Effects of thyroid hormone on myocardial T-type calcium channels at mRNA and protein levels in rats / 中国病理生理杂志

AIM:To observe the effect of thyroxine on the expression of T-type calcium channels Cav3. 1, Cav3. 2 and Cav3. 3 in rat myocardium, and to explore the possible biological mechanism between the changes of the ex-pression of T-type calcium channels and the arrhythmia in hyperthyroid heart disease. METHODS:Healthy SD rats (n=20) were randomly divided into normal control group (n=10) and hyperthyroid heart disease group (n=10). The animal model was established by intraperitoneal injection of levothyroxine for 35 d. The contents of T3 and T4 in serum, the heart-to-body weight ratio, the diameter of cardiac myocytes and electrocardiograph were measured to evaluate hyperthyroid heart disease. Moreover, the mRNA and protein expression levels of T-type calcium channels in the myocardium were measured by RT-PCR, immunohistochemistry and Western blot. RESULTS:After intraperitoneal injection of levothyroxine for 35 d, compared with the normal control group, the serum contents of T3 and T4, the heart-to-body weight ratio and the diameter of cardiac myocytes were significantly increased in hyperthyroid heart disease group (P<0.05), and arrhythmia occurred in hyperthyroid heart disease group. By immunohistochemistry and Western blot, the protein expression of Cav3. 1 in-creased significantly (P<0.05), while the protein expression of Cav3.2 decreased significantly (P<0.01). However, no change of the Cav3. 3 protein was observed. The results of RT-PCR were the same as immunohistochemistry and Western blot. CONCLUSION:Thyroxine promotes the expression of Cav3. 1 in the myocardium but inhibits the expression of Cav3. 2 at mRNA and protein levels, which might be involved in arrhythmia in hyperthyroid heart disease.

Effect of Lang-Chuang-Ding Decoction () on DNA Methylation of CD70 Gene Promoter in Peripheral Blood Mononuclear Cells of Female Patients with Systemic Lupus Erythematosus / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of Lang-chuang-ding Decoction (, LCD) on the expression of DNA methylation of CD70 gene promoter in peripheral blood mononuclear cells (PBMCs) of females with systemic lupus erythematosus (SLE).</p><p><b>METHODS</b>PBMCs isolated from female patients with SLE or healthy donors were cultured and treated with LCD medicated serum or normal serum for 24 or 48 h. The mRNA expressions of CD70 gene in PBMCs were detected by reverse transcription polymerase chain reaction (PCR); the DNA methylation of the CD70 gene promoter region was detected by methylation-specific PCR.</p><p><b>RESULTS</b>After treated with medicated serum for 48 h, the mRNA expression levels of CD70 in PBMCs of SLE patients were signifificantly higher than those of healthy donors (P<0.05); the DNA methylation levels of CD70 promoter region in PBMCs of SLE patients treated with medicated serum for 48 h were signifificantly higher than those treated with fetal bovine serum (P<0.01).</p><p><b>CONCLUSION</b>LCD could inhibit CD70 gene expression in PBMCs of SLE patients by promoting the DNA methylation of CD70 gene promoter.</p>

Effect of montelukast on morphological changes in neurons after ischemic injury / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To determine the effect of montelukast, a cysteinyl leukotriene receptor 1 antagonist, on morphological changes in rat neurons after ischemic injury.</p><p><b>METHODS</b>The in vivo ischemia injury was induced by oxygen-glucose deprivation (OGD) for 2 h and reperfusion (R) for 24 h (OGD/R) in rat neurons primary culture and mixed cortex culture. In the presence or absence of various concentrations of montelukast, neuron number, area of neuron, number of neuritis per neuron, branch number of primary neuritis and primary neurite length were determined for evaluating morphological changes in neurons.</p><p><b>RESULTS</b>OGD/R significantly reduced neuron number, and altered neuron morphology. In cortical neuron cultures, montelukast (0.0001-1 μmol/L) attenuated OGD/R-induced reduction in neuron number, and inhibited OGD/R-induced increase in branch number of primary neuritis. In the mixed cultures, montelukast (0.0001-0.1 μmol/L) increased the primary neurite length, and reduced number of neuritis and branch number of primary neurite after OGD/R.</p><p><b>CONCLUSION</b>Montelukast has a protective effect on ischemic injury in neurons.</p>

Construction of HEK293 cell lines expressing hCysLT₂ receptor and its application in screening of antagonists / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To construct HEK293 cell lines stably expressing hCysLT(2) receptor, and to evaluate its application in screening of synthetic compounds with antagonist activity.</p><p><b>METHODS</b>The recombinant plasmid pcDNA3.1(+)-hCysLT(2) was transfected into HEK293 cells using Lipofectamin 2000. The transfected HEK293 cells were selected in 96 well plates by limiting dilution with 600 μg/ml C418 for 8 weeks. The expression of human CysLT(2) receptor was detected by RT-PCR and immunofluorescence staining. In HEK293 cells stably transfected with hCysLT(2), the agonist LTD(4)-induced elevation of intracellular calcium concentration ([Ca2(+)]i) was measured as the index for screening compounds with antagonist activity.</p><p><b>RESULT</b>After selection in 96 well plates by limiting dilution, 12 monoclones were obtained and 11 of them highly expressed hCysLT(2) receptor. The positive control ATP at 50 μmol/L and LTD(4) at 100 nmol/L elevated [Ca2(+)]i in hCysLT(2)-HEK293 cells. AP-2100984 inhibited LTD(4)-induced [Ca2(+)]i elevation, but selective CysLT(1) receptor antagonists did not exert such an effect. The newly synthesized compounds DXW2, DXW3, DXW4, DXW5, DXW9, DXW25, DXW26, DXW29 and DXW35 at 1 μmol/L significantly inhibited LTD(4)-induced [Ca2(+)]i elevation. The IC(50) values of DXW4 and DXW5 were 0.25 μmol/L and 7.5 μmol/L.</p><p><b>CONCLUSION</b>HEK293 cell lines stably expressing hCysLT(2) receptor have been successfully constructed, and can be used to screen compounds with CysLT(2) receptor antagonist activity.</p>

Effects of agonist and antagonist of cysteinyl leukotriene receptors on differentiation of rat glioma C6 cells / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the role of cysteinyl leukotriene (CysLT) receptors in the differentiation of rat glioma C6 cells.</p><p><b>METHODS</b>Rat glioma C6 cells were treated with the agonist LTD(4), the CysLT(1) receptor antagonist montelukast and the differentiation inducer forskolin. Cell morphology and GFAP protein expression were determined after treatments.</p><p><b>RESULT</b>Forskolin (10 μmol/L) induced morphological changes and GFAP protein expression (cell differentiation) in C6 cells, but LTD(4) (0.1-100 nmol/L) did not induce these changes. Montelukast (1 μmol/L) alone did not affect C6 cell differentiation, while it induced the differentiation when combined with the LTD(4) (100 nmol/L).</p><p><b>CONCLUSION</b>The CysLT(2) receptor may modulate the differentiation of rat glioma C6 cells.</p>

Deficiency of water channel AQP4 aggravates NMDA-induced brain injury in mice / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To evaluate the role of water channel AQP4 in NMDA-induced brain injury in mice.</p><p><b>METHODS</b>In AQP4 gene knockout (AQP4(-/-)) mice, brain injury was induced by microinjection of NMDA into the cortex. The injured area was determined by toluidine blue staining, degenerated neurons were detected by Fluro-Jade B staining, and increased blood-brain barrier (BBB) permeability was evaluated by IgG immunostaining.</p><p><b>RESULT</b>Compared with wild-type mice, AQP4(-/-) mice exhibited increased cortical lesion area, aggravated neuron degeneration, and increased BBB disruption after NMDA microinjection.</p><p><b>CONCLUSION</b>AQP4 may play a protective role in NMDA-induced brain injury in mice.</p>

Method for screening cysteinyl leukotriene receptor 2 antagonists and preliminary screening of compounds / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To establish a method for screening cysteinyl leukotriene receptor 2 (CysLT(2)) antagonists and to preliminarily screen a series of synthetic compounds.</p><p><b>METHODS</b>Rat glioma cell line (C6 cells) highly expressing CysLT(2) receptor was used. Intracellular calcium concentration was measured after stimulation with the agonist LTD(4),which was used to screen compounds with antagonist activity for CysLT(2) receptor. Bay u9773, a CysLT1/CysLT(2) receptor non-selective antagonist, and AP-100984, a CysLT(2) receptor antagonist, were used as control.</p><p><b>RESULT</b>PT-PCR showed a higher expression of CysLT(2) receptor in C6 cells. LTD(4) at 1 mumol/L significantly increased intracellular calcium in C6 cells; the maximal effect was about 37.5% of ATP, a positive stimulus.LTD(4)-induced increase of intracellular calcium was blocked by CysLT(2) receptor antagonists, but not by CysLT(1) receptor antagonists. Among the synthetic compounds, D(XW-)1,2,13,23,29 and 30 inhibited LTD(4)-induced increase of intracellular calcium.</p><p><b>CONCLUSION</b>LTD(4)-induced change in intracellular calcium in C6 cells can be used as a screening method for CysLT(2) receptor antagonists. The compounds, D(XW-)1,2,13,23,29 and 30, possess antagonist activity for CysLT(2) receptor.</p>

5-Lipoxygenase/cysteinyl leukotriene pathway is not involved in injury of rat C6 glioma cells induced by oxygen-glucose deprivation / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To determine whether oxygen-glucose deprivation (OGD) induces C6 cell injury, and whether 5-lipoxygenase (5-LOX)/cysteinyl leukotriene (CysLT) pathway is involved in OGD-induced injury.</p><p><b>METHODS</b>After OGD treatment and recovery for various durations, the viability of C6 cells was determined, and the effects of 5-LOX inhibitors and CysLT receptor antagonists were investigated. Intracellular distribution of 5-LOX protein was detected by immunocytochemistry, and the mRNA expressions of CysLT1 and CysLT2 receptors were detected by RT-PCR. The effect of leukotriene D(4) (LTD(4)) on C6 cells was also investigated.</p><p><b>RESULT</b>OGD for 4-8 h followed by recovery for 24-72 h significantly induced C6 cell injury. Neither 5-LOX inhibitors nor CysLT receptor antagonists inhibited OGD-induced injury. OGD did not induce 5-LOX translocation into the nuclear membrane. C6 cells highly expressed CysLT(2) receptor, but the expression of CysLT1receptor was much weaker; the expression was not affected by OGD. In addition, LTD(4) did not affect C6 cells significantly.</p><p><b>CONCLUSION</b>OGD can induce C6 cell injury, but 5-LOX/CysLT pathway might be not involved in OGD-induced injury.</p>

Control Hands Pollution to Prevent Nosocomial Infection / 中华医院感染学杂志

OBJECTIVE To explore the correlation between hands pollution and nosocomial infection,and to raise measures to keep hand hygiene.METHODS To evaluate the condition of hand pollution and hand washing,the relationship between hands pollution and nosocomial infection,and measures to improve hand hygiene.RESULTS Most nosocomial infections were transmitted by the hands pollution,bacteria of which were thought to be the main microbial population of nosocomial infection.Handwashing was considered to be the most important intervention to prevent nosocomial infections.However,the present studies indicated that there was not enough handwashing practice among the medical personnel,lacking the consciousness of the importance of hand cleaning,misunderstanding the standard hand cleaning steps,like the length of washing time and the choose of hand disinfectant,and inadequately providing the hospital condition for cleaning work,all these played an important role in declining the efficiency of hand disinfection in hospital.Medical workers could achieve their goal through the improving of the above aspects of work.CONCLUSIONS Hands pollution is closely related to nosocomial infection.Handwashing can reduce nosocomial infections.

Preventive Effect on Nosocomial Infection with Herbal Medicine Atractylodes chinensis Disinfectant for Air Sterilization in Cardiothoracic Surgery / 中华医院感染学杂志

OBJECTIVE To observe the preventive effect on nosocomial infection by the herbal medicine Atractylodes chinensis disinfectant for air sterilization in cardiothoracic surgery.METHODS A.chinensis disinfectant and ultraviolet irradiation were used to disinfect the patients′ rooms of our cardiothoracic surgery department.The total number of germ and fungus in the indoor air before and after using the two methods were collected.The nosocomial infection rates of the same period were also studied.RESULTS A.chinensis disinfectant had strong effect on sterilization of indoor germs and fungi,and the sterilization rate was 92.7%.The comparison between A.chinensis disinfectant and ultraviolet irradiation showed significant difference in their disinfection effects,while no significant difference in their nosocomial infection rates.CONCLUSIONS The herbal medicine A.chinensis disinfectant can achieve good sterilization effect and prevent nosocomial infection.