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ABSTRACT: CXCR4-tropic (X4) variants are associated with faster disease progression than CCR5-tropic variants in HIV infection. We previously reported inhibition of CCR5 expression on U937 cells could protect the cells from HIV-1 infection. Here, we established recombinant adenoviruses containing anti-Sense CXCR4 cDNA, to investigate its role in the protection of HIV entering into target cells. A fragment of 636bp cDNA from CXCR4 mRNA was recombined into adenoviral vector and the recombinant adenovirus was obtained from AD-293 cells. The rates of CXCR4 expression on the MT4 cells infected with recombinant adenovirus were measured by FACS. The MT4 cells infected by recombinant adenovirus were challenged by T-tropic HIV-1 strains and then P24 antigen was assayed. The rate of expression of CXCR4 on MT4 cell infected with recombinant adenovirus was decreased from 42% to 1.12% at 24hours, and to 1.03%, 1.39%, and 1.23% at 48h, 72h and 10days respectively. Compared with Ad-control cells, recombinant adenovirus infected MT4 cells produced much less P24 antigen after being challenged with HIV-1. Furthermore, the recombinant adenovirus had no effects on chemotactic activity and proliferation of the MT4 cells. In conclusion, recombinant adenoviruses containing anti-sense can inhibit CXCR4 expression and resist HIV-1 infection on MT4 cell lines.
Gene 03/2013; · 2.34 Impact Factor
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ABSTRACT: AIMS: Salusin-β is a bioactive peptide with peripheral hypotensive, mitogenic and pro-atherosclerotic effects. The present study was designed to determine the roles of salusin-β in the paraventricular nucleus (PVN) and its relationship with arginine vasopressin (AVP) in hypertension and sympathetic activation. METHODS AND RESULTS: Renovascular hypertension was induced by two-kidney, one-clip (2K1C) in male Sprague-Dawley rats. Acute experiments were carried out 4 weeks after 2K1C or sham-operation under urethane and alpha-chloralose anaesthesia. Renal sympathetic nerve activity (RSNA), mean arterial pressure (MAP), and heart rate (HR) were recorded. Microinjection of salusin-β into the PVN increased the RSNA, MAP, and HR in a dose-related manner, whereas anti-salusin-β IgG in the PVN decreased the RSNA and MAP, and abolished the effects of salusin-β in 2K1C rats. However, either salusin-β or anti-salusin-β IgG in the PVN failed to cause any significant effects in sham-operated rats. The number of salusin-β-like immunopositive neurons in the PVN was significantly increased in 2K1C rats. Salusin-β in the PVN increased the plasma AVP and norepinephrine levels in 2K1C rats, but not in sham-operated rats. Iv injection of dTyr(CH2)5(Me)AVP (an AVP V1-receptor antagonist, AAVP) decreased RSNA and MAP, and abolished the effects of salusin-β in the PVN in 2K1C rats. Microinjection of AAVP into the rostral ventrolateral medulla (RVLM), but not into the PVN, abolished the effects of salusin-β on RSNA and HR. CONCLUSION: Salusin-β in the PVN increases blood pressure, heart rate, and sympathetic outflow via both circulating AVP and AVP in the RVLM in hypertensive rats.
Cardiovascular research 03/2013; · 5.80 Impact Factor
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ABSTRACT: To find out the more efficient induction method through investigating the expansion efficiencies of HIV-infected patients' Vdelta2 T cells induced by zoledronic acid (Zol) or gammadelta TCR monoclonal antibody (mAb).
38 healthy control subjects (HC group) and 65 HIV infected patients (HIV group) were enrolled in this research. Peripheral blood mononuclear cells (PBMCs) of individuals were stimulated by Zol or gammadelta TCR mAb respectively for 14 days at 2.0 x 10(7) cells/ well, and then gammadelta T cells and Vdelta2 subsets frequencies were measured by flow cytometry (FCM) on 0, 7 and 14 day. The absolute numbers of Vdelta2 T cells were calculated and the Vdelta2 T cell expansion efficiencies by these two methods were compared.
The absolute numbers and frequencies of Vdelta2 T cell of HIV groups were lower than those of HC groups significantly on 0 day. After 14 days, the frequencies of Vdelta2 T cell of HIV group and HC group were(17.6 +/- 19.8)% and(64.3 +/- 4.5)% respectively, and the expansion indexes of Vdelta2 T cell were 54 +/- 40 and 74 +/- 29 respectively by induction of gammadelta TCR mAb. However, the frequencies of Vgammadelta2 T cell of HIV group and HC group were (69.6 +/- 21.2)% and (97.3 +/- 1.7)% respectively, and the Vgammadelta2 T cell expansion indexes were 538 +/- 11 and 5984 +/- 721 respectively by induction of Zol.
Zol could induce the vast expansion of Vgammadelta2 T cells of HIV infected patients. The expansion efficiency by Zol was better than that by the gammadelta TCR mAb.
Zhonghua shi yan he lin chuang bing du xue za zhi = Zhonghua shiyan he linchuang bingduxue zazhi = Chinese journal of experimental and clinical virology 12/2012; 26(6):442-5.
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ABSTRACT: We recently found that adipose afferent reflex (AAR) induced by chemical stimulation of white adipose tissue (WAT) increased sympathetic outflow and blood pressure in normal rats. The study was designed to test the hypothesis that AAR contributes to sympathetic activation in obesity hypertension. Male rats were fed with a control diet (12% kcal as fat) or high-fat diet (42% kcal as fat) for 12 weeks to induce obesity hypertension. Stimulation of WAT with capsaicin increased renal sympathetic nerve activity and mean arterial pressure. Both AAR and WAT afferent activity were enhanced in obesity hypertension (OH) compared with obesity nonhypertension (ON) and in ON compared with obesity-resistant or control diet rats. WAT sensory denervation induced by resiniferatoxin caused greater decreases in renal sympathetic nerve activity and mean arterial pressure in OH than ON and in ON than obesity-resistant or control. The depressor effect of resiniferatoxin lasted ≥3 weeks in OH. Leptin antagonist in WAT reduced renal sympathetic nerve activity and mean arterial pressure in OH. WAT injection of capsaicin increased plasma renin, angiotensin II, and norepinephrine levels in OH and caused more c-fos expression in paraventricular nucleus in OH than ON and in ON than obesity-resistant or control rats. Inhibiting paraventricular nucleus neurons with lidocaine attenuated renal sympathetic nerve activity in OH and ON, decreased mean arterial pressure in OH, and abolished the capsaicin-induced AAR in all groups. The results indicate that enhanced AAR contributes to sympathetic activation in OH, and paraventricular nucleus plays an important role in the enhanced AAR and sympathetic activation in OH.
Hypertension 10/2012; 60(5):1280-6. · 6.21 Impact Factor
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ABSTRACT: To investigate the characteristics of γδ T cell subsets in peripheral blood and Vδ1 and Vδ2 T cell subsets proliferation after induction in vitro, and to provide experimental basis for γδ T cells expansion methods in vitro.
Percentages of γδ T cells, Vδ1 and Vδ2 T cells in CD3 T cells from 25 cases of HIV/AIDS patients (HIV group) and 31 cases of healthy adults as control (HC group) were investigated with flow cytometry (FCM); and 10 cases peripheral blood mononuclear cells (PBMCs) from each group were induced and cultured for 14 d by using anti-γδ TCR mAb and IL-2, then the cell amounts were counted, γδ T cells and Vδ1, Vδ2 T cells were detected and analyzed with flow cytometry (FCM) at 0 d, 7 d and 14 d.
The percentages and absolute counts of γδ T cells and V δ2 T cells in HIV group were significantly lower than those in HC group, but those of Vδ1 subsets were significantly higher than those of HC group. After culture for 14 day, the total cell amount of HC group expanded almost 3 times, but those of HIV group expanded a little; The percentages of γδ T cells in HC group were above 80%, but those in HIV group were only about 35%; the percentages of Vδ2 T cells in HC group were about 65%, but those in HIV group were only about 17%.
The proportion of γδ T cells in peripheral blood of HIV/AIDS patients decreased significantly, and Vδ1/Vδ2 ratio was inversed; the expansion effect was not so good to use anti-γδ TCR mAb and IL-2 to induce γδ T cells and Vδ2 subsets of HIV/AIDS, and the Vδ1/Vδ2 ratio inversion could not reverse. More efficient culture methods should be explored.
Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology 03/2012; 28(3):285-7.
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ABSTRACT: Injection of leptin into white adipose tissue (WAT) increases sympathetic outflow. The present study was designed to determine the effects of capsaicin and other chemicals in WAT on the sympathetic outflow and blood pressure and the roles of WAT afferents and hypothalamic paraventricular nucleus (PVN) in the adipose afferent reflex (AAR). The AAR was induced by injection of capsaicin, bradykinin, adenosine, adenosine triphosphate (ATP), or leptin into inguinal WAT (iWAT) or retroperitoneal WAT (rWAT) in anesthetized rats. The iWAT injection of capsaicin increased the renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) but not the heart rate. Bradykinin, adenosine, or leptin but not ATP in the iWAT caused similar effects to capsaicin on the RSNA and MAP. Intravenous, intramuscular, or intradermal injection of capsaicin had no significant effects on the RSNA and MAP. The effects of capsaicin in rWAT were similar to that in iWAT on the RSNA and MAP. Furthermore, injection of capsaicin into the iWAT increased the WAT afferent nerve activities, WAT efferent nerve activity, and brown adipose tissue efferent nerve activity. The iWAT denervation or chemical lesion of the PVN neurons with kainic acid abolished the AAR induced by the iWAT injection of capsaicin. These results indicate that the stimulation of iWAT afferents with capsaicin, bradykinin, adenosine, or leptin reflexly increases the RSNA and blood pressure. The iWAT afferents and the PVN are involved in the AAR induced by capsaicin in the iWAT.
Journal of Applied Physiology 01/2012; 112(6):1008-14. · 3.75 Impact Factor
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ABSTRACT: Intracerebroventricular infusion of NaHS, a hydrogen sulfide (H(2)S) donor, increased mean arterial pressure (MAP). This study was designed to determine the roles of H(2)S in the paraventricular nucleus (PVN) in modulating sympathetic activity and cardiac sympathetic afferent reflex (CSAR) in chronic heart failure (CHF).
CHF was induced by left descending coronary artery ligation in rats. Renal sympathetic nerve activity (RSNA) and MAP were recorded under anesthesia. CSAR was evaluated by the RSNA and MAP responses to epicardial application of capsaicin. PVN microinjection of low doses of a H(2)S donor, GYY4137 (0.01 and 0.1 nmol), had no significant effects on RSNA, MAP and CSAR. High doses of GYY4137 (1, 2 and 4 nmol) increased baseline RSNA, MAP and heart rate (HR), and enhanced CSAR. The effects were greater in CHF rats than sham-operated rats. A cystathionine-β-synthase (CBS) inhibitor, hydroxylamine (HA) in PVN had no significant effect on the RSNA, MAP and CSAR. CBS activity and H(2)S level in the PVN were decreased in CHF rats. No significant difference in CBS level in PVN was found between sham-operated rats and CHF rats. Stimulation of cardiac sympathetic afferents with capsaicin decreased CBS activity and H(2)S level in the PVN in both sham-operated rats and CHF rats.
Exogenous H(2)S in PVN increases RSNA, MAP and HR, and enhances CSAR. The effects are greater in CHF rats than those in sham-operated rats. Endogenous H(2)S in PVN is not responsible for the sympathetic activation and enhanced CSAR in CHF rats.
PLoS ONE 01/2012; 7(11):e50102. · 4.09 Impact Factor
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ABSTRACT: The enhanced cardiac sympathetic afferent reflex (CSAR) is involved in the sympathetic activation that contributes to the pathogenesis and progression of hypertension. Activation of AT(1) receptors by angiotension (Ang) II in the paraventricular nucleus (PVN) augments the enhanced CSAR and sympathetic outflow in hypertension. The present study is designed to determine whether Ang-(1-7) in PVN plays the similar roles as Ang II and the interaction between Ang-(1-7) and Ang II on CSAR in renovascular hypertension.
The two-kidney, one-clip (2K1C) method was used to induce renovascular hypertension. The CSAR was evaluated by the renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) responses to epicardial application of capsaicin in sinoaortic-denervated and cervical-vagotomized rats with urethane and α-chloralose anesthesia. Either Ang II or Ang-(1-7) in PVN caused greater increases in RSNA and MAP, and enhancement in CSAR in 2K1C rats than in sham-operated (Sham) rats. Mas receptor antagonist A-779 and AT(1) receptor antagonist losartan induced opposite effects to Ang-(1-7) or Ang II respectively in 2K1C rats, but losartan had no effects in Sham rats. Losartan but not the A-779 abolished the effects of Ang II, while A-779 but not the losartan blocked the effects of Ang-(1-7). PVN pretreatment with Ang-(1-7) dose-dependently augmented the RSNA, MAP, and CSAR responses to the Ang II in 2K1C rats. Ang II level, AT(1) receptor and Mas receptor protein expression in PVN increased in 2K1C rats compared with Sham rats but Ang-(1-7) level did not.
Ang-(1-7) in PVN is as effective as Ang II in enhancing the CSAR and increasing sympathetic outflow and both endogenous Ang-(1-7) and Ang II in PVN contribute to the enhanced CSAR and sympathetic outflow in renovascular hypertension. Ang-(1-7) in PVN potentiates the effects of Ang II in renovascular hypertension.
PLoS ONE 01/2012; 7(12):e52557. · 4.09 Impact Factor
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ABSTRACT: To investigate reversal effect of histone deacetylase inhibitor LBH589 alone or in combination with proteasome inhibitor bortezomib on drug resistance in acute myeloid leukemia (AML) and its mechanism.
Ex vivo cultures of HL-60/ADM cells and fresh refractory AML cells were treated with LBH589, bortezomib or their combination at varying concentrations. Proliferation capacity, apoptosis rate and reversal of drug resistance were evaluated by MTT assay, dual staining of Hoechst 33342 and Annexin VFITC/PI by flow cytometry, and adriamycin uptake rate with proliferation inhibition, respectively. The change of signal pathway at protein level was analyzed by Western blot.
Synergistic cytotoxicity was observed in the combination treatment with LBH589 and bortezomib against HL-60/ADM cells, as well as the fresh AML cells, the most powerful synergy being observed at 21 nmol/L LBH589 plus 12 nmol/L bortezomib, with CI values of 0.531 and 0.498, respectively by Calcusyn software analysis. Moreover, the accumulation of adriamycin in HL-60/ADM cells was increased more in combination treatment [(64.81 +/- 3.69)%] than in either LBH589 [(28.96 +/- 2.52)%] or bortezomib [(37.29 +/- 3.71)%] alone (P < 0.05), and so did the uptake rate of adriamycin being (64.81 +/- 3.69)%, (28.96 +/- 2.52)% and (37.29 +/- 3.71)% respectively (P < 0.05). The combination treatment induced multiple apoptotic molecules co-action and intracellular drug accumulation contributed to the synergistic cytotoxicity, including caspase activation, PARP cleavage, XIAP downregulation, p53-dependent suppression of Bcl-2 and MRP1 expression via the inhibition of phosphoinositide 3-kinase (PI3K)/Akt/nuclear factor-kappaB (NF-kappaB) signaling pathway.
Combination treatment of drug resistant AML cells with LBH589 and bortezomib produces a synergistic effect of in creating sensitivity to chemotherapy. The mechanism may be mainly resulted from inhibition of PI3K/ Akt/NF-kappaB signaling pathway.
Zhonghua xue ye xue za zhi = Zhonghua xueyexue zazhi 08/2011; 32(8):537-42.
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ABSTRACT: To investigate the characters and changes of peripheral lymphocyte subsets and cytokines in liver transplant receptors with HBV infection in short phases after liver transplantation, and to provide evidences for monitoring post-transplant immune condition of liver transplant receptors.
Peripheral lymphocyte subsets and cytokine levels in pre- and post- transplant 12 h, 3 d, 10 d, 30 d, 60 d of 20 cases of patients with HBV-associated severe hepatic diseases were investigated and analyzed, and were compared respectively with those of 22 cases of healthy adults as control (HC) with flow cytometry (FCM) and ELISA.
The patients' accounts of peripheral lymphocyte subsets before liver transplantation were lower than those of HC significantly, but the accounts decreased significantly after transplantation 12 h. Three days later, the accounts of lymphocyte subsets increased significantly. The percentages of CD3, CD4, CD8 and NK cells got to stable stage from post-transplantation 10 d, and the absolute accounts of post-transplantation 60 d were higher than those of pre-transplantation, but were still lower than those of HC; The IFN-γ and IL-10 levels of post-transplantation 12 h increased several times and decreased after 3 days. The IL-10 levels in post-transplantation 60 d were still higher than those of HC.
The absolute accounts of peripheral lymphocyte subsets increased to stable levels from post-transplantation 10 d, but were still lower than those of HC; Post-transplant immune condition was to Th2 polarization.
Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology 07/2011; 27(7):787-9.
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ABSTRACT: To investigate the characteristics of inhibitory and activating receptor expressions on natural killer (NK) cells in HIV/HCV co-infected patients.
Numbers, frequencies and expressions of activating and inhibitory receptors of NK cells were measured with flow cytometry (FCS) from HIV/HCV co-infected group (n = 24), HCV mono-infected group (n = 34), HIV mono-infected group (n = 21) and healthy control group (HC, n = 20), then analysis and compare were performed among those groups.
The NK cell absolute counts in HIV/HCV group were significantly lower than those in other three groups. The NKP30 and NKP46 frequencies on NK cells in HIV/HCV, HIV and HCV groups were all significantly lower than those in HC group, but there were no significant differences of NKP30 among former three groups; and NKP46 frequencies in HIV/HCV and HIV groups were lower than those in HCV group, but there were no significant differences between former two groups. The NKG2A frequencies in HIV/HCV and HCV groups were all higher than those in HIV and HC groups significantly, but the NKG2A frequencies in HIV group were lower than those in HC group; There were no significant differences of NKG2D, CD158a and CD158b among those four groups.
NK cell numbers and expressions of activiting receptors on NK cells obviously decreased in HIV/HCV co-infected patients, but some inhibitory receptors expressions increased, even higher than those of HIV mono-infected patients. NK cells impairments in HIV/HCV co-infection is more severe than HIV or HCV mono-infection.
Zhonghua shi yan he lin chuang bing du xue za zhi = Zhonghua shiyan he linchuang bingduxue zazhi = Chinese journal of experimental and clinical virology 06/2011; 25(3):182-4.
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Hong-Hui Shen,
Jun Hou, Wei-Wei Chen,
Bing-Ke Bai,
Hai-Bin Wang,
Tong-Sheng Guo,
Ai-Xia Liu,
Yong-Li Li,
Min Zhao,
Pan-Yong Mao,
Jin Li,
Bo-An Li,
Yuan Li-Mao
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ABSTRACT: We analyzed changes in immunologic values over time for 28 hospitalized patients with pandemic (H1N1) 2009. Levels of interleukin-6, interferon-y, and interleukin-10 increased 1 day after illness onset and then decreased to baseline levels. Levels of virus-specific antibody were undetectable 1 day after illness onset and peaked 36 days later.
Emerging Infectious Diseases 06/2011; 17(6):1053-5. · 6.79 Impact Factor
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Jing Zhao,
Jun Xu, Wei-wei Chen,
Yong-li Li,
Yan Tang,
Jia Li,
Hai-bin Wang,
Tong-sheng Guo,
Min Zhao,
Bo-an Li,
Yuan-li Mao
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ABSTRACT: Assessment of detection of IgM antibodies for human enterovirus 71 (EV 71) in early diagnosis for the hand, foot and mouth disease (HFMD).
The sera and throat swabs from 38 patients which were clinical diagnosis as HFMD, were continuous daily collected in our hospital in 2010. These specimens were detected by EV 71 IgM antibodies assay, real time RT-PCR methods for EV 71 and Enterovirus.
Among 38 HFMD patients, the cumulative positive rates of EV 71 IgM antibodies were: 60.5% on day 1, 71.1% on day 2, 81.5% in the first 3-4 days, 92.1% on day 5, 92.1% on day 6, and the positive rate of nucleic acid detected by the real time RT-PCR for EV 71 and Enterovirus were 60.5%, 73.6%.
The positive rate of EV 71 IgM antibodies in the hand, foot and mouth disease just can occur on day 1, and reach to peak on day 5, which can be used as one of indicators of early diagnosis of hand, foot and mouth disease.
Zhonghua shi yan he lin chuang bing du xue za zhi = Zhonghua shiyan he linchuang bingduxue zazhi = Chinese journal of experimental and clinical virology 04/2011; 25(2):140-2.
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ABSTRACT: To establish the real-time fluorescent PCR method for detecting enterovirus, enterovirus 71 and Coxsackievirus A 16 nucleic acid.
Primers and MGB probe were chosen for virus gene. The samples of 38 HFMD patients were analyzed by TaqMan-MGB PCR technique on a fluorescence real-time PCR instrument,and the results were compared with those by conventional RT-PCR.
The real-time fluorescent PCR positive rates of EV, EV71 and Cox A16 were 73.7%, 60.5%, 13.2%; the conventional RT-PCR were 71.1%, 55.3%, 13.2%. There were no significant differences between the two methods.
The real-time fluorescent PCR detecting method of EV, EV71 and Cox A16 nucleic acid have been established successfully.
Zhonghua shi yan he lin chuang bing du xue za zhi = Zhonghua shiyan he linchuang bingduxue zazhi = Chinese journal of experimental and clinical virology 04/2011; 25(2):152-4.
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Wei-wei Chen,
Yang-xin Xie,
Yun-hui Zhang,
Yan-qing Feng,
Bo-an Li,
Bo Li,
Wei Hong,
Jia Liu,
Hong-bin Ma,
Min Zhao,
Yuan-li Mao
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ABSTRACT: To investigate the characters and changes of peripheral white blood cells and lymphocyte subsets of patients with pandemic influenza A virus (H1N1) infection and to provide evidences for diagnosis, treatment and prognosis of influenza A (H1N1) infection.
Peripheral white blood cell parameters and the percentages of lymphocyte subsets in acute and recovery phases of 59 cases of influenza A virus (H1N1) infectious patients (42 mild cases and 17 severe cases) were investigated and analyzed, and compared respectively with those of 43 cases of healthy adults as control (HC) and 24 cases of general influenza A virus (no-H1N1) infectious using whole blood cell analysis and flow cytometry.
Peripheral white blood cell counts of mild cases decreased greatly but those of severe cases did not decrease significantly; the neutrophils of severe cases increased significantly in acute phase; similar to general influenza A virus (no-H1N1) infectious, the peripheral lymphocytes, CD3, CD4, CD8 and B cells of all patients with influenza A virus (H1N1) infection decreased greatly in acute phase and quickly recovered in recovery phase; NK and NKT cells absolute counts of severe cases decreased significantly in acute phase, and the decreasing extent of which were more than 20%.
There were similar characteristics of change in peripheral white blood cells and lymphocyte subsets between patients with pandemic influenza A virus (H1N1) infection and general pandemic A virus (No-H1N1); the great decrease of NK and NKT cells absolute counts may suggest the severe tendency of diseases.
Zhonghua shi yan he lin chuang bing du xue za zhi = Zhonghua shiyan he linchuang bingduxue zazhi = Chinese journal of experimental and clinical virology 10/2010; 24(5):331-3.
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ABSTRACT: Aim: Several β-subunits have been suggested to modulate the electrophysiological properties of the transient outward current (Ito) in cardiac myocytes, including the obligatory β-subunit K+-channel interacting protein (KChIP2) and KCNE2. However, neither KChIP2 nor KCNE2 modulation of Kv4.x (x=2 and/or 3) can fully recapitulate the electrophysiological properties of native Ito. The present study is to investigate how Ito current is modulated when both KChIP2 and KCNE2 are co-expressed. Methods: Kv4.2, KChIP2c, and KCNE2 cDNA were simultaneously transfected into COS-7 cells at a molar ratio of 3:1:1. Whole-cell currents were recorded by the patch-clamp method. Results: In comparison with the current regulated by KChIP2c alone, the co-expression of KCNE2 further slowed Kv4.2 current inactivation kinetics, but diminished KChIP2c-induced positive shift of the voltage-dependent activation of Kv4.2 current. Importantly, co-expression of KCNE2 accelerated the current recovery from inactivation, and caused an “overshoot” of peak current amplitude during Kv4.2 current recovery, a phenomenon which has been uniquely described for human Ito. However, co-expression of KCNE2 exerted no further effect on Kv4.2 current amplitude, the rate of Kv4.2 current activation and voltage-dependent inactivation. Conclusion: Co-expression of Kv4.2 with KChIP2c and KCNE2, but not with KChIP2c or KCNE2 alone, yields a current profile similar to native Ito. Both KChIP2c and KCNE2 simultaneously participate in recapitulation of the electrophysiological properties of Ito in cardiac myocytes.
Acta Pharmacologica Sinica 05/2008; 29(6):653 - 660. · 1.95 Impact Factor
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ABSTRACT: With static-closed-chamber and GC (Agilent 4890), the nitrous oxide (N2O) flux in spring wheat field ecosystem in the Sanjiang Plain of Northeast China was continuously observed in situ from May 2004 to October 2006. The results showed that the N2O flux presented obvious seasonal and inter-annual variation, which was mainly related with precipitation and field water management. The diurnal variation of N2O flux had correlations with the air temperature and the temperature at 5 cm underground. Wheat field ecosystem was the strong sources of atmosphere N2O during plant growth season. The N2O flux decreased obviously in fallowing period, was weaker in freezing period, and increased slowly when soil thawing. The average N2O flux in wheat growth season was 0.190 mg x m(-2) x h(-1), the flux was 0.077 mg x m(-2) x h(-1) from after-reaping to before-freezing period, and 0.017 mg x m(-2) x h(-1) in freezing and thawing period.
Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban 01/2008; 18(12):2777-82.
