse transcription PCR and western blot assay were used to evaluate the effects after stroke in mice. We assessed changes in the global methylation status by measuring DNA 5-mc and DNA 5-hmc levels in peripheral blood after the use of the inhibitor. In the group treated with the DNA methylation inhibitor, brain tissue 2,3,5-triphenyltetrazolium chloride staining showed an increase in infarct volume, which was accompanied by a decrease in neurological scores and worsening of neurobehavioral performance. The levels of inflammatory factors interleukin 6 and interleukin-1 beta in ischemic brain tissue and plasma were elevated, indicating increased inflammation. Related inflammatory pathway exploration showed significant overactivation of nuclear factor kappa B. These results suggested that inhibiting DNA methylation led to poor functional outcome in mice with high inflammation following stroke. Further, the effects were reversed by inhibition of DNA demethylation. Our findings suggest that DNA methylation regulates the inflammatory response in stroke and has an important role in the functional outcome of hyperinflammatory stroke.
文摘A novel yet simple, rapid and robust thermometric endpoint titration (TET) method for the determination of sodium in various foodstuffs is described. Sodium reacts exothermically with aluminium in the presence of an excess of potassium and fluoride ions to form NaK2AlF6 (“elpasolite”). This reaction forms the basis of a ro- bust, reliable analytical procedure suitable for routine process control. The reaction of calcium under similar conditions (to form KCaAlF6) suggests that potentially, calcium may interfere in the determination of sodium in some foodstuffs. Results of an investigation suggest that at molar ratios [Ca]/[Na] < 0.85, an error of <1% of the measured value of sodium is incurred.
基金supported by grants from the National Natural Science Foundation of China(No.30971286, 30971285,81170472)Chinese Medical Association of Molecular Biology Clinical Application Research Special Funds(No.CAMB042010)+1 种基金The"Eleventh Five-year Plan"National Science and Technology Support Plan(No. 2008BA161B00)Health Industry Research Special Project (No.201002024)
文摘Objective To investigate the expression of TET2 mRNA and protein in the bone marrow mononuclear cells （BMMNC） of patients with myelodysplastic syndrome （MDS） and its clinical significance. Methods The expression of TET2 mRNA and protein in bone marrow mononuclear cells （BMMNC） of 32 patients with MDS and 20 healthy donors was examined by qPCR and Western blot. Results The expression of TET2 mRNA in BMMNC was down-regulated in MDS patients compared with the donor group [（0.41±0.28）% vs. （1.07±0.56）%] （P〈0.001）. Compared with lower expression group （TET2〈0.4） [（6.53±6.17）%], patients with higher expression of TET2 ≥0.4） presented significantly lower proportion of bone marrow blasts [（1.21±1.56）%1 （P〈0.05）. The expression of TET2 mRNA in BMMNC of MDS patients was inversely correlated with malignant clone burden （t=--0.398, P〈0.05） and IPSS r=-0.412, P〈0.05）. The expression of TET2 protein was down-regulated in MDS patients compared with that in the donor group. Conclusions The mRNA and protein expression of TET2 in BMMNC of MDS patients is decreased, which might be useful as an important parameter for the evaluation of MDS clone burden.
